bluuebunny/crossref_metadata_2025 huggingface dataset:
The Spread of Bacterial Infection; Group-to-Group Infection
Authors: Topley W. W. C. , Wilson G. S.
Published: May 2009

Susceptible mice have been placed in contact with infective individuals of the same species, separated from them after a definite period, and placed in contact with a further group of normal mice. This process has then been repeated again and again, the number of groups exposed varying, in different experiments, from three to twelve. In this way the spread of infection has been limited to that occurring between any one group and the group immediately following it.

Under these circumstances infection has spread far less readily than was the cases in other experiments, in which the mice were retained as a single population, and in which infection could spread in any direction among all the individuals at risk.
An Experimental Study of the Neisser-Wechsberg Phenomenon
Authors: Pandit C. G.
Published: May 2009

(1) The inhibiting phenomenon of Neisser and Wechsberg, as frequently observed with bacteriolytic sera, can also be shown to occur with haemolytic sera.

(2) This phenomenon develops early during immunisation, when it is very marked; but as immunisation proceeds it tends to disappear.

(3) In sera examined some time after their removal the inhibiting faculty is seen to disappear first, before any marked change is noticed in its bactericidal titre. This can be shown to occur in vivo also.

(4) The inhibiting faculty is observed only with inactivated sera; fresh and active sera showing complete bactericidal activity at all times. The effects are not however due to complementoids produced by inactivation.

(5) The phenomenon is not due to the action of any of the known anti bodies, or special “inhibiting antibodies”; but it is due probably to dis sociation of the antigen-amboceptor complex. Such dissociation only occurs when amboceptors are present in excess. This explains why inhibition occurs only with high doses of an immune serum.

The serum to be used should be without an antiseptic. Commercially prepared antisera usually contain a small amount of it. It is shown that corpuscles sensitised in them undergo haemolysis without the addition of complement (see p. 427).

(6) Since it is known that the union of antigen and amboceptor is not always a firm one, it is suggested that during early days of immunisation amboceptors of a weak combining affinity are produced. These are replaced later by those which are capable of a more permanent union with them (antigens).

(7) The name “complement-blocking” is not an appropriate one, as com plement could be shown to exist free in the inhibiting fluids. It should rather be spoken of as an “amboceptor-dissociation” effect.

(8) Inhibition is specific. An attempt was made to utilise this fact in differ entiation of strains of true cholera but it was found to have no definite diagnostic value.

The writer wishes to express his indebtedness to Prof. Hewlett for sug gesting the problem to him and also for his kind guidance and encouragement during the course of the experiments. His thanks are also due to Dr Taylor for his valuable assistance.
On the Fungi causing Ringworm in Children attending London Country Council Schools
Authors: Hare J. G. , Tate P.
Published: May 2009

1. Cultures were obtained from 69 cases of ringworm of children in London County Council Schools.

2. Three of them were cases of favus, the parasite in each case being Achoroion Schōnleinii.

3. Microsporums are responsible for most of the ringworm, and were isolated from 54 of the 69 cases, or 78 per cent. Microsporum audouini was found in 70 per cent, of the Microsporum infections; M. lanosum and M. felineum each in one case; and 4 other cultures were obtained, comprising 3 species which have not yet been identified.

4.Endothrix Trichophytons were found in 17 per cent, of the cases and include the species Trichophyton crateriforme, T. sulfureum, T. acuminatum and T. violaceum.

5.A list of the species isolated arranged, according to the new classification of Ota and Langeron, is given.

6.The results are compared with those previously obtained in London by Fox and Blaxall, and Adamson, with which they broadly agree.
A Preliminary Study of the Chemical Nature of the Toxic Substances produced by the Salmonella Group of Organisms
Authors: Ecker E. E. , Rimington C.
Published: May 2009

The production of soluble toxic substances in broth cultures of these bacteria is well known. Berkefeld nitrates of such cultures are usually toxic for the rabbit upon intravenous injection. A review of the literature has been given by Ecker (1917, 1925) and by Branham (1925). Subsequent studies of these workers have shown that Berkefeld filtrates of synthetic medium (Braun and Cahn-Bonner, 1921) cultures yielded toxic substances inducing a similar reaction in the rabbit. Little is known concerning the nature of these substances beyond that they are relatively thermostabile; on dialysis of the broth culture nitrate the toxin is withheld within the collodium sac.
The Weil-Felix Reaction in Typhus Fever
Authors: Cruickshank Robert
Published: May 2009

(1)Statistical evidence cannot be deduced from such a small series of cases, but it would seem that the extent to which agglutinins for B. proteus X. 19 (Weil-Felix) were formed in the blood varied directly as the severity of the illness, since with the older and more ill patients a much higher dilution of serum agglutinated the organism at or near crisis than was the case with the younger patients, who were less acutely ill. An exception to this rule was met with in one case (Mrs E. R.), whose serum did not agglutinate the organism in a dilution beyond 1: 250, although she was the most severely ill of all the patients. It is possible that failure of agglutinin-formation resembles the absence of leucocytosis in the severely ill case of pneumonia and may be regarded as a bad prognostic feature.

(2)A positive Weil-Felix reaction was not obtained before the fifth day of illness, nor in any case before the characteristic rash appeared, so that the reaction is of little value as a factor in the early diagnosis of typhus. Later, a reaction in which a dilution of the serum of 1: 50 agglutinates the organism may be regarded as diagnostic of typhus.

(3)The Weil-Felix reaction remained positive for the longest period in those cases whose serum agglutinated in highest dilution, and in these patients a positive reaction (1: 25–1: 50) was still present nine to twelve weeks after infection, whereas in the milder cases, and in Mrs E. R., the reaction became negative in six to eight weeks from the onset of illness.

(4)In view of this heterologous reaction in typhus, it is interesting to record that the Wassermann reaction obtained before crisis was positive in four out of six cases. It was still positive in two of the most severely ill patients a week after crisis, but was negative in all cases a week later.
The Proportional Frequency of General Paralysis of the Insane and Locomotor Ataxia in Different Social Classes
Authors: McKinlay Peter L.
Published: May 2009

In both of these diseases, locomotor ataxia and general paralysis of the insane, the necessary antecedent is now generally recognised as syphilitic infection. Whether these two types of nervous degeneration occur at random in those so predisposed to their development, or whether some underlying factors at present unknown or only suspected operate selectively is a problem of some importance.
The Antigens of the Cholera Group of Vibrios
Authors: Gardner A. D. , Venkatraman K. V.
Published: May 2009

1. Previous work on the antigenic structure of the cholera group of vibrios is experimentally reviewed, and the data amplified and systematised.

2. The cholera group is defined as consisting of vibrios with similar biochemical characters and having a common heat-labile antigenic component.

3. The heat-stable antigens are divisible into:

(a) A considerable number of specific antigens, best demonstrated by O sera and H-O suspensions, which serve as a basis of classification into O subgroups.

(b) A non-specific component, demonstrable with O sera and O suspensions.

4. The first subgroup contains all the standard cholera vibrios from central laboratories, and the majority of other epidemic strains. We consider that it represents the only class of vibrios known for certain to cause epidemic cholera.

5. The races of this subgroup I are further divisible into two (or perhaps three) “types”, as established by Japanese workers, according to differences in their subsidiary O antigens.

6. The haemolytic “El Tor” vibrios are serologically diverse. The term “El Tor” should, as Shousha suggests, be reserved for those that have the same specific O component as the standard cholera vibrios.

7. For the identification of the undoubted cholera vibrios a standard subgroup I O serum is recommended in conjunction with the haemolytic test. The serum should contain both the main and the subsidiary antigens of the subgroup.

8. As a working rule it is suggested that bacteriological proof of “cholera” or a cholera carrier should rest on the isolation of a non-haemolytic vibrio with the specific O antigen of subgroup I.

The studies and observations on which this paper is based were conducted while one of us (K. V. V.) was holding a Fellowship of the International Health Division of the Rockefeller Foundation.

Our thanks are due to Mr P. Bruce White for constant help and advice, and to the numerous bacteriologists in various lands who have kindly supplied us with cultures and sera.
Prevention of Compressed Air Illness: Obsolete Statutory Regulations as an Obstacle to Progress
Authors: Boycott G. W. M.
Published: May 2009

About 25 years ago Dr J. S. Haldane, Dr A. E. Boycott and Capt. Damant, R.N., in the course of investigations for the British Admiralty, worked out a system of decompression for divers and compressed air workers. This system was adopted by the Admiralty, and by its use compressed air sickness has been practically eliminated entirely amongst naval divers. The system has become known as stage decompression, although in fact stages are not an essential feature of it, though a convenience in practical working. The system has been frequently and fully described. The latest explanation will be found in the last edition, 1935, revised by Haldane and Priestly, of Respiration, by J. S. Haldane (Clarendon Press). Its most essential feature is that the pressure is lowered quickly to approximately half the absolute pressure during decompression, and one of the most important assumptions for working out the decompression tables is that different parts of the body saturate and desaturate at different rates. Enquiries sent out by me during 1934 to the United States, the principal countries of Europe and to Japan indicate, so far as definite information has been received in reply, that stage decompression has been universally adopted for divers, but in no case has it been adopted for caisson and tunnel workers in countries where State regulations already existed, except in a modified form, and I conclude that the reason for this failure to adopt stage decompression is the existence of statutory regulations, either still in force, or only partly modified in accordance with new ideas.
Enzootic Psittacosis Amongst Wild Australian Parrots
Authors: Burnet F. M.
Published: May 2009

1. Psittacosis infection is enzootic amongst several of the common species of Australian parrots in the wild state. A large proportion of recently caught individuals ofPsephotus haematonotus, Trichoglossus(two species) andLeptolophus hollandicusare infected. In other genera, demonstrable infection is rare, but enlarged non-infective spleens probably indicative of past infection are common.

2. The virus strains derived from wild Australian parrots appear to resemble closely those isolated from human and parrot infections in Europe and America.
An experiment on the nutritive value of winter-produced “summer” milk
Authors: Drummond J. C. , Singer Eleanor , Watson S. J. , Ferguson W. S. , Bartlett M. S.
Published: May 2009

1. Two herds of cows were divided into two groups for winter feeding. One group was given the usual ration of hay, roots and “concentrates”, the other was fed on a similar diet in which part of the hay and concentrates was replaced by artificially dried grass.

2. The carotene content of the butterfat in the control group fell steadily from 0·8 mg. per 100 g. of fat to about 0·2 mg. between October and March. That of the group to which dried grass was given did not fall below 0·5 mg. per 100 g. of fat.

3. The milks from the two groups were employed in a nutritional investigation on the boys of two institutions. During a “fore-period” from July until the end of September, the boys received the ordinary milk of the herd as part of their diet. They were then divided into two groups which, during the experimental period from October until March received the “winter” or the dried grass “summer” milk respectively. Then followed an “after-period” during which all the boys received the mixed milk of the herds, then out at pasture. The composition of the basal diet of the boys at these institutions was known. Boys attending an elementary school in the vicinity of one institution were also investigated in a similar experiment but no details of their home diet were obtained.

4. Excluding children whose records were incomplete there were 159 in the group on “winter” milk, and 163 in that receiving “summer” milk.

5. Periodically records of height, weight, and chest measurement were made. All the boys were under medical supervision.

6. Statistical examination of the results fails to show that the artificially produced “summer” milk exerted a beneficial effect detectable by the improvement in growth or general condition of health.

7. The most probable explanation is that the basal diets of the two institutions were already adequate in respect to carotene and vitamin A.

8. The variations exhibited by the records of the groups provide another example of the very great difficulty of eliminating or adequately controlling sources of error in a big-scale nutrition experiment of this type.
The Distribution of the Diphtheria Bacillus and the Bacillus of Hofmann in the Throats of “Contacts” and Normal Persons
Authors: Graham-Smith G. S.
Published: May 2009

1. Diphtheria bacilli have been found in a considerable proportion of persons who have come into contact with cases of diphtheria or with other infected persons.

2. Such persons have been shown to be a grave danger to public health, especially when frequenting schools or institutions, and to constitute the usual channel by which the disease is spread.

3. Very satisfactory results have followed on the isolation of convalescents from the disease and of infected “contacts,” where two or more consecutive negative examinations have been required before release.

4. Carefully conducted investigations amongst healthy persons, who have not at a recent date been in contact with diphtheria cases or infected “contacts,” have shown that virulent diphtheria bacilli are very seldom (3 examples amongst 1511 persons) present in the mouths of the normal population. This fact renders the discovery and isolation of infected persons a practicable possibility and offers a fair prospect of discovering and isolating the majority of them in any outbreak.

5. Diphtheria bacilli are usually distinguishable on morphological and cultural grounds, but whenever possible it is desirable that their virulence should be tested.

6. The bacillus of Hofmann is innocuous to man, and is a very common organism in the mouths of the poorer classes. The distribution of this bacillus points to the conclusion that it is carried from mouth to mouth in the same way as the diphtheria bacillus, and therefore its widespread prevalence in schools attended by poorer children is significant, as showing how widely spread and uncontrollable an outbreak of diphtheria may become unless measures are early taken to deal with infected contacts.
The Relation of Sulphur in Lighting-Gas to Air Vitiation
Authors: Haldane J. S.
Published: May 2009

It is matter of common observation that air which is much vitiated by combustion of lighting-gas is distinctly oppressive, apart altogether from the rise of temperature which is always associated with the vitiation. This effect is always very evident if the proportion of CO2 in the air of a room has been raised to 30 or 40 volumes per 10,000 by combustion of gas. Air to which pure carbonic acid has been added in the same proportion has no such effect, however, and is practically indistinguishable from pure air. Deficiency of oxygen to such an extent as occurs in the air of a room is also without sensible effect. In coal-mines, where the air is commonly vitiated to a considerable extent by slow oxidation in the strata, it is, for instance, quite impossible to distinguish by the senses pure air from air containing an excess of 50 or even 100 volumes per 10,000 of CO2, with a correspondingly large deficiency of oxygen. The unpleasantness of air vitiated by combustion of lighting-gas is therefore not due to excess of carbonic or deficiency of oxygen.
The Micrococcus neoformans
Authors: Dudgeon Leonard S. , Dunkley E. V.
Published: May 2009

Owing to the somewhat contradictory results which have been obtained by various investigators as to the nature of the Micrococcus neoformans and the relation which this organism bears to malignant disease, we have thought it advisable to place on record our observations in a large number of cases of carcinomata, sarcomata and certain cases of anaemia which are known to run a fatal course. Doyen (1886), in a preliminary note communicated to the Academy of Sciences of Paris, stated that he had found small spherical bodies in malignant and other growths which he regarded as micro-organisms. In 1902, at the Surgical Congress, at Berlin, he stated further that he had isolated a micro-organism from simple and malignant growths which, when inoculated into animals, gave rise to neoplastic formations. To this organism he gave the name M. neoformans. In his opinion new growths resulted from an infection of the body with this organism. Since then he has published a number of observations showing the beneficial effects which may be obtained by the employment of a vaccine or serum against the M. neoformans in malignant disease.
Experimental Investigations on Framboesia Tropica (Yaws)
Authors: Castellani Aldo
Published: May 2009

1. Monkeys are susceptible to yaws. The skin eruption in the monkeys I have experimented with (Semnopithecus priamus and Macacus pileatus) is, as a rule, confined to the seat of inoculation but the infection is general, as is proved by the presence of the Spirochaeta pertenuis in the spleen and lymphatic glands.

2. Material obtained from persons suffering from yaws and apparently containing Spirochaeta pertenuis only is infective to monkeys.

3. When the Spirochaeta pertenuis has been removed from this material by filtration, the latter becomes inert.

4. The inoculation of blood from the general circulation and blood taken from the spleen of yaws patients into monkeys may give positive results.

5. The inoculation of the cerebro-spinal fluid of yaws patients gives negative results.

6. Monkeys successfully inoculated with yaws do not become immune for syphilis.

7. Monkeys successfully inoculated with syphilis do not become immune for yaws.

8. By means of the Bordet-Gengou reaction, it is possible to detect specific yaws antibodies and antigen.

9. Yaws antibodies and antigen are entirely different from syphilitic antibodies and antigen.

10. The presence of the Spirochaeta pertenuis in monkeys experimentally inoculated, as well as in yaws patients, is practically constant in the unbroken eruptive lesions; the Spirochaeta is frequently present in the spleen and lymphatic glands.

11. Yaws is generally conveyed by actual contact, but under certain circumstances it may be conveyed by flies and possibly by other insects.
On Variation in Weight of Normal Guinea-pigs in relation to the Estimation of Free Diphtheria Toxin
Authors: Craw J. A.
Published: May 2009

In the foregoing paper (p. 512) relationships have been established between loss of weight in test guinea-pigs and dose of diphtheria toxin injected. In connection with the above, the normal increase of weight during the period of observation, the effect of the animal ceasing to eat, or any change of diet, had to be taken into consideration. The following note records observations on normal increase of weight, with constant and variable diet, on healthy animals.
Further Results on the Isolation of Organisms from Faeces by a New Method
Authors: Wordley E.
Published: May 2009

In a previous communication (Wordley, 1921) I fully described a method, introduced by Dudgeon, for isolating organisms from faeces and sputum. The material is dried to a powder and this dried powder spread over convenient culture media. From my observations this method, for faeces, was found to be superior to those generally in use for isolating the dysentery and enterica group of organisms.
The Reliability of the Wassermann Test as Performed by Different Pathologists
Authors: Bigger Joseph W.
Published: May 2009

A considerable degree of uniformity of results of the Wassermann test has been found among five pathologists.

Certain differences (chiefly in the case of weakly positive sera) have, however, been noted. Their main source lies in the use of different methods and not in any lack of personal ability or care on the part of the worker.

It is believed that the number of these could be greatly reduced by adopting a uniform method of performing the test and by standardising the details of the method.

The supply of a standard antigen and haemolysin to pathologists is recommended.
The Anomalous Features of the Dick Reaction
Authors: McGibbon J. P.
Published: May 2009

About one-fourth of the cases in a series of 160 patients suffering from scarlet fever appeared to be Dick-negative in the acute stage of the disease.

Throughout the illness there was a progressive decrease in the number of positives and in the intensity of the reactions, till in the second week two-thirds and in the fourth week nine-tenths of the total cases were negative. Almost 90 per cent, of the original positives showed this characteristic loss of the Dick-positive state. It would appear that this change occurs less readily in young children. Fluctuations in the reaction during the course of the illness are very uncommon, if indeed they occur at all.

Of eleven cases which failed to show the above change two relapsed. In the other 149 cases no relapses occurred.

Pseudo-reactions are uncommon. Two examples have been described. It is suggested that the use of heated filtrate may be unsatisfactory and that the mechanism of these reactions requires further study.

Some of the anomalous features of the Dick reaction have been briefly discussed. In the opinion of the writer these difficulties have been exaggerated, and they do not in themselves form sufficient grounds for concluding that the test is fallacious.

On the evidence at present available one must continue to regard scarlet fever as a specific toxaemia. The allergic conception of the disease is less convincing.
The Precipitation Reaction: Optimal Proportions, Neutrality and Maximal Precipitation in Mixtures of Albumin and Antiserum
Authors: Taylor G. L. , Adair G. S. , Adair Muriel E.
Published: May 2009

Culbertson (1932) has recently described a method for estimating the antibody content of antisera against crystalline egg-albumin. He determined by tests on supernatant fluids the point at which antigen and antibody neutralised each other. At this neutralisation point he found that antigen and antibody combined in a ratio of 1 to 13, and that the amount of precipitate nitrogen was maximal. The ratio 1 to 13, he stated, held for all the precipitates in the post-zone where antibody was in excess.
The Chemistry and Pharmacology of Lathyrus Peas
Authors: Stockman Ralph
Published: May 2009

A watery extract of lathyrus peas and various salts isolated from them exert a marked action on the brain and spinal cord.

The salts are organic and inorganic phosphoric acid compounds, all of them having an essentially similar action, but differing in toxicity and in their local irritating effect.

Moderate doses cause torpor and depression, larger doses clonic-tonic spasms.

The action is probably a direct one and not indirect through causing a drop in the blood calcium.
An Experimental Investigation on the Influence of Emulsions of Oils and Fats on the Lethal Effects of Bacterial Toxins
Authors: Myers G. Norman
Published: May 2009

It is now generally accepted that certain bacterial toxins are able to give rise to fatty degeneration in tissues and may bring about marked changes of this nature in the heart, liver, kidneys and other organs. When a cell is damaged a state of cloudy swelling or of parenchymatous degeneration generally occurs. The fat is distributed throughout the cell as fine globules and the condition is known as fatty degeneration. Numerous workers (see References) are agreed that many toxins, particularly diphtheria toxin, may cause a widespread damage to cells of the body in this way. The processes involved in the deposition of this fat have led to much discussion and speculation, but do not concern us here.
Serological diagnosis of enteric in the inoculated
Authors: Beattie C. P. , Elliot J. S.
Published: May 2009

The introduction of preventive inoculation against typhoid and paratyphoid, and in particular its widespread application during the Great War, caused considerable difficulty in the interpretation of the Widal test. It was often impossible to decide whether the agglutinins demonstrated were due to active infection or to previous inoculation.
On histamine in cotton dust, and in the blood of cotton workers
Authors: Haworth E. , MacDonald A. D.
Published: May 2009

Crystalline histamine picrate and hydrochloride have been prepared from cotton dust. The melting-points and crystalline structure found are in agreement with those obtained by other workers.

The blood histamines in sixty-five card-room workers have been estimated and compared with the figures found in 103 students and eighteen elderly chronic bronchitics. The figures for the three groups are shown in distribution figures, and the card-room workers have, on an average, a higher blood histamine than both groups of controls. It has, however, to be admitted that the differentiation of card-room asthma from other respiratory diseases on the basis of the level of blood histamine cannot be guaranteed in individuals.
The filtration and centrifugation of the viruses of rabbit fibroma and rabbit papilloma
Authors: Schlesinger M. , Andrewes C. H.
Published: May 2009

The diameter of the virus of rabbit fibroma has been estimated by filtration through graded membranes to be about the same as that of vaccinia (125–175 mµ) and by centrifugation to be 126–141 mµ.

That of the rabbit papilloma virus appeared by filtration to be 23–35 mµ and by centrifugation 32–50 mµ.
Physical and emotional periodicity in women
Authors: McCance R. A. , Luff M. C. , Widdowson E. E.
Published: May 2009

1. The day-to-day records over a period of 4–6 months of 167 normal women's physical changes and subjective phenomena have been collected by a new method. These women submitted data from 780 complete menstrual cycles. In addition, a smaller group submitted data which have been used for physical changes only. One woman's individual record of certain phenomena was obtained over a period of 8 years.

2. The average length of the menstrual cycle was 27·8 days with a standard deviation of 3·4 days. Some individual's cycles were characteristically short or long, regular or irregular. No woman menstruated with complete regularity (measured in days) over a period of 6 months. Twenty-three per cent of the menstrual periods began between 7.30 and 9.30 a.m., and the average duration of the flow was about 4·5 days.

3. Records from one case of intermenstrual, probably ovulatory, bleeding were obtained over a period of 6 months (Chart 2).

4. The periodicity of each subjective phenomenon as shown by the combined results has been recorded graphically, and these figures themselves constitute a summary of the results. Thus for fatigue, abdominal pain, backache, headache, breast changes, sexual feeling and intercourse, depression, elation, tendency to cry, irritability, intellectual capacity and tension see Figs. 5–19. Individual data of interest have been discussed in the light of the combined results.
Further researches on bactericidal mists and smokes
Authors: Twort C. C. , Baker A. H.
Published: May 2009

In Out original paper on germicidal aerosols (Twort, Baker, Finn & Powell, 1940) it was shown that the most satisfactory results were obtained with a solution of 10% hexyl resorcinol in propylene glycol together with a little alkali and wetting agent, the mixture being mechanically atomized into mist particles of appropriate size. Although it was confirmed by other workers that a high degree of lethal effectiveness on air-borne bacteria was achieved by the above procedure, objections were raised to its use in practice at the moment on the grounds that:

(1) The germicide base was difficult to obtain.

(2) The solvent was only manufactured in America, and not in bulk there.

(3) The mechanical apparatus advocated involved the use of metals now required for the making of war weapons.
The distribution of the logarithm of survival times when the true law is exponential
Authors: Irwin J. O.
Published: May 2009

In a recent paper Withell (1942) has shown that for a wide range of microorganisms and disinfectants or poisons the logarithms of the survival times are approximately normally distributed. Even when the number of survivors is adequately represented by an exponential function of the time (e−kt) say, the former hypothesis still gives approximately correct results. This suggests that in many cases the data are not good enough to distinguish between the two hypotheses (1) of a constant force of mortality k and (2) of a normal distribution of the logarithms of survival times. It is worth while, therefore, to examine the form of the distribution of the logarithms of survival times when the exponential law is true, and to see how nearly normal it is. We shall show that except for the position of the mean, this distribution is independent of k.
The cultural characters and pathogenicity for some laboratory animals of the vole strain of acid-fast bacillus
Authors: Griffith A. Stanley
Published: May 2009

Wells (1937) discovered that field voles in this country are subject to an epizootic disease due to an acid-fast bacillus. The natural disease in the vole is characterized by the deposition of a cheesy substance in the areolar tissue spaces and the formation in the organs, the lungs particularly, of lesions which have a close resemblance to those of tuberculosis.
The labile antigens of Shigella dysenteriae Shiga
Authors: Shelubsky M. , Olitzki L.
Published: May 2009

Our data suggest that there are four different thermolabile antigens in S. dysenteriae (Shiga) appearing in different combinations in the five variants described. These antigens are:

1. The agglutination-inhibiting factor ‘I’, found in variants 1 and 3, which is a typical surface antigen.

2. A precipitinogen, ‘N’, probably identical with the neurotoxin, found in variants 1, 2 and 5.

3. A labile precipitinogen, ‘A’, in the extracts of variants 1 and 2, occurring in the deeper layers of the bacterial cell.

4. An additional precipitinogen, ‘B’, found in extracts of variants 1, 2, 3 and 4. It differs from the other labile antigens as its combining- and immunizing-powers are not destroyed by heating at 100° C. for 2 hr.
Combined pertussis-diphtheria prophylactic antigens: An experimental study to determine the specific immunizing value of these antigens used in combination
Authors: Ordman David , Grasset E.
Published: May 2009

1. Experiments in laboratory animals are described, which were made to determine the specific antibody production following injections of diphtheria and pertussis antigens separately or in combination.

2. Agglutinins to H. pertussis vaccine were not increased or otherwise changed by combining H. pertussis vaccines with either diphtheria anatoxine or A.P.T.

3. A striking enhancement of diphtheria antitoxin production occurred when diphtheria prophylactics were used combined with pertussis vaccine. Such improvement in antitoxin production was most marked in the case of diphtheria anatoxine, but was also shown following the use of A.P.T. in combination with pertussis vaccine.

4. Diphtheria anatoxine combined with H. pertussis vaccine gave no better antitoxin response than did a.p.t. alone.
Seven-year study of pneumococcus type incidence in the Royal Hospital for Sick Children, Glasgow
Authors: Guthrie K. J. , Montgomery George L.
Published: May 2009

This paper records the results of systematic pneumococcus typing over a 7-year period in children from 4 days to 12 years of age in the R.H.S.C., Glasgow. Strains typed include those from respiratory tract lesions, from pus in middle ears, meninges, joints, serous sacs and miscellaneous purulent foci. A series of strains from normal throats serves for comparison.

The constant prevalence year by year of types 6, 19, 1 and 23 in all types of disease is striking. On dividing the cases into those under and over 2 years, the incidence of type 1 in the older children is four times that in the younger group. Conversely in those over 2 the incidence of the higher types (21–32) is only half that in the younger patients. No other significant difference in type distribution is observed on comparing the two age groups. Group IV pneumococci are commonly carried in the healthy nasopharynx, and are potential pathogens in young children in whom broncho pneumonia is generally an endogenous infection. There is evidence that the same type of pneumococcus frequently invades the entire respiratory tract and the middle ears. Only thirty of our cases were in the neonatal period and the apparent immunity of the newborn to the pneumococcus is discussed.
Submarine escape breathing air
Authors: Donald Kenneth W. , Davidson W. M. , Shelford W. O.
Published: May 2009

Recent research has even further emphasized the physiological dangers to which man is exposed when breathing gases at increased tensions. If he breathes air his activity under water is greatly limited by the problems of supply and compressed air illness. The latter is due to the formation of bubbles of nitrogen in the body on return to normal atmosphere. If he breathes oxygen, then he is in grave danger of oxygen poisoning, with convulsions, even at relatively shallow depths (Donald, 1947). During the recent war, mixtures of nitrogen and oxygen were employed for important work where the diver wished to go to considerable depths while carrying his own gases. These mixtures were varied in composition and rate of supply so that oxygen poisoning was avoided, and immediate rapid surfacing was possible, without compressed air illness occurring. However, this ingenious compromise is limited in its application, for as greater depths are reached, the oxygen has to be greatly reduced to avoid convulsions. The resultant rise in the proportion of nitrogen being breathed causes bubble formation in any but the shortest exposures. It is to be doubted whether the maintenance and meticulous supervision required, when using mixtures, will allow the use of these in the more normal conditions of peace-time. It has become increasingly apparent that the prolonged underwater survival of men requires pressure-withstanding devices in which he can exist at normal physiological tensions, i.e. atmospheric pressure. The rigid diving suit and submersible chambers, such as the bathysphere, are in their infancy; but the submarine, where the same conditions apply, is now a highly successful and developed method of underwater existence and locomotion. The further evolution of these devices, and of the submarine, depends mainly on engineering advances and not upon attempting to extend the comparatively rigid limits imposed by human physiology. The maintenance of a healthy atmosphere within a submarine is again a chemical and engineering problem which is capable of solution and constant improvement.
Temporary and chronic carriers of Salmonella typhi and Salmonella paratyphi B
Authors: Vogelsang Th. M. , Bøe Johs
Published: May 2009

1. In a material consisting of 417 cases of typhoid fever and 1055 cases of paratyphoid B investigated over a period of 28 years, infection with S. typhi was found to be considerably more serious than infection with S. paratyphi B. In childhood and among young folk the S. paratyphi B mortality was low, but in the age group over 30 it reached 5%. But even in childhood infection with S. typhi gave a mortality of 8·5%, rising at a higher age to 16%.

2. Of the 1387 patients surviving the infections 13·3% were found to be excreters during convalescence, 11% being temporary and 2·3 % being chronic carriers.

3. Of the temporary carriers, 7·9% were faecal and 3·7 % were urinary carriers. The percentage of temporary excreters was approximately the same for the typhoid and paratyphoid B patients—40% were men and 60% were women. The number of temporary carriers rose with the patients' age, and in the age group over 30 years, about 15% were temporary carriers in the case of both infections.

4. Of the temporary carriers, only one-tenth discharged the specific germ for more than 4 weeks after the cessation of the illness. After an interval of 3 months, it is most exceptional for the carrier state to cease spontaneously. We may, therefore, feel justified in fixing this interval as the dividing line between the temporary and the chronic carrier state.

5. Of the typhoid patients 3·3%, and of the paratyphoid B patients 1·9%, became chronic carriers. Thirty-one of them were faecal and only one was a urinary excreter. There was only one child found to be a chronic typhoid carrier. Chronic carriers were also rare among young folk, and the incidence of this state rose much with age, as many as twelve of the total of thirty-two chronic carriers being over the age of 50. Eleven of these twelve were women, five being typhoid and six being paratyphoid B carriers.

6. Most of the chronic carriers have been kept under control for a long time. The only chronic typhoid carrier to recover spontaneously was a woman, aged 52. Cholecystectomy was performed on fourteen chronic carriers. In all the cases in which the carrier state had lasted for at least a year, gall-stones and chronic cholecystitis were found, and the specific germ was obtained in pure culture from the gall-bladder. A woman who had continued to discharge S. typhi for more than 1½ years after the operation, ceased to do so after this interval. The object of the operation was not achieved in one case.
Notes on climate and morbidity
Authors: Parnell R. W.
Published: May 2009

Opportunity was taken to study the morbidity of the more important groups of diseases affecting R.A.F. personnel with reference to the climatic conditions at Mingaladon, nr Rangoon, from February to July 1946. Temperature recordings (both wet and dry bulb), together with figures for humidity, were kindly provided by the Meteorological Forecast Centre at the station. The climatic conditions may be divided into two distinct periods: the pre-monsoon from mid-February to mid-May, and the monsoon itself which followed and continued throughout June and July.
Experiments on adaptive variation and rejuvenation:Bacillus dysenteriaeFlexner, grown on media containing sulphanilamide, acriflavine, argyrol, neosalvarsan and no drug
Authors: Stewart F. H.
Published: May 2009

Bacillus dysenteriaeFlexner(Shigella paradysentriae)grown on Lemco agar plates (without peptone) containing sulphanilamide 1/20,000 to 1/10,000 forms papillae which on subculture yield two strains: (1) the original strain unmodified and (2) a strain resistant to SA.

The latter has arisen by discontinuous variation. There are no forms intermediate between strain (1) and strain (2).

In one such case (Exp. 1, p. 334) the no-contact race, the unmodified non-resistant strain from the primary sulphanilamide plate and the resisting variant strain were titrated in broth containing sulphanilamide in ten increasing concentrations from 1/34,000 to 1/5000. The first two strains, the no-contact and the unmodified non-resistant from the sulphanilamide plate grew in SA 1/34,000 and failed in 1/21,000, while the resisting variant grew up to the tube containing SA 1/6000 and failed to grow in 1/5000.

On plates containing sulphanilamide this adaptive variation takes place only in the papillae. It can also take place in broth containing, for example, SA 1/20,000 to 1/10,000.

There is no such thing as gradual progressive acquisition of resistance by the whole of a bacterial population exposed to a drug. Such phrases as ‘teaching bacteria to resist’ are misleading and anthropomorphic and should not be employed.

Fluid cultures which show a progressive gradual increase of resistance do so as a result of an increasing percentage of resistant cells in a mixed population of resistant and non-resistant bacteria. Experiments in fluid media should always be checked and the growth analysed by plating.

Resistant strains maintain this character after prolonged growth on drug-free media.

(2) Flexner's dysentery bacillus grown on plates containing acriflavine 1/60,000 to 1/40,000 forms in papillae strains resistant to this drug. The non-papillary areas of colonies die early, viz. on the 3rd day. The variation in this case also is discontinuous.

(3) On the other hand, if Flexner's bacillus is grown on agar containing organic compounds of silver or arsenic (argyrol or neosalvarsan), it forms no variants resisting these drugs.

(4) Papillae possess two biological functions:(a)they are the site of adaptive variation in response to elements in their environment, such as harmful drugs or useful sugars; (6) they are also the site of rejuvenation of senile cells and of cells affected by common unfavourable conditions such as exhaustion of food supply and accummulation, of excretory substances.

The greatest development of papillae takes place on plates which form no variants, such as plates of drug-free agar, agar plates containing sulphanilamide sown with strains resistant to sulphanilamide and plates containing organic compounds of silver or arsenic.
The survival of foot-and-mouth disease virus in meat and offal
Authors: Henderson W. M. , Brooksby J. B.
Published: May 2009

Quantitative studies have been made of the survival of foot-and-mouth disease virus in beef and beef offals after storage at temperatures employed in the imported-meat trade.

The survival of virus is closely associated with the hydrogen-ion concentration of the tissue; thus the acidity of rigor mortis of muscular tissue rapidly causes inactivation. Quick-freezing of beef suspends acid formation and active virus was demonstrated for so long as the meat was kept frozen.

Thawing of quick-frozen meat initiates the suspended acid formation at an accelerated rate and rapidly produces a medium unsuitable for virus survival.

Liver, kidney, rumen, lymph node and blood from diseased cattle have all been shown to be highly infective and to remain so if stored frozen. Acid formation in these tissues and in blood is not on the same scale as in muscle, and prolonged survival of virus is more likely even with delay in freezing and after thawing. This remains true of lymph node and of residual blood in vessels of a carcass in which the development of rigor mortis is complete.

Feeding of infective offal to swine under experimental conditions resulted in the appearance of the disease.

The significance of these observations is discussed in relation to the distribution of these products constituting a risk of spreading foot-and-mouth disease.

We are indebted to Dr Ian A. Galloway, Director of this Institute, Mr L. B. A. Grace, Chief Technical Adviser on Meat Inspection of the Ministry of Food and Mr R. Bremner, Chief Executive Officer of the Meat Importers' National (Defence) Association, Ltd., for their help and advice while this work was in progress.

It is a pleasure to acknowledge the technical assistance of Mr W. J. Brownsea.
Evaluation of methods of applying oil to bedclothes and practical application of the selected method
Authors: Leslie R.
Published: May 2009

Thomas & Van den Ende (1941) and Puck and his collaborators (Puck, Hamburger, Robertson & Hurst, 1945; Puck, Robertson, Wise, Loosli & Lemon, 1946) have shown that the application of small amounts of oil to bedclothes reduces the quantities of dust and bacteria liberated during bedmaking. Joyce Wright in her first investigation (Wright, Cruickshank & Gunn, 1944) found that oiling bedclothes was, consequently, effective in reducing the incidence of cross-infection, but this was not confirmed in her later work (Wright, Begg & Smellie, 1947), or by Krugman & Ward (1951). Barnard (1952), however, has recently shown that cross-infection can possibly arise by interchange of bacteria in blankets during laundering. Oiling of bedclothes may, therefore, be a very useful hygiene measure.
The antibody response in man following infection with viruses of the pox group I. An evaluation of the pock counting method for measuring neutralizing antibody
Authors: McCarthly K. , Downie A.W. , Armitage P.
Published: May 2009

Various techniques have been used in studying antibody responses following infection with pox viruses. Ofthe in vitrotests the complement fixation and haemagglutination inhibition techniques have proved most convenient, but the antibodies concerned are apparently diiferent from neutralizing antibody (Chu, 1948). Estimation of this antibody to certain members of the group, such as ectromelia and vaccinia viruses, may be made in susceptible animals. Variola virus does not, however, produce lesions in the common laboratory animals with sufficient regularity to make such neutralization tests practicable. But it does constantly give rise to recognizable focal lesions on the chorio-allantois of developing chick embryos. This tissue, susceptible to most members of the pox group, has therefore been used in previous studies (McCarthy & Downie, 1948; Downie & McCarthy, 1950), employing the technique developed by Burnet and his colleagues for vaccinia and other viruses (Burnet, 1936; Keogh, 1936; Burnet, Keogh & Lush, 1937; Burnet & Lush, 1939).
An Improved Assay for the Infectivity of Influenza Viruses
Authors: Fazekas de St Groth S. , White D. O.
Published: May 2009

The standard tests for infectivity of influenza viruses in eggs or mice have two major shortcomings. First, the host systems are known to be inhomogeneous, i.e. the response does not depend solely on the dose; and second, this variation from host to host cannot be assessed independently, since a single test only can be made on any one egg or mouse. Thus, the two probabilities—the presence of an infective unit in the inoculum and the success of a particular virus-host interaction—are confounded, so that we estimate not the number of infective units but an unknown function of this number. Valid comparisons of infectivity can still be made as long as one is satisfied with a relative answer, and does not wish to inquire into the nature of host-resistance.