bluuebunny/crossref_metadata_2025 huggingface dataset:
Further Observations on the Occurrence of Iodine in Relation to Endemic Goitre in New Zealand and on Iodine Metabolism
Authors: Hercus C. E. , Aitken H. A. A. , Thomson H. M. S. , Cox G. H.
Published: May 2009

1. Most artificial manures are found to have some effect in increasing the iodine content of crops, particularly superphosphate.

2. Marked differences are found between the iodine contents of Samoan and New Zealand foodstuffs corresponding to the non-goitrous condition of Samoa and the partial endemicity of New Zealand.

3. Investigation of the dietaries of fifteen residential institutions showed that improvement in provision of iodine was necessary in many cases by using fish at least twice a week, raising the daily ration of milk to 1 pint per head, and employing iodised salt for table and culinary purposes.

4. Dietetic experiments indicate (i) that on a change of diet adjustment of iodine metabolism may take a considerable time, (ii) that iodised salt is most effective in promoting storage of iodine when associated with a meat diet.

5. Iodine excretion is found to decrease much more rapidly under fasting than on a diet very low in iodine.

6. Iodised salt has the effect of adjusting the excretion of goitrous adults to the normal non-goitrous value.

7. The iodine content of the blood is found to be lower than normal in cases of simple colloid and simple nodular goitre, though it may range from low to abnormally high in cases of Graves' disease. In all types of goitre the thyroid gland is low in iodine.

8. The ratio of thyroid iodine to total bodily iodine is about 12 per cent. in the case of the white rat under ordinary conditions, but the ratio is found to vary considerably with the iodine intake.

9. Great differences in the ratio of the weight of the thyroid gland to that of the whole body are found among different species of animals, the ratio being higher for the dog than for the monkey.

10. Variations in commercial samples of iodised salts are recorded and discussed.

11. Data are given in regard to the iodine and chlorine content of rainwater in different localities.
Cancer and Syphilis
Authors: Evans Griffith
Published: May 2009

The object of a paper by Fry (1930, p. 313)1 was “to ascertain…the relation of syphilis to malignant disease as determined by the Wassermann reaction.” The conclusion reached (p. 322) was: “In general, from the above figures, there is no evidence that syphilis plays any direct or very important part in the production of cancer.”
Prophylactic Vaccination in Epidemic Meningococcal Meningitis
Authors: Riding D. , Corkill N. L.
Published: May 2009

1. An epidemic of meningococcal meningitis, due to Type II meningococcus, occurring in a large native population is briefly described.

2. A method of preparing prophylactic meningococcal vaccine on a large scale, and its experimental application in the epidemic is demonstrated.

3. The results obtained in two similar groups of natives, one inoculated with meningococcal vaccine and the other with T.A.B. vaccine, as to the incidence of, and death rate from, meningococcal meningitis are detailed.
Combining Affinities in Bacterial Variation and Carcinogenesis
Authors: Eastwood Arthur
Published: May 2009

Although knowledge of principles determining variation is imperfect, some progress has been made and further help may be obtained from some of the newer conceptions about combining affinities regulating normal growth. There are reasons to believe that growth depends on a rhythmic cycle of synthesis, peculiar to living protein, whereby at each successive stage one particular “building stone” is selected for synthesis, with rejection of all others. There is also some evidence that the surface of a growing bacterium passes through periodic phases. Additional light on the activities of the bacterial surface is thrown by the new conception of enzymes which regards them not as fixed chemical entities but as chemico-physical “centres of activity.”

Some of the principles which are gradually coming to light in bacterial variation may ultimately be of assistance in the much more obscure problem of explaining the change from the normal mammalian cell to its malignant variant. I refer in particular to conceptions, which I have discussed in the preceding part of this article, about the mechanism of cellular growth and the nature of a cell's combining affinities.
Brucella abortus in Milk
Authors: Smith J.
Published: May 2009

As a result of the extensive investigations in America and on the Continent into the relationship of Br. abortus to undulant fever in man, attention in this country has been directed to cases of fever due to obscure causes, with the result that an increasing number of cases of undulant fever are being reported. So far, however, the cases in Great Britain appear to be less numerous than those in the United States and in Denmark where every effort has been directed to tracing sources of infection and where the conclusion has been reached that, although a certain number are infected by contact with the secretions and carcasses of infected animals, many infections occur through ingesting milk containing Br. abortus.
Granular “O” Agglutination in Paratyphoid B and Typhoid Fevers
Authors: Gardner A. D. , Stubington Edith F.
Published: May 2009

The granular “O” agglutination of human serums from eighty cases of typhoid and paratyphoid B fevers has been titrated with carefully selected killed typhoid “O” and paratyphoid B “O” suspensions of high sensitiveness.

In spite of a wide overlapping, due to common factors, a considerable specificity is shown, and this can be utilised in differential diagnosis, especially if due attention is paid to the different levels of “normal” agglutination for the two species.
Cancer Susceptibility in Relation to Colour of Mice
Authors: Twort C. C. , Twort J. M.
Published: May 2009

An examination of some 10,000 tumour-bearing mice appertaining to 240 experiments comprising 24,000 animals has been made to find whether there was any difference in sensitiveness of the skin to our carcinogenic agents, according to colour of coat and eyes. Methods involving only elementary arithmetic have been utilised as we have, unfortunately, no statistical mind on our staff, and thus we have, presumably, failed to derive full benefit from the data available. We have ventured, however, to draw the following tentative conclusions as regards the particular animals under discussion, they being obtained from varied sources:

1. Self-coloured animals (excluding pure white) were more sensitive to petroleum oils (weak agents) than the corresponding piebald. (That is, a black was more sensitive than a black and white, etc.)

2. When tars (strong agents) were utilised instead of petroleum oils an opposite state of affairs existed, the self-coloured animal being more resistant than its piebald companion. This reversal may be explained on the grounds of cell tolerance.

3. Pink-eyed animals (excluding pure white) had a greater all-over sensitiveness of the skin to our agents than pigmented-eye animals.

4. On the whole the most sensitive animal was the pink-eyed fawn.

5. The frequency of hyaline degeneration of the spleen and marked thyroid enlargement was greater among pink-eyed animals, especially when fawn coloured, than among pigmented-eye animals.
The Bacterial Purification of Gasworks' Liquors. The Action of the Liquors on the Bacterial Flora of Sewage
Authors: Happold Frank Charles , Key Arthur
Published: May 2009

A study has been made of the bacterial flora in the sewage supplied to, and the effluent from, the bacteria beds which deal with the liquors produced at the Coventry gasworks. A high count in the effluent from the beds of bacteria containing an oxidase system, or a relatively large increase in the viability of such organisms when compared with the original sewage, has been found to be concurrent with good purification in the beds, and vice versa.

The bacterial flora undergoes considerable modification in the beds, and also when mixed with 4 per cent, of its volume of spent liquor in the laboratory. The total viable count of the treated sewage is reduced under these conditions, but the count of those bacteria which give the direct oxidase reaction and therefore catalyse the oxidation of catechol is relatively increased.

A gram negative vibrio (strain 0 1) is the only bacterium isolated which has proved capable of breaking down monohydric phenols. It has been constantly isolated from the effluent liquors.

Gasworks' ammonia liquor in the relatively high concentrations used exerts a markedly toxic action on all types of sewage bacteria, and the purification of this liquor by the beds is not so satisfactory. The toxicity is probably caused by the highly alkaline reaction of the liquor.

This investigation was commenced by one of us (F. C. H.) in conjunction with Dr Allan C. Monkhouse, who was at the time Research Chemist to the Liquor Effluents Sub-Committee of the Institution of Gas Engineers. Dr Monkhouse accepted another appointment shortly after the commencement of the work, and was therefore unable to assist further, but we should like to express our indebtedness to him during the initial period. We are also indebted to Prof. J. W. McLeod and Prof. J. W. Cobb for their kindly interest and encouragement, and to Mr P. N. Langford, Engineer and Manager of the Coventry Gas Department, for the facilities he so generously placed at our disposal at Coventry.

One of us (F. C. H.)is in receipt of grants from the Medical Research Council, and would again express his thanks to that body.

One of us (A. K.) is indebted to the Liquor Effluents and Ammonia Sub-Committee of the Institution of Gas Engineers for permission to publish this work.
On the Use of a Pressure Steam Disinfector for Disinfestation and Disinfection, by Dry Heat and/or Gaseous Disinfectants
Authors: Langrishe J. du P.
Published: May 2009

1. An investigation has been carried out, with, a view to determining (a) whether articles liable to damage by steam can be disinfected and/or disinfested in a standard steam pressure disinfector by the action of dry heat and/or gaseous disinfectants; (b) the economic practicability of the method.

2. Lice and bugs can be thus easily destroyed in loosely suspended articles by dry heat at 55°C. acting for 30 min., the total time occupied being one to one and a half hours, depending on the size of the charge.

3. Infective material (non-sporing organisms), including tuberculous sputum, in loose articles, can be disinfected by penetration of dry heat at 50°C. followed by formaldehyde, 5 per cent, (approximately), allowed to act for one hour, the total time not exceeding two and a half hours. Organisms, other than tuberculous sputum, can be disinfected by exposure for 30 min.

4.(a) Rubber, leather, imitation leather, furs, silks and woollens are not injured by this method.

(b) Blood-stains are fixed by the action of the formaldehyde, but not by dry heat alone.

5. The method is not suited for the disinfection of large bulky articles containing much entangled air.

6. Infective material cannot be rendered sterile, and lice are not killed, by exposure to formaldehyde, 7 per cent. (approximately), for one hour at room temperature.

7. It required an exposure of four hours at room temperature to a concentration of sulphur dioxide beginning at 4 per cent. and falling to 0·75 percent., in order to kill lice and bugs and to sterilise B. typhosus in exposed situations; but even this was ineffective where such were embedded in a piece of flock mattress.

8. Contact with dry heat at 55°C. for one hour cannot be relied upon to sterilise infective material.
Milk Pasteurisation as a Technical Problem
Authors: Savage William G.
Published: May 2009

One of the difficulties in the way of recommending pasteurisation as a general measure for the protection of the milk supply is the fact that as a technical process it is not completely satisfactory, or perhaps better stated, that there are many loopholes for faulty practice. The problems of pasteurisation are not solved merely by enunciating that scientific investigations under laboratory conditions show that certain time-temperature factors are capable and requisite to kill all pathogenic bacteria in milk and that in the process the damage to the milk is neither material nor detrimental. The application of these time-temperature factors under working conditions involves consideration of a number of practical problems. If we are to adopt pasteurisation as a regular part of Public Health practice it is essential to consider these problems and to make the procedure as technically perfect and satisfactory as possible. Any trade objections have to be considered and weighed and, if they are of substance, removed, if that can be done without harm to essential requirements. This is important, since demands which cut across trade needs are likely to be evaded or at least carried out in a lukewarm fashion.
The Influence of Static Effort on the Respiration and on the Respiratory Exchange
Authors: Bedford T. , Vernon H. M. , Warner C. G.
Published: May 2009

(1) The energy cost of static effort.

From previous work it appears that the metabolic cost of maintaining a given tension varies directly as the load, provided no new muscles are brought into play as the result of fatigue or local strain. There is conflict of opinion as to the relation of cost to tension; some workers find a linear relation, while others find a non-linear one.

In the present observations contractions, which were virtually isometric, were made against a powerful spring, while in a standing position.

With constant tension the oxygen cost per contraction varied directly as the duration of the contraction. With constant time and increasing tension the oxygen cost increased more rapidly than the tension.

The duration of contraction varied from ½ to 30 sec., and the tension from 30 to 165 Ib. Over the whole range the oxygen cost per contraction is adequately described by the equation

Q = T1·37 (0·0117 + 0·01090t),

where Q is the oxygen cost per contraction, T is the tension, and t is the duration of contraction.

(2) The effect of static effort on the respiration.

As a measure of hyper-ventilation the ratio of ventilation to oxygen intake is used. It is shown that in dynamic work this ratio falls below the resting value, whereas in static effort of whatever severity the ratio increases considerably above the resting value if the effort is sufficiently prolonged. The rise in the ventilation ratio runs parallel with the feelings of strain which are associated with static effort. Pain causes such a rise in the ratio, and the rise which occurs in static effort is ascribed to the influence of painful sensations of strain.

Observations were made in which the posture alternated between sitting and standing every 40 sec. The change of posture altered the distribution of the strain, and thus the subjective sensations were not so marked as in the experiments with posture unchanged. In consequence of the postural change the ventilation ratio did not rise sensibly above the resting value, and the maximum strength of pull was increased by 6–16 per cent.
The Bacterial Flora developing on Stored Lean Meat, especially with regard to “Slimy” Meat
Authors: Haines R. B.
Published: May 2009

1. Examination of the “slime” obtained on lean beef stored at temperatures just above zero Centigrade has shown it to be composed chiefly of organisms of theAchromobactergroup.

2. A study of about 120 strains of these organisms has been carried out and the characteristics of typical strains are given in detail.

3. Data of the rate of growth of these organisms on meat and in broth are given.

4. The dependence of the “storage life” of the meat on the initial bacterial load is shown.
The bacteriophages ofPseudomonas aeruginosaFiltration measurements and electron microscopy
Authors: van Den Ende M. , Don Phyllis A. , Elford W. J. , Challice C. E. , Dawson I. M. , Hotchin J. E.
Published: May 2009

Preliminary observations in a systematic study of fifteen bacteriophages isolated fromPseudomonas aeruginosaare described. The evidence as to size, morphology and plaque appearance indicates that this group of phages comprises several distinct types. The electron microscope reveals some of the phages to be simple spheres, but the majority are tailed particles.

The importance of this group in the study of the phenomenon of lysogenicity is pointed out.
A wind tunnel for the study of airborne infections
Authors: Druett H. A. , May K. R.
Published: May 2009

A vertical closed circuit wind tunnel is described in which a spinning top sprayer is used as a source of homogeneous particles of pathogenic organisms. The dry particle size may be set at any figure between 1 and 20 µ, and the cloud concentration can be varied over wide limits. Provision is made for humidity control. Animals may be exposed to the cloud, and samples taken from it. The apparatus can be sterilized with flowing steam and formalin.

An appendix giving details of the operational technique is available on request.
Hexylresorcinol as an aerial disinfectant
Authors: Mackay Ian
Published: May 2009

Experiments were carried out in a test chamber of 16,500 cu.ft. capacity with air conditioned at 68° F. and 54% relative humidity. Ventilation was controlled at 3·0 changes/hr., air being recirculated with 0·5 air change/hr. of fresh air admitted. By spraying into the air ducting a concentrated suspension of Chr. prodigiosum a bacterial cloud was introduced into the chamber of over 5 × 106 organisms/cu.ft. of air as l μ particles. Viable organisms were still present in the atmosphere after 6 hr.

When a heat-generated vapour of hexylresorcinol was introduced in a concentration of between 6 and 7 μg/cu.ft. of air the bacterial count dropped from nearly one million organisms per cu.ft. to fewer than ten in 35 min.

When the bacterial suspension was sprayed into the chamber with hexylresorcinol vapour present, the peak concentration reached was about one-quarter and on stopping the spray, the bacterial count fell from one million per cu.ft. to fewer than ten in less than 25 min.

Hexylresorcinol is also effective when the bacterial aerosol is in particles of 6–7 μ in size (approx. 100 bacteria per particle).

Hexylresorcinol has no effect against a bacterial aerosol of B. subtilis spores in 1 μ particles.

No attempt has been made to analyse the mode of action of hexylresorcinol in diminishing the bacterial content of the air. The evidence collected clearly indicates the necessity for further study of this problem.
Diphtheria anti-gravis serum: its action on experimental infection and in the treatment of patients
Authors: Maitland H. B. , Marshall F. N. , Petrie G. F. , Robinson D. T.
Published: May 2009

Antibacterial sera against C. diphtherias gravis (serological type I), intermedius and mitis were prepared in horses. The details of the immunization and the preparation of the sera are described. The sera contained a minimal amount of antitoxin.

The anti-gravis serum in the dose used, when it was given to guinea-pigs 1 hr.before the subcutaneous injection of ten lethal doses of the homologous organism, saved the life of 75 % of the animals. Those which died lived longer than the controls, and C. diphtheriae was recovered less often from the local lesion and the liver than at the same sites in the controls; it was not recovered from the heartblood of the animals which received the experimental serum, whereas cultures from the heart-blood were positive in about 40 % of the controls.

In these experiments the degree of invasiveness of the strain, as judged by the frequency of its recovery in cultures from the heart-blood and the liver of the control animals, corresponded with earner observations (Robinson & Marshall,1934), which showed that in routine virulence tests carried out by the subcutaneous inoculation of guinea-pigs C. diphtheriae could often be cultivated from the local lesion, the liver, the pleural fluid and the heart-blood, and that gravis and intermedius strains were more invasive than mitis strains. This was one of the main facts which suggested that an antibacterial factor might prove to be a useful adjunct in the treatment of diphtheria.

The anti-gravis serum, when given as a supplement to the routine doses of antitoxin to patients with severe diphtheria, had a definitely beneficial influence on the local lesion. Moreover, the serum improved for a time the general condition of some of the patients, including those who died later. The death rate of the group to which anti-gravis serum was administered was similar to that of the control group but, on the other hand, the patients who received the serum lived, on the average, longer than the control patients notwithstanding that treatment of the former group was begun later in the disease. The clinical evidence in favour of the anti-gravis serum cannot be assessed quantitatively, but, since it is based on critical observations, it should not be disregarded.

Consideration of the results as a whole leads us to conclude that the anti-gravis serum used in the tests contained a specific antibody which, within limits, had a beneficial action. We suggest, therefore, that the role of the antibacterial factor in the pathogenesis and control of diphtheria merits investigation.
The effect of storage on the coliform andBacterium colicounts of water samples. Overnight storage at room and refrigerator temperature
Authors:   The Public Health Laboratory Service Water Sub-committee
Published: May 2009

This investigation has been concerned with the changes that occur in the coliform and faecalcolicontent of water samples on storage at room and refrigerator temperature for 20–24 hr.

On examination by a seventy-tube method, using twofold diminishing volumes, twenty-three out of 151 samples of water stored overnight at room temperature showed a significant increase in the presumptive number of conform organisms and twenty-nine a significant decrease. Of the same number stored in the refrigerator, ten showed a significant increase and twenty-six a significant decrease.

Of 111 samples examined for faecalcoli, eight showed a significant increase on storage at room temperature and twenty-nine a significant decrease. Of the same number stored in the refrigerator, seven showed a significant increase and fifteen a significant decrease. The effects of the source of the water, the time of year and the original number of coliform organisms in the sample were examined.

The present investigation has shown that in a considerable proportion of samples a significant change in the conform and faecalcolicontent does occur on overnight storage at room or refrigerator temperature. It may, perhaps, be safe to store samples under some conditions for shorter periods, but this is a matter for future investigation.
Estimation of LD50 by moving averages
Authors: Bennett B. M.
Published: May 2009

Methods of graduation of a series of observations by means of moving averages were discussed by Sheppard (1914), and subsequently by Sherriff (1920) and a number of other writers. These methods based on least squares or weighted least squares solutions differ from actuarial or summation methods. Thompson (1947) has proposed that the method of moving averages be considered a ‘basic’ one in the estimation of the median effective dose (LD50) of bioassay data. On the basis of an empirical study of the data of Topley and Wilson he recommended in particular the use of a three-term moving average. In a recent paper, Finney (1950) has discussed the efficiency of Thompson's moving average method generally.
A Comparison of different routes of inoculation of cattle for detection of the virus of foot-and-mouth disease
Authors: Henderson W. M.
Published: May 2009

Intradermal inoculation of the tongue, subcutaneous, intracutaneous and intra-venous inoculation were compared in determining the relative facility with which foot-and-mouth disease infection can be produced in cattle.

In seven experiments using six virus strains, least virus was required to infect by the intradermal tongue route, but wide variation was observed between the amount of virus required to infect by this route and by the subcutaneous, intracutaneous or intravenous routes. The smallest difference between tongue and subcutaneous inoculation was not significant, and the largest difference was that 250,000 times more virus was required to infect by the subcutaneous route. The readiness with which infection is produced by routes other than intradermal inoculation of the tongue may be greatly influenced by the strain of virus used.

Intranasal instillation of the virus was also compared with intradermal tongue inoculation. As with subcutaneous inoculation, more virus was required for infection by the intranasal route and, similarly, the results suggest that considerable variation would be found in the amount of different strains required.

A correlation is suggested between this variation and the variation observed in the ‘invasiveness’ of strains in cattle exposed to contact infection.

Attention is drawn to the significance of the observations recorded in this paper in relation to tests of foot-and-mouth disease vaccines for non-infectivity.
The titration of influenza virus-neutralizing antibodies
Authors: Fulton Forrest , Friend J. E.
Published: May 2009

A method of titrating influenza virus-neutralizing antibodies is described. This method is based on the technique for cultivating virus in fragments of chick chorio-allantoic membrane using a special plastic tray with cups for 100 replicates. The neutralization test cannot be made directly by adding the antiserum to the cups in which the virus is growing in the membrane fragments because there is a significant non-specific inhibitory effect. Therefore, use is made of the observation that virus added to the cups is rapidly fixed by the membrane so that, after a short time, the membrane may be washed and transferred to a fresh cup which will later be found to contain the new virus released from the membrane.

In the neutralization test the membrane fragments are exposed to virus-serum mixtures for 18 hr. and then transferred to other cups without serum to determine which pieces have become infected. The titre of neutralizing antibodies is defined as the serum dilution which will protect from infection with 100 ID 50 of virus, half of a large number of replicate pieces of membrane.

The neutralization technique has been applied to the antigenic comparison of six strains of influenza virus. The results support the relationships disclosed between the six strains by a complement-fixation technique. It is suggested, however, that the neutralization technique, because of its greater specificity, and because of its dependence on the infectivity of the strain, is not as satisfactory as the complement-fixation test for strain comparisons. Apart from its use for titrating neutralizing antibodies, the technique may also be of value for proving the virtual identity of two virus strains and in the selection of strains for a vaccine.

It is a pleasure to acknowledge the help given by Dr Isaacs of the WHO Influenza Centre. Not only did he provide many of the virus strains and antisera, but he also undertook the purification of the WS strain.
The anaerobic cocci: gas formation, fermentation reactions, sensitivity to antibiotics and sulphonamides. Classification
Authors: Hare Ronald , Wildy Peter , Billett F. S. , Twort D. N.
Published: May 2009

1. A total of ninety-nine strains of anaerobic cocci from human beings have been studied and six groups demarcated on the basis of gas formation and fermentation reactions.

2.Gas formation by strains of group I is due to fermentation of glucose, laevu-lose or maltose, with a sulphur compound as an activator and with the production of gas rich in CO2.

3.Gas formation by strains of groups II, III and V is due to fermentation of different organic acids, sulphur not being required, and accompanied by the production of gases containing a high proportion of H2.

4.Two groups, IV and VI, do not from gas, but the latter has marked fermentation abilities.

There is correlation between microscopic apperances, probable pathogenicity, sensitivity to antibiotics and sulphonamides and the groups demarcated.

Ninety-two out of ninety-nine strains isolated from human beings could be placed in one or other group.

We are greatly indebted to Dr H. J. Parish of the Wellcome Research Laboratories for a sample of Polymyxin E, to Prof. L. Young for much assistance and advice and to those colleagues, particularly Dr R. M. Caiman of Queen Charlotte's Hospital, who sent us strains.
Bacteriophage typing ofstaphylococcus aureus
Authors: Williams R. E. O. , Rippon Joan E.
Published: May 2009

The routine methods for propagation of staphylococcal typing bacteriophages, and for their use in identifying strains of staphylococci, are described.

Most of the phages can be propagated in fluid media as well as on agar, and for some glucose-peptone-water is a better medium than nutrient or Todd-Hewitt broth.

Many phage filtrates derived from broth or agar propagation contain, in addition to the phage, an agent that inhibits the growth of staphylococci.

Investigations of variations in the routine typing technique showed that considerable latitude is permissible in the age of cultures used for typing and in the inoculation procedures. It is, however, important to test all phage filtrates after propagation for purity and freedom from the inhibitory agent; and to repeat the tests frequently during use to detect alterations in titre.

About 40% of staphylococci are not lysed by the phages used at their test dilution; about half of these untypable strains are lysed by undiluted phage filtrates.

An analysis was made of the results of typing 567 independent strains of staphylococci; 229 of these showed strong lysis by one or more phages, but there were no fewer than 82 distinct phage patterns represented, and only 118 strains were lysed strongly by a single phage. Certain phages tend to appear together in patterns and on the basis of such associations three main phage groups can be distinguished; they are known respectively as the ‘3A’, ‘6/47’ and ‘52’ groups.

No method was discovered for segregating patterns into ‘types’, but conventions have been devised on the basis of the variation observed in sets of strains from various sources, for distinguishing between different patterns.

We are deeply indebted to Dr V. D. Allison for teaching us the bacteriophage typing methods and for giving us the benefit of his wide experience.

We are grateful to the following for sending us phages, and in some cases discussing their results with us: Dr Phyllis Rountree, Sydney; Dr R. Wahl, Paris; Dr G. Wallmark, Stockholm; Dr H. Williams Smith, Poultry Research Station, and Mr A. M. Hood, Birmingham.

Our thanks are also due to Miss S. Mayo, Mrs E. Lyons and Mr D. Woodroof for technical assistance. The photographs for PI. 14 were taken by Mr W. Clifford.
Bacterial contamination of hospital food with special reference toClostridium welchiifood poisoning
Authors: McKillop Elizabeth J.
Published: May 2009

1. An examination of eighty-nine samples of uncooked and thirty-eight samples of cooked food purchased by one particular hospital showed that the purchased food was bacteriologically clean.

2. A similar examination of 173 samples of food after it was cooked and prepared for serving in the hospital kitchens showed that, with the exception of cold chicken, the bacterial flora was greatly reduced by cooking. Ten of forty-six samples of cold chicken, however, were contaminated with fairly large numbers ofCl. welchii.

3. An investigation into the cooking and handling of the fowls indicated that contamination of the cooked fowls with kitchen dust was a probable explanation for the presence ofCl. welchii.

4. Immediate refrigeration of the fowls, well separated on shallow trays, was shown to be a satisfactory method of preventing the growth of contaminatingCl. welchiito any dangerous extent.

5. Six outbreaks of food poisoning, in which there was an association between cold chicken and the clinical symptoms ofCl. welchiifood poisoning, are reported and discussed.

I have pleasure in thanking Dr Betty Hobbs of the Food Hygiene Laboratory of the Public Health Laboratory Service at Colindale for the serological typing of numerous strains ofCl. welchii; Mr D. B. Colquhoun for assistance with the phage-typing of the staphylococci; Mr G. Kerr for the photography; and the kitchen staff in the hospital concerned for making possible the numerous samplings of food and the other inquiries into the day-to-day affairs of the hospital catering department.
The effect of some variables on experimentalKlebsiellainfections in mice
Authors: Epstein Samuel S. , Payne Peter M.
Published: May 2009

The virulence of nine strains ofKlebsiellawas tested in mice inoculated by peritoneal and oral routes, the latter being a convenient method of inducing pneumonic infections.

At similar doses, shorter survival was observed in young mice. Injected by the intraperitoneal route, organisms from 16 hr. old cultures proved more virulent than those from older cultures, but no such difference was obtained orally. Repeated subculture of a virulent strain failed to attenuate its oral virulence and killed suspensions of the same strain were without effect. With only two exceptions, all strains were more virulent when administered orally than intraperitoneally. Wherever possible the concept ofrelativevirulence was employed in making statistical comparisons. It is, however, considered that virulence is an unsatisfactory taxonomic discriminant.

We would like to thank Dr I. Friedmann, Dr F. Fulton and Dr G. Meynell for their helpful criticism. We are also indebted to Dr Lynne Reid for her comments and to Mr G. B. Newman for checking the calculations. Thanks are also due to Mr G. D. Breach and Mr G. Latchford for technical assistance, to Mr D. Connolly for preparation of graphs and Mrs A. Gorvin for secretarial assistance.
A re-assessment of the risk of provoking paralytic poliomyelitis by Making prophylactic inoculations against diphtheria and pertussis
Authors: Holt Lewis B.
Published: May 2009

The variables operating in respect of the risk of provoking paralytic poliomyelitis by inoculating children with different prophylactic reagents have been analysed.

It is concluded that the use of combined diphtheria fluid toxoid and pertussis vaccine, administered in early infancy, incurs a minimal risk and is to be recommended because of its immunological effciency, its unquestionable value in helping to maintain a high immunization rate against diphtheria in the child community and for its marked administrative convenience.
The influence of the thyroid gland on antitoxin production in different species
Authors: Shewell Jennifer , Long D. A.
Published: May 2009

1. The influence of the thyroid gland on the production of antitoxins to two alum-precipitated bacterial exotoxins has been investigated in different animal species.

2. Rats, rabbits and mice produce more circulating antitoxin when thyroidectomized, and less when made hyperthyroid by thyroxine administration, than control animals.

3. Guinea-pigs produce slightly less antitoxin when thyroidectomized, and markedly more when thyroxine treated, than control animals.

We are grateful to Dr J. S. F. Niven for histological examination of tissues, and to Miss M. V. Mussett, B.Sc., for statistical analyses. The alum-precipitated tetanus toxoid XW 2044, and tetanus toxin XW 1322, were kindly supplied by Miss Mollie Barr, M.Sc., of the Wellcome Research Laboratories, Beckenham, Kent, and we are also grateful to Mr P. Rodican of the Lister Institute, Elstree, for a supply of tetanus toxin 829.
The survival of Shigella sonnei on cotton threads
Authors: Spicer C. C.
Published: May 2009

1. Experiments have been carried out to estimate quantitatively the survival of Sh. sonnei at various R.H.'S and two different temperature ranges.

2. A fraction may survive for 7–10 days under favourable conditions.

3. At R.H.'S of 40–60% the organism survives less well than at higher or lower values.

4. Survival is better at temperatures of 5–10°C. than at 20–30°C.

I am very grateful to Mr T. Nash for his advice during the course of this work, and also to Col. H. J. Bensted for his comments on the MS.
The association of starch-accumulating strains of Group A streptococci with acute nephritis and acute rheumatic fever
Authors: Crowley Nuala
Published: May 2009

On the basis of starch synthesis and degradation by the strains three subdivisions of Group A streptococci were made. In defined cultural conditions about a third of the strains accumulated starch, the majority belonging to one subgroup. Of patients from whom starch-accumulating strains were isolated at the onset of infection, the observed numbers who developed either acute nephritis or acute rheumatic fever were more than three times the expected numbers. Of eighty-six strains, including forty-six members ofType 12, and forty belonging to several other serotypes, which were associated with either nephritis or rheumatic fever, more than 90% were starch-accumulating strains. Though 47% of allType 12strains accumulated starch, there was a primary association of starch-accumulating strains and the sequelae, irrespective of serotype. On the basis of type-frequency, and the starch synthesizing and degrading activities of the three most common serotypes,Types 1, 4and 12, together with the host factor (for only 25% of patients infected with starch-accumulating strains developed the sequelae) the chances ofType 12incidents are four to one againstTypes 1and 4. The probability of the findings occurring by chance was considerably less than 0·001.

Technical assistance was paid for by grants from the Royal Free Hospital Endowment Fund, and I thank the Board of Governors of the Hospital. The drawings were made by Mrs Audrey Besterman, medical artist. For all their help and patience I wish to thank Dr R. E. O. Williams, Dr M. Patricia Jevons, Mr W. R. Maxted, Dr P. J. L. Sequeira, Dr W. J. Whelan and Dr Rebecca Lancefield.
The isolation of salmonellae from the mesenteric lymph nodes and faeces of pigs, cattle, sheep, dogs and cats and from other organs of poultry
Authors: Smith H. Williams
Published: May 2009

1. The mesenteric lymph nodes and faeces of pigs, cattle, sheep, dogs and cats and the intestinal wall and other organs of chickens in Essex, England, have been examined for salmonellae. These animals were either healthy or were not suffering from clinical salmonella infection.

2. Salmonellae were isolated from the mesenteric lymph nodes of sixty (12%) of 500 pigs, nine (4·5%) of 200 dogs, five (2·5%) of 200 cats and none of 200 cattle and 100 sheep. None was found in the chickens.

3. One (0·5%) of the cats and one (0·5%) of the dogs and six (1·2%) of an additional 500 healthy pigs were excreting salmonellae in their faeces.

4. Of the seventeen serotypes found in pigs, Salm. typhi-murium, Salm. anatum and Salm. cholerae-suis occurred most frequently.

5. All strains of Salm. cholerae-suis were isolated in brilliant green MacConkey broth; selenite broth was unsuitable for this purpose.

6. Despite the high isolation rate from pigs, clinical salmonella infection was diagnosed relatively infrequently at this laboratory. Salm. cholerae-suis was isolated from only one of seventeen epidemiologically unrelated cases of necrotic enteritis in pigs.

7. The results are discussed from the public health and agricultural view points with particular regard to the part infected feedingstuffs may play in causing salmonella infection in animals.

The expenses of the investigation were, in part, defrayed by grants from the Agricultural Research Council, whose help I gratefully acknowledge.

I am grateful to Mr A. J. Harman and Miss Linda Kelly for their capable technical help and to Dr K. C. Sellers for useful suggestions made during the course of this work. I am also indebted to Dr Joan Taylor for typing all the salmonella cultures and to Mr L. G. Smart for collecting the lymph nodes from the cattle, sheep and pigs.
Ultracentrifugal and electrophoretic studies on neonatal calf sera and maternal colostrum
Authors: Johnson P. , Pierce A. E.
Published: May 2009

1. Neonatal serum proteins and those of maternal colostrum have been examined in the Spinco analytical ultracentrifuge and the Perkin-Elmer electrophoresis apparatus. To facilitate correlations between the two types of result, certain protein fractions have been prepared electrophoretically and examined in the ultracentrifuge.

2. The electrophoretically distinguishable components of precolostral serum, albumin, α and β globulin and traces of γ globulin sedimented mainly as a single boundary which showed evidence of a slower component (probably fetuin) with a sedimentation constant of about 3S. A small proportion of a macroglobulin component (S020 ≅ 16S), associated with the α globulin, was also present. In conformity with the very low γ globulin, there was a complete lack of globulin with S020 ≅ 6·5–7·0S. The β globulin and the bulk of the α globulin sedimented closely with albumin, whose sedimentation constant in an electrophoretically isolated fraction was somewhat lower than normal, probably as a result of α-globulin contamination.

3. The electrophoretic and ultracentrifuge analysis of postcolostral calf serum showed evidence of passive absorption from the maternal colostrum of immune lactoglobulin. There was a rise in the concentration of total serum protein of which up to 51·6% was immune lactoglobulin, of sedimentation constant 6–6·5S. No such component occurs in precolostral sera. The electrophoretic and ultracen-trifugal characteristics of this globulin were not significantly altered as the result of absorption. The acquisition of immune lactoglobulin was accompanied by a simultaneous fall in serum albumin concentration.

4. Examination of colostrum, rennin-produced colostral whey, and of electrophoretic fractions prepared from colostrum showed the presence of a small proportion of a macroglobulin (S020 ≅ 18S), a well-defined immune lactoglobulin of S020 ≅ 6·4S and electrophoretic properties in the γ-range, and a group of electrophoretically more mobile components with sedimentation constants ranging downwards from 3S.

5. Electrophoretically prepared fractions from the serum of a deprived calf 27 days old showed sedimentation properties in conformity with the results on precolostral sera, with the macroglobulin component being again associated with α globulin. The remainder of α and β globulin sedimented alongside albumin and the additional γ-globulin component in a single boundary of S020 ≅ 6·5–7S.

6. The concentration of autogenous γ globulin developed by calves which had been deprived of colostrum increased with time and was generally in fair agreement with that of the 6·5–7S component.

The authors wish to thank Sir Alan Drury, F.R.S., for his interest and encouragement during the course of this work, Mr N. Buttress, Mr D. Hardman and Miss J. Mallon for technical assistance and Mr J. Clark for assistance in the care and handling of the calves.
A new phage-typing scheme forSalmonella typhi-murium
Authors: Callow Bessie R.
Published: May 2009

1. A new phage-typing scheme forSalm. typhi-muriumis described which initially defines thirty-four types of the organism.

2. Types recognizable with the older scheme of Felix and Callow remain distinct with the new system. However, the latter method offers a finer subdivision of the organism than does the former.

3. Thirteen of the twenty-nine typing phages used in the new scheme were prepared by adaptation ofSalm. paratyphiB typing phage 3b, and nineteen are serologically indistinguishable from this phage.

4. The lysogenic properties of the new types are discussed. Twenty-three out of the thirty-three type strains yielded both thermolabile and thermostable phages and a further three yielded thermolabile phages only. No phages could be isolated from the remainder.

5. The distinctive host ranges of the phages carried by most types can be used for type identification.

I am indebted to Miss Alison M. Dykes for her valuable assistance with this work; to Mr F. J. Flynn for help in the preparation of phage stocks; and to Dr E. S. Anderson for many helpful discussions and advice in the preparation of this paper.
The distribution of the underground rat population of a south Yorkshire drift mine
Authors: Twigg G. I.
Published: May 2009

Test baiting has shown that rats underground are distributed in a series of discrete colonies, each one in close association with a group of men. Interplay between colonies is rare in large mines although evident in small ones. In the absence of stables the rats must depend almost entirely on miners’ food scraps.

These observations were made during work carried out under a research grant from Safety in Mines Research Establishment, Ministry of Power, and I am indebted to the Ministry for permission to publish the results. I should like also to express my gratitude to Dr E. T. B. Francis who supervised the work, Mr. C. S. W. Grice of the Ministry of Power and Miss B. B. Jones of the Ministry of Agriculture, Fisheries and Food for their help in various aspects of the work.
The incidence and significance of Phase 1 complement-fixing antibody in Q fever
Authors: Powell O. W. , Stallman N. D.
Published: May 2009

1. An attempt has been made to follow up a consecutive series of seventy-two patients for the presence of Phase 1 C.F. antibody approximately 2 years or more after the acute illness. Fifty-one of the series were tested.

2. Fifteen of the fifty-one patients had detectable amounts of antibody, generally in low titre.

3. The presence of Phase 1 antibody correlated well, in older age-groups, with the duration of convalescence following the acute illness. There was no correlation with the duration of fever.

4. All cases with Phase 1 antibody also had Phase 2 antibody, usually in slightly higher titre. In no case in which Phase 2 antibody was absent or present in low titre was Phase 1 antibody found.

5. It is suggested that the presence of Phase 1 C.F. antibody is an indication of past persistent infection. It cannot necessarily be concluded that it is an indication of present persisting infection.

We wish to thank Dr H. Silverstone, Senior Lecturer in Medical Statistics, University of Queensland, for statistical advice.
Effect of treatment in percolating filters on the numbers of bacteria in sewage in relation to the composition and size of filtering medium
Authors: Tomlinson T. G. , Loveless J. E. , Sear L. G.
Published: May 2009

For a period of a year the total count, Coli-aerogenes count and turbidity were determined on samples of sewage and effluent taken every week from pilot-scale percolating filters treating domestic sewage. The eight filters contained four types of filtering medium in two sizes.

Numbers of coliform bacteria in the settled sewage were much higher during the warmer months but the total count showed no regular seasonal variation. Treatment in all the filters reduced the numbers of bacteria in both groups by over 95%. In general the reductions in numbers of bacteria and in numbers of all particles in suspension were proportional to the total area of filtering medium with which the sewage came into contact. The probability of discharging more than 10,000 coli-aerogenes per ml. ranged from 10% in the most efficient to 90 % in the least efficient filter.

Experiments in which Serratia indica was added to the influent sewage showed that only 0·4 % were recovered in the settled effluent after 24 hr. Treatment in the filters had little selective action on the different types of coliform bacteria.

This paper is published by permission of the Department of Scientific and Industrial Research.