bluuebunny/crossref_metadata_2025_split huggingface dataset:
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.
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 equationQ = 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.
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.