bluuebunny/crossref_metadata_2025_split huggingface dataset:
Plasmid pattern analysis of natural bacterial isolates and its epidemiological implication
Authors: Tietze E. , Tschäpe H. 
Published: May 2009

SUMMARYNatural isolates ofEscherichia coli, Salmonella typhimurium, Klebsiella pneumoniae, andProvidencia stuartiiwere analysed to determine their plasmid content. This data allowed the identification of nosocomial strains ofK. pneumoniaeandP. stuartiiand helped in the differentiation of epidemic strains ofE. coli0111 andS. typhimurium. Phenotypically similar isolates ofS. typhimuriumcould be shown to be of independent origin using plasmid pattern analysis. The dissemination of a particular plasmid through different strains ofS. typhimuriumresulted in a simulation of a very widely distributed epidemic strain, because the plasmid interfered with the phage type of its host strain in addition to determining re sistance properties. Plasmid pattern analysis disclosed two independently existing but interacting epidemic processes: a bacterial ‘epidemic’ strain may become disseminated over a large territory and may predominate there for a long time; a single plasmid, however, may also become distributed through many different bacterial strains and may spread over a large territory. Plasmid pattern analysis provides a valuable and universal epidemiological laboratory method.
The Haemolytic Organisms of Normal Infants' Faeces
Authors: Todd E. W. 
Published: May 2009

1. No entamoebae, cysts, or other parasites were found.2. Streptococci were present in the stools of all babies more than three weeks old, but only three haemolytic strains were isolated, which appears to be a lower proportion than occurs in adult stools.3. Colon bacilli were present in the stools of all babies more than two weeks old, and haemolytic strains occurred in 12 per cent, of the specimens examined, that is in the same proportion as in adult stools.4. Staphylococcus albus was much more commonly found than in adult stools and in greater abundance.5. There was no bacteriological difference between the stools of the 78 breast-fed babies and those of the 13 artificially-fed infants, except that the haemolytic strains of B. coli occurred relatively more frequently in the case of the artificially-fed infants but owing to the small number of haemolytic strains isolated it would be unwise to lay too much stress on these figures.In conclusion I wish to offer my sincere thanks to Dr Jewesbury, Physician to the Children's Department of St Thomas's Hospital, for supplying me with the necessary material and for information as to methods of feeding, and I am also greatly indebted to Professor Dudgeon and Dr Wordley for their constant help and advice.
The Diphtherial Infection in Scarlet Fever
Authors: Grant R. T. 
Published: May 2009

From consideration of the above evidence the following conclusions may be drawn:(1) The prevalence of diphtheria-like bacilli in the fauces of scarlet fever patients on admission to hospital does not definitely follow that of diphtheria outside either in seasonal or yearly prevalence.(2) The majority of such patients show no clinical evidence of the added infection. It is believed that they are instances of scarlet fever developing in diphtheria carriers, and the presence of the organism does not affect the prognosis. However, cases which present such clinical evidence as a mem branous angina are to be considered as instances’ of true double infection and in them the prognosis is bad.(3) Bacteriological examination of a series of cases belonging to the former group reveals the presence of true virulent diphtheria bacilli in about 36 per cent., and these organisms may persist in a virulent state for a considerable period.(4) Routine bacteriological examination to find these cases and their sub sequent isolation materially reduces the incidence of post-scarlatinal diphtheria.
Plague in Manchuria. I. Observations made during and after the Second Manchurian Plague Epidemic of 1920–21. II. The Rôle of the Tarabagan in the Epidemiology of Plague
Authors: Teh Wu Lien , Han Chun Wing , Pollitzer Robert 
Published: May 2009

(1) The existence of sporadic cases of natural plague among tarabagans has again been established.(2) The tarabagan is easily susceptible to pneumonic plague produced by the inhalation of B. pestis in spray form, and may contract, besides the acute infection, chronic type of the lung affection.(3) Our inhalation experiments have proved contacts to be liable to pulmonary plague infection in both acute and chronic forms. The existence of carriers among tarabagans seems also probable.(4) Tarabagans can be infected with plague by feeding upon artificially infected food, contracting an alimentary type of the disease. The B. pestis is easily cultivated from the intestinal tract of animals suffering from plague.(5) Our evidence shows that subacute or chronic plague may exist among tarabagans in Mongolia and Siberia, and thus form a connecting link in the epidemiology of plague in those regions.
Preliminary Note on Inhibition of Bacterial Growth by Amino-acids
Authors: Wyon G. A. , McLeod J. W. 
Published: May 2009

While amino-acids in appropriate concentrations have long been known as valuable aids to bacterial growth, it does not appear to have been recognised that in relatively low concentrations they are often inhibitory.Inhibition has been shown to occur with 10 out of 11 single amino-acids tested and with certain mixtures rich in amino-acids. The inhibitory concetration varies from 11 to 130 millimols per litre, or from 0·2 to 2%(wt./vol. ). It is of some intrest that the amino-acids inhibitory in the lowest concentration were the cyclic compounds—histidine, tyrosine, tryphane, phenylalamine. Of the chain compounds tested cystine was the most inhibitory.Several organisus belonging to various groups of bacteria are susceptible of inhibition by amino-acids; certain intestinal organisms are not susceptible. The effect cannot be attributed to the physical effects of high concentration.There is an apparent divergence between our results and those of workers who have recommended tryptic digests for stimulating the growth of some of the bacteria here shown to be readily inhibited by amino-acids. A suggested explanation of this divergence is that it is the products of partial protein digestion, the polypetides, which are mainly responsible for the effect of stimulating growth, not the amino-acids. A “polypeptide medium” might prove particularly valuable for bacterial growth.A metabolism experiment with glycine in high but sub-inhibitory concentration showed that the amino-acid is broken down by Staphylococcus aureus, at this concentration.
On the Differentiation of the Staphylococci, with Special reference to the Precipitin Reactions
Authors: Dudgeon Leonard S. , Simpson J. W. Hope 
Published: May 2009

(1) FiftyS. aureusand 30 S.albusstrains obtained from infective processes in man have been investigated. Such cultural reactions as were completed did not differentiate between strains of S. albus and S. aureus, or serve to group these cocci; we found, however, that 94 per cent, of the S. aureus strains fermented mannite, as opposed to 40 per cent, of the S. albus strains. These results are in accordance with the findings of Cummins and Cumming (1913) and Hine (1922).(2) A close degree of correlation between pathogenicity for rabbits, pigment formation, and biochemical activity was noticed among theS. aureusstrains. Out of 19 pathogenic strains ofS. aureus, 9 showed medium pigmentation and 10 were strongly pigmented.(3) Anti-sera were prepared by inoculating rabbits with living cultures, 24 hours old, of the various strains. TheS. aureusrabbits and a few of theS. albusreceived two preliminary doses of the specific vaccine, but little or no protective action was afforded from the doses of living cocci injected.(4) Nineteen out of 25 cultures ofS. aureuskilled rabbits, but only 3 out of 18 cultures ofS. albus.(5) Fifteen strains ofS. aureusand 15 ofS. albuswere used for the preparation of anti-sera, and tested against as many antigens as possible, by the methods described by Dudgeon and Bamforth.(6) Cultures ofS. aureusproduced efficient anti-sera more readily thanS. albuscultures, but when an activeS. albusanti-serum was produced, it appeared to be as effective as theS. aureusanti-sera.(7) A marked difference in efficiency betweenS. aureusandS. albusantigens was noted.S. aureusantigens were almost three times more active thanS. albusantigens.(8) Pathogenic strains ofS. aureusandS. albusproduced more efficient precipitin antigens than non-pathogenic.(9) From the microscopical examination of the deposit formed in the precipitin reactions, a difference was noted betweenS. aureusandS. albusantigens.(10) The study of the precipitin reactions has failed to show any hard and fast dividing line between staphylococci of different colours, or of different cultural reactions. We are inclined to agree with Winslow, Rothberg and Parsons (1920) and with Dudgeon's original view in 1908, that the pyogenic, Gram-positive staphylococci must be regarded as members of one common family.
“Bacillus anthracoides.” A Study of its Biological Characters and Relationships and its Pathogenic Properties under Experimental Conditions
Authors: Grierson A. M. M. 
Published: May 2009

1. There occurs in nature an organism belonging to the group of Gram-positive aerobic sporing bacilli which closely resembles B.anthracis, especially in its cultural characters.2. These organisms occur commonly in materials that are frequently examined for the presence ofB. anthracis.3. TheB. anthracoidesis pathogenic to guinea-pigs and mice under experimental conditions, and would appear to occupy a position between the virulentB. anthracisand the non-pathogenic members of the group of aerobic sporing bacilli, e.g.B. subtilis, B. mesentericus.4. Subcutaneous injection of cultures ofB. anthracoidesproduces a local inflammation with gelatinous oedema and a fatal septicaemia.5. Only large doses of living organisms are lethal and attempts to increase the virulence of this organism by various methods have not proved successful.6. Individual animals vary considerably in their resistance to the organism.7. With the exception ofB. anthracis, theB. anthracoidescontrasts with the other members of the group in its pathogenic properties under experimental conditions. Twenty-five strains of this organism have been isolated, each of which possesses pathogenic properties. The pathogenicity of 49 strains of other representatives of the group has been tested, and only one of these was found to have lethal effects.
Infra-red Radiation and Nasal Obstruction
Authors: van Dishoeck H. A. E. 
Published: May 2009

For the investigation of the Hill phenomenon, viz. the antagonism of short-and long-wave infra-red radiation in their influence on nasal obstruction, the commonly used rhinomanometric technique is not well suited. In this paper a new procedure is described, in which an air current is blown through the nose. In this way the nasal passability may be estimated, independent of respiratory movements. It proved to be desirable to make a selection of suitable experimental subjects with the aid of adrenaline and histamine tests; only those persons in which the opening by adrenaline and the narrowing by histamine sprays were clearly demonstrable were chosen.Long-wave infra-red rays constantly caused nasal obstruction.The shorter waves were much weaker in their shutting effect, and also decreased the narrowing of the nose when they were given in combination with the long-wave rays of an electric fire.A nasal passage closed by long-wave infra-red radiation may be partly opened by the short-wave rays; the possibility of surface cooling being the opening factor was excluded.Artificial cooling of the skin has a very marked opening influence.It is suggested that nose-opening and nose-shutting are correlated with cooling and heating of the Malpighian layer. Long infra-red rays will be completely absorbed in the layer and cause capillary stasis with local overheating. The shorter waves for the greater part penetrate more deeply; the skin reacts by an active hyperaemia, which, by relatively cooling the overheated Malpighian layer, has the same effect as a cooling from without.
Carriers and Return Cases in Scarlet Fever
Authors: Brown W. A. , Allison V. D. 
Published: May 2009

1. In view of the high carrier rate on discharge from hospital, the bacteriological examination of swabs from scarlet fever patients is of no value in the detection of probable infecting cases.2. There is, however, a definite relationship between the degree of infection, as measured by the profusion of haemolytic streptococci in cultures on discharge, and the likelihood of the patient infecting others.3. The causal connection between “infecting” case and return case is strongly supported by finding the same serological type ofStreptococcus pyogenesin both cases.4. A patient who has had complications in hospital is slightly more liable to become an infecting case than one whose course has been uncomplicated.5. The commonest age group of infecting cases is 5–10 years.6. The majority (70 per cent.) of the return cases occurred within 14 days of the arrival home of the infecting case.7. Overcrowding in the home, and the number of the susceptibles exposed do not appear to be important factors in the production of return cases.8. A history of tonsillectomy does not appear to bear any important relationship to the occurrence of infecting cases, but the inconclusive nature of our findings indicates the desirability of further investigation of this question and that of the relation of the condition of the tonsils to their infectivity.9. Discharge from hospital as early as is consistent with a satisfactory clinical condition is shown to be advantageous from the point of view both of the patient and of the hospital administration.10. The administration of scarlatinal antitoxin is likely to render a patient less liable to convey infection on discharge.
Skin Temperature in Relation to the Warmth of the Environment
Authors: Bedford T. 
Published: May 2009

The skin temperatures of industrial workers, mainly women and girls, engaged in very light occupations, have been correlated with environmental conditions. The temperatures of the forehead and of the palm of the hand were measured with a Moll radiation thermopile, and for the temperature of the foot a thermo-junction was used. Altogether 3085 sets of observations were made.Various measures of environmental warmth (dry-bulb air temperature, equivalent temperature, effective temperature, and dry kata cooling power) were correlated with skin temperature. The dry-bulb air temperature is about as good an index of skin temperature as any of the other measures used, while it appears that skin temperature may be slightly less closely associated with dry kata cooling power than with the other measures of warmth conditions.At an average air temperature of 18° C., the average skin temperatures observed were: on the forehead 34·25° C.; on the palm of the hand 29·2° C.; and on the foot 24·4° C. The average increases in skin temperature for a rise of 1° in air temperature were: on the forehead 0·139°; on the hand 0·465°; and on the foot 0·806° C.There was much variation in the skin temperatures recorded at any particular air temperature. The root-mean-square errors of estimation of skin temperature from air temperature were 0·81, 2·51, and 2·80° C., for the forehead, hands and feet respectively.Correlations between the temperatures of different areas of skin were rather lower than those between air and skin temperature.
The Occurrence of Typhoid Bacilli Containing Vi Antigen in Cases of Typhoid Fever and of Vi Antibody in their Sera
Authors: Felix A. , Krikorian K. S. , Reitler R. 
Published: May 2009

The investigation recorded in the present paper was undertaken as a corollary to the clinical trials with a new antityphoid serum, the results of which were recently published (Felix, 1935). Its object was to enquire into:(i) the occurrence of Vi antigen in strains of B. typhosus freshly isolated from cases of typhoid fever;(ii) the occurrence of Vi antibody in the blood serum of typhoid patients and convalescents.
On the Cultivation of the Nitroso-Bacterium
Authors: Fremlin H. S. 
Published: May 2009

In the first place cultures of the nitroso-bacterium were developed in inorganic solutions. These carried to a 5th dilution exhibited practically a pure culture of this species.Secondly, cultures of the nitroso-bacterium were inoculated into solutions containing small quantities of organic matter. In these they were able to oxidise the ammonia present. It was found that a culture developing in the presence of small quantities of organic matter was better able to oxidise the ammonia in higher percentages of organic matter than a culture taken directly from an inorganic solution.In growing this species on plates silica jelly has the disadvantage of being difficult to prepare. It was 18 months before I obtained a satisfactory plate. This jelly grows the nitroso-bacterium well, but other species can also develop colonies on it. Ammonia agar also grows the species, as shown by the oxidation of the ammonia, and the colonies assume a characteristic form.As to beef broth agar and gelatine, these media grew colonies of a micro-organism similiar to the nitroso-bacterium from oxidised ammonia cultures. Pieces of these plates containing such colonies in pure culture frequently oxidised ammonia in solutions. On the other hand pieces of such plates showing no colonies never produced any oxidations of the ammonia. Furthermore the single colonies from silica and ammonia agar plates, which oxidised the ammonia in the media into which they were sub-cultured, grew well on beef broth agar and gelatine.From the above results I have come to the following conclusions:(1) That the nitroso-bacterium grows well on any ordinary medium.(2) That the supposed parallel organism is no other than the nitroso-bacterium itself.(3) That in the presence of large percentages of organic matter the nitroso-bacterium, although growing very profusely, loses for a time the power of converting ammonia into a nitrite.
Experimental Studies Relating to Ship-beri-beri and Scurvy. II. On the Etiology of Scurvy
Authors: Holst Axel , Frölich Theodor 
Published: May 2009

(1) On the macroscopical alterations in the tissues of guinea-pigs which had been fed exclusively on bread, groats, and unpeeled grain.By experimenting with the “one-sided” diets which were used in the experiments, mentioned in the foregoing paper on polyneuritis in poultry, we found that guinea-pigs also contract a disease, and that this disease is accompanied by very characteristic changes.
The Contamination of Ice-cream
Authors: Buchan George F. 
Published: May 2009

(1) The premises of 50 manufacturers of ice-cream were inspected, their methods investigated, and bacteriological examinations made of samples taken“a” immediately after heating,“b” after cooling,“c” after freezing.(2) The trade is not carried on under the conditions or with the precautions necessary to secure a clean product.The sources of the contamination of ice-cream.(3) Bacteriologically polluted ice-cream is due to(A) Insufficient initial heating;(B) Contamination during cooling and freezing from(a) unclean vessels and covers,(b) the addition of unclean ice to hasten freezing,(c) the unclean hands of the manufacturer,(d) dirty surroundings.The scientific method of the manufacture of ice-cream.(4) To secure a pure ice-cream:(a) All vessels should be thoroughly cleansed immediately before use and reserved for the manufacture of ice-cream. They should be stored in a clean place.(b) The manufacturer's hands and forearms should be thoroughly scrubbed and cleansed before each stage of the process. The clothing likely to come in contact with the ice-cream should also be clean.(c) Fresh milk should be used in its manufacture.(d) The ingredients should be boiled directly over a fire for ten minutes, or heated by means of a water-bath at boiling point for 30 minutes. The latter method is the better as the former is liable to burn the mixture.(e) The mixture should be frozen, immediately after boiling preferably in a freezer of the American pattern. Thereafter the ice-cream should be kept frozen while in the vendor's possession.(f) No ice-cream should be exposed for sale 48 hours after boiling.(g) The premises on which ice-cream is manufactured should be approved and registered by the local authority and should be constantly supervised.
A New Method of obtaining Cultures from Single Bacterial Cells
Authors: Topley W. W. C. , Barnard J. E. , Wilson G. S. 
Published: May 2009

While investigating variations in agglutinability, occurring among certain strains of paratyphoid bacilli, it became desirable to obtain cultures derived from single bacterial cells. The technique at first adopted was that devised by Mutch (1919), but the results obtained were not satisfactory. Certain modifications of this method were attempted, but were no more successful.The main difficulty, and one which appears to us to have been far too little emphasised in all the methods hitherto described, has been encountered in obtaining satisfactory conditions for the microscopical observation of the bacillary suspensions employed. The difficulty of accurately observing hanging-drop preparations, and still more of controlling manipulation of them by microscopical observation, would seem to us to have been insufficiently realised; and the ease with which faulty interpretation of microscopical appearances may introduce fatal errors into work of this kind has not, perhaps, been fully taken into account.
Certified Milk in Relation to the Bacteriological Standard
Authors: Mattick A. T. R. , Williams R. Stenhouse 
Published: May 2009

This paper contains an analysis of the results of the bacteriological examinations of 184 samples of milk produced by Mr W. G. Symes, Manor Farm, Fordington, Dorset, between April 1st, 1921 and June 6th, 1924.The farmer holds a licence to produce Certified Milk which is despatched from the farm in sealed glass bottles. The samples were taken at random from the milk as it was bottled and were at once despatched by post to the laboratory, without placing in cold store. The age of the samples varied from 20–24 hours at the time of examination.
Filtration Experiments with Spirochaeta Schaudinnii
Authors: Smith E. C. 
Published: May 2009

SUMMARYIt has been shown that S. schaudinnii will easily pass through Berkefeld V filters under a negative pressure of considerably less than one atmosphere, but B. pyocyaneus was always found in the filtrates in association with the spiro-chaetes. Attempts to pass S. schaudinnii through Berkefeld N filters were uniformly negative.Inoculation experiments on native volunteers made with (a) filtrates containing S. schaudinnii and B. pyocyaneus, (b) a mixture of these organisms combined with B.fusiformis, and (c) an emulsion of B.fusiformis in broth, did not give rise to ulceration.