bluuebunny/crossref_metadata_2025_split huggingface dataset:
The variability in gel-Producting properties of commercial agar and its influence on bacterial growth
Authors: Fulthorpe A. J. 
Published: May 2009

1. The rigidity of agar gel in poured agar plates can be tested by a comparatively simple and easily repeatable method.2. Commercial agar from different sources varies in the rigidity of gel it produces at a given concentration.3. The rigidity of gel produced by any agar at a given concentration is affected by processing and by the mode of production of poured plates and to some extent by the diluent used.4. The appearance of a spurious S-R change in colonies of Salmonella and Shigella on media with an increasing agar content is a measure of the rigidity of the agar gel used and not directly of the agar concentration of the medium.5. The appearance of this spurious S-R change induced by rigid agar bears no relation to the agglutinability of the organism.6. Both increased or decreased agglutinability of cultures of Salmonella and Shigella is associated with the appearance of colonies of an apparently rough morphology at a lower level of agar rigidity than that at which spurious S-R change develops in a normally agglutinable culture.7. Without some standardization of the rigidity of the gel used in agar plates, erroneous conclusions may be drawn regarding the antigenic state of the organisms under test.8. Samples of agar of differing gel rigidity can be blended to form a product producing a gel of a calculated 12 sec. value.I am indebted to the Director-General, Army Medical Services, for permission to publish this article.
Inter-hospital cross-infection of epidemic infantile gastro-enteritis associated with type strains of Bacterium coli
Authors: Rogers K. B. , Koegler S. J. 
Published: May 2009

Evidence of how epidemics of infantile gastro-enteritis can spread from one hospital to at least three other hospitals has been presented. Three such outbreaks are described, in two of which the α-type of Bact. coli, and in one the β-type of Bact. coli, were associated with the cases of enteritis.It is suggested that in hospitals which admit infants routine examination of the infants' faeces should be made to identify these types of Bact. coli, and that institutional epidemics of gastro-enteritis should be notified to a central bureau together with the cultural findings, so that the pooled knowledge could be redistributed to paediatric centres.The aetiological relationship between infantile gastro-enteritis and these type strains of Bact. coli is briefly discussed.
The kinetics of the lysis ofBacterium coliby glycine
Authors: Gordon J. , Hall R. A. , Stickland L. H. 
Published: May 2009

The lysis ofBacterium colisuspensions brought about by glycine shows the following characteristics:(1) There is a latent period of 2 hr., followed by a rapid lysis reaching a maximum in about 8 hr.(2) The extent of the lysis is independent of the dilution of the bacterial suspension over a wide range.(3) The extent of the lysis increases with the glycine concentration up to 10M, but is approaching a limit at this concentration.(4) The lysis is negligible below pH 5 and above pH 10, and shows a maximum rate in the region of pH 6–5–8–5.(5) The rate of lysis has a very high temperature coefficient (Q10 of the order of 5).
Surviving tissue suspensions for influenza virus titration
Authors: Fulton Forrest , Armitage P. , Friend J. E. 
Published: May 2009

A new method of titrating the infectivity of egg-adapted influenza virus suspensions is described.For this purpose a plastic tray has been made, drilled with one hundred conical cups. In each cup a small piece of chorio-allantoic membrane from a chick embryo is suspended in a buffered salt solution. To these surviving tissue suspensions virus dilutions are added, and the tray is put in an incubator and rocked mechanically for 60 hr.In those cups in which the inoculum has been sufficiently large, the membrane becomes infected by the virus which multiplies within the cells and, bursting out, builds up by infection of other cells a high concentration of virus in the suspending fluid. The virus multiplication is detected by removing the pieces of tissue and adding to the cups a drop of washed chicken erythrocytes. The presence of virus in the cup is shown by the pattern of the sedimented erythrocytes, and virus multiplication is inferred because the original seed virus is too dilute to be detectable by haemagglutination.The method has been compared with in ovo titration. As a means of detecting egg-adapted infective virus, the tissue suspension is between 20 and 80 times less sensitive; as a titration system, however, approximately one cup is equivalent to one egg, so that by using sufficient replicates accurate assays of infective virus can be made.The technique is readily adaptable to the titration of serum-neutralizing antibodies.In addition to haemagglutination, the infectivity end-point of the titration can also be estimated by a specific complement fixation test, and it is suggested that, with modifications, the new technique may be applicable to the titration of a large number of other viruses.
The preparation, testing and standardization of typhoid vaccine
Authors: Felix A. 
Published: May 2009

1. The review of the laboratory evidence published since the introduction, ten years ago, of the alcohol-treated typhoid vaccine furnishes additional support for abandoning the old method of making typhoid vaccine. The alcohol-treated vaccine has advantages in regard to both the Vi-antibody response and the degree of systemic reactions produced.2. The technique of the preparation of alcohol-killed and alcohol-preserved typhoid-paratyphoid vaccine has remained as originally described. The methods of selecting the vaccine strains and routinely examining the cultures have also remained unchanged.3. The necessity of testing typhoid vaccines not only by active-immunity tests in mice but also for their antibody-stimulating properties is again stresssed. These tests consist of immunization of rabbits, estimation of their Vi- and O-agglutinin titres and passive-immunity tests in mice.4. The most important sources of error in mouse-protection tests are:(a) the use of a test culture of less than the maximum degree of mouse-virulence;(b) the use of the mucin technique;(c) immunization by intraperitoneal injections when the challenge dose also is given by this route.Much of the experimental work on typhoid vaccine has been invalidated by these three pitfalls.5. It is suggested that the mucin technique be abandoned in the assay of typhoid vaccine.6. A source of error in the rabbit test is the presence of pre-formed Vi agglutinins. These are found in rabbits harbouring coliform organisms which possess the typhoid Vi antigen. Such rabbits do not respond to injections of typhoid Viantigen.7. Standardization of the potency of typhoid vaccine has now become possible. Either an alcohol-preserved or a dried vaccine can serve as ‘standard vaccine’, to be used in combination with the ‘Provisional Standard Anti-typhoid Serum’. Both of these vaccines remain stable for a number of years.8. Suggestions are briefly outlined for:(a) the routine examination in the course of preparation of the vaccine;(b) the official control of the potency of typhoid vaccine.9.The paratyphoid components of T.A.B.C. vaccine can be standardized in an analogous manner.
A hospital outbreak of typhoid fever
Authors: Bradley W.H , Evans L. Wilson , Taylor Ian 
Published: May 2009

1. An epidemic of typhoid fever involving 135 persons in a semi-closed community of. 742 persons is described.2. There were nineteen symptomless excreters (14·1%).3. Among the 116 clinical cases there were seven deaths, giving a case fatality of 6.03%. If the case fatality were calculated on the total persons involved (including symptomless excreters), the figure would be 5·2%.4. The origin of the outbreak was not discovered, but there was strong cricumstantial evidence in favour of a milk-borne infection.
Studies on respiratory infection: II. The influence of aerosol particle size on infection of the guinea-pig with Pasteurella pestis
Authors: Druett H. A. , Robinson J. M. , Henderson D. W. , Packman L. , Peacock S. 
Published: May 2009

The LD50 dose of Past. pestis is much greater when tested by the respiratory route than by subcutaneous challenge. This is probably due to trauma inflicted on the airborne particles.Two forms of plague, both originating in the respiratory tract of the guinea-pig, can develop according to the size of the particle containing Past. pestis presented to the host. Small particles initiate a broncho-pneumonia which leads to septicaemia and death. Large particles establish a septicaemia, and death results more quickly without the development of a pneumonia.Cross-infection to normal animals occurs irregularly when they are exposed to others developing plague by the respiratory route. Such incident is rare when the initially infected animals are exposed to large particles. Cross-infected animals suffer from the disease characteristic of exposure to large particles. Attempts to establish an epizootic by cross-respiratory infection were abortive, probably due, in some measure, to the type of disease developing in first cross-infections.
The distribution of vaccinia virus, complement-fixing antigen and haemagglutinin throughout the egg after inoculation of the chorio-allantoic membrane
Authors: Tobin Barbara M. 
Published: May 2009

Vaccinia virus inoculated on the chorio-allantois and causing infection spread to the uninoculated part of the membrane, the embryo, the allantoic and amniotic fluids and the yolk within 1 day.The virus grew in the embryo and possibly in the uninoculated part of the chorio-allantois, but in the latter no macroscopic lesions were detected.Virus increased in amount in the allantoic fluid and may have grown in the lining of the allantoic sac; it did not increase in the amniotic fluid; it was present in yolk and increased slightly but its local growth was doubtful.The presence of haemagglutinin and complement-fixing antigen was related to the amount of virus.Allantoic fluid from infected eggs could be a ready source of antigen for complement-fixation.
Haemolytic disease of the newborn piglet
Authors: Goodwin R. F. W. , Heard D. H. , Hayward B. H. G. , Roberts G. Fulton 
Published: May 2009

Four litters of newborn piglets suffering from haemolytic disease of four different grades of severity, were observed clinically. Pallor and mild jaundice were evident in some cases, but the activity of the piglets was not reduced except in the terminal stages of fatal cases. Malnutrition affected a number of piglets sometimes from fortuitous factors. In mild cases there were no clinical symptoms, and the disease could be detected only by demonstrating a fall in haemoglobin level or sensitization of the red cells.Several blood group systems were concerned in the genesis of the disease in these piglets and both agglutinating and incomplete antibodies were shown to be present in the piglets' circulations; in one case antibody was found in the piglet's circulation only 3½ hr. after suckling started, and by 4 hr. the titre of free antibody was 256. The antibodies did not pass the placenta.In severe cases a rapid fall in haemoglobin, interrupted by a sharp, transient rise, and accompanied by reticulocytosis and erythroblastaemia, was characteristic of the first 24 hr.; this was followed in some cases by a prolonged low level of haemoglobin before recovery started.In some of the animals that died, severe and widespread focal necrosis of the liver, together with degeneration and necrosis in the kidney, were marked. Pigment deposits and erythrophagocytosis were common in nearly all organs but abnormal extramedullary erythropoiesis was not observed.A number of haematological, serological and biochemical findings are recorded.
The immunity to Salmonella gallinarum infection in chickens produced by live cultures of members of the Salmonella genus
Authors: Smith H. Williams 
Published: May 2009

1. The immunity to Salm. gallinarum infection produced by injecting chickens with live cultures of different species of Salmonella and other bacteria has been studied.2. Salm. pullorum produced a complete immunity equal to that produced by Salm. gallinarum itself. The immunity evoked by 11 of 12 other Salmonella species belonging to group D, although substantial, was less complete. Three of four rough group D strains and an avirulent strain of B. coli produced no immunity. Although a considerable degree of immunity was produced by the fourth rough strain it was not equal to that produced by rough strains of Salm. gallinarum.3. Owing to their lethal nature, it was not possible to be definite about the extent of the immunity produced by two group B strains, Salm. typhi-murium and Salm. Chester, although it may have been equal to that produced by the group D strains.4. A slight but definite degree of immunity was produced by two group C and two group E Salmonella cultures. Since this immunity was no better than that possessed by chickens previously infected with either Pasteurella septica or Staphylococcus aureus, it was considered to be non-specific in character.
The Varying Epidemiology of Q Fever in the South-East Region of Great Britain I. In an Urban Area
Authors: Marmion B. P. , Harvey M. S. 
Published: May 2009

An investigation in an urban area of south-east Kent of 160 patients who had had either pneumonia or unexplained fever during the period from the end of 1948 to the beginning of 1954 revealed that twenty-three (14%) had probably had Q fever.A comparison of the epidemiological histories of patients who had had Q fever with those of the remainder showed that the use of a household supply of raw milk was commoner among the former.Occupational exposure to animals (or animal products), visits to potentially infectious places, or residence near potential sources of infection were not significantly more frequent among the Q-fever cases as compared with the controls.The isolation ofRickettsia burnetifrom the bulked milk of some local herds supplying retail dairies in the towns, together with the general epidemiological evidence, suggested that Q fever in the towns was predominantly milk-borne.
The mechanism and prevention of cross-infection in dermatological wards
Authors: Selwyn S. 
Published: May 2009

Over a 2-year period a dermatology department was shown to be a valid model for the long-term study of hospital cross-infection. In the absence of specific anti-bacterial measures, consistently high levels of Staph. aureus and Gram-negative bacilli were found throughout the environment. ‘Broadcasts’ of Staph. aureus were particularly evident in the bathrooms, and notable sites of heavy, cumulative contamination were the communal baths, bedding, settled dust, and the hands of the staff.Cross-infection of lesions occurred in ninety-four of the 233 ‘uncontrolled’ patients—15 cases being due to Gram-negative bacilli. Autogenous infection occurred in another fifteen cases. Nasal carriage of Staph. aureus developed in fifty-one patients after admission.In one of the two main wards nasal disinfection (with ‘Soframycin’ nebulizers) was used for 4 months, and was effective in the treatment and prevention of nasal carriage; but it produced no change in the level of environmental contamination or in the incidence of cross-infection—even though efficient cleansing of the baths was also instituted. In contrast, during two separate periods of the work disinfection of skin lesions (with ‘Rikospray Antibiotic’) markedly reduced the counts of pathogens in the environment, and virtually abolished both cross-infection and the development of nasal carriage.
Studies on the pathogenesis of rinderpest in experimental cattle: IV. Proliferation of the virus following contact infection
Authors: Taylor W. P. , Plowright W. , Pillinger R. , Rampton C. S. , Staple R. F. 
Published: May 2009

Cattle were infected with rinderpest virus by housing them for 24 hr. in stalls containing donor animals which had been reacting to the disease for 3–5 days. They were then transferred to individual clean stalls and killed on the 2nd to 10th days following first exposure. Various tissues were collected, particularly those of the upper and lower respiratory tracts, and their virus content was estimated in calf-kidney tissue cultures.Virus was recovered from 15 of 35 animals tested and in eight of these generalization had occurred, although only two had begun to show a pyrexial response. The stage of the infection could not be predicted from the time that had elapsed following exposure, since early, limited proliferation was encountered on the 3rd to the 10th days.It was considered that seven animals gave indications of the pathways by which natural infection had occurred. In each of these virus proliferation was established very early in the pharyngeal lymph node; in three the submaxillary lymph node was similarly involved and in four the palatal tonsil. It was suggested that these data probably indicated that infection always occurred via the upper respiratory tract.In three cases virus titres were highest in the bronchial or costocervical lymph nodes; this was construed as evidence for the additional involvement of the lower respiratory tract in primary infection.No infectivity could be demonstrated in the mucosae or lung parenchyma associated with the above-mentioned lymph nodes and this, together with previously published data, was accepted as strong presumptive evidence that the infecting virus passes through the mucosae without producing a local lesion or proliferating there. These results were compared briefly with those of Bedson & Duckworth (1963) for rabbit pox.
Laboratory transmission of Enterobacteriaceae by the oriental cockroach,Blatta orientalis
Authors: Burgess N. R. H. , McDermott S. N. , Whiting J. 
Published: May 2009

SUMMARYMethods of maintaining and feeding and of infecting cockroaches with pathogenic organisms were investigated.Cockroaches fed on known concentrations ofEscherichia coli0119,Esch. coliO1, Alkalescens Dispar O group 2 andShigella dysenteriae1 (Shiga's Bacillus) were maintained in Petri dishes. The effect of various diets on the survival of these organisms within the hind-gut and faeces was observed. With a ‘normal’ diet of gruelEsch. coli0119 was isolated for up to 20 days,Esch. coliO1 for 17 days and ADO 2 for 15 days.Sh. dysenteriae1 was isolated only sporadically to the third day.
The use of the conglutinating complement fixation test in the diagnosis of human brucellosis
Authors: Farrell I. D. , Hinchliffe P. M. , Robertson L. 
Published: May 2009

SUMMARYThe conglutinating complement fixation test was compared with the haemolytic complement fixation test for the detection of brucella antibodies in human sera. Conglutinating-complement-fixation antibodies were detectable during the early stages of acute brucellosis and persisted for approximately 1 year after the infection.
Antibody responses in patients with farmer's lung disease to antigens fromThermoactinomyces vulgaris
Authors: Hollingdale M. R. 
Published: May 2009

SUMMARYA serological analysis of mycelial antigens ofThermoactinomyces vulgarisin immunodiffusion with human sera revealed five individual antigens. Three antigens were proteins, sensitive to pronase and soluble in phenol. Two were cationic polysaccharides, sensitive to sodium periodate, and containing glucosamine and muramic acid.Latex coated with mycelial antigens was compared with precipitin tests in detecting antibodies toT. vulgaris;the number of positive results detected by each test differed slightly, and a combination of the two tests detected the highest number. Counterimmunoelectrophoresis (CIE) was shown to be a very sensitive method for detecting precipitins, but not for their measurement. A prospective evaluation of immunodiffusion, latex agglutination and CIE as potential serodiagnostic techniques for farmer's lung disease is suggested.
Myxomatosis: passive immunity in the offspring of immune rabbits (Oryctolagus cuniculus) infested with fleas (Spilopsyllus cuniculiDale) and exposed to myxoma virus
Authors: Sobey W. R. , Conolly Dorothy 
Published: May 2009

SUMMARYKittens with maternal antibodies to myxoma virus, the offspring of rabbits which had recovered from myxomatosis, were exposed to fleas contaminated with myxoma virus and/or contact with infected rabbits from birth. All kittens died or became infected before 8 weeks of age. When compared with adult animals similarly infected the kittens showed no advantage in terms of survival time or recovery rate attributable to maternal antibodies. Flea transmission of virus was found more effective than contact transmissions.
The use of the haemagglutination-inhibition test for detecting antibodies to type SAT 2 foot-and-mouth disease viruses in cattle sera
Authors: Booth J. C. , Pay T. W. F. , Hedger R. S. , Barnett I. T. 
Published: May 2009

SUMMARYTwo strains of type SAT 2 foot-and-mouth disease virus which gave high titres of haemagglutinin activity reacted type-specifically in direct haemagglutinationinhibition tests with reference, bovine convalescent antisera. Comparisons of the haemagglutination-inhibition and the serum neutralization tests using cattle sera showed that both were equally specific and sensitive for detecting virus antibody.
Epidemiological studies of Epstein–Barr herpesvirus infection in Western Australia
Authors: Lai P. K. , Mackay-Scollay E. M. , Alpers M. P. 
Published: May 2009

SUMMARYIn a study on a Caucasian population in Western Australia the prevalence of antibodies to Epstein–Barr virus (EBV) was 41% in the 9- to 10-year age group, 80% in the 16 to 19-year age group and 92% in young adults. The age-specific annual seroconversion rates indicated two peaks of primary EBV infection in the population studied – one under 5 years of age and the other at adolescence. The geometric mean titre rose with age, from 23 at 5–6 years to 53 at 36–40 years.It was shown that in 73 families studied there was evidence of probable spread of EBV infection among siblings, particularly between those of the same sex.Serological study of patients with infectious mononucleosis indicated that 100% of those examined had antibody to EBV and the geometric mean titre was elevated to 210. Rising titres and seroconversion was demonstrated in these patients together with successful establishment of EBV-carrying cell lines from the peripheral blood in two-thirds of the cases.
Detection of endotoxins with the Limulus test in burned and unburned mice infected with different species of gramnegative bacteria
Authors: Jones R. J. , Roe E. A. , Dyster R. E. 
Published: May 2009

SUMMARYThe Limulus test detected endotoxins in the plasma of burned and unburned mice infected with different species of gram-negative bacteria. Individual strains of different species of gram-negative bacteria produced different amounts of endotoxin in the plasma of infected mice. Plasma from mice given lethal infections showed very high concentrations of endotoxin. Low concentrations of endotoxin in the plasma were tolerated by mice but high concentrations were invariably fatal. A polyvalent pseudomonas vaccine reduced endotoxin in the plasma of mice given lethal infections of Pseudomonas aeruginosa.
Citrobacter koseri. I. An extended antigenic scheme forCitrobacter koseri(syn.C. diversus, Levinea malonatica)
Authors: Gross R. J. , Rowe B. 
Published: May 2009

SUMMARYThe namesCitrobacter koseri,Levinea malonaticaandCitrobacter diversusare synonymous. As a result of the study of representative strains of these organisms an antigenic scheme comprising seven O antigens has been proposed. The examination of a further 165 strains from clinical sources suggests that an additional seven antigens should be included in the scheme. The serological and biochemical reactions of the test strains for all 14 O antigens are described.