bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bacteriophage restriction in Salmonella typhimurium by R factors and transfer factors
Authors: Anderson E. S. , Threlfall E. J. , Carr Jacqueline M. , Savoy L. G. 
Published: May 2009

SUMMARYA total of 2716 R factors and transfer factors isolated from Escherichia coli and salmonellas of human and animal origin were studied for their phage-restrictive effects in Salmonella typhimurium phage type 36. All of 1402 wild fi+ factors were non-restricting. The F factor of E. coli K12 was unique among the F-like factors tested in that it inhibited lysis of type 36 by one typing phage. In contrast, eleven distinct changes in the phage type of 36 were produced by fi− I-like factors. I-like plasmids can thus be subdivided by this method.I-like R factors and transfer factors from human and animal enterobacteria were categorized by their phage-restrictive effects in type 36. Factors resembling Δ in this respect predominated among fi− I-like factor from human E. coli and S. typhimurium and from porcine E. coli. Δ-like and Coll-like fi− factors were equally distributed in bovine S. typhimurium. Coll-like factors were commonest in bovine and avian E. coli.
The immune response to infection with vaccinia virus in mice: II. Appearance of hypersensitivity, production of macrophage migration inhibitory factor and transformation of spleen cells in response to virus antigens
Authors: Hutt Lindsey M. 
Published: May 2009

SUMMARYThe appearance of specific hypersensitivity to virus antigens was examined in mice infected intravenously with vaccinia virus. Both immediate hypersensitivity, transferable by serum, and delayed-type hypersensitivity, transferable only by cells, were apparent 8 days after infection and demonstrable for at least a further 130 days. Production of macrophage migration inhibitory factor by lymphocytes from infected mice was measured directly in terms of inhibition of migration by antigen or indirectly by determining the effect of soluble factors elaborated by the stimulated lymphocytes. The irregular results may have been the resultants of antigen-mediated macrophage stimulation, toxicity and induction of migration inhibitory factor. Transformation of spleen cells – presumably lymphocytes – from infected mice could be inducedin vitroby virus antigens for at least 139 days after infection. Virus/lymphocyte interaction appears to be a particularly fruitful area for further study.
Mycoplasmas isolated from the respiratory tract of horses
Authors: Allam N. M. , Lemcke R. M. 
Published: May 2009

SUMMARYTen mycoplasmas were isolated from 130 nasopharyngeal swabs from thoroughbred horses with acute respiratory disease and three from 198 apparently normal horses. Two mycoplasmas were isolated from 21 tracheal swabs taken at necropsy. These mycoplasmas, together with six isolated from the equine respiratory tract by other workers, were subjected to biochemical and serological tests. Other properties examined in certain representative strains were appearance under the electron microscope, ability to adsorb or agglutinate the erythrocytes of various animal species and the electrophoretic pattern of the cell proteins.On the basis of these tests, mycoplasmas from the equine respiratory tract were divided into seven species. Three species belonged to the genusAcholeplasma, members of which do not require sterol for growth, and were identified asA. laidlawii, A. oculi(formerlyA. oculusi) originally isolated from the eyes of goats, and a recently named speciesA. equifoetale, previously isolated from aborted equine fetuses.Of the four sterol-dependentMycoplasmaspecies, one was identified asM. pulmonis, a common rodent pathogen. Another cross-reacted serologically withM. felisand should probably be classified as that species. The other two species probably represent new species peculiar to the horse. One of these, represented by the strains N3 and N11, ferments glucose and is serologically distinct from 19 recognized species of glucose-utilizing mycoplasmas and from two species which do not metabolize either glucose or arginine. The other species, represented by four strains, hydrolyses arginine and, because it is serologically distinct from all the named arginine-hydrolysingMycoplasmaspecies, the nameM. equirhinissp.nov. is proposed for it.Of the seven species, onlyM. pulmonisand the glucose-utilizing species represented by N3 and N11 were found exclusively in horses with acute respiratory disease.A. oculiwas isolated from an apparently normal horse. The other four species were found in normal horses as well as those with respiratory disease, although three out of the four strains ofM. equirhiniswere from sick horses.
Hypersensitivity in cattle after foot -and -mouth disease vaccination: response to hydroxypropylmethylcellulose
Authors: Black L. , Menard F. J. R. R. , Beadle G. G. , Pay T. W. F. 
Published: May 2009

SUMMARYIntravenous provocation (IVP) tests demonstrated that hydroxypropylmethylcellulose (MC) was able to elicit anaphylactic signs in cattle vaccinated with foot-and-mouth disease (FMD) vaccine produced at one centre but not with similar vaccine produced at another. The former vaccine also provoked serum reagins which were demonstrated by passive cutaneous anaphylaxis (PCA) tests in goats.Reaginic sera which reacted specifically with MC were used in PCA tests to screen samples taken serially from the vaccine production lines. The reactions observed suggested that a substance with MC or similar specificity was present in the antifoaming agent routinely added to vaccines.
The serological relationship betweenBrucellaspp.,Yersinia enterocoliticaserotype IX andSalmonellaserotypes of Kauffmann-White group N
Authors: Corbel M. J. 
Published: May 2009

SUMMARYThe serological relationship betweenBrucellaspp.,Yersinia enterocoliticaIX, and the group N salmonella serotypesS. godesberg, S. landau, S. morehead, S. neusdorf, S. soerengaandS. urbanawas examined using agglutination, antiglobulin, complement fixation, immunodiffusion and fluorescent antibody methods.Antisera to the group N salmonella serotypes all reacted to significant titres in agglutination and complement fixation, but not antiglobulin or immunodiffusion tests with smooth brucella antigens. These antisera also reacted in agglutination, but not antiglobulin, tests withY. enterocoliticaIX. They did not react significantly in any tests with rough brucella antigens.Conversely, antisera to smoothBrucellaspp. agglutinated group N salmonellas to low titre andY. enterocoliticaIX to titres similar to those given against the homologous strain. Antiserum toY. enterocoliticaIX on the other hand reacted with smooth brucella antigens to high titre in agglutination, complement fixation and antiglobulin tests, and with the group N salmonella antigens to substantial titres in agglutination tests.In direct fluorescent antibody tests, smoothBrucellastrains andY. enterocoliticaIX reacted strongly with FITC-labelled antibody toBr. abortuswhereas the group N salmonella strains reacted weakly.In tests with monospecific antisera to the A and M determinants ofBr. abortusandBr. melitensisrespectively,Y. enterocoliticaIX reacted only with the antiserum to the A determinant whereas group N salmonellas reacted to low titre with both A and M antisera.The results of cross-absorption tests confirmed this relationship and suggested that the O30 antigens of group N salmonella serotypes contained antigenic determinants similar to, but not identical with, the antigenic structure shared by smoothBrucellaspp. andY. enterocoliticaIX.
The isolation of salmonellas from British pork sausages and sausage meat
Authors: Roberts Diane , Boag Karen , Hall Mary L. M. , Shipp Christine R. 
Published: May 2009

SUMMARYBetween 1969 and 1974, 1467 packets (3309 samples) of pork sausages and sausage meat produced by two large and two medium sized manufacturers and several local butchers were examined for the presence of salmonellas. Of these, 435 packets (786 samples) were found to contain salmonellas, but there was a wide variation in the isolation rates according to the producer. The salmonella incidence in samples from several small and two medium sized producers was low (0–11%) while the results from the two large producers investigated showed a striking difference, the rate of salmonella contamination in the product of one was low (about 2%) and in that of the other consistently high (40–60%).A comparison of liquid enrichment media, incubation temperatures and selective agar media was also carried out to determine the most efficient combination for the isolation of salmonellas from minced meat products. The results showed that (a) incubation of enrichment cultures at 43° C. yielded a consistently greater number of salmonella isolations than at 37° C., regardless of plating medium, (b) tetrathionate broth A (Rolfe) was superior to selenite broth as an enrichment medium at both 37 and 43° C. and (c) brilliant green agar gave better results than deoxycholate citrate sucrose agar and bismuth sulphite agar as a selective medium.
The differential transmissibility of myxoma virus strains of differing virulence grades by the rabbit flea Spilopsyllus cuniculi (Dale)
Authors: Mead-Briggs A. R. , Vaughan J. A. 
Published: May 2009

SUMMARYLaboratory studies showed that few rabbit fleas (Spilopsyllus cuniculi (Dale)) transmitted myxomatosis after removal from wild rabbits (Oryctolagus cuniculus (L)) that had been infected for fewer than 10–12 days, irrespective of the virulence of the myxoma virus strain involved. Rabbits infected with fully virulent (Grade I) strains died within 10–15 days and few fleas from these hosts became infective; averaging all the samples taken, 12% of the fleas were infective. Also, few fleas acquired infectivity on individual rabbits which recovered from infection with attenuated strains; the mean was 8% infective. Rabbits which died between 17 and 44 days after infection had higher proportions of infective fleas at all sampling times; the mean was 42% infective. Male and female fleas transmitted virus with equal efficiency.For rabbits infected with any of the attenuated virus strains the mean percentage of infective fleas was inversely related to the survival time of the host. Rabbits infected with moderately attenuated strains (Grades IIIA and IIIB) had, on average, the highest proportion of infective fleas; hence such strains have a selective advantage and have become predominant under natural conditions in Britain. The changes that might occur if there is an increase in host resistance to myxomatosis are discussed.
Comparison of two methods for assessing the removal of total organisms and pathogens from the skin
Authors: Ayliffe G. A. J. , Babb J. R. , Bridges Kim , Lilly H. A. , Lowbury E. J. L. , Varney Janet , Wilkins M. D. 
Published: May 2009

A standard hand-wash sampling technique was compared with a simple fingerstreak sampling method in assessing the relative effectiveness of a number of alternative preparations used for disinfecting the surgeon's hands (alcoholic 0-5% chlorhexidine, alcoholic 0-1% tetrabrom-o-methyl phenol, a 4% chlorhexidine detergent solution, aqueous 0-5% chlorhexidine, 2% 'Irgasan' detergent solution and, as control, bar soap). There was a fairly good correlation between the results of assessment by the two methods after a single disinfection and after six disinfections, three on one day and three on the next. Significant differences were shown in 21 comparisons between treatments when the hand-wash sampling test was used, and 16 of these comparisons also showed a significant difference by the finger-streak test.Staphylococcus aureuswas found in hand samplings from 5 out of 8 nurses in the Burns Unit of Birmingham Accident Hospital by the hand-wash sampling method and from 2 of the same 8 nurses by the finger-streak method; the numbers were small, and noStaph. aureuswere isolated from the same hands after 1 min. wash in 70 % ethyl alcohol. Similar sampling on 29 nurses in other wards showedStaph. aureuson 3 nurses (one in large numbers) by the hand-wash technique and on 1 nurse by the finger-streak test; in only 1 nurse whose hands showedStaph. aureusbefore disinfection was the organism found, by hand-wash sampling, after disinfection.Parallel sampling of nurses' hands after washing with soap and water and after disinfection with 95 % ethanol showed larger numbers ofStaph. aureusin a hospital for skin diseases than in a general hospital, and a lower incidence and somewhat lower density ofStaph. aureusafter ethanol treatment than after washing with soap and water; Gram-negative bacilli, on the other hand, were commoner on hands in the general than in the skin hospital, and present in much smaller numbers after disinfection with ethanol than after washing with soap and water.Antibiotic sensitivity tests showed the frequent recurrence on the hands of some nurses of multi-resistantStaph. aureuswith resistance patterns similar to those found in infective lesions in some of the patients; different sensitivity patterns were usually found in staphylococci isolated from the nose. Even in wards where many patients were infected, carriage by nurses' hands of a particular strainofStaph. aureusdid not seem to last for more than a few days.
The effect of antibiotic therapy on the faecal excretion of Salmonella typhimurium by experimentally infected chickens
Authors: Smith H. Williams , Tucker J. F. 
Published: May 2009

SUMMARYChickens in groups of 40 were infected orally with a nalidixic acid-resistant mutant of Salmonella typhimurium and then fed continuously on diets containing ampicillin, chloramphenicol, furazolidone, neomycin, oxytetracycline, polymixin, spectinomycin, streptomycin or a mixture of trimethoprim and sulphadiazine. The amount of S. typhimurium excreted in their faeces was estimated at intervals by culture on brilliant green agar containing sodium nalidixate, both direct and after enrichment in selenite broth; the amount of Escherichia coli excreted was estimated by culture on MacConkey agar. The feeding of diets containing 500 mg./kg. of ampicillin, furazolidone, neomycin, polymixin, spectinomycin or streptomycin or 100 mg./kg. of trimethoprim and 500 mg./kg. of sulphadiazine for 46 days reduced to a varying degree the amount of S. typhimurium and E. coli excreted, the greatest reduction in S. typhimurium being brought about by the last treatment. The effect was less obvious when the concentration of the antibiotics in the food was decreased fivefold. An important reason for the very limited effect of some of the antibiotics was the emergence of antibiotic-resistant populations of S. typhimurium and E. coli. High concentrations of antibiotic-resistant organisms also arose in the faeces of the chickens fed diets containing tetracyclines and chloramphenicol, treatments which had no apparent effect on the amount of S. typhimurium and E. coli excreted. Much of the antibiotic resistance encountered was determined by R factors, a particular R factor usually being found in the E. coli populations of individual chickens before it was found in their S. typhimurium populations. No S. typhimurium or E. coli were isolated that possessed R factors determining resistance to polymixin, furazolidone or trimethoprim. No S. typhimurium or E. coli were isolated that were polymixin-resistant and no S. typhimurium that were furazolidone-resistant. The few trimethoprim-resistant S. typhimurium isolated were thymine-dependent.The feeding of diets containing the higher concentrations of trimethoprim/sulphadiazine, neomycin, furazolidone or ampicillin for 9 days reduced the amount of S. typhimurium excreted. After the withdrawal of these diets, the amount of S. typhimurium excreted increased to the numbers found in chickens given ordinary diets throughout; the chickens that had been given trimethoprim/sulphadiazine or furazolidone did not remain faecal excreters of S. typhimurium longer than the chickens that had been given ordinary diets. Similar results were obtained with trimethoprim/sulphadiazine when the start of the 9-day treatment period was delayed for an extra 9 days or when it was extended to 18 days.
Bacterial contamination in a modern operating suite. 1. Effect of ventilation on airborne bacteria and transfer of airborne particles
Authors: Hambraeus Anna , Bengtsson Stellan , Laurell Gunnar 
Published: May 2009

SUMMARYThe effect of ventilation on airborne contamination was studied in a new operating suite containing operating rooms with conventional ventilation (17−20 turnovers/h) and operating rooms with zonal ventilation, where the turnover in the central part of the room was˜80/h. The efficacy of the ventilation was first examined with gas tracer experiments and found satisfactory. Experiments using potassium iodide particles showed the transfer between adjacent rooms in the suite to be less than 10−3% with closed doors and from 1% to 2·5 × 10−2% when the doors were opened once a minute. The transfer between two adjacent operating rooms was calculated to be˜10−4%. There is thus little risk of spread of airborne infection between operating rooms.Experiments with potassium iodide particles showed that in operating rooms with zonal ventilation the particle concentration in the centre of the room was about one-tenth that in the periphery; in conventionally ventilated operating rooms the concentration was about one-half. With bacteria-carrying particles generated by human activity the concentration in the centre of operating rooms with zonal ventilation was about half that in the periphery both during experimental activity and operations; in conventionally ventilated operating rooms it was about equal in both cases. Bacterial counts at the periphery were found to be lower in rooms with zonal ventilation (˜ 50 c.f.u./m3) than in conventionally ventilated (˜ 70 c.f.u./m3).
Isolation of myxoviruses from dead birds arriving at Heathrow Airport, London
Authors: Alexander D. J. , Allan W. H. , Sillars T. 
Published: May 2009

SUMMARYForty-four haemagglutinating viruses were isolated from the pooled tracheal/cloacal swabs of the dead birds from 170 consignments of caged birds arriving at Heathrow Airport over a period of 6 months. Two isolates were identified as Newcastle disease virus but the remaining 42 were all identified as influenza viruses with Hav 7 Neq 2 antigens. All the consignments from which influenza viruses were isolated originated in India but had widespread destinations. The NDV isolates were from birds originating in central America and destined for Japan.
Identification of pregnancies at risk from cytomegalovirus infection
Authors: de Silva L. M. , Kampfner G. L. , Lister C. M. , Tobin J. O.'H. 
Published: May 2009

SUMMARYThe fluorescent antibody technique was used for the identification of specific cytomegalovirus IgM in the sera of twenty-four of 1065 unmarried pregnant women. Seventeen of them were followed to term and five infected infants were identified. Two other infants had CMV IgM in neonatal serum samples but virus excretion was not demonstrated. The congenital infection rate in this study was 5·3 per 1000 births by virus excretion and 7·9 per 1000 if cases with specific IgM are included; from previous studies a rate of 8·8 per 1000 was expected. The reasons for the lack of relationship between specific IgM in the mothers' serum and infected babies is discussed.
Isolation ofCampylobacter fetusfrom recent cases of human vibriosis
Authors: Hallett A. F. , Botha P. L. , Logan A. 
Published: May 2009

SUMMARYCampylobacter fetuswas isolated from five recent cases of human vibriosis, of which two were adults and three were children. One adult presented with pericarditis and the other with recurrent pyrexia.Campylobacter fetussubsp.intestinaliswhich resembled cattle strains serologically, was isolated under CO2or anaerobic conditions from blood cultures of these patients. Two of the three children had kwashiorkor and the third was only 8 days old. Isolates identified asCampylobacter fetussubsp.jejuniwere cultured from blood of these patients, two of whom had diarrhoea. Three patients succumbed, despite adequate antibiotic therapy. The epidemiology of the disease is discussed and it is suggested that infection may have been from the patients' own flora.
Serotype-related enterotoxigenicity inEscherichia coliO6.H16 and O148.H28
Authors: Scotland Sylvia M. , Gross Roger J. , Rowe Bernard 
Published: May 2009

SUMMARYThe ability of certainEscherichia colistrains to produce enterotoxin is determined by transmissible plasmids. It is therefore possible that anyE. colistrain might be able to acquire such a plasmid and that the correlation between enterotoxigenicity and serotype might be random. However, recent studies show that the enterotoxigenic strains so far described belong to a restricted range of serotypes. Enterotoxigenic strains ofE. coliO6.H16 andE. coliO148.H28 have been associated with outbreaks of diarrhoea in several countries, therefore strains ofE. colibelonging to these serotypes were selected for further study.Twenty-three strains ofE. coliO6.H16 and 14 strains ofE. coliO148.H28 were examined; 20 strains ofE. coliO6.H16 and all 14 strains ofE. coli0148.H28 were enterotoxigenic but strains ofE. coliO6 with flagellar antigens other than H16 and strains ofE. coliO148 with flagellar antigens other than H28 were not enterotoxigenic. The examination of single colony subcultures derived from theE. coliO6.H16 strains showed that in some strains loss of enterotoxigenicity had occurred in a proportion of colonies.
Clonal distribution of resistance plasmid-carryingSalmonella typhimurium, mainly in the Middle East
Authors: Anderson E. S. , Threlfall E. J. , Carr Jacqueline M. , McConnell Moyra M. , Smith H. R. 
Published: May 2009

SUMMARYStrains ofSalmonella typhimuriumof predominantly Middle Eastern origin, but distributed from England to India, were found to carry at least three types of resistance plasmid. The most important was initially identified as an FIplasmid by compatibility tests, but differs from the F factor on the one hand and the FIfactors R162 and CoIV on the other. The three groups of FIplasmids can be distinguished by their compatibility reactions with the MP10 plasmid ofS. typhimurium(Smith, Humphreys, Grindley, Grindley & Anderson, 1973) and group H1factors: the F factor is unilaterally incompatible with group H1(Smith, Grindley, Humphreys & Anderson, 1973; Anderson, 1975b); the FIfactors are compatible with MP10 and group H1and FImefactors are incompatible with MP10 but compatible with H1. The majority ofS. typhimuriumcultures belonged to phage type 208; most of those that did not, belonged to types related to 208. Only a minority of their FImeplasmids were autotransferring. The remainder were mobilizable by F-like plasmids, and by group H1and H2factors, but not by thefi–I1facter δ, or by plasmids of the I2, B, P, W, N andcom7 groups. The compatibility reactions of the autotransferring F1meplasmids were identical with those of the non-transferring members of the group, and both were large, single-copy plasmids.TheS. typhimuriumstrains of this series carried A or AK, and SSu resistance determinants: small, probably multicopy, non-transferring plasmids similar to those originally described in phage type 29 ofS. typhimurium(Anderson & Lewis, 1965b).TheseS. typhimuriumcultures probably represent a clone of wide geographical distribution. The accurate epidemiological study of such clonal outbreaks requires, in addition to phage typing, precise identification of the plasmids harboured by the epidemic strains, and may have to be carried to the molecular level.FImeplasmids were identified in other drug-resistant salmonellas, notably in a strain ofS. wienwhich caused large outbreaks of mainly paediatric infection in Algeria, and also spread to Britain. An FImeplasmid was found inS. typhiphage type 44 from Algeria, in which the phage-restricting properties of the plasmid are responsible for the specificity of the type.