bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effect of long-term exposure to cigarette smoke on the height and specificity of the secondary immune response to influenza virus in a murine model system
Authors: Mackenzie J. S. , Flower R. L. P. 
Published: May 2009

SUMMARYThe effect of long-term exposure to cigarette smoke on the height and specificity of the secondary humoral immune response to influenza was investigated in a murine model system. It was shown that if mice were pre-immunized with a sub-lethal infection of influenza virus and then exposed to cigarette smoke daily for 36 weeks, they were able to mount a secondary immune response of normal height on subsequent challenge with the homologous virus strain. The response, however, was less specific than that elicited in control mice, with high titres of cross-reacting antibody by haemagglutination-inhibition to the following strain in the same antigenic series. Recall of antibody to the previous strain in the antigenic series was not observed in either control or smoke-exposed animals. These results serve to correct an earlier discrepancy between the murine system and human studies in which the response to influenza infection in mice was depressed by prolonged exposure to cigarette smoke, whereas in man the response of smokers did not differ significantly from that of non-smokers. This apparent discrepancy had been caused by a lack of previous experience of influenza in the mice, which had therefore mounted a primary response, compared with the secondary response observed in the human studies.
Measles in monkeys: an epidemiological study
Authors: MacArthur J. A. , Mann P. G. , Oreffo V. , Scott G. B. D. 
Published: May 2009

summaryThis study describes aspects of measles in non-human primates. Monkeys infected before importation are shown to produce non-immune offspring in captivity in England. The high antibody titres found in most recently imported monkeys decline slowly during captivity in England. While measles is often fatal to monkeys, we have described an outbreak in which a number of symptomless infections occurred. Histological examination of fatal cases produced evidence of infection in the wall of the urinary bladder in one monkey. The close similarity between measles in humans and monkeys has been confirmed. It is considered that the study of infection among the latter may have significance for the former.
Food poisoning in hospitals in Scotland
Authors: Sharp J. C. M. , Collier P. W. , Gilbert R. J. 
Published: May 2009

summaryA review of 50 hospital-based outbreaks of food poisoning which were reported in Scotland during 1973–7, is described. At least 1530 persons consuming hospital-prepared food were involved. Thirty-one episodes were associated with Clostridium perfringens (C. welchii), 11 were due to food-borne salmonella infection, three to enterotoxigenic Staphylococcus aureus, and five incidents were of undetermined aetiology. This differs noticeably from the experience in England and Wales where salmonellas appear to predominate as the main cause of hospital outbreaks. Twenty-two incidents occurred in hospitals for psychiatric or mentally subnormal patients, and ten others were located in geriatric units. Only 33 hospitals were involved in the 50 outbreaks as nine hospitals experienced two or more episodes.The role of the hospital in the occurrence of food poisoning may be over-emphasized in comparison with other catering establishments, as outbreaks are more readily recognized and laboratory facilities are usually available for investigation, but it is also believed that many episodes may not be reported. The peculiar problems of the hospital-catering service and particularly those of the older long-stay hospitals, are discussed in relation to preventive measures which would minimize the hazards of food poisoning.
The effect on the virulence and infectivity ofSalmonella typhimuriumandSalmonella gallinarumof acquiring antibiotic resistance plasmids from organisms that had caused serious outbreaks of disease
Authors: Williams Smith H. , Tucker J. F. 
Published: May 2009

summaryAntibiotic resistance plasmids from organisms that had caused serious epidemics, including those responsible for epidemics of chloramphenicol-resistant typhoid fever and dysentery in Central America, were transferred to a strain ofSalmonella typhimuriumand ofSalmonella gallinarum. The virulence and infectivity of these R+forms were then compared with the R−parent forms in orally inoculated chickens.None of the R+forms were more virulent than their R−parent forms. The mortality rates they produced were either the same as or less than that of their R−parent forms. The mortality rates were not increased by feeding the chickens on diets containing antibiotics against which the plasmids provided resistance.The removal of the plasmids from some R+forms of decreased virulence was not accompanied by any alteration in virulence, indicating that they were less virulent mutants of the parent strain that had conjugated preferentially. In other cases their virulence was increased, indicating that the very possession of the plasmid was involved in their decreased virulence. Of four forms of theS. gallinarumstrain harbouring the plasmid that had been incriminated in the Central American dysentery outbreak, one was as virulent as the parent R−form and the other three were less virulent. Preferential conjugation by an avirulent mutant was responsible for the lack of virulence of one of them but the very possession of the plasmid appeared responsible for the decreased virulence of the other two. The decreased virulence of de-repressed F+and I+forms of theS. typhimuriumstrain was increased to that of repressed F+form and of the parent form by plasmid removal.Organisms of the R+forms of theS. typhimuriumstrain were not excreted in larger amounts or for longer periods of time by infected chickens than organisms of the R−parent form were. Neither did organisms of the R+forms of this strain or theS. gallinarumstrain spread more rapidly or more extensively from infected chickens to in-contact chickens than organisms of the R−parent forms did. When antibiotics against which the infecting R+organisms provided resistance were included in the diet of these chickens the R+organisms were usually excreted in greater amounts, for longer periods of time and spread more rapidly and more extensively from the infected chickens to the in-contact chickens.
The antibody response in Legionnaires' disease
Authors: Nagington J. , Wreghitt T. G. , Tobin J. O'H. , Macrae A. D. 
Published: May 2009

summaryFrom 22 patients with Legionnaires' disease, 86 sera were examined for specific serotype 1 IgM and IgG antibodies by the indirect immunofluorescence technique.No antibody was detectable until 8 days or more from the onset of symptoms. When produced the amount was widely variable and remained detectable for periods from less than 34 days to more than 1 year.Initially IgM antibody predominated, ten patients produced only IgM in the first 21 days, six produced only IgM in the first 28 days and three did not produce IgG at any time. One patient, and possibly a second, produced only IgG antibody.Since IgM antibody was still present in one patient after a year it is important not to accept the presence of this as evidence of very recent infection.It is advisable that any type of serological test for L. pneumophila infection should detect the production of both IgM and IgG antibodies.
Incidence of bluetongue virus precipitating antibodies in sera of some domestic animals in the Sudan
Authors: Eisa M. , Karrar A. E. , Elrahim A. H. Abd 
Published: May 2009

To determine the presence and prevalence of bluetongue (BT) infection in a variety of domestic animal species in different geographical regions of the Sudan, a serological study using the agar gel precipitation technique was initiated. A total of 2142 serum samples were examined. Of the numbers tested approximately 28% of sheep, 11.2% of goats, 8% of cattle and 4.9% of camels were positive for group-specific antibodies to BT virus antigen, indicating previous exposure to BT infection. None of the samples tested from horses or donkeys were positive. The findings suggest that the disease is widely distributed in most parts of the Sudan where possible insect vectors prevail and may be endemic in sheep in Juba District, Equatoria Province, Southern Region. Goats appeared to have some degree of resistance to infection compared with sheep, and there seemed to be no significant differences in positive rates between farm and free-range cattle.It is concluded that BT infection may cause clinical disease in sheep, while it is probably subclinical or inapparent in goats, cattle and camels of the Sudan.
A bacteriological survey of sanitary dressings, and development of an effective means for their disposal
Authors: Lucas C. M. , Mendes M. F. 
Published: May 2009

SUMMARYA microbiological survey of over 400 sanitary dressings is reported: large numbers of bacteria are present, including species indicative of faecal contamination. The need for an effective bactericide in chemical bin exchange systems is thus demonstrated. Screening trials of several candidate formulations have been undertaken: buffered sodium metabisulphite, releasing sulphur dioxide as a vapour-phase bactericide, has now been introduced as an effective bin exchange system.
Inactivation of viruses in municipal effluent by chlorine
Authors: Hajenian H. G. , Butler M. 
Published: May 2009

SUMMARYThe influence of pH arid temperature on the efficiency of chlorine inactivation of two unrelated picornaviruses in a typical urban wastewater effluent was examined. Temperature, unlike pH, had relatively little effect on the rate of inactivation. The pH effect was complex and the two viruses differed. The f2 coliphage was more sensitive to chlorine at low pH, but at all values there was a threshold above which additional chlorine resulted in very rapid inactivation. The amount of chlorine required for this was less at low than at high pH, although at pH values above 7 the extent of inactivation was about the same. There was no apparent correlation between pH and rate of inactivation of poliovirus but there was a suggestion that at a pH close to the isoelectric point of the virus it was less sensitive to chlorination.
Contaminated medicaments in use in a hospital for diseases of the skin
Authors: Baird Rosamund M. , Awad Z. A. , Shooter R. A. , Noble W. C. 
Published: May 2009

SUMMARYTopical medicaments used by patients with diseases of the skin were examined for microbial contamination. Ps. aeruginosa was isolated from stock pots of a diluted emulsifying ointment used as a soap substitute in the bath. Cross-con tamination between patients and medicament was subsequently shown to have occurred.
Further observations on the effect of feeding diets containing avoparcin, bacitracin and sodium arsenhlate on the colonization of the alimentary tract of poultry by salmonella organisms
Authors: Smith H. Williams , Tucker J. F. 
Published: May 2009

SUMMARYThe continuous administration of food containing 10 mg/kg of avoparcin to groups of 28 chickens in contact with five chickens experimentally infected with a nalidixic acid-resistant (nalr) mutant of a salmonella strain strongly favoured the colonization of their alimentary tracts with salmonella organisms. Bacitracin, 10 mg/kg, either had no effect or only slightly favoured salmonella colonization and sodium arsenilate usually hindered it.
Aspects of heat inactivation of foot-and-mouth disease virus in milk from intramammarily infected susceptible cows
Authors: Leeuw P. W. De , Tiessink J. W. A. , Bekkum J. G. Van 
Published: May 2009

SUMMARYIn skim milk obtained from susceptible cows after intramammary and intravenous inoculation (primary infected milk), foot-and-mouth disease (FMD) virus type 01was slower inactivated by heat treatment than virus that had been added to pre-exposure skim milk.Residual virus infectivity in heated primary infected milk was more efficiently detected in bovine thyroid cell cultures than in secondary pig kidney (PK2) cell cultures.Untreated primary infected milk was found to inhibit both FMD-virus and vesicular stomatitis virus plaque formation in PK2cells, suggesting the presence of interferon. The results of further tests confirmed that the interfering activity in unheated primary infected milk was indeed caused by an interferon.Interferon excretion in primary infected milk was investigated using a series of milk samples from three cows. Maximum interferon titres were found after 24 h, coinciding with or shortly after the first virus excretion peak. The results are discussed with particular reference to the use of primary infected milk in studies of the thermal inactivation of FMD-virus.
Isolation and classification of sixteen strains of saprophytic leptospires
Authors: Cinco M. , Coghlan J. D. , Matthews P. R. J. 
Published: May 2009

SUMMARYSixteen strains of leptospires were isolated from surface water (14 in England and 2 in Italy) and were classified. They were all saprophytic, and nine of them belonged to known serovars: the others were found to represent new serovars within already known serogroups.
Commercial milk products and indigenous weaning foods in a rural West African environment: a bacteriological perspective
Authors: Barrell R. A. E. , Rowland M. G. M. 
Published: May 2009

SUMMARYTwo commercially available baby milks, one ‘biologically acidified’, the other ‘non-acidified’, and a traditional weaning food, millet gruel, were prepared and stored under village conditions in West Africa. Increases in total colony count and in number ofBacillus cereus, Clostridium welchii, Staphylococcus aureusandEscherichia coliwere determined in these products when stored as commonly practised at ambient temperatures over a period of 8 h. Poor hygiene during preparation was indicated by readily detectable numbers of coliforms andE. coliin freshly prepared samples of each of the milks, though the cooked local gruel seemed less vulnerable in this respect. The rate of increase in the numbers of these organisms was lower in the acidified milk when prepared with unboiled water containing high numbers of coliforms andE. coli. Increases in total colony count and in numbers ofStaph. aureuswere also less marked in the acidified milk. When food was not eaten soon after preparation the problem of bacterial overgrowth was as great with the local gruel as with the considerably more nutritious reconstituted milks.
Isolation and properties of an RNA fraction present inBrucellaculture supernatants
Authors: Corbel M. J. , Brewer R. A. 
Published: May 2009

SUMMARYThe supernatant fluids of batch and continuous cultures ofBrucellastrains contained up to 100 mg/i of soluble RNA which could be recovered by precipitation with lysozyme. This RNA fraction had many of the properties of ribosomal RNA and was single-stranded, sensitive to ribonuclease, with an approximate sedimentation constant of 5S, a molecular weight of about 35000 daltons and an adenine; guanine; cytosine; uracil content of 17·5 26·5 33; 23 mol% respectively. RNA fractions from lysozyme precipitates evoked high titres ofBrucellaagglutinins on injection into rabbits and induced acute inflammatory responses in guinea-pig skin. Highly purified RNA fractions prepared by phenol extraction of lysozyme precipitates did not evoke antibodies toBrucella abortus.
The epidemiological type identification ofSerratia marcescensfrom outbreaks of infection in hospitals
Authors: Pitt T. L. , Erdman Y. J. , Bucher C. 
Published: May 2009

SUMMARYA study of serological, bacteriocine and phage typing ofSerratia marcescenswas made. Specific O-antisera of adequate titre were relatively simple to prepare but H-antisera exhibited many heterologous agglutination reactions amongst the type strains. Most of these cross-reactions were not reproduced when immobilization tests with H-sera were performed. Direct haemagglutination tests were used to establish the presence of fimbriae amongst the H-type strains and the results of agglutination tests with non-fimbriate variants of strains indicated that fimbrial antibody in high titre was present in some sera.Replicate typing of 100 pairs of cultures by the phage-typing method indicated that small variations in pattern were common and that larger variations occurred occasionally. Therefore differences in pattern of less than two strong reactions should not be taken as evidence that strains can be distinguished.Cultures ofS. marcescens, 273 in total, from six outbreaks of infection in British and European hospitals were typed by O-serology, H agglutination and immobilization tests, phage typing and bacteriocine susceptibility by a cross-streaking method. The typability of strains by each method was high but the results suggested that no single method was sufficiently discriminating to be used alone for typing. Comparison of the H-type and typing patterns of members of the same O serogroup from incidents of infection showed that reliable results were obtained by H-typing or by phage and bacteriocine typing after the application of the appropriate ‘difference’ rule.The greatest discrimination between strains of the same 0-group was obtained by the use of H-typing or phage typing.
The Northumberland epidemic of foot-and-mouth disease, 1966
Authors: Sellers R. F. , Gloster J. 
Published: May 2009

SummaryThe spread of foot-and-mouth disease during an epidemic in Northumberland in July, August and September 1966 was analysed. Although strong emitters, for example pigs, were not involved, in 18 of the 32 outbreaks spread could be attributed to the airborne route and in another 4, spread by this route was the most likely. Airborne spread was in general between 1 and 8 km but on two occasions as much as 20 km. Other means of spread included movement by animals, people and vehicles and carriage of virus between animals in neighbouring fields. No spread by milk or milk lorries took place. Sheep were involved in 9 farms; on each, lesions older than 48 h were found and it is likely that the sheep were the source of virus for other animals, especially cattle, on the farm and on neighbouring farms. The analysis suggests that control measures such as slaughtering direct contacts, as used in this epidemic, or ring vaccination as well as movement control would be effective in limiting spread.
Immunity to salmonella infection in mice
Authors: MacLeod D. R. E. 
Published: May 2009

Experiments on immunity produced by vaccine were carried out in mice with two strains of salmonella.Against intraperitoneal challenge protection was such that 40–80 % of vaccinated mice survived a dose that killed almost all controls. This level of immunity appeared to be maintained with little change for at least 5–7 months. An explanation for this stability is suggested.Against infection by the natural route, either by direct feeding or by exposure to infected animals, protection from vaccine was of a comparatively low order.Resistance to infection by an artificial route was, therefore, not a measure of resistance to infection by the natural route.
Titration of the virus of foot-and-mouth disease in culture
Authors: Brooksby J. B. , Wardle Ella 
Published: May 2009

A technique is presented for the titration of the virus of foot-and-mouth disease in culture in surviving epithelial tissue from the tongues of cattle. The cultures are incubated in cups on Perspex plates, and the detection of virus multiplication is by a complement-fixation test made on the culture in each cup.On the basis of comparative titrations in culture and in cattle, the method has been found to be as sensitive for the detection of virus as the titration by intradermal inoculation of the tongue of cattle. The method can also be applied in the detection of antibody in neutralization tests.We wish to record our thanks to Messrs E. Scoates and P. Mitchell for their technical assistance, and to Messrs H. M. Smith, R. H. Compton and R. L. Jackson for their part in the design and fabrication of various bottle rotators, plate shakers, Perspex lids and the inoculating box.
Reactions of T Vi and Ballerup Vi haptenes with antisera against Vi-coated erythrocytes
Authors: Chu David Chi-Yen , Hoyt Robert K. 
Published: May 2009

1. T Vi-coated rabbit erythrocytes, when injected into rabbits, stimulate the production of a (pure) Vi antiserum.2. The T Vi extract was found to be heat-stable with respect to antigenicity and agglutinability, as shown by means of coated erythrocytes.3. By means of cross-absorption tests it was shown that the Vi antigen of S. typhi differs from the Vi antigen of the Ballerup organism.4. The need for caution in relying on resistance to heat as a character of groups of antigens is emphasized.We wish to thank Dr P. R. Edwards, of the Communicable Disease Centre, U.S.P.H.S., and Dr Alcor S. Browne, California State Department of Health, for supplying certain of the cultures and specimens of typing serum used in these studies.
Factors affecting the formation and oxidation of sulphides in a polluted estuary
Authors: Wheatland A. B. 
Published: May 2009

Factors affecting the formation and destruction of sulphide in the Thames Estuary have been discussed. Measurements of oxidation-reduction potentials show that the effect of oxygen in the water on conditions in deposits of mud is limited to the surface layer. The rate of formation of sulphide increases with temperature, doubling approximately for each 10° C. rise. Reduction of sulphate to sulphide will occur at temperatures as low as 5° C., but even at 25° C. is inhibited by traces of dissolved oxygen. Mud in suspension in the estuary can produce as much sulphide as compact layers of similar mud which might be more anaerobic.Oxidation of sulphide in the Thames Estuary is shown to be of a purely chemical nature; the rate of oxidation, when oxygen is present, is increased by the presence of suspended matter and iron. In the Thames Estuary, however, the rate is limited by the rate at which oxygen enters the water.Much of the experimental work described in this paper was carried out by Miss A. Laird, Mr A. E. Sutton and Mr R. B. Peel of this Laboratory. The paper is published by permission of the Department of Scientific and Industrial Research.
A comparison of the soluble antigen production by tissues infected with preparations of extracellular and intracellular influenza virus
Authors: Beale A. J. 
Published: May 2009

1. The production of soluble antigen in the chorioallantoic membranes at 6 hr. can be used to measure the infectivity of influenza virus preparations.2. Intracellular virus is much more infective when tested by soluble antigen production at 6 hr. than when tested by conventional methods.3. It is suggested that intracellular virus differs from extracellular because more virus particles per cell are required to initiate infection.The author is greatly indebted to Dr L. Hoyle for his advice and encouragement throughout this work. Mr G. Field gave valuable help with the mathematics.
Reversed passive anaphylaxis in the guinea-pig
Authors: van den Ende M. 
Published: May 2009

Attempts to demonstrate reversed passive anaphylaxis in the guinea-pig with crystalline egg albumin as sensitizing antigen have been uniformly negative.When purified anti-pneumococcal antibody globulin was used as sensitizing antigen, reversed anaphylactic shock could be elicited in guinea-pigs by the intravenous injection of precipitins for the antibody globulin.The mild reactions which could be elicited when the total globulins from the serum of normal rabbits were used as sensitizing antigen are probably dependent on the presence of small amounts ofyglobulin.Reversed passive anaphylaxis, like direct anaphylaxis, is dependent on a cellular mechanism, and the success of experiments in which rabbit antibody globulin was used as sensitizing antigen depends on the acceptability of the antibody to the cells of the guinea-pig's tissues.Antigenic differences between antibody globulins and total normal globulins from rabbit serum are noted.