bluuebunny/crossref_metadata_2025 huggingface dataset:
Natural And Immune Bactericidins For The Gonococcus
Authors: Abdoosh Y. B.
Published: May 2009

1. Normal human sera have no natural bactericidins active against strains of gonococci.

2. Normal sera from eleven other mammalian species showed a powerful bactericidal action against various strains of gonococci.

3. The serological heterogeneity of the gonococcus group revealed by agglutination and complement fixation is again demonstrated in the bactericidal test with immune antiserum.

4. There is a steady rise in the incidence of positive bactericidal action in the sera of patients following the progress of infection with the gonococcus.

5. The probable significance of these bactericidins, natural and immune, discussed.

Acknowledgments. I wish to express my gratitude to Dr Ledingham for the facilities for work granted me at the Lister Institute and to Dr Schiitze for his kind help and critical advice during the progress of this investigation.
A Gas-Producing Variety Of Bacterium Alkalescens (Andrewes)
Authors: Bamforth J.
Published: May 2009

In the autumn of 1934 I received from Dr A. R. D. Adams, Superintendent of the Bacteriological Laboratory at Mauritius, 163 cultures of organisms. These had been isolated by him from the faeces of the inmates of the Beau Bassin Prison and Reformatory in a research on the intestinal flora and fauna of the general population in that island. In the course of the bacteriological examination the specimens of faeces had been cultured on plates of Endo's medium and incubated for 24 hours, at the end of which time non-lactose-fermenting organisms were picked off. A number of these strains were identified by Dr Adams as belonging to the typhoid, paratyphoid, or dysentery groups. One hundred and sixty-three strains which did not fall into these groups were sent to me for investigation.
Statistical Study Of The Sex Ratio At Birth
Authors: Russell W. T.
Published: May 2009

That the number of male births always exceeds that of females is well known to students of vital statistics, but the biological law responsible for the phenomenon has not yet been adequately determined though various theories have been offered in explanation. It has been suggested that it resulted from a high male conception rate which, although modified by an excess mortality of male embryos, nevertheless produced a masculinity of matured births. In more recent times the conclusions drawn by MacDowell & Lord (1925, 1925a) from their experimental studies with mice have failed to support this view. They claimed that there was no correlation between the pre-natal mortality and the masculinity of live births, that the primary ratio at conception was almost identical with that at birth. These contentions were criticized by Parkes (1923, 1926), who, whilst maintaining the doctrine that the ante-natal mortality of mice “falls preponderatingly upon the males”, stated “that it is quite obvious that a great deal more information is required before any coherent story of the factors governing the sex ratio at birth in the mouse (and all other mammals) can be put together”.
Boric Acid As A Selective Bacterio-Static Agent
Authors: Blair E. Maud Mcv.
Published: May 2009

A fluid medium is described, containing in every 100 c.c. of peptone water 0·25 g. lactose, 0·5 g. boric acid and 1 g. sodium sulphite (anhydrous). It shows a marked selective action.

The test gives satisfactory readings within 24 hours of incubating at 37°C. I am of the opinion that all strains capable of growth in this medium may be regarded as of definite sanitary significance; they are most likely of faecal origin, while those which fail to grow are of minor sanitary importance.

I hope that the boric sulphite test may prove a useful adjunct to the bacteriological examination of samples of water.
Passive Anaphylaxis following the immediate injection of Antigen after Antiserum
Authors: Dean H. R. , Williamson R. , Taylor G. L.
Published: May 2009

1. Our experiments show that an intravenous injection of antigen immediately after an intravenous injection of antiserum in the guinea-pig were followed by:

(a) Acute shock and death within 5 min. The signs and post-mortem appearances were indistinguishable from acute anaphylactic shock as typically seen in the guinea-pig. Some control animals injected with antiserum only died in a way similar to those which received both antiserum and antigen. These are discussed in detail in the body of the paper.

(b) Delayed shock and death some hours later. The post-mortem appearances were those of gastro-intestinal congestion and haemorrhage resembling the changes seen in dogs dying of anaphylactic shock. Such changes were never seen in the control animals.

(c) Recovery. Practically all the animals which recovered had symptoms of respiratory embarrassment immediately following the injections of anti-serum and antigen and many had later symptoms of abdominal shock. The animals which were given an injection of antiserum only rarely had any symptoms and never abdominal symptoms.

2. It is necessary to test the antisera used by control inoculation since some antisera aretoxic.
A comparative study of the reaction in vivo and in vitro of rabbit tissues to infection with bovine tubercle bacilli: Part I. Observations on rabbit spleen infected in vitro
Authors: Fell Honor B. , Brieger E. M.
Published: May 2009

1. The effect of virulent bovine tubercle bacilli on rabbit tissue in vitro was studied.

2. When normal spleen cultures were infected in vitro the cells actively phago- cyted the bacilli. At first the phagocytes tolerated the organisms, and in the course of their wanderings spread the infection throughout the tissue. Some infected cells even underwent mitotic division.

3. Eventually the infected cells broke down, and the freed bacilli continued to grow in the tissue. Fourteen days after infection, outgrowth had usually ceased and the explants were almost completely replaced by bacilli.

4. Actively growing spleen cultures were unable to suppress even a slight infection with virulent bovine bacilli.

5. No tubercles were formed in the cultures.

6. There were no indications ofan exotoxic action of the bacilli on the cells in tissue culture, an densely infiltrated explants were often surrounded by a large zone ofoutgrowth.
Studies on respiratory infection: III. Experiments with Brucella suis
Authors: Druett H. A. , Henderson D. W. , Peacock S.
Published: May 2009

The infectivity of Brucella suis for the guinea-pig by the respiratory route has been studied. Br. Suis was dispersed in airborne particles of various sizes from single organisms to 12μ in diameter, and it was found that the infectivity decreased 600-fold with increasing particle size within this range. It is suggested that this is due to the ability of Br. Suis to multiply rapidly on the surface of the lower reaches of the respiratory tract.
Strain differences in the Newcastle disease virus
Authors: Macpherson L. W. , Swain R. H. A.
Published: May 2009

The biological characters of eight strains of the Newcastle disease virus, isolated in different parts of the world between 1933 and 1951, have been studied and compared in detail.

Two types of the virus have been distinguished, one from the Newcastle disease prevalent in Europe and Australia, the other from that occurring in the United States of America.

Viruses of the first type are highly virulent, multiply rapidly and successively develop the properties of infectivity, haemagglutination and haemolysis. Their haemagglutination pattern is constant and wide; they profoundly modify human group O erythrocytes, and they are antigenically homogeneous.

Viruses of the second type are of weaker virulence. They grow at a slower rate in the allantoic cavity of the chick embryo, and the development of their characters is retarded; they have a reduced haemagglutination pattern and only a minimum capacity to modify human group O cells. Antigenically strains of the second type are homogeneous.

From haemagglutination inhibition and absorption studies it is concluded that major antigens are shared by both types, and that the first type possesses one or more antigens lacking in the second.

The highly virulent Canadian TWISS strain possesses the characters of the first type and an antigenic constitution with features of both types.

The significance of the results is discussed in relation to the ecology of Newcastle disease.
Infectivity titrations of myxoma virus in the rabbit and the developing chick embryo
Authors: Fenner Frank , McIntyre G. A.
Published: May 2009

Titrations of the same preparations of myxoma virus have been made on the chorioallantoic membranes of developing chick embryos and by the intradermal inoculation of rabbits. Six strains of widely differing virulence for the rabbit were used.

No differences were found in the infectivity of different strains for either the rabbit or the egg, even though the severity of the symptoms produced in the rabbit varied greatly with different strains; and although some had never previously been inoculated in eggs and one had been subjected to seventy-five serial passages on the chorioallantoic membrane.

The egg was less sensitive than the rabbit, the mean number of infections per dose for rabbits relative to eggs being 2.46, taken over all strains. This ratio did not differ significantly between strains of myxoma virus.

There was evidence of some host variation in rabbit susceptibility and a great deal of variation in egg susceptibility. The maximum value for the average probability that an infectious unit would produce a lesion in the rabbit skin was about 0.6, and the maximum value for the average probability that an infectious unit would produce a pock on the chorioallantoic membrane was 0.25.

Titration of several closely spaced dilutions of different strains of the virus on the chorioallantoic membrane showed a reasonably close approximation to a proportional relationship between the pock count and the virus dilution. The change with dilution in the proportion of failures to infect rabbits approximated to expectation. Both lines of evidence are consistent with the hypothesis that a pock or skin lesion is initiated by one infective unit of virus, and that the infective unit is stable with dilution.
Intracellular growth of some viruses of the pox group. An electron microscopic study of infected chick chorionic cells
Authors: Flewett T. H.
Published: May 2009

Sections of chorio-allantoic membranes fixed at intervals after infection with large doses of vaccinia virus showed almost homogeneous areas appearing in the cytoplasm after 4 hr.; these areas contained immature forms of virus which had a thin surface membrane and an eccentric ‘nucleoid’, and were surrounded by mitochondria. Mature forms of virus, having a larger central nucleus-like structure and a thicker cortex, were first found in areas of virus growth 10 hr. after inoculation. Similar immature and mature forms were found in cells infected with fowl-pox, myxomatosis and ectromelia viruses. It is concluded that the immature forms are of low infectivity or not infective.
The use of live vaccines in experimental Salmonella gallinarum infection in chickens with observations on their interference effect
Authors: Smith H. Williams
Published: May 2009

1. A good immunity was produced in chickens against oral infection with Salm. gallinarum by the use of either of two live attenuated vaccines, one smooth, 9S and one rough, 9R. Dead vaccines had little or no effect.

2. The immunity possessed by chickens vaccinated with 9R at 7 weeks of age commenced to wane 12 weeks later. Chickens similarly vaccinated with 9S were completely immune 4, 12 and 34 weeks later. When tested during the active laying period (at 20 weeks after vaccination) their immunity, although substantial, was not complete.

3. Vaccine 9R did not produce demonstrable agglutinins against smooth Salm. gallinarum in chickens. It was non-lethal to 1-day-old chicks and was never found to revert to the smooth virulent form in vitro or in vivo. By contrast, vaccine 9S produced agglutinins and was lethal for 1-day-old chicks, its virulence not being increased by passage. No deaths were ever observed when this vaccine was used in either chickens of 5–12 weeks old or laying hens.

4. Although both vaccines produced a good immunity when employed in laying hens, vaccination with 9S was accompanied by a marked reduction in egg production; this was not the case with 9R.

5. An immunity of the interference type was also evoked by both live vaccines. This immunity was still produced to some extent in chickens injected with 9S, 2 days after they were infected with Salm. gallinarum by mouth.

6. The interference effect could not be produced by the use of either dead Salm. gallinarum vaccines or certain non-specific substances. The intravenous injection of indian ink had a marked adverse effect on the course of the disease. Injecting chickens with a virulent strain of Bacterium coli at the same time as they were infected with Salm. gallinarum resulted in the latter infection running a milder course than would normally have been expected.
The Part Played by Woodland Mosquitoes of the Genus Aëdes in the Transmission of Myxomatosis in England
Authors: Muirhead-Thomson R. C.
Published: May 2009

1. Myxomatosis was first recorded in England in October 1953 and persisted over the following winter. It was anticipated that an epizootic, similar to those in Australia, would develop during the spring or summer of 1954 and that mosquitoes might be the principal vectors. A study of the sylvan mosquitoes in the area of the first myxomatosis outbreak was therefore made, from April 1954 onwards.

2. These mosquitoes (Aëdes spp.) overwinter as larvae, pupate in early May and are adult from mid-May to September. Throughout this period, in 1954, myxomatosis spread slowly in the study area and infected rabbits were abundant.

3. Despite the presence of large numbers of Aëdes (particularly A. cartans and A. annulipes) and their persistent attacks upon man, the mosquitoes (except in one case) were not attracted to healthy domestic rabbits exposed in the woods. Aëdes can have little, if any, part in the spread of myxomatosis. Observations made in the cool summer of 1954 were confirmed in the hot summer of 1955.

4. Engorged mosquitoes (apart from those which had just fed on the human collector) were never found, so precipitin tests could not be made. The source from which these woodland mosquitoes normally obtain their blood meals remains a mystery.

5. In the laboratory, the Aëdes were reluctant to feed on normal, healthy rabbits but fed readily (round the eyes and on the nose) on normal anaesthetized rabbits or comatose myxomatous rabbits. Biting experiments indicated that Aëdes may remain infective for up to 36 days after an infective blood meal.

6. Infected Aëdes were recovered from woods containing myxomatous rabbits, and tame rabbits infected by the bites of these mosquitoes developed myxomatous tumours on the nose. Although some Aëdes were thus feeding on wild myxomatous rabbits, the evidence that the mosquitoes did not feed on healthy rabbits indicates that Aëdes were of negligible importance as vectors of myxomatosis.
Solubility of Vi Antigen ofSalmonella Typhi
Authors: Chu David C. Y. , Hoyt Robert E. , Pickett M. J.
Published: May 2009

The observations reported here show that the T Vi antigen is effective in stimulating antibodies when it is attached to the cells. It is also clear that the Vi antigen is readily removed in aqueous solutions, but in such organic solvents as acetone, chloroform, ether, alcohol, carbon tetrachloride and benzene it is retained by the cell. In alcohol-water mixtures the Vi antigen is progressively more soluble in those solutions where the alcohol concentration is less than 70 %. However, its solubility in water is limited, and by making progressively heavier suspensions it was found that a point is reached at which Vi antigen is retained by the cell, the suspending solution apparently being saturated. Such an aqueous suspension is able to stimulate the production of Vi antibody.

The administration of dried organisms in peanut oil resulted in the production of antibodies against both O and Vi antigens. This was in contradistinction to the results obtained when mineral oil, mineral oil + saline, or peanut oil + saline were used: in these cases the O antibody titre was lower and Vi antibodies were produced in low titre or not at all. It seems clear that the presence of water in the vaccine has the effect of removing the antigenicity of the Vi hapten; water-free, vegetable-oil vaccine is suggested by these studies as an effective agent for immunizing against all of the antigens ofSalmonella typhi.The use of such a vaccine in producing active and passive immunity in animals is discussed in the paper which follows.
Susceptibility of the LLC-MK2 line of monkey kidney cells to human enteroviruses
Authors: Hambling M. H. , Davis Patricia M.
Published: May 2009

The relative susceptibility of the LLC-MK2 cell line and primary rhesus monkey kidney cultures to thirty-eight prototype strains of human enteroviruses is described; of these strains only ECHO types 16, 18, 21 and 23 failed to cause CPE in the continuous cell line. The efficiency of the two tissues for the isolation of enteroviruses from faecal extracts is compared. The results show that the LLC-MK2 cell line is very satisfactory for the isolation of Coxsackie B and polioviruses, but not so useful for the isolation of ECHO viruses. The identification of enteroviruses by neutralization tests in LLC-MK2 cells is successful.
Infection of sheep and monkeys with Langat virus: cross-protection against other viruses of the Russian spring-summer complex
Authors: O'Reilly K. J. , Smith C. E. Gordon , McMahon Dolores A. , Wilson A. L. , Robertson J. M.
Published: May 2009

1. The susceptibility of sheep to infection with Langat virus has been studied. No viraemia or symptoms were detected in sheep inoculated either subcutaneously or intracerebrally.

2. Only those sheep inoculated intracerebrally with 106·0–108·0 mouse IC LD 50 of virus developed significant quantities of neutralizing antibody.

3. Two-thirds of sheep vaccinated with varying doses of Langat virus withstood subcutaneous challenge of louping-ill virus followed by intracerebral starch. All the intracerebrally vaccinated sheep survived this form of challenge but no sheep, whether vaccinated subcutaneously or intracerebrally, withstood intracerebral challenge of louping ill.

4. In a field trial, three of ten hoggs vaccinated with Langat virus and exposed to natural louping ill infection at Camlarg and Dalcairnie died of the disease compared with all eight of the non-vaccinated hoggs. At Knockgray, there was no louping ill infection, but 93% of the hoggs from this hirsel developed louping ill antibody after transfer to Camlarg.

5. Monkeys infected intracerebrally, subcutaneously or orally with Langat virus showed a low titre viraemia without clinical symptoms or histological changes in the brain and developed high titres of antibody. Vaccinated monkeys challenged with either Central European tick-borne encephalitis or Kyasanur Forest disease viruses remained healthy compared with control monkeys which showed evidence of disease.
Wire mesh screening for the exclusion of houseflies
Authors: Busvine J. R.
Published: May 2009

Control of houseflies by modern insecticides is becoming unreliable owing to emergence of resistant strains, so that some older measures deserve reconsideration. Exclusion of mosquitoes by gauze has been studied experimentally but not, apparently, of houseflies.

Some simple tests show that a suitable gauze to exclude houseflies (and larger insects) would be 10 mesh 32 s.w.g. with an aperture 2·17 mm. square. This compares with a gauze recommended for excluding mosquitoes, 18 mesh and 32 s.w.g. with an aperture 1·16 mm. square.

The advantages of the wider gauze for flies are admission of more light and air and lower cost. Some simple experiments on the relative air resistance of mosquito ind fly gauze were made by a method involving retardation of a pendulum by a gauze circle. The results suggest that the obstruction to ventilation is roughly proportional to the percentage obstruction (as with light) which was 20 % for the fly gauze and 36 % with the mosquito gauze.
Combined enteric and cholera vaccination by the intradermal route
Authors: Noble J. E. , Fielding P.
Published: May 2009

The protection afforded by a combined enteric and cholera vaccine administered by the intradermal route, and demonstrated by active and passive mouse protection tests and agglutination titres, is excellent and equal to that given individually by the component TAB and cholera vaccines.

In order to reduce the number of injections required and the unpleasant reactions provoked it is suggested that combined enteric and cholera vaccine administered by the intradermal route is of value, where appropriate, for the vaccination of travellers, and for the rapid protection of non-immune persons in the event of natural disasters or mobilization.
Observations on photodynamic inactivation of vaccinia virus and its effect on immunogenicity
Authors: Turner G. S. , Kaplan C.
Published: May 2009

Photoinactivation of vaccinia virus sensitized by methylene blue had parameters similar to those observed with other viruses. Thus inactivation proceeded exponentially to completion, was irreversible, independent of temperature and the intensity of illumination. Inactivation was dependent on the dose of illumination and the concentrations of both methylene blue and hydrogen ions. The effects of pH appeared to be primarily concerned with the tenacity of dye-virus binding. Inactivation was inhibited by small amounts of nucleic acid but not by their bases or pentoses. Inactivation was only affected by the presence of extraneous protein in relatively high concentration: it was not affected by the enzymes catalase or peroxidase. Attempts to obtain direct chemical evidence of the participation of viral nucleic acid in photoinactivation were unsuccessful.

Recombination experiments strongly indicated the involvement of viral protein in photoinactivation. Immunogenicity was not impaired since good responses of neutralizing antibody were obtained in rabbits immunized with vaccines photoinactivated over a wide range of exposure times.
Attenuation of virulence inVibrio cholerae
Authors: Bhaskaran K. , Sinha V. B.
Published: May 2009

This paper describes the study of a mutant ofVibrio choleraewhich is shown to be attenuated by its avirulence to mouse, rabbit and chick embryo. This mutant character is stable, and the avirulence of this strain probably results from its inability to multiply actively in the tissues of the infected animals. The need for the study of such attenuated strains as live vaccines in man is discussed, and certain aspects of immunity to cholera are reviewed.
The progression of herpes simplex virus to the central nervous system of the mouse
Authors: Wildy Peter
Published: May 2009

1. The strain HFEM of herpes simplex virus is highly virulent for the 5-week-old mouse when inoculated intracerebrally; the LD50 and the ID50 both being close to the egg infectious unit. It is also virulent when given intraspinally.

2. When inoculated peripherally it seldom causes nervous symptoms in the normal mouse but regularly does so if inoculated into skin which has previously been given a subcutaneous injection of 10% sodium chloride.

3. After intradermal inoculation of pretreated mice with strain HFEM, the paralysis is preceded by the appearance of infective virus in the blood, the sciatic nerve and the central nervous system. Invasion of the central nervous system is prevented by interruption of the local peripheral nerve.

4. There is no evidence that virus enters the central nervous system by way of the lymphatics or by direct extension through the tissues.

5. After intravenous inoculation virus does not invade the central nervous system unless (a) massive inocula are used or (b) the brain is traumatized by injecting sterile saline. After peripheral inoculation insufficient virus to infect even traumatized brain seems to circulate in the cerebral vessels. Paralysis and invasion of the central nervous system are not prevented by circulating neutralizing antibody given 18 hours after inoculation.

It therefore appears that invasion of the central nervous system takes place only by way of the peripheral nerve.
A comparison of RK13, vervet monkey kidney and patas monkey kidney cell cultures for the isolation of rubella virus
Authors: Best Jennifer M. , Banatvala J. E.
Published: May 2009

RK 13 and primary PMK and VMK cell cultures were compared for the isolation of RV by means of the simultaneous inoculation of original specimens and early passage material. RK 13 was found to be the most sensitive and reliable and provided a result for both isolation and neutralization in the shortest time. As the interpretation of CPE and the propagation of these cultures is sometimes difficult, the simultaneous use of a second system in which RV is easy to identify, e.g. VMK or PMK cell cultures, is recommended. Both PMK cell cultures and LLC-RK1 were suitable for isolating RV from clinical specimens. Preliminary studies with LLC-RK 1 indicate that it may provide an even more sensitive alternative to RK 13, but further studies employing clinical material require to be carried out before firm conclusions can be reached.
Mercury resistance and tetracycline resistance inStaphylococcus aureus
Authors: Williams R. Fraser
Published: May 2009

Minimum inhibitory concentrations of tetracycline to 256 tetracycline-resistant strains ofStaphylococcus aureuswere determined. M.I.C.'s tetracycline were appreciably higher among mercury resistant than among mercury sensitive strains.

Mercury resistant strains representing various M.I.C.'s tetracycline grew significantly better in peptone water containing a therapeutic concentration of tetracycline than mercury sensitive strains representing the same range of resistance. The experiment was repeated after both groups had been adapted—or ‘trained’—to grow on agar containing tetracycline, 100µg./ml. The mercury sensitive strains now grew better than the mercury resistant group.

The significance of these findings is discussed. It is concluded that tetracycline resistance is more stable and efficient in mercury resistant strains, and that it is probably genetic in origin—the result of mutation and selection. Tetracycline resistance in mercury sensitive strains is possibly the result of ‘training’.

The associations and significance of both mercury resistance and tetracycline resistance inStaphylococcus aureusare discussed.
The incidence ofHerpesvirus hominisantibody in the population
Authors: Smith Isabel W. , Peutherer J. F. , MacCallum F. O.
Published: May 2009

Sera from 1029 individuals, 864 from Edinburgh and 165 from Oxford, have been examined for the presence of antibodies toHerpesvirus hominis. The results of the smaller Oxford survey did not reveal a higher incidence of antibody where direct comparison was possible with those from Edinburgh.

The incidence of both complement-fixing and neutralizing antibodies in the sera from 710 people in Edinburgh with ages varying from 1 month to 92 years was compared with the more complete of the earlier surveys, and in particular with that of Holzelet al.(1953) in Manchester, England. This comparison revealed a lower incidence of antibody in people under 25 in Edinburgh in 1965.

Results obtained with sera from medical students in Oxford and Edinburgh and from nurses in Edinburgh were in agreement with those of previous surveys. The low incidence of antibody in these young people emphasized the possible occupational risk of infection from patients and that primary herpetic infection might be encountered more frequently than before in teenagers and young adults.
The occurrence of neutralizing and complement fixing antibodies in rubella
Authors: Field Anne M.
Published: May 2009

Neutralization and complement-fixation tests to detect rubella antibody are described. Results of such tests show that between 80 and 95% of adults in England and Wales have neutralizing antibody. The presence of complement-fixing antibody indicates recent infection with rubella virus.

Results are presented showing the development of neutralizing and complement-fixing antibody after rubella.

Antibody tests on children with congenital rubella and their mothers are detailed. It is noted that higher neutralizing antibody titres are found in this group than in the general population.
Immunization of man with salmonella vaccine and tetanus-diphtheria vaccine. Dose-response relationship, secondary response, and competition of antigens
Authors: Clasener H. A. L.
Published: May 2009

Immunization of men with various amounts of salmonella antigens gave a linear relationship between the logarithm of the dose and the logarithm of the titres of the antibodies produced. No secondary response was observed for any of the doses used. These doses of salmonella vaccine did not interfere with or stimulate simultaneous primary or secondary vaccination with tetanus and diphtheria vaccine.
An assessment of oil adjuvant and aqueous influenza vaccines: I. Reactions to the vaccines
Authors: Forsyth J. R. L.
Published: May 2009

Trials of aqueous and oil adjuvant vaccines in young adult volunteers showed that severe local reactions were rare. However, the incidence of minor symptoms was too high for a vaccine which requires to be administered repeatedly. In contradistinction to some reports, systemic and allergic reactions did not constitute a problem.
Carriage ofStaphylococcus aureusin random samples of a normal population
Authors: Noble W. C. , Valkenburg H. A. , Wolters Caroline H. L.
Published: May 2009

Nose, throat and finger carriage ofStaphylococcus aureuswas investigated in a series of random samples from a normal European population.

No evidence for a seasonal trend in carriage was found but the intersample variation between successive random samples was obtained. The mean nasal carrier rate was 29 % with a standard deviation of 7 %.

No association was found between nasal or throat carriage of staphylococci and stay in hospital or antibiotic therapy but respondents with penicillin-resistant staphylococci in the nose had skin infections more frequently than those with penicillin-sensitive strains.

Evidence was obtained for a family, perhaps genetic, ‘predisposition’ to carry staphylococci in the nose.
The virulence of T-mycoplasmas, isolated from various animal species, assayed by intramammary inoculation in cattle
Authors: Howard C. J. , Gourlay R. N. , Brownlie J.
Published: May 2009

The virulence of T-mycoplasmas for cattle was tested by examining their ability to produce mastitis in cows. It was found that both virulent and avirulent strains of T-mycoplasmas can be isolated from cattle. All of four strains from pneumonic calf lungs and a strain from a case of bovine kerato-conjunctivitis caused mastitis but only two of four strains isolated from the urogenital tract of cows were virulent. None of the human, simian or canine T-mycoplasmas examined were able to cause mastitis in cattle. However, a bovine strain was found to be capable of causing mastitis in goats. Virulent and avirulent strains from the same and different species contain common antigens detected by the metabolic inhibition test. Pathogenicity could not be shown to be characteristic of any particular serotype. The possibility is raised of some species barrier being responsible for the inability of non-bovine strains to infect cattle.
Interactions of TRIC agents with macrophages and BHK-21 cells observed by electron microscopy
Authors: Lawn A. M. , Blyth W. A. , Taverne Janice
Published: May 2009

TRIC agents do not multiply in mouse peritoneal macrophages in culture but have a toxic effect on them, whereas they multiply readily in BHK-21 cells. Sections of macrophages and of BHK-21 cells fixed during the first 90 min after inoculation were examined by electron microscopy. Macrophages ingested all forms of the organism, which were eventually degraded in lysosomes. However, elementary bodies were distinguished from other TRIC particles by the delay in their transfer to lysosomes. BHK-21 cells ingested elementary bodies selectively, and in these cells the organisms were neither found in lysosomes nor degraded. Instead they showed morphological changes that probably represented an early stage of development.
A bacteriological evaluation of laminar-flow systems for orthopaedic surgery
Authors: Whyte W. , Shaw B. H. , Barnes R.
Published: May 2009

An evaluation has been undertaken of the efficiency of laminar-flow ventilation in operating-rooms in which conventional operating-room clothing was used. It has been demonstrated that velocities in the region of 0·3–0·4 m/sec. will give maximum returns for effort in both down-flow and cross-flow systems. At this velocity the laminar-flow system, in terms of airborne bacteria measured at the would site, was about 11 times more effients using horizontal air-flow and 35–90 times more efficient using vertical air-flow than a plenum-ventilated operating room.
Serum antibody response in acute brucellosis
Authors: Farrell I. D. , Robertson L. , Hinchliffe P. M.
Published: May 2009

The serum antibody titres in 62 cases of acute brucellosis are presented. The antibody persisting after infection and the appearance of non-agglutinating antihuman globulin titres were investigated. The criteria for the serological diagnosis of acute and chronic brucellosis are discussed.
Examination of slurry from cattle for pathogenic bacteria
Authors: Jones P. W. , Matthews P. R. J.
Published: May 2009

One hundred and eighty-seven samples of slurry from cattle were examined for the presence of salmonellas, pathogenic leptospires and brucellas. Small numbers of salmonellas, generally less than 1/g., were isolated from 20 samples (11%). These were S. dublin (12), S. typhimurium (4), S. indiana (1), S. bredeney (1), S. cerro (1) and S. unnamed 4,12: d:—(1).

Leptospires were isolated from 56 samples (30%) but none was pathogenic for hamsters. No brucellas were isolated. The results of this survey are discussed in relation to the epidemiology of salmonellosis.
Laboratory evaluation of difenacoum as a rodenticide
Authors: Hadler M. R. , Redfern R. , Rowe F. P.
Published: May 2009

The efficacy of difenacoum as a new anticoagulant rodenticide was evaluated by blood coagulation studies and laboratory feeding tests using warfarin-resistant and non-resistant common rats (Rattus norvegicus), ship rats (R. rattus) and house mice (Mus musculus). Prothrombin assays indicated that the compound had as marked an activity with warfarin-resistant common rats as coumatetralyl had with non-resistant animals. Feeding tests confirmed that 0.005% would be a near-optimal concentration for field use, although there was some evidence of unpalatability.

Results with ship rats and house mice were less favourable. Trials with enclosed colonies of warfarin-resistant mice confirmed the laboratory finding that although difenacoum was more effective than all other currently used anticoagulants, it was unlikely to give complete control.

It is concluded that difenacoum is a valuable new rodenticide, especially for controlling warfarin-resistant common rats.
The faecal flora of children in the United Kingdom
Authors: Ellis-Pegler R. B. , Crabtree C. , Lambert H. P.
Published: May 2009

The faecal flora of 55 children (aged 8 days to 8 years) and 16 adults was determined. All the children were artificially fed from birth. The faecal flora of the youngest age group was generally less complex and less predictable than that of adults. Some bacterial groups commonly found in adult stools, for example bacilli, lactobacilli and yeasts, were rarely found in the youngest infants. Most of the changes towards the adult pattern took place between 4 and 12 months. The faecal flora of children aged 1–4 years generally resembled that of adults, although lactobacilli were still infrequently isolated.
The effect of feeding diets containing permitted antibiotics on the faecal excretion of Salmonella typhimurium by experimentally infected chickens
Authors: Smith H. Williams , Tucker J. F.
Published: May 2009

Groups of 45 chickens were fed continuously on diets containing 10 or 100mg./kg. of different ‘growth-promoting’ antibiotics and infected orally with a nalidixic acid-resistant mutant of Salmonella typhimurium. The amount of S. typhimurium organisms excreted in their faeces was estimated by culturing them at weekly intervals and in a standard manner on plates of brilliant green agar containing sodium nalidixate, both direct and after enrichment in selenite broth.

All of four groups fed diets containing 100 mg./kg. of nitrovin in three different experiments excreted much larger amounts of S. typhimurium than did groups fed antibiotic-free diets. In some, but not all, experiments, larger amounts were also excreted by groups fed diets containing 10 mg./kg. of nitrovin or 10 or 100 mg./kg. of flavomycin or tylosin. Feeding diets containing 10 or 100 mg./kg. of virginiamycin or bacitracin either did not influence or slightly ncreased the amount of S. typhimurium excreted.

Two groups fed continuously on diets containing 100 or 500 mg./kg. of sulphaquinoxaline for 44 days excreted smaller amounts of the S. typhimurium organisms than did groups fed antibiotic-free diets; no sulphonamide-resistant organisms of the S. typhimurium strain were isolated from the faeces.
Salmonella serotypes, Salmonella typhi phage types, and anti-microbial resistance at the University Hospital of the West Indies, Jamaica
Authors: French G. L. , King S. D. , St Louis P.
Published: May 2009

Bacteriologically proved cases of salmonellosis presenting at the University Hospital have increased nearly threefold since 1957. The most striking change has been a considerable increase in the incidence of Salmonella heidelberg and Salmonella derby in the last 5 years, probably resulting from hospital acquired infection.

About 80 cases of typhoid fever are reported each year in Jamaica. There has been little change in the prevalence of different phage types of Salmonella typhi since 1961. Paratyphoid fever is rare.

Standardized antimicrobial disk-sensitivity testing was performed on selected surviving salmonella strains since 1964. S. typhi has remained fully sensitive to all the agents tested except streptomycin. Other salmonellas, however have shown a significant increase in antimicrobial resistance since 1970. Most of this increase was due to multiple resistance in S. heidelberg and S. derby, and the survival and dissemination of these strains in the hospital environment may be related to antibiotic usage.
The immunization of mice and calves with gal E mutants ofSalmonella typhimurium
Authors: Wray C. , Sojka W. J. , Morris J. A. , Morgan W. J. Brinley
Published: May 2009

A galactose epimeraseless (gal E) mutant ofSalmonella typhimuriumwas investigated in mice and calves for its suitability as a live vaccine. In mice, a very highly significant difference in the mortality rates was observed when vaccinated and non-vaccinated animals were challenged with virulent strains ofS. typhimuriumandS. dublin.

In calves, doses of 106and above of gal E mutant injected subcutaneously provided highly significant protection both in terms of mortality and prevalence of symptoms when calves were challenged orally withS. typhimurium.However, there appeared to be a relation between the vaccine and the presence of renal lesions and before gal E mutants can be recommended, further work is necessary to determine the pathogenesis of these lesions.
Water beds – a potential source ofPseudomonas aeruginosa
Authors: Elhag K. M. , Baird Rosamund M. , Shaw Elizabeth J.
Published: May 2009

Water beds in use in this hospital were found to be contaminated withPseudomonas aeruginosa.The addition of sodium hypochlorite, giving a final concentration of 200 parts/106available chlorine, was found to be effective in preventing microbial contamination over a 6-month study period.
The use of single-radial-haemolysis for rubella antibody studies
Authors: Clarke Mairin , Boustred Janet , Seagroatt Valerie , Schild G. C.
Published: May 2009

The use of a single-radial-haemolysis technique for the detection of antibody to rubella virus is described. The single-radial-haemolysis test was compared with the standard HI methods for the detection of antibody to rubella virus. A close correlation between the two methods was observed in a survey of over two thousand serum samples and the study indicated that single-radial-haemolysis was highly satisfactory as an assay method for IgG antibodies to rubella virus. It was found that the immuno-globulins active in SRH tests sedimented in the 7S range in sucrose rate gradients and were presumably immunoglobulins of the IgG class, but 19S iinmunoglobulins did not produce haemolysis.
The metabolic inhibition test for mycoplasmas based on phosphatase production
Authors: Hill Auriol C.
Published: May 2009

A metabolic inhibition test based upon phosphatase production is described. This is of value for thoseMycoplasmaspecies which produce phosphatase but which cannot be examined by the previously published metabolic inhibition techniques.
Field trials of WBA 8119 (PP 581, brodifacoum) against warfarin-resistant infestations of Rattus norvegicus
Authors: Rennison B. D. , Dubock A. C.
Published: May 2009

Baiting with medium oatmeal or soaked wheat containing 0.002, 0.001 or 0.0005% brodifacoum completely controlled infestations of warfarin-resistant rats on farms when the poisoned baits were maintained until rats ceased to feed on them. The concentration of brodifacoum did not affect the duration of these treatments which lasted from 11 to 25 days.

Poison baiting with 0.002% brodifacoum for only 1, 4 and 7 days achieved, respectively, only about 41, 51 and 68% control of similar farm infestations, and so emphasized the need to continue baiting for longer periods.
The hygienic quality of vegetables grown in or imported into the Netherlands: a tentative survey
Authors: Tamminga S. K. , Beumer R. R. , Kampelmacher E. H.
Published: May 2009

Samples of 61 home grown and 199 imported vegetables of different varieties were examined forEscherichia coli, faecal streptococci and, whenE. coliwas present, for salmonellas. Eleven per cent of samples contained > 104E. coliper 100 g, and 14% > 106faecal streptococci per 100 g. Salmonellas were isolated from 23 out of 103 samples examined.

Salmonellas were isolated from 8% of 76 samples withE. coli<104/100 g, but from 63% of 27 samples withE. coliexceeding 104/100 g; from 6% of 65 samples containing < 106faecal streptococci/100 g but from 51% of 37 samples containing more than 106/100 g.

S. typhiwas isolated from one sample of vegetables imported from the tropics. To our knowledge this is the first isolation ofS. typhifrom food in the Netherlands. Products from tropical countries were found to present the highest level of contamination. The hygienic quality of Dutch products is sometimes inferior to that of similar imported products, although the different seasons of sampling may have influenced the result. For the prevention of risk to the consumer of vegetables, good kitchen hygiene would appear to be the most important factor.
Antibody responses to vaccination with WRL 105 strain live influenza vaccine in previously vaccinated and unvaccinated volunteers
Authors: Evans A. E. J. , Simmons R. L. L. , Ferris R. D. , Hasell S. K. , Letley E. , Freestone D. S.
Published: May 2009

Intranasal vaccination with a single 0·5 ml dose of 107.0EID 50 WRL 105 strain live influenza vaccine elicited four-fold or greater increases in circulating homotypic haemagglutinating inhibiting (HAT) antibody in 60 (64·5 %) of 93 volunteers, or in 58 (74·4%) of 78 volunteers with HAI antibody titres before vaccination of ≤ 1/20. In comparison, in a group of volunteers vaccinated 9 months previously re-vaccination elicited antibody responses in only 4 (6·9 %) of 58 volunteers, or in 3 (14·3%) of 21 volunteers with antibody titres before vaccination of ≤ 1/20.

Titres of vaccine-induced antibody and antibody resulting from earlier natural infection appeared to fall slowly and at equivalent rates over a 9 month period.
The virulence of trimethoprim-resistant thymine-requiring strains ofSalmonella
Authors: Smith H. Williams , Tucker J. F.
Published: May 2009

A thymine-requiring (thy−), trimethoprim-resistant (tmpr) mutant isolated from the faeces of chickens experimentally infected withSalmonella typhimuriumand treated with a mixture of trimethoprim and sulphadiazine was less virulent for chickens than the parent strain and athy+tmpsrevertant preparedin vitrofrom the mutant. The difference in chicken-virulence was more noticeable when the strains were administered orally than when they were administered subcutaneously. Alltmprmutants preparedin vitrofrom four other salmonella strains were alsothy−; those tested were less virulent for chickens and mice than their parent strains. After oral infection,thy−salmonella organisms were found much less commonly in the alimentary tract of chickens then werethy+organisms. This was especially so in the caeca, the principal site of colonization of both thethy+andthy−organisms. Relatively high concentrations of thymine or related compounds were found in the contents of all regions of the alimentary tract of chickens except the caeca; the caeca usually contained low or undetectable concentrations.

Thethy−salmonella strains would not grow on one brand of brilliant green agar because of its deficiency in thymine; their colonial appearance on other kinds of media used for isolating salmonellae from clinical material was often ‘un-salmonella-like’.
A major gene controlling warfarin-resistance in the house mouse
Authors: Wallace Margaret E. , MacSwiney Felicity J.
Published: May 2009

The spread of a 'cream' mutant in a wild population of house mice is reported. The hypothesis that the gene responsible for the colour, extreme chinchilla, ce, has spread because of linkage with a major gene for warfarin-resistance, is tested by a linkage backcross.

The results prove that a major gene does exist, that it is very closely linked with frizzy, fr, in chromosome 7, which in turn is linked with ce, that it is fully dominant in females at 4 months of age, and that its partial dominance in males is under the control of modifiers.

The symbol War is proposed for the gene. Its position in chromosome 7 is analagous with the position of the resistant gene, Rw2, in the rat in the analagous chromosome.

The adaptive significance of this finding is discussed, as also are reports of certain other mutants in wild populations of mice.
Seroepidemiological study of HBV infections in Athens, Greece
Authors: Papaevangelou G. , Kyriakidou A. , Vissoulis C. , Trichopoulos D.
Published: May 2009

A seroepidemiological survey of a sample – roughly representative by age and sex – of 2744 persons of the Greater Athens area revealed that hepatitis B virus (HBV) infections are highly endemic in Greece. Hepatitis B surface antigen (HBsAg) was detected in 72 (2·6 %) of them. The subtype was identified in 70 of the 72 carriers, and 69 were ay; the other was ad. Determinant w was present in all 61 that were capable of being typed further, and a23y(w) was twice as common as a11y(w). Antibody to HBsAg (anti-HBs) was found in 514 (18·7%) persons. The prevalence of the HBsAg rose rapidly with age, reaching peak values (5·3%) at 20–29 years, while anti-HBs reached its highest value (42·1%) in older age groups (50–59 years). The frequency of HBsAg was significantly higher in males (3·4%) than in females (1·5%). The percentage of infected persons who become chronic HBsAg carriers (12·3%) was found higher than in other developed populations. It was also found higher in children (25%) than in adults (5·5%) and in males (14·6%) than in females (8·1%). These data indicate that HBV infection in early life is a major risk factor in the development of HBsAg carriers and support the hypothesis that males are more likely to become HBsAg carriers than females.