bluuebunny/crossref_metadata_2025_split huggingface dataset:
Observations on the carrier state and related antibody titres during an outbreak of foot-and-mouth disease
Authors: Hedger R. S. 
Published: May 2009

SummaryAn outbreak of foot-and-mouth disease in a partially immune population of cattle in Botswana is described. The results show that when cattle immunized by vaccination were presented with natural field challenge of FMD, many animals with immunity sufficient to protect them against clinical disease were, however, susceptible to pharyngeal infection and subsequently became virus carriers. The proportion of animals becoming carriers appeared to vary with the degree of severity of the challenge.Vaccination before exposure to virus appeared to have little effect on the duration of the carrier state. No evidence was obtained of the spread of carrier virus to immune herds following the outbreak.Antibody titres during the outbreak were higher in the clinically infected animals than in the carrier animals and the uninfected animals. Evidence suggested that natural challenge boosted the titres of immune animals. After the outbreak, however, it was not possible to distinguish by their antibody titres between the carrier animal and the virus-negative animal.Antigenic studies on the strains of virus isolated are described.
Degradation of influenza virus by non-ionic detergent
Authors: Corbel M. J. , Rondle C. J. M. , Bird R. G. 
Published: May 2009

SummaryPreparations of influenza virus A0 PR 8/34 and A 2 Malaysia/68 have been studied in the electron microscope. They were similar in appearance to preparations made by others. Each preparation was degraded by Triton N 101. The process of degradation appeared to be different from that observed using ether and, by inference, a number of other agents.
Direct complement fixation test with avian infectious bronchitis virus in chickens
Authors: Uppal P. K. 
Published: May 2009

SUMMARYThe direct complement fixation test was performed to follow the antibody response in chickens infected with avian infectious bronchitis virus. Concentrated allantoic fluid (4 units) was used as an antigen and allowed to react with serially diluted antiserum in the presence of two complete units of guinea-pig complement for 3 hr. at 4°C. and ½ hr. at 37°C. before the addition of sensitized cells. Serum was unheated and used either fresh or within one month of storage at −30°C. Individual birds showed a rise and fall of complement-fixing antibody both after primary and secondary inoculations. The complement-fixing antibody was detected as early as the seventh day after primary inoculation. The highest complement fixation titre (1/32 to 1/64) was recorded from 14 to 21 days after inoculation with a subsequent gradual decline.The results of the direct complement fixation tests have been correlated with the serum neutralization test. The neutralizing antibodies usually appeared by the 14th day but were not detected at a significant titre until the 21st day after primary inoculation. Serum neutralizing antibodies were still present at high titres even after 7 weeks of infection but the complement-fixing antibodies had disappeared by that time.
Vaccination against rubella and measles: quantitative investigations of different policies
Authors: Anderson R. M. , May R. M. 
Published: May 2009

SUMMARYThis paper uses relatively simple and deterministic mathematical models to examine the impact that different immunization policies have on the age-specific incidence of rubella and measles. Following earlier work by Knox (1980) and others, we show that immunization programmes can, under some circumstances, increase the total number of cases among older age groups; the implications for the overall incidence of measles encephalitis and of congenital rubella syndrome are examined, paying attention both to the eventual equilibrium and to the short-term effect in the first few decades after immunization is initiated. Throughout, we use data (from the U.K., and U.S.A. and other countries) both in the estimation of the epidemiological parameters in our models, and in comparison between theoretical predictions and observed facts. The conclusions defy brief summary and are set out at the end of the paper.
Otitis externa byPseudomonas aeruginosaassociated with whirlpools
Authors: Havelaar A. H. , Bosman M. , Borst J. 
Published: May 2009

SUMMARYOver a period of about 1 year, otitis externa occurred in at least 300 visitors to a recreational park. The infections were associated with the presence ofPseudomonas aeruginosain insufficiently chlorinated whirlpools.
The Spread of Bacterial Infection. Some Characteristics of the Pre-epidemic Phase
Authors: Topley W. W. C. 
Published: May 2009

1. During the pre-epidemic stage of the spread of bacterial infection among mice, single deaths, or small groups of deaths, due to the specific infection being studied, are found to occur at considerable intervals before the rise of the main epidemic wave, and to afford a warning that such a wave is at hand.2. In many cases there may be observed, during the same period, an increase in the daily mortality from all causes.I should wish to express my thanks to Dr Major Greenwood for the interest he has shown in this investigation, and for much useful information with regard to epidemiological records. I am again greatly mdebted to my co-workers, Dr H. B. Weir and Dr G. S. Wilson, for their assistance in these experiments.
Studies of the Action of Electrolytes on Bacteria. Part II. The Influence of the Trivalent Positive Salts on the Rate of Migration of Bacteria in an Electric Field, and their Effect on Growth and Virulence of Pathogenic Organisms.
Authors: Shearer C. 
Published: May 2009

1. In the foregoing experiments evidence is adduced to show that bacteria in spleen broth or neutral Ringer's solution carry a negative charge and move to the anode in an electric field. The addition of a slight trace of a positive trivalent ion such as La or Ce or Yb to the solutions containing the bacteria immediately lessens or neutralises this negative charge, and if the concerntration of these ions is further increased completely abolishes it, and the bacteria undergo flocculation or agglutination. Living bacteria seem much more sensitive to the action of these ions than non-living colloidal particles. The addition of negative trivalent ions to bacterial cultures is without any effect on their movement in an electric field; the negative charge on the bacteria is not increased.2. Some inconclusive evidence has been brought forward in support of Girard and Audubert's work regarding the influence of the double electric layer of the bacterial cell wall in controlling their biological properties.
Studies in bacterial Variability. The Experimental Production of a Mucoid form of B. paratyphosus B
Authors: Walke E. W. Ainley 
Published: May 2009

1. The experimental derivation of a mucoid form of B. paratyphosus B is described.2. This form, though at one stage non-motile, agreed closely with the “capsulated mucoid forms” of paratyphoid B, isolated by W. Fletcher from two chronic “carrier” cases.3. The mucoid paratyphoid B was highly dys-agglutinable, and it would not on serological examination be identified as a paratyphoid B.4. Its colonies were also entirely unlike colonies of paratyphoid B, being large, slimy, and usually dome-shaped, though at other stages of their metamorphosis they presented either an umbilication, or a nipple-like elevation in the centre.5. The mucoid bacillus possessed the distinctive sugar reactions of paratyphoid B.6. On suitable manipulation it reverted to the ordinary form.
The Schick Dose of Diphtheria Toxin as a Secondary Stimulus
Authors: Glenney A. T. , Allien K. 
Published: May 2009

The injection of the small amount of diphtheria toxin used in the Schick test may act as a secondary stimulus.A Schick test may therefore cause a great and rapid increase in the immunity of the animals tested.Examples are quoted of six rabbits and twelve guinea-pigs in Tables II to VII.2. A fraction of a Schick dose may act as a secondary stimulus. Rabbit G 23 quoted in Table IV, injected with 1/10 of a Schick dose, showed an immunity response, the antitoxic content of its blood rising from 1/50 to nearly 1/10 unit per c.c. in six days.3. The action of a Schick dose as a secondary stimulus may cause an animal to give a negative reaction when tested seven days or more after the first positive reaction.This is illustrated by rabbits G 7 in Table III, G 31 in Table II, G 32 and G 34 in Table V and four guinea-pigs in Table VI.4. The antigenic value of a Schick dose of toxin as a secondary stimulus may be as high as that of a reasonable dose of a toxin-antitoxin mixture suitable for human immunisation. Examples are given comparing the results of the injection of a Schick dose of toxin and of a toxin-antitoxin mixture in the same rabbit in Table III, in different rabbits, G 20 and G 22 in Table IV and reference is made to the companion rabbits to those quoted in Table V.5. The antigenic value of a Schick dose as a secondary stimulus can be demonstrated:A. In animals which have not produced a detectable quantity of antitoxin (that is less than 1/2000 of a unit per c.c.) as the result of a primary stimulus.See both rabbits in Table II, rabbit G 20 in Table IV, both rabbits in Table V, and guinea-pig FF 19. v in Table VII. The four guinea-pigs in Table VI probably come under the same heading.B. In animals whose actively produced antitoxin has fallen below a de tectable level.See rabbit G 7 in Table III.(These results add further confirmation to the phenomenon reported in the paper “Active immunity to diphtheria in the absence of detectable antitoxin” (Glenny and Allen, 1922).6. A Schick dose of toxin which gives a positive reaction may, by acting as a secondary stimulus, produce a rapid increase in the antitoxic value of animals already containing some actively produced antitoxin.See guinea-pig LL 17. vi in Table VII.7. A Schick dose of toxin which causes no reaction may, by acting as a secondary stimulus, produce a rapid increase in the antitoxic value of animals already containing some actively produced antitoxin.See guinea-pigs in Table VII.8. A Schick dose of toxin may fail as a secondary stimulus if the antitoxic content at the time of injection is comparatively high.See rabbit G 21 in Table IV.
Behaviour of Diphtheria Bacilli in Acidified Media, especially with reference to Virulence Tests
Authors: Hall I. Walker 
Published: May 2009

1. The growth of diphtheria bacilli in suger-free pure casein digest broth may be accelerated by the addition of dilute nitric, acetic and lactic acids, and delayed by certain monobasic fatty acids.2. The limiting acid zone for toxic and non-toxic varieties is unaffected by initial dilute acidifications by several acids, but incresaed by the addition of citric acid.3. The time periods and intensity of the reaction changes produced by diphtheria bacilli growing in a sugar-free casein digest medium are altered by the addition of certain acids. Toxic strains produce earlier and more progressive alkalinity when dilute acetic or nitric acid is included in the medium: and later and lessened alkalinity in the presence of butyric, formic, and propionic acids. Certain other typical acids do not exert any obvious action. Non-toxic strains are less affected by the selected acids, although butyric acid generally retards reaction changes.4. The time required for virulence testing is decreased, and the potency of the bacillus under examination is more evident when 1/200 η acetic or nitric acid is added to the culture medium. Acidified casein digest plus peptone broth yields practically the same results as acidified fermented veal peptone infusion. The acidification does not affect the metabolism of non-toxic strains.5. The disadvantages of unfermented meat infusions and the ascribed harmful effects of the fermentation products in fermented meat broths, may perhaps be avoided by the substitution of casein digest peptone medium. The advantages of the starting action of the glucose may be retained by adding acetic or nitric acid to the casein digest.6. Individual strains of diphtheria bacilli differ considerably in their capacity of altering the reaction of culture media, and in their toxic potency. It does not seem permissible to apply to newly isolated organisms all the published results obtained from cultures that have been repeatedly subcultured and established as toxin producers in nutrient bouillon. As a presumptive test in the virulence testing of bacilli just transferred from human tissues to artificial culture media the tendency of non-toxic strains to produce early formation of alkali in adequately buffered and adjusted unfermented veal broth may be thought worthy of extended trial.
OnBacillus coliInfections of the Urinary Tract especially in relation to Haemolytic Organisms
Authors: Dudgeon Leonard S. , Wordley Eric , Bawtree Frank 
Published: May 2009

(1) Two types of B. coli are met with in urinary infections-haemolytic and non-haemolytic. Haemolytic colon bacilli are much commoner in infections in the male (72 per cent.) and non-haemolytic in the female (70 percent).(2) It was very uncommon to obtain both these types of colon bacilli associated in any particular case, or for a haemolytic infection to be followed by a non-haemolytic, or vice versa.(3) No evidence was obtained of direct relationship between the urinary haemolytic colon bacilli and those of the intestinal tract.(4) The haemolytic urinary colon bacilli were readily grouped by appropriate colon anti-sera, but this result was much less common with the non-haemolytic strains.(5) Culture media, in our experience, were of little value in the grouping of colon bacilli.(6) A haemolytic colon bacillus has not been cultivated by us from the blood stream in the human subject.(7) Two cases of acute infection were met with, caused by strongly haemolytic, but atypical, colon bacilli.(8) The blood sera from “normal” cases and from coli infections were tested for the presence of coli agglutinins. Several coli antigens were employed. A very much higher percentage of positive findings were obtained with coli cases.(9) Living colon bacilli, haemolytic and non-haemolytic, can be inoculated into rabbits in small or massive doses without serious ill-effect-in fact these animals have a remarkable tolerance for these organisms. No marked anaemia was produced by the injection of living or dead bacilli or filtered broth cultures. Agglutinins and precipitins were rapidly formed with the haemolytic strains.(10) Eenal infections in rabbits were not obtained by the injection intravenously of various strains of urinary and faecal colon bacilli.(11) Saturation agglutinin experiments showed in the majority of instances that colon anti-sera, made from non-haemolytic strains, are not desaturated by non-haemolytic colon bacilli other than autogenous strains, while with the urinary haemolytic colon anti-sera and haemolytic colon bacilli a much wider range of action is obtained.(12) Precipitins and complement fixation reactions were readily obtained with coli rabbit anti-sera and filtered beef broth coli cultures.(13) The action of No. 220 soluble mercurochrome was investigated in the treatment of coli infections of the urinary tract. This substance was found to be of definite therapeutic value, especially when employed in conjunction with vaccine therapy.
The Fumigation of Ships with Liston's Cyanide Fumigator
Authors: Liston W. Glen , Goré S. N. 
Published: May 2009

(1) These experiments prove that the fumigator is safer to use than the dumping fixture, because high concentrations of the poison gas are avoided, so that dangerous pockets are not developed.(2) The poison gas is more evenly distributed over the different parts of the section of the ship under treatment.(3) High concentrations, however, can be developed^ at will in any part which requires special attention.(4) The maximum concentrations of the poison gas were obtained in every part of the section in a shorter time, when the fumigator was used, than when the dumping fixture was employed.(5) The artificial ventilation caused by the fan, which is capable of blowing into the section 500 to 1000 cubic feet of fresh air per minute, according to the speed of the motor, materially assists the rapid clearing of the poison gas from the ship, after it has accomplished its work. It is thus possible to complete the fumigation and ventilation of a ship in 3 hours using the cyanide fumigator, while more than 4 hours are required for the dumping fixture.(6) Even more important is the fact that smaller quantities of cyanide can be used with greater efficiency in the fumigator, than larger quantities, with less efficiency in the dumping fixture.(7) The general conclusion is arrived at, that, from the point of view of efficiency, safety and economy, the fumigator is superior to the dumping fixture. Creel has shown that, in respect to the time required for completing the fumigation, and in respect to the thoroughness of the process, both in killing rats and insects, the dumping fixture is superior to the Clayton gas machine. It follows, therefore, that the cyanide fumigator is very much superior in these respects to the Clayton gas machine.
Some Notes on Pneumonia Statistics in Glasgow with Special Reference to Children under Five Years of Age
Authors: Smith Charles M. 
Published: May 2009

1. Notification and hospitalisation have had no apparent effect on the death rate from pneumonia in Glasgow.2. The notifications of pneumonia do not represent the true incidence of the disease, though there is reason to believe that in Glasgow they represent about 76 per cent. of the total cases.3. It has been shown that in Glasgow the pneumonia mortality in children under five years is closely related to environmental conditions.4. Evidence has been adduced to suggest that the mortality figures for pneumonia in children under five years are considerably influenced by out breaks of measles and whooping cough, especially the former.5. There has been in Glasgow since 1855 a striking alteration in the conception of what constitutes bronchitis and broncho-pneumonia in children under five years; what is now recognised as broncho-pneumonia once was largely certified as bronchitis.
The Life-cycle of Bacteria. Alternate Asexual and Autogamic Phases
Authors: Stewart F. H. 
Published: May 2009

I. Life-Cycle. Colony Formation, Sporing, Papilla Formation.If any bacterium is sown in the usual way from a fluid suspension on to a plate of suitable culture medium, colonies arise from the multiplication of single bacteria. These colonies grow at their margins ar a rate roughly constant for the species. When the colony has reached a certain size, which is again roughly constant for the species, it ceases to grow or continues growing very slowly. Thus for example colonies of streptococci grow to 1 mm. in diameter, those of coliforms to 3 or 6 mm. The colonies do not continue to grow until they have covered the whole plate. This limitation of growth is not due to the using up of the food supply or to the drying of the medium, since, if a second sowing of the same bacterium is made between the arrested colonies, a new crop of colonies arises.1 Twort (1907) obtained lactose fermenting variants ofB. typhosusafter prolonged growth in this sugar. These variations do not however occur frequently and regularly. They are probably examples of mutation from a homozygous strain (Mode A above).2 The variations mentioned take place in culture where their origin from papillae can be seen. It is likely that exaltation of virulence is an adaptive variation of the same kind occurring in a host.
Scarlatina Immunity In Hong Kong
Authors: Davis L. J. , Guzdar J. S. , Fernando F. S. 
Published: May 2009

1. In Hong Kong, where scarlet fever is extremely rare, the Dick reactions of a random sample of 921 Chinese were ascertained. Positive reactions were obtained in 19·1 per cent. The distribution of positive reactors in different age groups is recorded; it bears a general similarity to those recorded by various observers in Europe and the U.S.A.2. A haemolytic streptococcal carrier rate of 6·6 per cent, was determined by nasopharyngeal swabbing of 1600 Hong Kong Chinese. The frequency of haemolytic streptococci was higher during the cooler months of the year and among the younger age groups.3. Erythrogenic toxin production and fibrinolytic activity were demonstrated in a number of the strains of streptococci isolated from apparently normal throats.4. The significance of these findings is discussed.
The Demonstration of the Increase of Globulin in Diphtheria Antitoxins by the Precipitation Reaction
Authors: Taylor G. L. 
Published: May 2009

1. By titration against horse serum and its protein fractions anti-horse sera can be divided into three groups, according to the antibodies responsible for the main or earliest particulating zone, namely the sera containing antibodies against (a) globulin only, (b) albumin only, and (c) both globulin and albumin.2. For the quantitative estimation of a protein fraction in a horse serum it is necessary to use an antiserum containing a main zone antibody acting with that protein only.This is illustrated in experiments, designed to show the increased globulin content of diphtheria antitoxin, in which antisera containing antibodies against both globulin and albumin failed to register an increase in the globulin content.
A Study of the Streptococci from Fifty cases of Bovine Mastitis
Authors: Gibson H. J. , Muir R. O. 
Published: May 2009

Fifty-one strains recently isolated from cases of bovine mastitis have been studied in their morphological, cultural and biochemical reactions.Using their colony appearance in blood agar as the first differential criterion we have shown that the strains differ widely from one another and from the α β and γ streptococci usually encountered in human disease.The heterogeneity of mastitis streptococci was strikingly demonstrated. From the results of a relatively small number of cultural and biochemical tests it could be shown that no two of the fifty-one strains were identical, in every respect.The findings recorded suggest that great caution must be exercised in ascribing a bovine or human origin to individual strains of streptococci on the results of cultural or biochemical reactions.
Tuberculin Reactions of the Hong Kong Chinese, with special reference to the use of Tuberculo-Protein
Authors: Davis L. J. , Guzdar J. S. 
Published: May 2009

1. The tuberculin reactions of 259 Hong Kong Chinese, mostly adults, were determined by the Mantoux method. Each individual was tested with various dilutions of both old tuberculin and tuberculo-protein.2. Of 215 subjects above the age of twenty, 93·1 per cent, yielded positive reactions to old tuberculin in dilutions of 1/1000 or higher.3. Tuberculo-protein compared with old tuberculin of similar dilutions did not yield such a high percentage of positive reactions, seldom produced such vigorous reactions and never caused vesiculation. (This may have been due to deterioration.)
Virulence and Immunogenic Activities ofB. Typhosusin Relation to its Antigenic Constituents
Authors: Felix A. , Pitt R. M. 
Published: May 2009

1. Rough variants, derived from strains ofB. typhosuswhich possess the Vi antigen, may still contain this antigen though the smooth O antigen has been lost.2. Such variants, which are non-virulent, are yet capable of inducing active and passive immunity.3. The virulence ofB. typhosusdepends on the combined activity of the smooth O and the Vi antigen. Nevertheless the Vi antibody alone is sufficient to protect against infection with strains of the highly virulent type.4. The use of avirulent, rough, but Vi-containing variants as vaccines and in the preparation of therapeutic sera is discussed.