scholarly journals NUTRITION OF THE HOST AND NATURAL RESISTANCE TO INFECTION

1948 ◽  
Vol 87 (2) ◽  
pp. 103-118 ◽  
Author(s):  
Howard A. Schneider
Keyword(s):  
Natural Resistance ◽  
Assay Method ◽  
Time Interval ◽  
Pathogen Population ◽  
Optimum Time ◽  
Natural Diet ◽  
Synthetic Diet ◽  
Whole Wheat ◽  
Resistance To Infection ◽  
The Relationship

The observation has been confirmed that the property of a "natural" diet of whole wheat and whole dried milk to promote a higher survival rate among a stock of outbred, genetically heterogeneous W-Swiss mice subjected to S. typhimurium infection, over that promoted by a "synthetic" diet, is dependent upon a relationship between avirulent and virulent members of the pathogen population. This relationship has now been analyzed in terms of number (interacting doses) and time (interval between interacting doses). On any given diet survivorship has been demonstrated to be a function of the host's experience of the avirulent pathogen; increasing experience, either in dose or time, resulted in increasing survivorship. For a given set of interacting avirulent-virulent doses the rate at which survivorship rose was greater when the "natural" diet was fed than when the "synthetic" diet was fed. This difference in survivorship-increase rates gave rise to differences in survivorship between the two diets. These dietary differences ranged from minimal to maximal with increasing time, and then, as still more time elapsed, back to minimal again. In consequence an optimum time interval was found at which the dietary effect was maximal. This time interval was chosen for assay purposes. The assay method thus arrived at was tested repeatedly for reproducibility, and statistical analysis showed it to be reliable and capable of demonstrating a mean dietary difference in survivorship of 55 per cent. The nature of the relationship established between avirulent and virulent S. typhimurium in mice has been discussed.

scholarly journals NUTRITION OF THE HOST AND NATURAL RESISTANCE TO INFECTION

1949 ◽  
Vol 89 (5) ◽  
pp. 529-539 ◽  
Author(s):  
Howard A. Schneider
Keyword(s):  
Inbred Mouse ◽  
Natural Resistance ◽  
Single Infection ◽  
Mouse Strains ◽  
Time Interval ◽  
Special Cases ◽  
Resistance To Infection ◽  
Relationship Of ◽  
First Time ◽  
The Relationship

The double strain inoculation (DSI) method of testing for natural resistance to infection has been examined in the instance of mouse salmonellosis. The DSI method has been found capable of detecting differences in natural resistance due to genetic as well as nutritional causes. A difference in response to Salmonella infection was found for the first time between the two "susceptible" inbred mouse strains, BSVR and BSVS. Whereas BSVS mice for the most part survived an intraperitoneal injection of 103 "avirulent" S. typhimurium, BSVR mice all succumbed. The relationship of the DSI test to the usual single infection test has been discussed and it is suggested that such single infection tests are special cases of the DSI test, since they involve a heterogeneous bacterial population which can be considered as a mixture of cultures of differing virulence and in which, by a single injection, the usual time interval between the two injections of the DSI method has been reduced to 0.

scholarly journals NUTRITION OF THE HOST AND NATURAL RESISTANCE TO INFECTION

1946 ◽  
Vol 84 (4) ◽  
pp. 305-322 ◽  
Author(s):  
Howard A. Schneider
Keyword(s):  
Survival Rate ◽  
Bacterial Population ◽  
Natural Resistance ◽  
Bacterial Populations ◽  
Synthetic Diet ◽  
Swiss Mice ◽  
Whole Wheat ◽  
Resistance To Infection ◽  
Difference Effect

The property of a diet of whole wheat and whole dried milk to promote a higher survival rate among a stock of heterogenetic, outbred W-Swiss mice subjected to S. enteritidis infection, over that promoted by a "synthetic" diet, has been shown to be a function of the infecting bacterial population. Broth cultures so prepared as presumably to yield S. enteritidis organisms of uniform character have consistently failed to reveal an effect of diet on natural resistance, even though the parent bacterial populations revealed a dietary effect. The dietary difference effect on natural resistance could not be demonstrated with an avirulent culture of S. typhimurium, or with a freshly prepared virulent culture of S. typhimurium presumably uniform in character. The dietary effect on natural resistance was demonstrated by employing a 1:1 mixture of avirulent and virulent cultures of S. typhimurium.

scholarly journals NUTRITION OF THE HOST AND NATURAL RESISTANCE TO INFECTION

1956 ◽  
Vol 103 (2) ◽  
pp. 207-223 ◽  
Author(s):  
Howard A. Schneider ◽  
Norton D. Zinder
Keyword(s):  
Population Size ◽  
Natural Resistance ◽  
Mouse Spleen ◽  
Inoculation Test ◽  
Nutritional Factors ◽  
Deficiency State ◽  
Synthetic Diet ◽  
Resistance To Infection ◽  
Positive Effect

The double strain inoculation test as used for the assay of nutritional factors capable of enhancing survivorship in mouse salmonellosis has been modified and improved. The modification has been based on the use of genetically marked strains of S. typhimurium, and substitutes for survivorship a bacteriological datum, a certain minimum population size of the virulent salmonellae in the mouse spleen at a certain time. The analysis permitting this substitution and the economies achieved by the modification has been presented. In the course of development of the new assay evidence was obtained that the nutrient entity or entities responsible for enhanced survivorship, as measured by the bacteriological correlate, are not stored in the mouse. A deficiency state was achieved 24 hours after supplying the basal synthetic diet. Similarly, positive effect of active nutrients was evident as soon as 24 hours after feeding.

scholarly journals THE EFFECT OF DIET ON THE FECAL BACTERIAL FLORA OF MICE AND ON THEIR RESISTANCE TO INFECTION

1962 ◽  
Vol 115 (6) ◽  
pp. 1161-1172 ◽  
Author(s):  
René J. Dubos ◽  
Russell W. Schaedler
Keyword(s):  
Experimental Infection ◽  
Bacterial Flora ◽  
Wheat Gluten ◽  
Sole Source ◽  
Casein Diet ◽  
Synthetic Diet ◽  
Whole Wheat ◽  
Large Numbers ◽  
Whole Milk ◽  
Resistance To Infection

A study was made of the effect of certain dietary regimens on the lactobacillus flora in the stools of mice and on their resistance to infection. Semi-synthetic diets with purified casein or wheat gluten as sole source of protein, gave rise to much smaller numbers of viable lactobacilli in the stools than did other diets containing unidentified natural products—as present for example in mixtures of whole wheat and whole milk, or in certain commercial pellets. Furthermore, one of the lactobacillus types with rhizoid morphology disappeared completely from the stools of animals fed the semi-synthetic diet. The change in the lactobacillus flora became apparent within a very few days after the animals had been shifted from the complex to the synthetic diet Moreover, this change was not completely reversible. Whereas the total numbers of lactobacilli increased when the animals were shifted back from the synthetic to the complex diets, the rhizoid lactobacilli which had disappeared completely from the stools reappeared only slowly or not at all. In twelve consecutive experiments the three diets which gave rise to the large numbers of lactobacilli in the stools also conferred on the mice a much higher resistance to experimental infection with Staphylococcus aureus and Klebsiella pneumoniae, than did the semi-synthetic diets. However, direct evidence has not yet been obtained that the two kinds of phenomena were causally related. Following administration of endotoxin there was a rapid and very large increase in the numbers of enterococci and coliform bacilli in mice fed the semi-synthetic casein diet, but not in those fed the pellets. In two preliminary experiments carried out with another colony of mice, not pathogen-free, it was also found that the rhizoid type of lactobacilli disappeared from animals fed the semi-synthetic casein diet while enterococci and coliform bacilli progressively increased in numbers under the same conditions. The dietary effects on the lactobacillus flora, and on resistance to experimental infection, were equally pronounced whether the mice were housed in individual cages on wire grids, or grouped in larger cages with wood shavings as litter. This was true even if the bedding was changed only once weekly and became therefore grossly soiled.

scholarly journals NUTRITION OF THE HOST AND NATURAL RESISTANCE TO INFECTION

1945 ◽  
Vol 81 (4) ◽  
pp. 359-384 ◽  
Author(s):  
Howard A. Schneider ◽  
Leslie T. Webster
Keyword(s):  
Survival Rate ◽  
Inbred Strains ◽  
Natural Resistance ◽  
Genetic Constitution ◽  
Nutritional Factors ◽  
Swiss Mice ◽  
Whole Wheat ◽  
Inbred Strains Of Mice ◽  
Whole Milk ◽  
Resistance To Infection

1. A diet of whole wheat and whole dried milk has been shown to promote a higher survival rate, among W-Swiss mice subjected to S. enteritidis infection, than that promoted by a "synthetic" diet. 2. The demonstration of this ability of diet to condition natural resistance has been found to depend upon the genetic constitution of the mice employed. The demonstration has been possible in W-Swiss mice, a strain only moderately inbred and retaining a degree of genetic variability. The demonstration has not been possible in three highly inbred strains of mice selected so that they differed predictably from one another in natural resistance. 3. The nutritional factors involved are present in whole wheat and are absent or negligible in dried whole milk. Their nature has not yet been determined.

TO STUDY THE DYNAMICS OF IMMUNITY IN BLACK-AND-WHITE COWS DEPENDING ON AGE

2020 ◽  
pp. 49-52
Author(s):  
М.В. ДОВЫДЕНКОВА
Keyword(s):  
Bactericidal Activity ◽  
Phagocytic Activity ◽  
Physiological State ◽  
Age Groups ◽  
Statistical Processing ◽  
Natural Resistance ◽  
Black And White ◽  
Feeding Methods ◽  
High Degree ◽  
The Relationship

Проведена статистическая обработка сформированной базы данных показателей неспецифической резистентности MS «Excel» с целью изучения динамики иммунитета по параметрам бактерицидной, лизоцимной и фагоцитарной активности у крупного рогатого скота черно-пестрой породы разных возрастов. Было установлено, что средние значения показателей лизоцимной и бактерицидной активности у телят в 6 мес были ниже (47,89% и 49,09%, соответственно), чем у животных в 3—4 года (53,75% и 52,81%). Выведено уравнение регрессии, описывающее взаимосвязь между средними показателями фагоцитарной активности и возрастом при высокой степени достоверности (R2=0,90). Изменения лизоцимной и бактерицидной активности в зависимости от возраста были недостоверными (R2=0,58 и R2=0,49, соответственно). Установлена высокая корреляция между бактерицидной и лизоцимной активностью. Отмечена динамика изменения неспецифического иммунитета у коров различных возрастных групп. Создание баз данных и постоянный мониторинг основных показателей естественной резистентности в зависимости от различных факторов (породы, возраста, стадий лактации, кормления, способов содержания), которые влияют на данные показатели, необходимо для оценки физиологического состояния организма животных и их устойчивости к болезням. Statistical processing of the generated MS "Excel" on indicators of non-specific resistance database was carried out with the aim of studying the dynamics of the development of immunity in terms of bactericidal, lysozyme and phagocytic activity in black-and-white cattle of different ages. It was found that the average values of indicators of lysozyme and bactericidal activity in calves at 6 months were lower (47.89% and 49.09%, respectively) than in animals at the age of 3—4 years (53.75% and 52.81%). The equation of regression was derived, it describes the relationship between the average indicators of phagocytic activity and the age with a high degree of reliability (R2=0.90). The changes in lysozyme and bactericidal activity depending on age were dubious (R2=0.58 and R2=0.49, respectively). The high correlation between bactericidal and lysozyme activity was established. It was noticed that the cows of different age groups experienced the dynamics of changes in nonspecific immunity. The creation of databases and constant monitoring of the main indicators of natural resistance, depending on various factors (breed, age, stages of lactation, feeding, methods of keeping) that affect these indicators, is necessary for assessing the physiological state of the animals’ body of and their resistance to diseases.

Certain aspects of the host-parasite relationship ofNematospiroides dubius(Baylis). II. The effect of sex on experimental infections in the rat (an abnormal host)

Parasitology ◽  
1961 ◽  
Vol 51 (3-4) ◽  
pp. 499-510 ◽  
Author(s):  
Colin Dobson
Keyword(s):  
Male Rats ◽  
Male Rat ◽  
Normal Male ◽  
Female Rat ◽  
Castrate Male ◽  
Parasite Relationship ◽  
Nematospiroides Dubius ◽  
Resistance To Infection ◽  
Host Parasite ◽  
The Relationship

1. The male rat is more susceptible to infections ofNematospiroides dubiusthan the female. As the rat grows older the resistance of the female rat to infection increases at a greater rate than that of the male.2. The course of the infection is modified by the sex of the host.3. More larvae penetrated the intestinal mucosa to encyst in the male than in the female. More larvae, however, formed cysts in the female than in the male rat by the fifth day.4. The male harboured more adult worms than the female rat, although this difference was not significant in the immature animals.5. The sex resistance of the rat toN. dubiusinfections was removed by bilateral gonadectomy. Castration decreased the susceptibility of the male rat, while spaying increased it in the female compared with the susceptibility in the respective normal hosts.6. Subsequent replacement of the homologous sex hormone in the gonadectomized rat restores the sex resistance, and may even increase it (particularly in the immature animals). Oestradiol increased the resistance of the spayed female rat, while testosterone increased the susceptibility of the castrate male rat to infection.7. Oestradiol implanted in castrate male rats increased the resistance of these hosts to a greater level than was shown in the normal male rat.8. The rat shows a marked age resistance over which the sex resistance is superimposed.9. The relationship between the sex of the host and its resistance to infection is discussed.This work was done during the tenure of a Department of Scientific and Industrial Research Studentship. My thanks are due to Dr E. T. B. Francis for his helpful and critical supervision and to Professor I. Chester Jones, in whose department the work was done, for the facilities he provided.

scholarly journals Impact of diet on the immunological microenvironment of the pregnant uterus and its relationship to allergic disease in the offspring: a review of the recent literature

2006 ◽  
Vol 124 (5) ◽  
pp. 298-303 ◽  
Author(s):  
Daniella Campelo Batalha Cox Moore ◽  
Pedro Xavier Elsas ◽  
Elisabeth Santos Maximiano ◽  
Maria Ignez Capella Gaspar Elsas
Keyword(s):  
Allergic Disease ◽  
Allergic Diseases ◽  
Perinatal Period ◽  
Time Interval ◽  
Industrialized Countries ◽  
Pregnant Uterus ◽  
Medical Progress ◽  
Immunological Profile ◽  
Dietary Content ◽  
The Relationship

Medical progress has reduced the mortality from infectious diseases in most countries, but allergic diseases have become more prevalent worldwide over the same period, especially in industrialized countries. This has prompted speculation that modern lifestyles have altered the relationship between heredity and environment so as to promote development of an atopic phenotype when exposure to infection decreases. A healthy uterine microenvironment is known to favor Th2 lymphocyte development. However, some evidence suggests that persistence of the Th2 pattern of immunity directs the developing organism's immune response towards a long-lasting atopic phenotype. Even though the outcome also depends on other factors (such as infection, functional state of the intestinal microflora, and exposure to environmental allergens at times critical to development), it seems that the immune system during the perinatal period is responsive to interventions that are no longer effective in adulthood. We have reviewed the literature accessible through Medline to identify recent advances in the prevention of allergic disease through interventions in the fetal-maternal relationship. Diet seems to have a significant impact on the immunological profile of the pregnant uterus, as well as on the postnatal development of allergic disease in the offspring, as suggested by the effects of probiotic bacteria and by manipulations of the dietary content of polyunsaturated fatty acids and antioxidants. This highlights the need for further studies, in order to define the best intervention methods, the most appropriate time interval and the individuals who will most likely benefit from them.

scholarly journals Influence of the Bcg Locus on Natural Resistance to Primary Infection with the Facultative Intracellular Bacterium Francisella tularensis in Mice

2000 ◽  
Vol 68 (3) ◽  
pp. 1480-1484 ◽  
Author(s):  
Hana Kovářová ◽  
Lenka Hernychová ◽  
Marián Hajdúch ◽  
M. Šírová ◽  
Aleš Macela
Keyword(s):  
Francisella Tularensis ◽  
Bacterial Colonization ◽  
Phenotypic Expression ◽  
Interleukin 10 ◽  
Natural Resistance ◽  
Mouse Strains ◽  
Oxygen Intermediates ◽  
Necrosis Factor Alpha ◽  
Factor Alpha ◽  
Resistance To Infection

ABSTRACT The implication of the Bcg locus in the control of natural resistance to infection with a live vaccine strain (LVS) of the intracellular pathogen Francisella tularensis was studied. Analysis of phenotypic expression of natural resistance and susceptibility was performed using mouse strains congenic at theBcg locus. Comparison of the kinetics of bacterial colonization of spleen showed that B10.A.Bcg(r) mice were extremely susceptible during early phases of primary sublethal infection, while their congenic C57BL/10N [Bcg(s)] counterparts could be classified as resistant to F. tularensis LVS infection according to the 2-log-lower bacterial CFU within the tissue as long as 5 days after infection. Different phenotypes of Bcg congenic mice were associated with differential expression of the cytokines tumor necrosis factor alpha, interleukin-10, and gamma interferon and production of reactive oxygen intermediates. These results strongly suggest that the Bcglocus, which is close or identical to the Nramp1 gene, controls natural resistance to infection by F. tularensisand that its effect is the opposite of that observed for otherBcg-controlled pathogens.

EVALUATION OF PROTEIN IN FOODS: IV. A SIMPLIFIED CHEMICAL SCORE

1959 ◽  
Vol 37 (1) ◽  
pp. 1293-1299 ◽  
Author(s):  
J. M. McLaughlan ◽  
C. G. Rogers ◽  
D. G. Chapman ◽  
J. A. Campbell
Keyword(s):  
Rapid Screening ◽  
Assay Method ◽  
Efficiency Ratio ◽  
Lysine Concentration ◽  
Chemical Score ◽  
Group A ◽  
High Degree ◽  
The Relationship ◽  
Bio Assay

Available evidence has shown that most common foods are deficient in lysine, methionine, or in methionine and cystine. Based on the determination of these amino acids, a simplified chemical score was developed and compared with protein efficiency ratio (P.E.R.) values determined with the same samples. Each of 43 foods was assigned to either of two categories: (a) foods apparently deficient in lysine or (b) in methionine (+ cystine). With 16 foods in the former group there was a high degree of correlation between lysine concentration and P.E.R. With 27 foods in the latter group, a good correlation was found between the methionine (+ cystine) concentration and P.E.R. Since the regression lines for the two groups were different, a factor was added to the methionine (+ cystine) values to simplify the relationship. That foods deficient in lysine or in methionine (+ cystine) fell into two distinct groups appeared to be substantiated by data available in the literature. Because the simplified method is relatively rapid, yields reproducible results, and correlates with animal assays, it is proposed as a rapid screening procedure for the evaluation of protein in foods, but is not intended to replace the rat bio-assay method.

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