scholarly journals STUDIES ON TYPHUS FEVER

1931 ◽  
Vol 53 (3) ◽  
pp. 325-331 ◽  
Author(s):  
Hans Zinsser ◽  
M. Ruiz Castaneda
Keyword(s):  
Guinea Pigs ◽  
Theoretical Basis ◽  
Active Immunization ◽  
Human Beings ◽  
Etiological Factors ◽  
Typhus Fever

We have adduced evidence that guinea pigs can be completely or partially protected by three injections of typhus tunica material in which there are moderate numbers of Rickettsiae, treated for from 24 to 48 hours with a 0.2 per cent formalin solution. We believe that the immunization is due to the presence of the Rickettsiae, since in our preceding experiments we have satisfied ourselves that these organisms are the true etiological factors of the disease. For the reasons stated above, we believe that the formalinized vaccine does not contain living, but attenuated organisms, and that the immunizing effect is the result of treatment with formalin-killed Rickettsiae. This point, however, we admit, is not absolutely determined. These experiments, together with the results obtained in the concentration of Rickettsia material by the diet method of reducing resistance as described in the paper which follows, furnish a hopeful method and a reasonable theoretical basis for a procedure of active immunization against this disease in human beings.

scholarly journals STUDIES ON TYPHUS FEVER

1931 ◽  
Vol 53 (4) ◽  
pp. 493-497 ◽  
Author(s):  
Hans Zinsser ◽  
M. Ruiz Castaneda
Keyword(s):  
Guinea Pigs ◽  
Spotted Fever ◽  
Rocky Mountain ◽  
Active Immunization ◽  
Rocky Mountain Spotted Fever ◽  
Typhus Fever

Guinea pigs can be immunized against Mexican typhus virus by peritoneal injections of formalinized Rickettsia material, provided sufficient amounts of the organisms are used. Our results in this respect are analogous to those of Spencer and Parker with carbolized virus of Rocky Mountain spotted fever. The Rickettsia suspensions appear to possess considerable toxicity. We do not wish to be misunderstood as implying that the results in guinea pigs offer anything more than a demonstration of the principle of active immunization with killed Rickettsiae. Application to man will have to be worked out, and preliminary to this, we are now attempting to apply the methods to a limited number of monkeys.

scholarly journals STUDIES ON TYPHUS FEVER

1931 ◽  
Vol 53 (3) ◽  
pp. 333-338 ◽  
Author(s):  
Hans Zinsser ◽  
M. Ruiz Castaneda ◽  
C. V. Seastone
Keyword(s):  
Tissue Culture ◽  
Guinea Pigs ◽  
Preceding Paper ◽  
Severe Infection ◽  
Active Immunization ◽  
Point Of View ◽  
Deficiency Symptoms ◽  
Clinical Pictures ◽  
Typhus Fever

The above experiments demonstrate that guinea pigs and rats subjected to vitamin-deficient diets to a point at which deficiency symptoms appear, and then inoculated with typhus virus, exhibit clinical pictures which indicate a far more severe infection than that observed in normal animals after inoculation. There is also a wider distribution of Rickettsiae and a concentration of organisms which, in pleural and peritoneal exudates, amounts to almost cultural proportions. Important from our point of view is the fact that these experiments furnished a step toward the accomplishment of our purpose, which was to obtain amounts and concentrations of Rickettsiae suitable for immunological studies until such a time when tissue culture may have developed to a practically useful stage. The experiments are of immediate importance in that they furnish us a method for improving our technique of active immunization reported upon in the preceding paper, No. V (8). From the epidemiological point of view these experiments at least suggest an explanation of one of the important factors which enter into the historical association of high typhus mortality with war and famine.

Simulating Crime Events and Crime Patterns in a RA/CA Model

2005 ◽  
pp. 197-213 ◽  
Author(s):  
Lin Liu ◽  
Xuguang Wang ◽  
John Eck ◽  
Jun Liang
Keyword(s):  
Simulation Model ◽  
Theoretical Basis ◽  
Psychological Impact ◽  
Routine Activities ◽  
Human Beings ◽  
Data Set ◽  
Crime Patterns ◽  
State Variable ◽  
Ca Model ◽  
Experimental Runs

This chapter presents an innovative approach for simulating crime events and crime patterns. The theoretical basis of the crime simulation model is routine activities (RA) theory. Offenders, targets and crime places, the three basic elements of routine activities, are modeled as individual agents. The properties and behaviors of these agents change in space and time. The interactions of these three types of agents are modeled in a cellular automaton (CA). Tension, measuring the psychological impact of crime events to human beings, is the state variable of the CA. The model, after being calibrated by using a real crime data set in Cincinnati, is able to generate crime patterns similar to real patterns. Results from experimental runs of the model conform to known criminology theories. This type of RA/CA simulation model has the potential of being used to test new criminology theories and hypotheses.

scholarly journals A STUDY OF THE RELATIONSHIP OF THE SCROTAL SWELLING AND RICKETTSIA BODIES TO MEXICAN TYPHUS FEVER

1930 ◽  
Vol 52 (2) ◽  
pp. 195-199 ◽  
Author(s):  
M. Ruiz Castaneda
Keyword(s):  
Guinea Pig ◽  
Guinea Pigs ◽  
Human Case ◽  
Tunica Vaginalis ◽  
Two Generations ◽  
Scrotal Swelling ◽  
Typhus Fever ◽  
Relationship Of ◽  
The Relationship

The experiments recorded above have demonstrated the following points: 1. Scrotal swelling can appear in guinea pigs directly inoculated from a human case of Mexican typhus fever. 2. In certain strains of this disease, a number of generations of guinea pigs may show absolutely no scrotal swelling, which, however, may reappear in subsequent animals, suggesting—though not absolutely proving—that the scrotal swelling is an integral part of the disease and is not due to an incidental accompanying organism. If the latter were true, one would expect the organisms that caused the scrotal swelling to disappear during the negative generations. 3. A typhus fever sustained by a guinea pig without scrotal swelling protects against the swelling upon subsequent inoculation with a strain which produces this with considerable regularity. 4. Louse passage increases the capacity of a strain to produce the scrotal lesion, probably because of the considerable accumulation of rickettsia in the louse, but in the experiment noted, even after louse passage, two generations without swelling occurred, followed by reoccurrence of the swelling. We believe that these observations, taken together, can be interpreted in favour of the likelihood that the swelling is a part of the disease and that the rickettsia-like organisms described by Mooser in the tunica vaginalis have etiological significance.

scholarly journals Absence of Glomerulonephritis in Guinea Pigs Deficient in the Fourth Component of Complement

1994 ◽  
Vol 31 (2) ◽  
pp. 201-206 ◽  
Author(s):  
C. J. Foltz ◽  
L. C. Cork ◽  
J. A. Winkelstein
Keyword(s):  
Renal Disease ◽  
Microscopic Examination ◽  
Guinea Pigs ◽  
Electron Microscopic Examination ◽  
Complement C3 ◽  
Human Beings ◽  
Electron Microscopic ◽  
Classical Complement Pathway ◽  
Fourth Component ◽  
Genetically Determined

Genetically determined deficiencies of the early components of the classical complement pathway (CI, C4, C2) or of the third component of complement (C3) in both human beings and experimental animals are known to be associated with renal disease, including glomerulonephritis. The current study was performed to examine the C4–deficient (C4D) guinea pig for the presence of renal disease. Eighteen C4D animals and 17 control animals (Crl:Hartlcy) (divided by sex into four age categories) were examined. Light microscopic examination revealed no differences in mesangium, glomerular cellularity, thickness of capillary loops, or presence of epithelial crescents in the kidneys of C4D guinea pigs as compared with control animals. Electron microscopic examination did not reveal glomerular or tubular immune complex deposits in either C4D or control animals. C4D guinea pigs apparently do not demonstrate glomerulonephritis.

scholarly journals The Ticks of Rodents and their Nests, and the Discovery that Rhipicephalus sanguineus Latr. is the Vector of Tropical Typhus in Kenya

1935 ◽  
Vol 35 (1) ◽  
pp. 1-22 ◽  
Author(s):  
J. Isgaer Roberts
Keyword(s):  
Guinea Pig ◽  
Positive Result ◽  
Guinea Pigs ◽  
Rhipicephalus Sanguineus ◽  
Weather Conditions ◽  
Human Beings ◽  
Negative Results ◽  
Unfavourable Weather ◽  
The Subject ◽  
Made In

1. Earlier attempts to trace the vector of tropical typhus in Kenya failed. The only references to the subject in the available literature consist of mere suggestions that a mite would most likely prove to be the transmitter.2. An investigation made in an area whence most Nairobi cases of tropical typhus were reported, suggested that a tick (R. pulchellus) would be the most likely vector.3. Transmission experiments made in the belief that one of the unclassed fevers of man was conveyed by R. pulchellus have so far yielded negative results. There is, however, sufficient circumstantial evidence available pointing to this tick as vector of a form of mild typhus to man—this demands further investigation.4. At Mombasa and Nairobi, houses reported to be heavily infested with ticks, or houses investigated after the occurrence of the tropical typhus in them, have yielded only R. sanguineus.5. R. sanguineus (3 ♀), taken from a dog in a house where the last typhus case had occurred 8 months previously, gave a typical typhus syndrome when emulsified and inoculated into a male guinea-pig. R. sanguineus (1 ♀, 12 ⊙), taken in a house where a child had recently contracted typhus, also gave a positive result with guinea-pigs and the virus was further transmitted by passage through other guinea-pigs.6. The infestation of houses by R. sanguineus and the incidence of tropical typhus among human beings appear to be influenced by unfavourable weather conditions, causing the ticks to seek relatively dry and warm places for purposes of oviposition or metamorphosis, thus invading houses. In the absence of dogs, its usual hosts, the tick attacks man.

scholarly journals Active immunization against GnRH in pre-pubertal domestic mammals: testicular morphometry, histopathology and endocrine responses in rabbits, guinea pigs and ram lambs

animal ◽  
2018 ◽  
Vol 12 (4) ◽  
pp. 784-793 ◽  
Author(s):  
P.M. Aponte ◽  
M.A. Gutierrez-Reinoso ◽  
E.G. Sanchez-Cepeda ◽  
M. Garcia-Herreros
Keyword(s):  
Guinea Pigs ◽  
Active Immunization ◽  
Ram Lambs
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