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Allergenicity of Mycobacterial Ribosomal and Ribonucleic Acid Preparations in Mice and Guinea Pigs 总被引:18,自引:3,他引:15
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Guinea pigs were injected subcutaneously with mycobacterial ribosomal fraction incorporated in Freund's incomplete adjuvant and tested 6 and 12 weeks later by the intradermal injection of 0.5 μg (25 TU) of Purified Protein Derivative. No evidence of delayed-type hypersensitivity could be detected in these animals, although large necrotic reactions were obtained in guinea pigs sensitized with living, attenuated mycobacterial cells. Mice also were vaccinated by the intraperitoneal injection of mycobacterial ribosomal fraction or ribonucleic acid (RNA) and tested for sensitivity to tuberculin at various subsequent times. No evidence of true tuberculin hypersensitivity could be detected at any time, although what appeared to be small Arthus type reactions were seen in mice given the largest vaccinating doses. Attempts to recall tuberculin sensitivity in vaccinated mice by the intravenous injection, 4 weeks after vaccination of living cells, of either the virulent or attenuated mycobacterial strains were unsuccessful. Instead, when the virulent cells were injected, a suppression of footpad reactivity was noted in animals made sensitive to tuberculin by the previous intraperitoneal injection of viable attenuated mycobacterial cells. Both guinea pigs and mice, vaccinated as described above, were also skin tested or footpad tested, respectively, with 2 μg of the ribosomal fraction or RNA used for vaccination. No evidence of true tuberculin hypersensitivity could be obtained; instead, in guinea pig skin very small dermonecrotic areas were noted, and in mice swelling and redness of the footpad occurred to an equal extent in both vaccinated and nonvaccinated mice. The possible role of tuberculin hypersensitivity in acquired immunity to tuberculosis is discussed, and the conclusion is reached that its part, if any, is minor. 相似文献
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Factors Affecting Immunogenic Activity of Mycobacterial Ribosomal and Ribonucleic Acid Preparations 总被引:28,自引:0,他引:28
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By following careful procedures, mycobacterial ribosomal fractions and ribonucleic acid (RNA) prepared by ethyl alcohol precipitation were obtained which have immunogenic activities similar to the viable attenuated H37Ra cells of Mycobacterium tuberculosis from which they were obtained. This comparison was based on the amount of ribonucleic acid (RNA) present. These preparations consisted of approximately 63% RNA and 37% protein; no deoxyribonucleic acid or polysaccharide was detected by chemical tests. A high correlation was found between the immunogenic activity of a preparation and the per cent increase in hyperchromicity at 260 nm of a ribonuclease-hydrolyzed portion. Final concentrations of sodium dodecyl sulfate higher than 0.25% when used for the preparation of the ribosomal fractions and RNA resulted in significantly lower immune responses and greater variation between experiments. This was not related to the amount of protein present. The stability of the ribosomal and RNA preparations was tested under a variety of conditions. The need for a good protective adjuvant again was shown since mouse serum readily hydrolyzed the RNA. Equal immunity was obtained after immunization by the intraperitoneal and subcutaneous routes; however, no immune response was obtained when the intravenous route was used. Preliminary results with RNA prepared with phenol showed that it was more easily degraded during preparation. This resulted in a lower immune response than was obtained with the RNA prepared with ethyl alcohol. 相似文献
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From a survey of the literature on follicular lymphoma it appears that the lesion of Brill-Symmers disease may be considered to be a form of neoplasm. The authors have reviewed a series of 18 cases seen at the Hôtel-Dieu of Québec between 1950 and 1960 and have adopted Rappaport''s classification published in 1956, but leaving out the “Hodgkin” Type 5 which they propose to examine more fully in another paper.There appears to be a degree of positive correlation between the histologic type and the course of the disease, the well differentiated cell Type 1 being associated with a protracted course. This neoplasm should not be mistaken for benign follicular hyperplasia. 相似文献
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Structural Aspects of Saltatory Particle Movement 总被引:8,自引:0,他引:8
Lionel I. Rebhun 《The Journal of general physiology》1967,50(6):223-239
A variety of cells possess particles which show movements statistically different from Brownian movements. They are characterized by discontinuous jumps of 2–30 µ at velocities of 0.5–5 µ/sec or more. A detailed analysis of these saltatory, jumplike movements makes it most likely that they are caused by transmission of force to the particles by a fiber system in the cell outside of the particle itself. Work with isolated droplets of cytoplasm from algae demonstrates a set of fibers involved in both cytoplasmic streaming and saltatory motion, suggesting that both phenomena are related to the same force-generating set of fibers. Analysis of a variety of systems in which streaming and/or saltatory movement occurs reveals two types of fiber systems spatially correlated with the movement, microtubules and 50 A microfilaments. The fibers in Nitella (alga) are of the microfilament type. In other systems (melanocyte processes, mitotic apparatus, nerve axons) microtubules occur. A suggestion is made, based on work on cilia, that a microtubule-microfilament complex may be present in those cases in which only microtubules appear to be present, with the microfilament closely associated with or buried in the microtubule wall. If so, then microfilaments, structurally similar to smooth muscle filaments, may be a force-generating element in a very wide variety of saltatory and streaming phenomena. 相似文献
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Twenty-seven adults with acute poststreptococcal glomerulonephritis were divided into two groups according to the severity of reduction in renal function: (1) 14 patients with mild depression of renal function, and (2) 13 patients with more severe renal insufficiency. In the first group the outcome was favourable, with complete clinical recovery in 11 patients. Only two patients in the second group have recovered. Five have died of renal failure and in six the chronic stage has developed. The most notable histopathological lesion observed in this group of patients was severe proliferative glomerulonephritis with a large number of epithelial crescents. According to the mode of development and time of onset of renal failure, these 13 patients could be divided into three sub-groups: (1) early renal failure without oliguria (three patients), (2) early renal failure with severe oliguria or anuria (three patients) and (3) delayed renal failure (seven patients).Although there are exceptions, the development of renal insufficiency in an adult patient suffering from acute glomerulonephritis is usually associated with a guarded prognosis. 相似文献
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