STUDIES IN THE VARIABILITY OF TUBERCLE BACILLI: I. A RAPID-GROWING BOVINE TYPE

1931 ◽  
Vol 4 (4) ◽  
pp. 389-398 ◽  
Author(s):  
Guilford B. Reed ◽  
Christine E. Rice
Keyword(s):  
Related Species ◽  
Tubercle Bacillus ◽  
Solid Media ◽  
Fluid Media ◽  
Acid Fluid ◽  
Bovine Type

Variability studies have been carried out on a considerable series of cultures of tubercle bacilli and related species of acid-fast bacteria. The present paper deals with a rapid-growing strain of the bovine tubercle bacillus. The results are in conformity with claims recently made by Petroff that certain types of tubercle bacilli undergo dissociation.It is shown that this avirulent, rapid-growing strain consists of R types which appear to be stable in acid fluid media and more or less stable on solid media. Rapid transfers through strongly alkaline fluids or growth in large volumes of similar media result in appreciable dissociation into S types. The S types were unstable, particularly in acid fluid media, and readily reverted to the R form.

Acoustic Band Gap Extension in One-Dimensional Solid/Fluid Phononic Crystal Heterostructure

2014 ◽  
Vol 22 (04) ◽  
pp. 1450010 ◽  
Author(s):  
Xu Yang Xiao ◽  
Run Ping Chen
Keyword(s):  
Band Gap ◽  
Phononic Crystal ◽  
Low Frequency ◽  
Wide Band ◽  
Normal Incidence ◽  
Wide Band Gap ◽  
Longitudinal Waves ◽  
One Dimensional ◽  
Solid Media ◽  
Fluid Media

The propagation of elastic longitudinal waves in one-dimensional (1D) phononic crystals (PNCs) consisting of alternating solid and fluid media is comprehensively analyzed in theory. We demonstrate the acoustic band gap (ABG) structure determined by the dispersion relation for longitudinal waves at normal incidence. According to the band structure, we design a sub-PNC by setting a reasonable thickness ratio of fluid and solid media, and then form a phononic heterostructure by merging this PNC and other PNC designed in advance. We have shown that the wide band gap exists in such a phononic heterostructure for elastic longitudinal waves at normal incidence. For oblique incidence, the wide band gap shifts towards high frequency regions, meanwhile a low-frequency band gap is split.

STUDIES IN THE VARIABILITY OF TUBERCLE BACILLI.: II. CORRELATION OF COLONY STRUCTURE, ACID AGGLUTINATION AND VIRULENCE

1931 ◽  
Vol 5 (1) ◽  
pp. 111-121 ◽  
Author(s):  
Guilford B. Reed ◽  
Christine E. Rice
Keyword(s):  
Colony Structure ◽  
Colony Form ◽  
High Acidity ◽  
Solid Media ◽  
Fluid Media ◽  
High Virulence ◽  
History Of ◽  
Highly Virulent

Twenty-eight cultures of tubercle bacilli including human, bovine and avian forms from widely differing sources have been compared as to colony structure, habit of growth in fluid media, acid agglutination and virulence for animals.It was found that the recently isolated highly virulent cultures and all the cultures with a long history of high virulence grew on solid media in S colony form; on fluid media, in the case of bovine and human types, as a continuous veil-like pellicle, in the avian types as a diffuse suspension; all were agglutinated only at a high acidity. All the a virulent or low virulent cultures or those with a history of loss of virulence now grow on solid media in R colonies; in fluid media as a heavy pellicle tending to separate into discrete islands; and are agglutinated at a relatively low acidity.

scholarly journals Non-pulmonary tuberculosis in England and in Wales. Account of a group investigation undertaken during the years 1943 to 1954

1949 ◽  
Vol 47 (4) ◽  
pp. 337-359 ◽  
Keyword(s):  
Pulmonary Tuberculosis ◽  
Relative Frequency ◽  
Tubercle Bacillus ◽  
Human Type ◽  
Laboratory Workers ◽  
Bovine Type

1. The present inquiry was designed to provide information on the relative frequency of infection in non-pulmonary tuberculosis with the human and bovine type of tubercle bacillus throughout the whole of England. A total of 149 pathologists at 120 collecting centres and 32 bacteriologists at 27 typing centres took part in the scheme. Two questionnaires relating to each patient were used, one to be filled in by the laboratory workers and one by the Tuberculosis Officer or other responsible official.1. Tubercle bacilli were isolated and typed from 112 patients in Wales. of these strains, 19 or 17·0 % belonged to the bovine and 93 or 83 % to the human type (Table 16).

TYPES OF TUBERCLE BACILLI IN HUMAN TUBERCULOSIS

1932 ◽  
Vol 7 (6) ◽  
pp. 606-616
Author(s):  
R. M. Price
Keyword(s):  
Bovine Tuberculosis ◽  
Tubercle Bacillus ◽  
Adult Group ◽  
Human Type ◽  
Group 6 ◽  
Bovine Type

Four hundred and thirty-six cases of clinical tuberculosis were investigated with a view to ascertaining the types of the infecting organism. In this series of cases, 268 were children under 14 years of age, and 168 adults, 15 years and over. Both medical and surgical cases were studied. In the juvenile group, 230 patients proved to be infected with the human type, and 38, or 14.1%, with the bovine type of the tubercle bacillus. In the adult group 6, or 3.5%, proved to be infected with the bovine type, the remaining 162 cases with the human type of the tubercle bacillus. Bovine tuberculosis in man is milk-borne and preventable.

scholarly journals THE VASELINE TUBE AND SYRINGE METHOD OF MICRO GAS ANALYSIS OF BACTERIAL CULTURES

1922 ◽  
Vol 35 (5) ◽  
pp. 667-684
Author(s):  
J. Howard Brown
Keyword(s):  
Closed System ◽  
Gas Production ◽  
Gas Analysis ◽  
Small Samples ◽  
Co2 Production ◽  
Bacterial Cultures ◽  
Solid Media ◽  
Fluid Media ◽  
Tuberculin Syringe ◽  
Constant Quantity

There has been described the use of the vaseline tube and the tuberculin syringe for the study of gas production by bacteria. A comparison is made of some of the results obtained by the use of the method here described, the Smith fermentation tube, and the tube of Eldredge and Rogers. The reports of CO2 production by certain streptococci by Ayers, Rupp, and Mudge and by Bacterium typhosus by Nichols have been confirmed by the author's method. The data presented serve to illustrate the accuracy and technical possibilities of the method. In addition to economy of glassware, medium, and labor, the vaseline tube and syringe method of micro gas analysis possesses the following advantages. (1) Gas produced above either liquid or solid media may be measured and analyzed. (2) The gas produced may be measured in terms of a definite and constant quantity of medium used. (3) The vaseline tube provides a closed system from which gases do not escape into the air. (4) Separate determinations of the CO2 produced in and above fluid media may be made. (5) Determinations may be made from very small samples of material. (6) Numerous gas analyses of the same culture may be made at various times during the growth of the culture without contaminating or destroying it. (7) Gas production may be observed under both anaerobic and controlled aerobic conditions.

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