VIRULENCE AND MORPHOLOGICAL CHARACTERISTICS OF MAMMALIAN TUBERCLE BACILLI

Experimental infection of the mouse can be used for the determination of virulence of cultures of mammalian tubercle bacilli. The relative virulence of such cultures for the mouse is approximately the same as for the guinea pig. Cultures of virulent and avirulent variants of mammalian tubercle bacilli grown in the depth of Tween 80-albumin liquid medium, on the surface of solid agar modifications of this medium, and on the surface of a liquid modification of this medium exhibit consistent morphological differences. All virulent cultures tend to form microscopically demonstrable serpentine cords of varying thickness and length consisting of highly acid-fast bacilli oriented in parallel along the long axis of the cord. The formation of cords appears to be an important factor in conditioning the ability of cultures to spread on the surface of liquid and solid media. It can be inhibited by the addition to the medium of the surface-active water-dispersible oleic acid ester, Tween 80. Avirulent variant bacilli grow in a more or less non-oriented fashion. They have never been observed to form cords under any condition of growth and are much less acid-fast than the virulent cultures when grown in Tween-albumin medium. Two strains of mammalian tubercle bacilli which are intermediate in degree of virulence between the fully virulent and the avirulent variants also exhibit intermediate morphological characteristics.

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THE EFFECT OF WETTING AGENTS ON THE GROWTH OF TUBERCLE BACILLI

Journal of Experimental Medicine ◽

10.1084/jem.88.1.81 ◽

1948 ◽

Vol 88 (1) ◽

pp. 81-88 ◽

Cited By ~ 41

Author(s):

René J. Dubos ◽

Gardner Middlebrook

Keyword(s):

Aqueous Media ◽

Tween 80 ◽

Unesterified Fatty Acid ◽

Sorbitan Monooleate ◽

Bacterial Surface ◽

Water Dispersible ◽

Morphological Aspects ◽

Surface Active Agents ◽

Surface Active ◽

Wetting Agents

Tween 80 and Triton A20 are two water-dispersible, non-ionic, surface-active agents which favor dispersed growth of tubercle bacilli in aqueous media probably by wetting the bacterial surface. Tween 80 is a polyoxyethylene ester of sorbitan monooleate and is liable to enzymatic hydrolysis by lipases. Triton A20 in an arylalkyl polyether of phenol which appears resistant to the known enzymes of animal tissues. Tween 80 loses its ability to disperse cultures of tubercle bacilli in media containing serum; Triton A20 does not. Tween 80 increases the yield of growth, probably by supplying oleic acid to the bacilli; Triton A20 does not. In concentrations sufficient to cause dispersed browth, Tween 80 (purified by removal of unesterified fatty acid) and Triton A20 are completely innocuous for virulent tubercle bacilli. However, Triton A20 exhibits a marked toxic effect on the avirulent variants of mammalian strains; Tween 80 does not. The two wetting agents also differ in their effects on the morphological aspects of the bacterial cultures. Whereas Triton A20 prevents the formation of large amorphous bacillary clumps, it is less effective in preventing the orientation of the virulent bacilli resulting in the formation of long bacillary strands. Tween 80 on the contrary prevents also the formation of these cords of bacilli and exerts therefore a more effective dispersing effect on cultures of virulent tubercle bacilli.

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Stability studies of mefenamic acid Self-Nanoemulsifying Drug Delivery System (SNEEDS) preparation with oleic acid as the oil phase

Jurnal Ilmiah Farmasi ◽

10.20885/jif.vol16.iss2.art5 ◽

2020 ◽

Vol 16 (2) ◽

pp. 130-143

Author(s):

Yandi Syukri ◽

Septiani Eka Cahyani ◽

Bambang Hernawan Nugroho

Keyword(s):

Oleic Acid ◽

Mefenamic Acid ◽

Tween 80 ◽

Stability Studies ◽

Storage Test ◽

Peg 400 ◽

Accelerated Storage ◽

The Stability ◽

Accelerated Storage Test

Background: Mefenamic acid is a non-steroidal anti-inflammatory drug (NSAID) with low solubility in water. Self-Nanoemulsifying Drug Delivery Systems (SNEDDS) play a role to improve the solubility and bioavailability of mefenamic acid. Objective: This study aimed to determine the stability of mefenamic acid in SNEDDS formulation through various stability studies. Methods: The stability studies conducted consisted of centrifugation test, heating-cooling cycle test, freezethaw cycle test, robustness to dilution, accelerated storage test, and determination of drug content. Results: The centrifugation test, heating-cooling cycle test, and freeze-thaw cycle test showed no phase separation in the samples. The robustness to dilution and accelerated storage test resulted in 2 formulas of mefenamic acid loaded SNEDDS having good stability with 10% oleic acid, 80% tween 80, 10% PEG 400 and 10% oleic acid, 70% tween 80, 20% PEG 400. The determination of drug content in both of these formulations showed 98.20 ± 0.04% and 90.98 ± 0.06%. Conclusion: The SNEDDS formulation of mefenamic acid in this study had good stability. Keywords: SNEDDS, mefenamic acid, stability study, oleic acid

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Determination of seasonal changes of spider mite (Acari: Tetranychidae) densities and species composition on kudzu vine and soybean (Fabaceae) in Japan with the use of phosphoglucomutase zymograms*

Zoosymposia ◽

10.11646/zoosymposia.6.1.13 ◽

2011 ◽

Vol 6 (1) ◽

pp. 72-81 ◽

Cited By ~ 1

Author(s):

TETSUO GOTOH ◽

KATSUHIKO MORI

Keyword(s):

Species Composition ◽

Spider Mite ◽

Morphological Characteristics ◽

Seasonal Fluctuation ◽

Mite Species ◽

Adult Males ◽

Glycine Max L ◽

Morphological Differences ◽

Two Peaks

Identification of spider mites based on morphological characteristics is difficult because morphological differences between species may be subtle and in some groups, including the Tetranychus Dufour species, detectable only in adult males, which usually correspond to a small proportion of a population. The utility of an alternative method, phosphoglucomutase (PGM) zymogram, is demonstrated in this study. Using this method, we were able to discriminate females of each of 13 known Japanese Tetranychus species. We examined the species composition and seasonal density changes on kudzu vine [Pueraria montana var. lobata (Willd.) Sanjappa and Pradeep], a fabaceous weed, between 1997 and 1999, and on soybean [Glycine max (L.)] between 1999 and 2001. On kudzu vine, spider mite populations showed two types of seasonal fluctuation, one characterized by a single peak in September or October and the other by two peaks, in June and September. Five spider mite species were found on this plant species, with T. pueraricola Ehara & Gotoh being dominant throughout the 3-year period and accounting for 75.6–96.9% of all females. On soybean, spider mite populations showed three types of seasonal fluctuation, characterized by one peak (August), two peaks (August, November), and three peaks (June, August, October), respectively. On this plant, eight species were found, T. pueraricola being dominant in 1999 (54.7%), T. parakanzawai Ehara in 2000 (72.6%) and T. kanzawai Kishida in 2001 (69.2%). Such annual variation in dominance was probably determined by the order of invasion of soybean fields.

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TEM processing procedure for a bacillus organism grown on solid media

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100160674 ◽

1990 ◽

Vol 48 (3) ◽

pp. 624-625

Author(s):

Jane Payne ◽

Philip Coudron

Keyword(s):

Electron Microscopy ◽

Room Temperature ◽

Fume Hood ◽

Vacuum Aspiration ◽

Solid Media ◽

Transmission Electron ◽

Solid Agar ◽

Processing Procedure ◽

Agar Media ◽

Rat Bone

This transmission electron microscopy (TEM) procedure was designed to examine a gram positive spore-forming bacillus in colony on various solid agar media with minimal artifact. Cellular morphology and organization of colonies embedded in Poly/Bed 812 resin (P/B) were studied. It is a modification of procedures used for undecalcified rat bone and Stomatococcus mucilaginosus.Cultures were fixed and processed at room temperature (RT) under a fume hood. Solutions were added with a Pasteur pipet and removed by gentle vacuum aspiration. Other equipment used is shown in Figure 3. Cultures were fixed for 17-18 h in 10-20 ml of RT 2% phosphate buffered glutaraldehyde (422 mosm/KgH2O) within 5 m after removal from the incubator. After 3 (30 m) changes in 0.15 M phosphate buffer (PB = 209-213 mosm/KgH2O, pH 7.39-7.41), colony cut-outs (CCO) were made with a scalpel.

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Gender determination of caucasoid hair using image analysis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100146928 ◽

1993 ◽

Vol 51 ◽

pp. 216-217

Author(s):

T.B. Ball ◽

W.M. Hess

Keyword(s):

Image Analysis ◽

Cross Sections ◽

Scalp Hair ◽

The Body ◽

Equivalent Diameter ◽

Cross Sectional ◽

Hair Samples ◽

Length Width ◽

Morphological Differences

It has been demonstrated that cross sections of bundles of hair can be effectively studied using image analysis. These studies can help to elucidate morphological differences of hair from one region of the body to another. The purpose of the present investigation was to use image analysis to determine whether morphological differences could be demonstrated between male and female human Caucasian terminal scalp hair.Hair samples were taken from the back of the head from 18 caucasoid males and 13 caucasoid females (Figs. 1-2). Bundles of 50 hairs were processed for cross-sectional examination and then analyzed using Prism Image Analysis software on a Macintosh llci computer. Twenty morphological parameters of size and shape were evaluated for each hair cross-section. The size parameters evaluated were area, convex area, perimeter, convex perimeter, length, breadth, fiber length, width, equivalent diameter, and inscribed radius. The shape parameters considered were formfactor, roundness, convexity, solidity, compactness, aspect ratio, elongation, curl, and fractal dimension.

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