The stimulation of pigment production byTrichophyton rubrumon a new medium

Infiltration of pale colored cranberries with gibberellic acid (10−4M, 10−5M), malathion (0.38 × 10−4M), indoleacetic acid (10−6M) and galactose (10−2M) stimulated the development of anthocyanin pigment. Galactose (0.5 × 10−1M, 0.25 × 10−1M) and sucrose (10−1M, 0.5 × 10−1M, 0.25 × 10−1M) inhibited pigment production. The experimental berries all had much lower total pigment contents than well colored, vine-ripened berries. The ratios of the four main pigments were also different. The stimulation of pigment production was not great enough to influence consumer acceptance. However, the results were sufficiently encouraging to suggest that further experiments were justified.

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23. Rusty Spot in Cheddar and other Cheese. III

Journal of Dairy Research ◽

10.1017/s0022029900000261 ◽

1931 ◽

Vol 2 (2) ◽

pp. 190-202 ◽

Cited By ~ 8

Author(s):

A. T. R. Mattick ◽

J. G. Davis ◽

D. V. Dearden

Keyword(s):

Pigment Production ◽

Hydrogen Ion ◽

Ion Concentration ◽

Hydrogen Ion Concentration ◽

Cheese Making ◽

Reduction Potentials ◽

Oxidation Reduction ◽

Stimulation Of

Summary1. The most important factor in the growth of the red spot organism in milk is the presence and growth of certain other bacteria. The reason for this is discussed.2. The bacteria most active in metabiotic stimulation of pigment production are those inducing low oxidation-reduction potentials in milk.3. The influence of factors such as variations in the method of manufacture and the composition of the milk and curd on the incidence of the fault have been investigated under practical cheese-making conditions.4. There is no correlation between the hydrogen-ion concentration and other properties of the ripe cheese and the extent of the red spot.5. Measures for the control of red spot have been suggested.

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Effects of 5-5'-Diphenyl-2-thiohydantoin (DPTH) and Thyroxine on the Ultrastructure and Chemical Composition of Rat Liver

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100066917 ◽

1971 ◽

Vol 29 ◽

pp. 570-571

Author(s):

E. A. Elfont ◽

R. B. Tobin ◽

D. G. Colton ◽

M. A. Mehlman

Keyword(s):

Chemical Composition ◽

Rat Liver ◽

Future Study ◽

Mode Of Action ◽

Liver Mitochondria ◽

Rat Liver Mitochondria ◽

Effective Inhibitor ◽

Biochemical Effects ◽

Glycerophosphate Dehydrogenase ◽

Stimulation Of

Summary5,-5'-diphenyl-2-thiohydantoin (DPTH) is an effective inhibitor of thyroxine (T4) stimulation of α-glycerophosphate dehydrogenase in rat liver mitochondria. Because this finding indicated a possible tool for future study of the mode of action of thyroxine, the ultrastructural and biochemical effects of DPTH and/or thyroxine on rat liver mere investigated.Rats were fed either standard or DPTH (0.06%) diet for 30 days before T4 (250 ug/kg/day) was injected. Injection of T4 occurred daily for 10 days prior to sacrifice. After removal of the liver and kidneys, part of the tissue was frozen at -50°C for later biocheailcal analyses, while the rest was prefixed in buffered 3.5X glutaraldehyde (390 mOs) and post-fixed in buffered 1Z OsO4 (376 mOs). Tissues were embedded in Araldlte 502 and the sections examined in a Zeiss EM 9S.Hepatocytes from hyperthyroid rats (Fig. 2) demonstrated enlarged and more numerous mitochondria than those of controls (Fig. 1). Glycogen was almost totally absent from the cytoplasm of the T4-treated rats.

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Gap junctions in the prothoracic glands of the tobacco hornworm, Manduca sexta

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100123933 ◽

1992 ◽

Vol 50 (1) ◽

pp. 706-707

Author(s):

Ji-da Dai ◽

M. Joseph Costello ◽

Lawrence I. Gilbert

Keyword(s):

Gap Junctions ◽

Small Molecules ◽

Manduca Sexta ◽

Freeze Fracture ◽

Cell Communication ◽

Cellular Level ◽

Thin Sections ◽

Prothoracic Glands ◽

Polyhydroxylated Steroids ◽

Stimulation Of

Insect molting and metamorphosis are elicited by a class of polyhydroxylated steroids, ecdysteroids, that originate in the prothoracic glands (PGs). Prothoracicotropic hormone stimulation of steroidogenesis by the PGs at the cellular level involves both calcium and cAMP. Cell-to-cell communication mediated by gap junctions may play a key role in regulating signal transduction by controlling the transmission of small molecules and ions between adjacent cells. This is the first report of gap junctions in the PGs, the evidence obtained by means of SEM, thin sections and freeze-fracture replicas.

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