1. Zenker's solution 4 hours at 37°C or Dominici's 3 hours.
2. 70% alcohol, 12 to 18 hours at room temperature.
3. 80% alcohol, about 5 to 6 hours.
4. 90% alcohol, about 4 to 6 hours.
5. Absolute alcohol about 16 hours.
6. Ether and absolute alcohol aa, about 8 hours.
7. 16 to 24 hours in the following mixture: celloidin 1 g., methyl salycilate 25 cc., abs. alcohol 25 cc., ether 25 cc.
8. Chloroform and paraffin, 2 to 3 hours.
10. Paraffin, 1 to 1 1/2 hours.
11. Embed.
1. Cut sections 4 to 5 μ.
2. Bring section to water and cover with Lugol's iodine for 10 minutes.
3. Decolorize with a 2% sodium thiosulfate (hypo).
4. Wash thoroly with water.
5. Cover with a mixture of equal parts of 0.5% phloxine and 1% eosin Y (National Aniline brand) and leave for 15 minutes.
6. Wash with water and stain 2 to 5 minutes in 0.1% azure B (National Aniline).
7. Wash with 96% alcohol and decolorize in a mixture of 2 parts absolute alcohol with 1 part clove oil, ordinarily for not more than 1/2 to 1 minute.
8. Dehydrate rapidly, clear, and mount in Yucatan Elemi.
l-Aspartate was found to replace l-asparagine in the protective action from acid inactivation of l-asparaginase (EC 3.5.1.1) produced by Escherichia coli A–1–3 and at the same time to inhibit the proteolytic inactivation by α-chymotrypsin.
l-Asparaginase changed in its chromatographic properties in the presence of l-aspartate and became to be absorbed on the CM Sephadex column.
The sedimentation patterns of l-asparaginase at pH 3.5 were identical either in the presence or absence of l-aspartate, showing partial dissociation. But the reversibility to the active state was observed only in the enzyme dissolved in the solution containing l-aspartate.
l-Aspartate did not prevent the enzyme either from the dissociation into subunits or from decrease in the activity by urea.
High concentration of l-aspartate was shown to inhibit the l-asparagine hydrolysis reaction.
l-Aspartate was suggested from ORD measurements to cause changes in the higher structure as well as the ionic properties or proteolytic inactivation.
- Highlights
The present investigation signifies the role of Enterobacter spp. in various processes:
??To synthesize gallic acid (a precursor for food oxidant such as propyl gallate) and a bacteriostatic antibiotic (trimethoprim).
??To protect the environment from tannery’s discharge through the process of biodegradation.
??To reduce the toxicity of tannins in animal feed.
The incorporation of 14C-methanol, 14C-formaldehyde, 14C-formate and 14C-bicarbonate into a methanol-utilizing yeast, Candida N–16, was examined by paper-chromato-graphy and radioautography.
At the earliest time period examined, the highest percentage of radioactivity fixed from 14C-methanol or 14C-formaIdehyde into methanol-grown cells was found in fructose phosphate. The percentage distribution of radioactivity in fructose phosphate decreased as time elapsed. The radioactivity fixed from these compounds into glucose-grown cells was negligible compared with that fixed into methanol-grown cells.
The incorporation of 14C-formate into methanol-grown cells was extremely low. The highest percentage of radioactivity fixed for short time incubation was found in serine. The incorporation pattern of glucose-grown cells was similar to that of methanol-grown cells.
At the earliest time period, over 70% of radioactivity fixed from 14C-bicarbonate into methanol- or glucose-grown cells was found in aspartate.
These results suggest that in Candida N–16 methanol is specifically assimilated by a route with hexose phosphate as a primary stable intermediate.
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inefficiency of the purification procedure;
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surface denaturation;
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imperfect freeze-drying of the final product; and
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factors yet unknown vhich cause alteration in the immoglobulins or other protein components not ellminated by the purification procedures.
The catalase activity of Candida tropicalis pK 233 was induced by hydrocarbons but not by glucose, galactose, ethanol, acetate or lauryl alcohol.
The induction of the catalase activity depending upon hydrocarbons was sensitive to cycloheximide but not to chloramphenicol.
Glucose repressed strongly the induction of the catalase activity by hydrocarbons but galactose did not affect seriously.
When C. tropicalis was incubated with hydrocarbons, the appearance of microbodies was observed electronmicroscopicaliy.
L-Asparaginase (EC 3.5.1.1) from Escherichia coli A–l–3 was acetylated using acetic anhydride as a modifying chemical. The fully acetylated L-asparaginase retained 60% of the activity of the unmodified L-asparaginase.
The acetylated L-asparaginase hydrolyzed D-asparagine and L-glutamine as well as L-asparagine in the same ratio as the unmodified L-asparaginase did.
However, the effects of pH on the activity of the acetylated L-asparaginase showed very interesting differences from that of L-asparaginase. On the other hand, both L-asparaginase and the acetylated L-asparaginase exhibited similar pH activity curves on L-glutamine hydrolysis.
The acetylated L-asparaginase was found to become more stable against acid or heat in the presence of L-aspartate than in its absence in the same manner as L-asparaginase was.
Fibrous substances in tobacco leaves are the main precursors of acetaldehyde, propionaldehyde, acrolein, acetone, methylethylketone, diacetyl, methanol, furan, an unknown compound, No. 6 and an unknown compound, No. 16 in cigarette smoke.
Sugars in tobacco leaves are the main precursors of 2-methylfuran and 2,5-dimethyl- furan in cigarette smoke.
Resinous substances in tobacco leaves are the main precursors of isoprene and an unknown compound, No. 2 in cigarette smoke.
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Continuous darkness leads in a few days to a disappearance of the variations of the circadian rhythms of digestive enzymes while these rhythms go on in continuous light.
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Short (1 or 2 hrs) and low intensity flashes of white light are effective in bringing on the reappearance of rhythmic variations in darkness.
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We have been able to establish an isoquantic spectrum of action of the light. Two values of wavelength appears to account for a maximum sensibility of the shrimp: one in ultraviolet light and an other one, more important, in the green (λ=544 nm).
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In green light it is possible to obtain the same effect of light by decreasing the time of stimulation to 5 or 10 mn and in increasing the total quantity of energy. Significant responses are obtained with total energy greater than 10000 pE. cm‐2.
The oxidative browning of the model systems increased with increase of the ageing period. Fe2+ increased the effects of the ageing.
The model systems aged under anaerobic conditions darkened more than those aged under aerobic conditions during storage for 2 weeks.
An Amadori rearrangement product, 1-deoxy-1-glycino-d-fructcse was isolated from the aged glucose-glycine model system and it caused a marked increase in the rate of the oxidative browning. Therefore, Amadori rearrangement products are considered to be important precursors in the oxidative browning reaction.
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Determine concernsby using risk assessment techniques for various scenarios.
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Identify the consequences by systematically identifying hazards.
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Undertake calculations by using relevant models.
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Evaluate certainties, uncertainties, and probabilities involved in the calculations of the vulnerability and of the exposure.
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Compare with criteriato assess the need for further action.
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Determine and act on options to control, mitigate, and adapt to the risk.
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Communicatethe results to those who need to know.
Summary A technic is described for demonstrating the activity of alkaline phosphatase in human leucocytes. For fixation the method ofKaplow is recommended: 90 per cent methanol +10 per cent formalin 1:10 for 30 seconds at 0°C. Other fixatives are evaluated.Under the conditions of the experiment metal ions activated the alkaline phosphatase of leucocytes in the following order: Mg++>Fe+++>Co++>Mn++>Cu++>Fe++.The effectiveness of all these metal ions was to a high degree dependent on concentration. Ni++, Zn++, and Pb++ showed an inhibitory effect also dependent on concentration.In fixed blood smears the velocity of hydrolysis of sodium--naphthylphosphate (simultaneous azo-coupling technic) is far greater than that of Na--glycerophosphate (Ca-Co-method of Gomori-Takamatsu). Adding small amounts of Fe+++ and Cu++ to the incubation medium, it is possible to increase the velocity of hydrolysis of glycerophosphate beyond the values of maximal Mg++ activation and simultaneously enhancing the initial velocity of the reaction.
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The incorporation of mevalonate-2-14C into ipomeamarone in sweet potato root tissue infected by Ceratocystis fimbriata was demonstrated, but the rate was low when compared with acetate-2-14C. No dilution effect of mevalonate was noted during the incorporation of acetate-2-14C into ipomeamarone. This is very likely to result from the passive transfer of mevalonate into the cells.
No dilution effect of acetate during the incorporation of mevalonate-2-14C into ipomeamarone was noted. This indicates that mevalonate is not incorporated into ipomeamarone after its conversion to acetate.
Evidence for incorporation of acetate-2-14C into mevalonate was shown by the fact that the specific radioactivity of mevalonic acid benzhydrylamide was not lowered throughout repetitive crystallizations. These data also support the participation of mevalonate in ipomeamarone synthesis as an intermediate.
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Identification of skulls
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Taxonomic situation of the vicugna
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Origin of the alpaca.
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l'archisporio è pluricellulare e possono svilupparis talvolta pi[ugrave] cellule madri;
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normalmente solo una cellula madre arriva a maturità;
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delle quattro megaspore solo una è fertile e precisamente la pi[ugrave] calazale;
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lo sviluppo del gametofito è del tipo Normale cioè Monomegasporiale con oangio emisporiale.