Morphology and feeding in tadpoles of Ceratophrys cranwelli (Anura: Leptodactylidae)

This paper provides data on the skeleton, musculature, buccal apparatus, buccopharyngeal cavity and diet of Ceratophrys cranwelli tadpoles, and attempts to contribute to the knowledge of relations between morphology and ecology in anuran larvae. Both in morphological characters and feeding habits, these tadpoles are very similar to other species within the genus. They possess many of the structural features usually found in predaceous tadpoles: strong, keratinized jaw sheaths and keratodonts, reduced buccal papillation, high values of in‐lever arm proportion and buccal floor area, well‐developed ceratohyals, and hypertrophied jaw muscles. Food sources consist of other tadpoles, microcrustaceans, larvae of insects, plant fragments, as well as rotifers and microalgae. As facultative carnivores, they are likely to play an important role in regulating the aquatic communities of the ephemeral ponds where they develop.     

The induction of microsomal NADPH:cytochrome P450 and NADH:cytochrome b(5) reductases by long-term salt treatment of cotton (Gossypium hirsutum L.) and bean (Phaseolus vulgaris L.) plants.

We studied the effect of salinity on the activity of microsomal NADPH:cytochrome P450 reductase (CPR, EC 1.6.2.4) and NADH:ferricytochrome b(5) oxidoreductase (B5R, EC 1.6.2.2) in two dicotyledonous plant species differing in their sensitivity to salt, cotton (Gossypium hirsutum L. cv Ogosta) and common bean (Phaseolus vulgaris L. cv Dobrujanski 7). A significant inhibition of fresh weight of salt-treated bean plants was observed, while cotton was affected to a much lesser degree. NaCl application resulted in a significant increase in the activity of both reductases, but was more pronounced in salt-tolerant cotton. We suppose that alterations in B5R and CPR activities may be targeted to the maintenance of membrane lipids. Most probably, plants use both enzymes (B5R and CPR) and their respective electron donors (NADH and NADPH) to reduce cytochrome b(5), which can donate reducing equivalents to a series of lipid-modification reactions such as desaturation and hydroxylation.     

A study in test reproducibility between laboratories: Report of a Pseudomonas Working Party

The results are reported of a collaborative study in laboratories of 17 tests commonly used for pseudomonads, together with statistical analysis of the results in the form of analyses of variance. The studies involved 59 strains. The following tests showed good or reasonably good consistency between different laboratories: motility if checked by a Craigie tube, growth at 4 C, production of fluorescin, oxidation of glucose and sucrose, gluconate oxidation, hydrolysis of aesculin, arginine and casein, and gelatin hydrolysis by the tube method. The following were less satisfactory: shape, size and arrangement of organismis, growth at 42 C, oxidase, acid from lactose, reduction of nitrate, acetic acid from ethanol, gelatin hydrolysis by the plate method, and the egg yolk reaction. The following showed poor consistency or noticeable difficulties in performing or interpreting results of the test: growth at 37 C, the denitrification test of Stanier, Palleroni and Doudoroff, and hydrolysis of urea. However, with several of the unsatisfactory tests the replicates within a laboratory showed much better reproducibility. This (together with other evidence on the importance of exact control of variables such as temperature, and time of reading, and the occurrence of mutants in some strains) suggests that careful attention to standardization may give much better testing methods. The considerable value of statistical analyses in such work is discussed.     

Peptide alkaloids of Scutia buxifolia

Two new components, the peptide alkaloid scutianine D and scutianene C have been isolated from Scutia buxifolia and their structures elucidated. The configuration of some of the asymmetric centers of scutianine A has been determined by gas chromatography.     

„Hypophysensyndrom“ nach embryonaler Testosteronbehandlung weiblicher Meerschweinchenkeime und Schicksal der früh ausgereiften Ova

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