Chemical compostition of the preen gland secretions from some ciconiiform birds

The preen waxes from four Ciconiiformes species are shown to be ester waxes of very different composition. Three species possess monoester waxes with branched wax acids and alcohols. In one of these waxes, homologous series of ethyl-substituted constituents are observed. In contrast to this, the uropygial gland secretion of the marabou is a triglyceride mixture.

Hydrocarbon and multibranched ester waxes from the uropygial gland secretion of grebes (Podicipediformes)

The uropygial gland secretion of some grebes (Podicipediformes) had been shown to contain saturated and unsaturated aliphatic hydrocarbons and monoester waxes. While ester waxes are common constituents of preen gland secretions, nonisoprenoid hydrocarbons have not been detected hitherto. The wax constituents are very complex, belonging to several multibranched homologous series, including unusual acids with ethyl branches. The waxes were identified by gas-liquid chromatography-mass spectrometry and equivalent chain length comparisons. A method for the prediction of equivalent chain length values of unknown methyl esters is offered. The results are discussed from a chemotaxonomic viewpoint.

Composition of the ventral gland-pad sebum from the Mongolian gerbil, Meriones unguiculatus

The chemical composition of the gland-pad sebum of gerbils of both sexes is analysed using gas-liquid chromatographical and mass spectroscopical techniques and compared with the lipids from distal skin areas. Cholesterol esters, with (omega-1)-methyl-substituted fatty acids as acidic constituents, were shown to occur in the gland-pad sebum of both sexes in high concentrations, whereas cholesta-3,5-diene could be detected in the males only.

[5-hydroxytryptamine-sensitive adenylate cyclase activity in brain synaptosomal membrane preparations]

A serotonine-sensitive adenylate cyclase system has been observed in horse brain membrane preparations. In crude mitochondrial fraction two types of activation sites were characterized, the Ka being = 2 nM and 1 micrometer. In purified synaptosomal membranes, a single adenylate cyclase activation was observed corresponding to the highest apparent affinity (KD = 2nM). This activation site might be related to the high affinity binding site (KD = 2NM) were previously described in the same membrane preparations.

Recent findings in oogenesis of Drosophila melanogaster

The role played by the vitellogenic oocytes of Drosophila melanogaster in relation to the elaboration of material taken from the haemolymph is examined by ultrastructural cytochemistry.

As revealed by the Gomori procedure, acid phosphatase occurs widely over the forming yolk platelets of the cortical and central ooplasm. A number of Golgi apparatuses in thecortical ooplasm are also positively stained with lead precipitates.

With the proceeding of the ovarian development it becomes progressively more difficult to demonstrate cytochemically the enzyme over the yolk platelets. In stage 9–10 chambers the acid phosphatase is restricted to the so-called associated body, while the rest of the yolk platelet appears devoid of lead deposits.

By using a osmium zinc iodide (OZ1) complex as a preferential staining method for the Golgi apparatus, it has been shown that, apart from the apparatus itself, a number of OZI deposits occur over the superficial layer of the forming yolk platelets. When mature yolk platelets are formed at later stages, the OZI deposits in the yolk platelets come to be restricted to the cap-like region of the superficial layer which contains the associated body.

In vitellogenic oocytes, both the internal lining of the limiting membrane of the forming yolk platelets and the associated body of the mature yolk platelets react positively, to cytochemical methods to demonstrate carbohydrates.

The present findings are interpreted as indicating the involvement of lysosomal enzymes in the process of maturation of the yolk material. The suggestion is also made that such an involvement is required to accomplish a selective hydrolysis of those blood proteins which have been taken in by vitellogenic oocytes along with yolk precursors.

Recent findings on oogenesis of Drosophila melanogaster

Vitellogenic ovaries from Drosophila melanogaster flies have been exposed, either in in vivo or in vitro conditions, to various extracellular tracers in an attempt to determine the possible route of entry of the yolk precursors.

Ruthenium red and lanthanum nitrate have been shown to gain access to the oocyte surface by initially passing through the intercellular spaces of the follicle layer. Both these tracers, however, never attain an intracellular location within any of the cells forming the ovarian chamber.

Colloidal Thorotrast when injected into adult females has never been detected within any of the ovarian chambers examined, irrespective of their stage.

Vitellogenic oocytes exposed to peroxidase in in vivo conditions exhibit the oolemma and all the structural elements present in the cortical ooplasm well labelled within a very short time after the injection. Moreover, with gradually increasing exposure times to peroxidase, the labelled yolk platelets increase progressively in number. At each time interval after the injection, the label over the yolk platelets remains restricted to the superficial layer and never gets into the associated body.

The pattern of tritiated lysine incorporation into vitellogenic oocytes has been studied over a period of 20 h. A few hours after injection of the radioactive tracer, the silver grains located over the ooplasm appear distributed at random. A predominant labelling of the yolk platelets as compared to the rest of the ooplasm, becomes evident only with a 6 h delay since the time of injection.

When analysed by electrophoresis and isolectrofocusing, the vitellogenic ovary is seen to exhibit a number of protein bands which are common to those of other tissues as, for instance, haemolymph and fat body.

The evidence obtained in the present study is discussed in relation to the hypothesis of an extraovarian origin of the yolk precursors and their sequestration into forming yolk platelets.

Recent findings on oogenesis of Drosophila melanogaster

The ultrastructure of the developing ooplasm has been examined in 2–3–day-old flies of Drosophila melanogaster with a view to clarifying the origin of the yolk platelets.

Previtellogenic ovarian chambers have been shown to exhibit a number of cytolysosomes; these are first formed in the nurse cells and are later brought to the ooplasm after having passed through the ring canals.

Just prior to the beginning of vitellogenesis some of the cytolysosomes in the ooplasm acquire in places a yolk-like appearance. As vitellogenesis commences, in early stage-8 chambers, the central ooplasm comes to exhibit a number of inclusions which combine in themselves features of both yolk platelets and cytolysosomes.

The onset of vitellogenesis at stage 8 is marked by the appearance of several structural entities on the plasma membrane of the oocyte. At this site, there appear a number of depressions or pits in between the microvilli. Deeper in the cortical ooplasm there are also present a number of coated vesicles and tubules. While the former exhibit a typical threelayered structure similar to that of the pits, the tubules lack the outer spiked layer.

Mature yolk platelets appear to be made up of three major components. These are a central homogeneous dense body, an outer superficial layer with a number of small spherules and a rounded body therein, and an external limiting membrane.

Instances of fusion between vesicles of sizes progressively larger have been observed with frequency. This observation is discussed in relation to the formation of yolk platelets by means of pinocytotic uptake. A contribution made by the nurse cells to the formation of the yolk platelets is also taken into account.

[High affinity binding of 5-hydroxytryptamine to some membrane preparations from cattle brain. Relationship to lysergic acid diethylamide (LSD)]

5 hydroxytryptamine binds to crude brain membrane preparations with two different affinities (KD = 1 to 2 X 10(-9) M for the highest, 1 to 2 X 10(-8) M for the lowest). LSD also binds with two affinities (KD = 3 to 4 X 10(-9) M and KD = 2 to 3 X 10(-8) M). Subcellular distribution of these sites shows that binding involves the two binding affinities in microsomal membranes but solely the high affinity binding sites are present in purified synaptosomal membranes. High affinity sites for 5 HT and for LSD are different as no direct competitive inhibition is observed in that case. On microsomal membranes, direct relationship occurs between low affinity binding for 5 HT and high affinity binding for LSD.

Bacterial meningitis. Limitations of repeated lumbar puncture

A retrospective chart review of 47 pateints with bacterial meningitis was conducted with respect to current guidelines used to define an adequate duration of antimicrobial therapy. Fifty percent (19/38) of patients had an inadequate response to therapy as defined by repeated lumbar puncture (LP) findings (ie, a cerebrospinal fluid (CSF) blood cell count greater than 50/cu mm and/or a CSF glucose value less than 45 mg/100 ml) at the end of therapy. No cases of relapse were seen. Persistent CSF abnormalities were not associated with the presence of complicating disease but were associated with prolongation of antimicrobial therapy beyond 13 days. Patients having persistent CSF abnormalities at the time antibiotics were stopped had a higher CSF blood cell count and a lower glucose value on initial lumbar puncture than those not having persistent abnormalities (P less than .001). These results emphasize the limitations of the role of repeated LP in defining an adequate duration of antimicrobial therapy.

Diester waxes containing 2-hydroxy fatty acids from the uropygial gland secretion of the white stork (Ciconia ciconia)

The uropygial gland of the white stork secrets mono- and diester waxes as well as triglycerides, all of which contain unbranched medium chain fatty acids. n-Decanol and n-dodecanol have been the only alcohols detected in both types of waxes. The diester waxes contain 2-hydroxy fatty acids.

The permeability to cytochalasin B of the new unpigmented surface in the first cleavage furrow of the newt's egg

Two of 10 mug/ml cytochalasin B (CB) caused retraction of the first cleavage furrow in Triturus eggs, a spreading of the unpigmented surface from the furrow region and a flattening of the whole egg. CB appears to act against the contractility of the microfilamentous band at mid-cleavage so as to relax the furrow and also to weaken unpigmented surface to allow the egg to flatten. Uncleaved eggs and the initial formation of the cleavage groove were unaffected by CB. A fully-retracted first cleavage furrow reformed itself on transfer of the egg to normal medium but only at the time of second cleavage. Initiation of second cleavage depended upon there being sufficient of the original pigmented surface on the animal hemisphere. Tritium-labelled CB of high specific activty was prepared and used to study its ability to penetrate the surface of newt eggs during cleavage. Scintillation couting of whole eggs showed that CB was not taken into the newt egg until mid-cleavage (about 17 min after the double stripe stage) when new surface began to spread in the cleavage furrow. Fixation in glutaraldehyde and osmium tetroxide retained radioactivity in the egg, but more CB was retained after fixation in osmium tetroxide alone than after double fixation. Most of the retained radioactivity was in yolk platelets. Autoradiographs were prepared to sectioned eggs which had been fixed at late cleavage after [3H]CB had flattend the furrow. These showed that CB entered the egg through the unpigmented surface which formed in the furrow but it could not enter through the pigmented surface. The impermeability of the pigmented surface explains the observations that CB does not prevent initial furrowing at cleavage. Once inside the egg CB is transported slowly. CB penetrates to a limited extent beneath the pigmented surface from its border with the unpigmented surface in the first cleavage furrow and this seems insufficient in some circumstances to suppress the contractile phase of second cleavage.

The permeability to cytochalasin B of the new unpigmented surface in the first cleavage furrow of the newt's egg

Two to 10 µg/ml cytochalasin B (CB) caused retraction of the first cleavage furrow in Triturus eggs, a spreading of the unpigmented surface from the furrow region and a flattening of the whole egg. CB appears to act against the contractility of the microfilamentous band at mid-cleavage so as to relax the furrow and also to weaken unpigmented surface to allow the egg to flatten. Uncleaved eggs and the initial formation of the cleavage groove were unaffected by CB. A fully-retracted first cleavage furrow reformed itself on transfer of the egg to normal medium but only at the time of second cleavage. Initiation of second cleavage depended upon there being sufficient of the original pigmented surface on the animal hemisphere.

Tritium-labelled CB of high specific activity was prepared and used to study its ability to penetrate the surface of newt eggs during cleavage. Scintillation counting of whole eggs showed that CB was not taken into the newt egg until mid-cleavage (about 17 min after the double stripe stage) when new surface began to spread in the cleavage furrow. Fixation in glutaraldehyde and osmium tetroxide retained radioactivity in the egg, but more CB was retained after fixation in osmium tetroxide alone than after double fixation. Most of the retained radioactivity was in yolk platelets. Autoradiographs were prepared of sectioned eggs whichad been fixed at late cleavage after [3H]CB had flattened the furrow. These showed that CBentered the egg through the unpigmented surface which formed in the furrow but it could not enter through the pigmented surface. The impermeability of the pigmented surface explains the observations that CB does not prevent initial furrowing at cleavage. Once inside the egg CB is transported slowly. CB penetrates to a limited extent beneath the pigmented surface from its border with the unpigmented surface in the first cleavage furrow and this seems insufficient in some circumstances to suppress the contractile phase of second cleavage.

Chemical composition of the nasal gland secretions from the marsh deer Odocoileus (Dorcelaphus) dichotomus (Illiger)

The secretion of the nasal gland from the marsh deer (Odocoileus dichotomus) has shown to be a lipid mixture predominantly containing cholesterol esters, mono- and diester waxes, the latter of which containing 2-hydroxy fatty acids. The alcoholic constituents of the mono- and diester waxes contain considerable amounts of mono-unsaturated homologues, all with the double bonds in (omega-9)-position.

[Precipitation and prevention of abstinence in acutely morphinized rats and mice: comparisons between naloxone, naltrexone, and diprenorphine (author's transl)]

Abstinence signs were precipitated in rats by naloxone (1 mg - kg-1 s.c.) injected at various times (from 1.5 to 16 h) after a single dose of morphine hydrochloride (15 or 50 mg - kg-1 s.c.) administered in aqueous solution. Increasing the dose of morphine increased the latency of the phenomena and the duration of the underlying state; "shifts" of signs as described by Bläsig et al. (1974) in chronically morphinized rats also occurred when increasing the dose of morphine and the time interval between the injections of morphine and of naloxone. Naltrexone and diprenorphine were also effective. These three antagonists, given before morphine, were able to prevent precipitated abstinence: however, naloxone was almost ineffective when the higher dose of morphine was used and when the time interval was long. In these latter conditions, naltrexone was definitely more effective and longer acting and diprenorphine still more so. The same characteristics were found for the protective action of the three antagonists in acutely morphinized mice and the same order for their potencies in precipitating abstinence in acutely morphinized mice. Like naloxone, naltrexone and diprenorphine facilitated a nociceptive reaction in normal mice. The abstinence signs precipitated in acutely morphinized rats or mice are probably not unmasked excitatory effects of morphine as such effects should have been increased rather than inhibited by previous administration of specific antagonists; they might correspond to potentiated effects of the antagonists themselves. The prevention by specific antagonists of the abstinence syndrome is most simply interpreted by antagonism (direct or indirect) of dependence induction, but other interpretations are not excluded.