Miospores in middle-upper Frasnian to Famennian sediments partly dated by conodonts (Boulonnais,France)

The middle-upper part of the Formation de Beaulieu exposed in the new railroad trench at Caffiers-Ferques and the Formation de Ferques exposed in the Tartinskal quarries contain well-preserved miospore assemblages. They are here restudied in comparison with new conodont data ranging from the middle asymmeyricus to the Ancyrognathus triangularis Zone. The conodonts allow precise correlations with the type Frasnian area as well as with the Russian Platform and Timan-Pechora provinces. The miospore assemblages of the Formation d'Hydrequent are also considered and their age discussed in term of the Frasnian/Famennian boundary.In the systematic part, two new combinations are proposed: Ancyrospora lysii (Taugourdeau-Lantz, 1960) nov. comb., and Pustulatisporites rugulatus (Taugourdeau-Lantz, 1967) nov. comb.     

Comparative study of amylolytic enzymes production byAspergillus niger in liquid and solid-state cultivation

Summary Amylolytic enzymes produced by a strain ofAspergillus niger cultivated on cassava starch in liquid or solid culture were found to be mainly glucoamylases. For the same initial amount of substrate, the glucoamylase activity increased even after 60 h of culture on solid medium whereas it decreased in liquid culture. Some characteristics of the amylases produced in both culture conditions were compared. The pH optima for enzymes produced in solid and liquid cultures were 4.5 and 5.0 respectively. Glucoamylase synthetized in solid cultures was significantly more thermostable than that from liquid culture and was maximally active at 70°C compared to 50°C for the enzyme from liquid cultures. The Km values expressed as mg soluble starch/100 ml were 0.1% for crude enzyme from solid culture and 0.057% for crude enzyme from liquid culture.     

The genetic basis of C-glycosyl flavone B-ring modification in maize (Zea mays L.) silks.

Resistance to corn earworm (CEW) (Helicoverpa zea Boddie) has been attributed to high concentrations of C-glycosyl flavones and chlorogenic acid in maize (Zea mays L.) silks. The most common C-glycosyl flavones isolated from maize silks are maysin, apimaysin, and methoxymaysin, which are distinguished by their B-ring substitutions. For a better understanding of the genetic mechanisms underlying the synthesis of these compounds, we conducted a quantitative trait locus (QTL) study with two populations: (Tx501 x NC7A)F2 and (Tx501 x Mp708)F2. For chlorogenic acid, maysin, and methoxymaysin concentration, the major QTL for both populations was located on chromosome 4 near umc1963. For apimaysin, the major QTL in both populations was located at the position of the pr1 locus on chromosome 5. The QTL alleles on chromosome 4 that increased the synthesis of methoxymaysin significantly decreased the synthesis of maysin and chlorogenic acid. This decrease in maysin concentration was four-fold greater than the increase in methoxymaysin. Our results indicate that the QTL on chromosome 4, responsible for the increase in methoxymaysin synthesis, alters the dynamics of both the phenylpropanoid and flavonoid pathways.     

Effect of imazaquin on absorption, translocation, and pattern of distribution of chlormequat chloride in winter wheat

The role of imazaquin in the absorption, translocation, and distribution of chlormequat chloride in CYCOCEL^* CL has been studied in winter wheat. Three treatments were applied to the 5th leaf of the main stem at growth stage 5 (Feekes Large scale): (1)¹⁴C-chlormequat chloride, (2) CYCOCEL^* CL containing¹⁴C-chlormequat chloride, and (3) CYCOCEL^* CL containing¹⁴C-imazaquin. Tracing of the radioactivity was followed in the treated leaf, main stem, tillers, and roots. Results showed that more than 85% of the radioactivity absorbed remained in the treated leaf. Ten days after the application of chlormequat chloride alone, 94.4% of the¹⁴C-chlormequat was found in the treated leaf, 2.9% in the main stem, 1.2% in the tillers, and 1.4% in the root system versus 88.2, 8.2, 2.1, and 1.4%, respectively, for the chlormequat chloride plus imazaquin treatment. It was concluded that imazaquin increases the mobility and the pattern of distribution of chlormequat chloride in the plant.     

Calcium alginate immobilization of mammalian neurons: A potential tool to purify ligands of neuronal membrane proteins

Summary We report here improved immobilization conditions which permitted (i) to immobilize mouse neuroblastoma cells in calcium alginate beads, (ii) to test the functions of using patch clamp techniques and (iii) to quantitatively analyze ligand interactions with voltage-dependent sodium channels in neurons immobilized inside alginate beads. These results qualify this immobilization technique as a biotechnological tool to isolate and/or purify ligands of neuronal membrane proteins. A part of these results was presented at the International Symposium “Physiology of immobilized Cells” at Wageningnen, The Netherlands, December 10–13, 1989     

Biochemical research on oogenesis. Comparison between the proteins of the ribosomes and the proteins of the 42 S particles from small oocytes of Xenopus laevis

Previtellogenic oocytes of Xenopus laevis synthesize large amounts of 5 S RNA and transfer RNA, but very little, if any, 28 S and 18 S RNA. About half of the RNA of these oocytes is stored in nucleoprotein particles sedimenting at 42 S. These particles contain 5 S RNA, transfer RNA, and several proteins, the function of which remains so far unknown.The proteins of the 42 S particles were analyzed by two-dimensional electrophoresis on polyacrylamide gel. The resulting fingerprints displayed one major and two minor basic spots. None of these coincided with any of the 37 spots produced by the 60 S subunit of the ribosomes and with the 30 spots produced by the 40 S subunit. We conclude that no ribosomal component other than 5 S RNA is present in the 42 S particles.The fingerprints of 40 S and 60 S ribosomal proteins from X. laevis coincided almost completely with the corresponding fingerprints from the rat and the rabbit.     

Three new alkaloids from Buxus papillosa

Three new steroidal alkaloids have been obtained from Buxus papillosa Schneider. These are (?)-cyclobuxupaline-C (IV)(+)-cyclopapilosine-D (VII) and (+)-buxamine-C (IX). A known alkaloid also present is desoxy-16-buxidienine (X).     

Cytologic examination of post prostatic massage specimens as an aid in diagnosis of carcinoma of the prostate.

The results of cytologic examination fo post-massage prostatic secretion from symptomatic and asymptomatic subjects were evaluated by comparison with available tissue diagnosis. Specimens studied consisted of post-prostatic massage secretion and urine. The latter specimen gave much superior results. Although possibility of the cytologic diagnosis in prostatic carcinoma cases was limited, it proved to be reliable. Presently available short follow-up data indicate that this technique may play a role only as a diagnostic aid, however, its real value in prostatic cancer detection, could be only evaluated by long term follow-up of the "high risk" group.     

Release of unsaturated vitamin B12 binding capacity from human granulocytes by the calcium ionophore A23187

The ionophore A23187, in the presence of calcium ions, was capable of eliciting the release of granule-associated unsaturated vitamin B₁₂ binding capacity from human granulocytes. The ionophore-induced extrusion of unsaturated vitamin B₁₂ binding capacity was concentration, time and temperature-dependent. The release was blocked by 2-deoxyglucose and was unaccompanied by cytotoxicity (trypan-blue uptake and lactate dehydrogenase release). The unsaturated vitamin B₁₂ binding capacity release was accompanied by the release of lysozyme, a specific granule marker enzyme.