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Distinguishing characteristics include: - scolece divided into four distincty curled bilobed bothridia with marginal loculi, -anatomy without post vaginal tests, - lateral genital atrium always in posterior 1/4 of segments, - about 100 testes.
Progrillotia pastinacae Dollfus, 1946 (Cestoda: Trypanorhyncha) is redescribed from the spiral valve of Dasyatis pastinaca (Linnaeus) (Dasyatididae) from the coast of France. Progrillotia dasyatidis sp. n. is described from the spiral valves of Dasyatis tortonesei Capapé (Dasyatididae) from the Mediterranean in the Gulf of Gabès (Tunisia) and D. pastinaca from the Bassin d'Arcachon (France). The new species differs from congeners in having, on the tentacles, a single rather than two rows of intercalary hooks and fewer testes. The generic definition is emended based upon the new species, the redescription of P. pastinacae Dollfus, 1946 and re-examination of the type specimen of P. louiseuzeti Dollfus, 1969. Important additional characters noted are that the tentacular hooks are solid, a prebulbar organ is present and that there are gland cells attached to the retractor muscle within the bulb. A cladistic analysis suggests that the genus is closely allied with the Eutetrarhynchidae. Progrillotia dollfusi Carvajal et Rego, 1983 is provisionally excluded from the genus as the adult of the species is unknown and a key character of the genus is that the testes are pre-ovarian.
Scalithrium gen. n. (Cestoda, Tetraphyllidea) is proposed with Scalithrium minimum (Van Beneden, 1850) n. comb., parasite of Dasyatis pastinaca (Elasmobranchii, Dasyatidae) as type-species. The new genus Scalithrium (Tetraphyllidea, Phyllobothriidae, Rhinebothriinae) is erected for several species previously included in the genus Rhinebothrium. These species have a scolex with four bothridia, the distal surface of which is divided by transverse septa in a single row of loculi. Scalithrium minimum (Van Beneden, 1850) n. comb. is redescribed from specimens collected from the type-host Dasyatis pastinaca in Tunisia and becomes the type-species of the new genus. After Braun (1900) Echeneibothrium variabile Van Beneden, 1850 is considered as type-species of the genus Echeneibothrium. Species of Rhinebothriinae to be transferred into the genus Scalithrium are discussed and a key is proposed for the eight species.
Callus cultures of Pastinaca sativa L. (parsnip), Apiaceae, were cultivated on variants of Linsmaier-Skoog's medium, containing varying quantities (0.1-10.0 mg/l) of phytohormones: NAA-BAP and IBA-BAP which allowed to obtain 1.5-3-fold fresh biomass growth during 6-week subcultures. HPLC analyses showed that tissues cultured in vitro produced psoralen, bergapten, xanthotoxin, isopimpinellin and umbelliferone which are well known metabolites in plants growing under natural conditions. Total content of coumarins depended on the nature and quantity of phytohormones present in the medium, and ranged from 115.7 to 408.5 mg/100 g of the dry weight, isopimpinellin being the metabolite which dominated quantitatively (maximum content of 238.9 mg/100 g). Psoralen was also accumulated in callus tissues at considerable amounts (maximum content of 108.8 mg/100 g). This metabolite dominated in vegetative plant parts that have been analysed in our study (leaves, stems, roots) but its contents were lower than in the material from in vitro culture (48.9 mg/100 g 10.6 mg/100 g and 14.9 mg/100 g, respectively). Imperatorin was not detected in callus tissues although it dominated in the analysed fruits of the studied plant (200.0 mg/100 g). The best of the tested media in respect of promoting tissue biosynthetic capabilities was that which contained 3 mg/l NAA and 1 mg/l BAP. The studies showed that in vitro cultures of Pastinaca sativa L. can be a convenient model to study the biosynthesis of furanocoumarins and also a potential rich source of these compounds, particularly isopimpinellin.
The dependence of the phosphorylation reaction rate on the glucose-1-phosphate concentration is investigated in Dasyatis pastinaca in a wide temperature range (5-45 degrees C). In the temperature range of 20-40 degrees C nH is equal to 1.3-1.7. The disturbance of allosteric interactions of active sites with the loss of kinetic substrate cooperativity is observed at 45 degrees C. v(S)-Dependence with the intermediate plateau is obtained at 5 degrees C and high concentration of glycogen phosphorylase B (EC 2.4.1.1), that is explained by the formation of inactive tetramer. Studies in activation of glycogen phosphorylase B of Dasyatis pastinaca under the effect of glycogen phosphorylase (EC 2.7.1.38) kinase have revealed temperature-dependent changes in the pattern of kinetic curve. An assumption is advanced that the presence of the association-dissociation equilibrium in oligomeric forms of glycogen phosphorylase B with different enzymic activity and the effect of the temperature-dependent conformation state of this enzyme on the kinase reaction rate plays an essential role in regulation of glycogenolysis in the muscular tissue of ectothermal animals.
Analysis of plant material is an important task in chemotaxonomical investigations, in search of plants with pharmacological activity or in standardisation of plant drugs. The choice of optimal conditions for the analysis of plant material and effect of extraction method on the yield of furanocoumarins from Pastinaca sativa fruits were examined. The following extraction methods were used in experiments: exhaustive extraction in Soxhlet apparatus, ultrasonification (USAE) at 25 and 60 degrees C, microwave-assisted solvent extraction in open and closed system (MASE) and accelerated solvent extraction (ASE). In most cases, the yield of furanocoumarins was highest by use of ASE method as well as by ultrasonification at 60 degrees C.
Although insect herbivory has been shown to act as a selective agent on plant secondary metabolism, whether primary metabolites contribute to resistance and can respond to selection by herbivores remains untested. In the wild parsnip (Pastinaca sativa), its principal herbivore, Depressaria pastinacella, acts as a selective agent on furanocoumarin resistance factors. In this study, we determined whether webworms can, by causing differential reductions in fitness, act as selective agents on parsnip primary metabolites. Estimates of narrow-sense heritabilities were significantly different from zero for C18 fatty acids in buds and developing fruits, fructose and sorbitol in buds, fructose, myo-inositol, bergapten, and psoralen in fruits. Wild parsnips protected from webworms by insecticide produced 2.5 times as much seed biomass as unsprayed plants; that webworms accounted for this difference in plant fitness was indicated by a significant negative relationship between reproductive effort and an index of webworm damage. Only a handful of metabolites influenced resistance to webworms; these included osthol, sorbitol, and protein in developing fruits as well as previously documented furanocoumarins. Osthol, a coumarinic compound, enhanced resistance, as did protein content, while sorbitol lowered resistance. Other primary metabolites may affect resistance to webworms, but their effect was context-dependent, that is, their effect depended on concentrations of other metabolites (epistasis). Susceptible plant phenotypes were found to have average chemical compositions. Although there was genetic variation in some of the primary metabolites in parsnips, the epistatic nature of their involvement in resistance and the lack of genetic variation in some suggest that selection on them from webworms will be either inconsistent or ineffective.
Amino acid binding protein (98 kDa) from olfactory epithelium of skate, Dasyatis pastinaca, form a stable complex with the 56 kDa protein. This complex dissociates in the presence of 10 microM GTP gamma S and 2 mM MgCl2. The 56 kDa protein has a steady-state GTPase activity (15 nmol/min per mg). Binding of amino acids to the 98 kDa protein specifically stimulates GTPase activity of the 56 kDa protein; half-maximal stimulation of GTPase activity is observed at 0.1 microM amino acid.
Studies have been made on Mg2+-activated ATPase of electroreceptor structures of the lateral line organin the ray D. pastinaca. It was shown that the enzyme is activated by magnesium ions (2.5 mM), maximum activation being observed at pH 8.0-8.5. The enzyme exhibits substrate specificity to adenyl nucleotides. Walls of ampullar canals also contain Mg2+-ATPase, however the level of the enzymatic activity in these walls is significantly lower.
Roots of celery (Apium graveolens) and parsnip (Pastinaca sativa) were inoculated with Sclerotinia sclerotiorum. At the beginning of the infection it is recognized that the level of furocoumarins rises but decreasing in the further time. Trimethylpsoralene was detected neither dc nor hplc. Sclerotinia grows poorly in parsnip. In this the high level of furocoumarins prevents the growth of the fungus because the furocoumarins are fungistatic. Obvious Sclerotinia is able to stimulate the origin of furocumarins in genetic predestinated plants first at time which can explained as reaction against the infection. The infection cannot avail to arise the technical useful yield.
During adaptation of the skate Dasyatis pastinaca (L) to distilled sea water (7.1%) resulted in decreasing concentration of sodium, urea in blood serum, reduction in the chloride cells volume, their nuclei and increase of the apical part of the cell free from mitochondria (and occupied by the endoplasmic reticulum) are observed. Owing to uniformity of the morphometric changes of the chloride cells revealed in two types, during adaptation of the skate to the distilled sea water, as well as adaptation to its increased salinity, it is possible to conclude that in the gill of selachians there are chloride cells of one type with various functional activity. Adaptation of the skate to the distilled sea water is connected with removal of lipid inclusions out of the cells of the interrenal gland.
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The 25 000 x g pellet of skate and carp olfactory tissue was found to contain structures with high affinity for amino acids (Kd approximately 10(-10) M). Results from competition experiments suggest that a multiplicity of types of olfactory binding sites exists in the skate and carp. Some parameters of a possible receptor for amino acids were evaluated. The isoelectric point of these sites solubilized with Triton X-100 was 5.35 and the molecular weight was about 120 000-150 000.
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