Phyllocarid remains (Malacostraca, Crustacea) from the basal Famennian (Late Devonian) of the Montagne Noire (Southern France)

From the early Famennian of the Montagne Noire 19 different morphotypes of probably phyllocarid (Crustacea) affinities are described. Apart from formerly unknown enamel-like structures that veil the uppermost tips of the denticles on most of the gnathal lobe morphs, the stratigraphic implications concerning extinction behaviour across the Kellwasser mass extinction event and during early Famennian diversification are discussed. In addition, phyllocarids in the Famennian seem to form a useful stratigraphic tool for biostratigraphical correlation. Therefore, three basal Famennian phyllocarid assemblage zones are distinguished.      

Seasonal population dynamics of Paraquimpevia tenevvima (Linstow) (Nematoda) in the European eel Anguilla anguilla (Linnaeus) in three localities of southwest England

Seasonal population dynamics of Puraquzmperia tenerrima (Linstow) in the European eel Anguillu anguillu (Linnaeus) have been investigated in three localities in Devon, southwest England. The nematode is common and exhibits very similar seasonal patterns in changes of prevalence and abundance in the three localities. The population increases over winter through to late spring or early summer as the recruitment of the new generation occurs throughout this period. Reproduction of the nematode starts in spring. A sharp decrease of prevalence and abundance accompanies or follows reproduction, and infection levels are very low in autumn and early winter. The dispersion pattern of the nematode varies with the infection levels from over-dispersion in spring and early summer to almost random dispersion in autumn and winter. It is suggested that P. tenerrimu is a common specific parasite of eels, especially in small streams or rivers and that insect larvae or species of crustaceans might serve as intermediate hosts for the nematode.     

A new chondrophorine (Cnidaria,Hydrozoa) from the cadiz formation (Middle Cambrian) of California

We describe a new species of chondrophorine hydrozoan,Palaelophacmaea valentinei sp. nov., from the early Middle Cambrian part of the Cadiz Formation of the Marble Mountains of southeastern California. This find extends the stratigraphic range of this genus into the early Middle Cambrian and its geographic range into the western United States. We review various chondrophorine-like fossils and present a tentative chondrophorine phylogeny in light of this find.     

Comparative population ecology of Ephydra hians Say (Diptera: Ephydridae) at Mono Lake (California) and Abert Lake (Oregon)

The population dynamics of Ephydra hians Say final instar larvae and pupae were compared over a two year period in rocky littoral habitats of two alkaline saline lakes in the western Great Basin. Relative abundance increased from 1983 to 1984 at Mono Lake (California), during dilution from ca. 90 to 80 g 1^-1 TDS (total dissolved solids). In contrast, relative abundance decreased over the same period at Abert Lake (Oregon), accompanied by a dilution of salinity from ca. 30 to 20 g l^-1 and a marked increase in the number and abundance of other benthic macroinvertebrate species. These observations are consistent with a hypothesis that proposes biotic interactions limit E. hians abundance at low salinity, and physiological stress limits abundance at high salinity.Oviposition extends from early spring to early fall. Mixed instars present throughout this period indicates multivoltine population dynamics with overlapping generations. The standing stock biomass of final instars increases exponentially in late spring and peaks in late summer or early fall. Pupae increase in proportional representation and abundance from a spring minimum to a fall maximum. The body size of adults and pupae cycle seasonally from a spring maximum to a fall minimum, and may be related to either or both food limitation, or water temperature.     

Gold Nanoparticle (AuNP)-Based Surface-Enhanced Raman Scattering (SERS) Probe of Leukemic Lymphocytes

Plasmonics - Identification of cellular surface marker is an effective approach in the early diagnosis of tumor. In this study, based on the finite difference time domain (FDTD) simulation, combing...     

Observation of some key stages of the embryonic development of Biomphalaria straminea (Dunker, 1848) (Molluska,Planorbidae)

Summary

Biomphalaria straminea is a freshwater snail and one of the intermediate hosts of the trematode parasite which causes schistosomiasis in Brazil. The main stages of embryonic development were analyzed with confocal laser scanning microscopy (CLSM), using the fluorescent probe DiOC and Nile Red as a vital stain in in vivo preparations. In fixed preparations nuclei were stained by the Feulgen reaction or the fluorescent DNA probe, Höechst 33342. Results obtained from the analysis of embryos at the stages of early cleavage, morula, blastula, gastrula, early trocophore and veliger showed that these stages are similar to those described for Biomphalaria glabrata and Biomphalaria tenagophila. CLSM optical sections of early trochophore showed important morphological structures such as the blastopore, stomodeum and shell gland; and in early veliger, internal organs such as the esophagus, stomach and male and female ducts were also clearly identified.     

Fossil penguin (Aves: Sphenisciformes) cranial material from the Eocene of Seymour Island (Antarctica)

Our knowledge of the cranial morphology of early penguins remains poor, particularly for Paleogene taxa. This paper describes a partial penguin skull and additional isolated cranial elements from the Eocene La Meseta Formation of Seymour Island, Antarctica. These specimens cannot be assigned to named taxa at present, but there is a strong possibility they belong to La Meseta penguins known only from postcranial elements. The skull shares extensive dorsal development of the temporal fossae with extant and fossil Spheniscus and the fossil penguins Paraptenodytes and Marplesornis, indicating the adductor complex was powerful in early penguins. Partial mandibles belonging to a much larger penguin are similar to Paraptenodytes and differ from all living penguins in the lack of a hooked medial process of the articular and the presence of a foramen anterior to the mandibular cotyles. Given the rarity of penguin cranial remains, these specimens provide important new insight into early penguin evolution.     

Life History of Ilybius fenestratus (Fabricius) (Coleoptera,Dytiscidae) in a Central Norwegian Lake

The life history of Ilybius fenestratus was studied in Målsj?en, a lake in S?r-Tr?ndelag, Central Norway (63°14'N, 10°26'E), during 1971–1972. Adults and larvae were sampled in activity traps every week during March–October and every 2–3 weeks during November–February. Newly-emerged adults were generally found from mid-July to September, and after overwintering in torpidity, probably in the water, they again appeared in the second half of June to August/September. Laying of eggs took place from early/mid July to early August. Larvae occurred in the traps from late July to early May. I. fenestratus was thus found to be a semivoltine summer breeder, with overwintering larvae the first winter and overwintering adults the next. Both adults and larvae lived in large areas of the lake's littoral zone.     

ENDOSPERM DEVELOPMENT IN THE DATE PALM (PHOENIX DACTYLIFERA) (ARECACEAE)

Date seeds were sampled at regular intervals from pollination (March) to mature fruit (September) and processed for light microscopy and SDS-PAGE. Seed fresh weight rose until early June and then declined slightly through September due to a continuous decrease in water content. Cell wall formation started in May in the free nuclear endosperm and proceeded centripetally from the inner integument to the seed center. Wall thickening in each cell started in cell corners and showed a layered appearance with calcofluor white staining. It started in early June in the center of the seed and proceeded centrifugally such that the outer cells showed cell wall thickening in late June. Thickened cell walls were soft and PAS positive at inception, but staining disappeared and hardness increased during wall maturation. Cell elongation in the radial direction accompanied wall thickening. Protein body formation started after cell wall thickening and followed the same centrifugal developmental pattern. Mature protein bodies occurred in even the outermost cells by early July. No further structural changes occurred after this time. The high molecular weight storage proteins appeared in late June, which is when protein bodies had formed in all but the outer endosperm cells; however, these proteins did not appear simultaneously and minor changes in protein bands continued until maturation. α-Galactosidase activity was present in the developing endosperm and peaked at 13 wk after pollination. The data suggest that the thickened wall is deposited as a highly substituted galactomannan, but that most of the galactose side branches are clipped off presumably by α-galactosidase during cell wall polymerization.     

Effect of (2-Chloroethyl)phosphonic Acid on Flower Induction in Juvenile Mango (Mangifera indica) Seedlings

Spray applications of 1000 mg/l (2-chloroethyl)phosphonic acid (CEPA) five times, at weekly intervals, during November and early December induced heavy flowering in ringed and nonringed juvenile mango seedlings. The treated plants produced flower buds which opened by the end of December, while the control and ringed seedlings produced only a new flush of vegetative growth. The results show that CEPA could be profitably used for early evaluation of hybrid seedlings in mango breeding programme.     

Cell cycle phase sensitivity to cis-dichloro-bis (isopropylamine) trans-dihydroxy platinum (IV) (CHIP)

Cis-dichloro-bis (isopropylamine) trans-dihydroxy platinum (IV) (CHIP) is a second generation platinum coordination complex now in Phase II clinical trials. In vitro studies with Chinese Hamster Ovary cell cultures show that CHIP is a phase-sensitive drug, being most cytotoxic to cells in early G1 phase and least toxic to late S and G2 phase cells. The dose-modifying factor between the drug sensitivity of cells treated in G1 and in late S phase is 1.6. These findings and their clinical significance are discussed with respect to the phase sensitivity of other cytotoxic agents.     

Archaeobotany of capers (Capparis) (Capparaceae)

The origins of capers, their use and cultivation are discussed. Capers seeds and charcoal are often recovered from archaeological sites of the Mediterranean and West Asia. These are referred to as C. Spinosa L. This is mostly a group of cultivars restricted to localities surrounding the Western Mediterranean and some places in the Eastern Mediterranean. Identification of the findings is discussed in terms of seed morphology, present distribution and ancient uses of C. aegyptia Lam., C. sicula Veill., C. cartilaginea Decne, C. orientalis Veill., C. decidua (Forssk.) Edgew. and other species. Citations of Capparis in early Rabbinic, Mesopotamian and Greco-Roman texts are presented. Received June 3, 2002 / Accepted October 8, 2002 Correspondence to: D. Rivera     

Comparative and experimental embryogenesis of Plectidae (Nematoda)

Comparative analysis of early embryogenesis indicates that considerable differences exist among nematode species. To better understand to what extent the well-studied development of Caenorhabditis elegans is representative for nematodes in general, we extended our earlier studies to other families of this phylum. Here we report our findings on seven species of Plectidae. We found that Plectidae embryos share a number of developmental similarities with one branch of nematodes (Secernentea), including C. elegans, but not with the other branch (Adenophorea), and thus support conclusions concerning their phylogenetic position drawn from molecular data. However, Plectidae also show developmental differences to other Secernentea, suggesting an early separation from them. Prominent characteristics of Plectidae are (1) strict left-right divisions of somatic founder cells generating a prominent early bilateral symmetry and (2) a very early start of gastrulation with immigration of a single gut precursor cell. To determine whether gastrulation with two gut precursors is crucial for C. elegans embryos, we induced it to gastrulate with a single blastomere like in Plectidae. As this alteration is compatible with an essentially normal subsequent embryogenesis, cleavage of the gut precursor before gastrulation is obviously not required. As major differences exist among nematodes concerning the potential to compensate for eliminated early blastomeres, we tested this feature in one Plectus species. We found that Plectus does not replace a lost cell but behaves like C. elegansin this respect, in contrast to our previous findings in Acrobeloides nanus, another member of the Secernentea.     

Developmental morphology of the ovules of Amborella trichopoda (Amborellaceae) and Chloranthus serratus (Chloranthaceae)

The developmental morphology of the outer integument in the pendent orthotropous ovules of Amborella trichopoda (Amborellaceae) and Chloranthus serratus (Chloranthaceae) was studied. In both species the outer integument is semiannular at an early stage and becomes cup-shaped but dorsiventrally somewhat asymmetric at later stages. The outer integument, which is initiated first on the concave and lateral sides of the ovule, differs from that of the anatropous ovules of other basal families with the outer integument semiannular at an early stage or throughout development. The bilateral symmetry of the outer integument is shared by these orthotropous and anatropous ovules. The developmental pattern of the outer integument and ovule incurving characterize the ovule of the Amborellaceae and Chloranthaceae, which is not equivalent to typical orthotropous ovules of eudicots. A phylogenetic analysis of ovule characters in basal angiosperms suggests that anatropous ovules with cup-shaped outer integuments and orthotropous ovules were derived independently in several clades and that the ovules of Amborella and Chloranthus might also be derivative.     

Drug-Induced (Thalidomide) Malformations

Phocomelia (flipper-like limbs) has long been recognized as a rare malformation. Numerous cases of phocomelia and other congenital malformations have recently been reported in the United Kingdom, Australia, Europe and Canada in which the common factor appears to have been the administration of the hypnotic compound thalidomide during early pregnancy. Two additional cases of infants born with phocomelia, amelia and alimentary abnormalities are presented. In both of these cases the administration of thalidomide was initiated early during pregnancy (five to eight weeks after the last normal menstrual period) and maintained for several weeks. Thalidomide (alpha-phthalimido glutarimide) is related chemically to other glutarimides currently in clinical use. The possibility that these compounds and/or their metabolites may induce teratogenic effects warrants consideration. Emphasis is added to the view that caution should be exercised when prescribing new drugs.     

Studies of the protein content of individualPergamasus longicornis (Berlese) (Acari: Mesostigmata: Parasitidae)

The protein content ofPergamasus longicornis (Berlese) individuals is of the order of 45 g bovine serum albumen equivalents and varies depending on gender, time of year and gut colour (postulated nutritive state). Variation between males and females closely matches their size difference. A sinusoidal relationship with a late spring/early summer maximum and a late autumn/early winter minimum is shown for females. Gut colour is a useful predictor in females only. Pregnancy and prey utilisation over the year are suggested as important determinants of protein content and are discussed in detail.     

Cell Cycle Phase Sensitivity to Cis-Dichloro-Bis (Isopropylamine) Trans-Dihydroxy Platinum (Iv) (Chip)

Abstract. Cis-dichloro-bis (isopropylamine) trans-dihydroxy platinum (IV) (CHIP) is a second generation platinum coordination complex now in Phase II clinical trials. In vitro studies with Chinese Hamster Ovary cell cultures show that CHIP is a phase-sensitive drug, being most cytotoxic to cells in early G₁ phase and least toxic to late S and G₁ phase cells. the dose-modifying factor between the drug sensitivity of cells treated in G₁ and in late S phase is 1.6. These findings and their clinical significance are discussed with respect to the phase sensitivity of other cytotoxic agents.     

Reduced Estradiol-Induced Vasodilation and Poly-(ADP-Ribose) Polymerase (PARP) Activity in the Aortas of Rats with Experimental Polycystic Ovary Syndrome (PCOS)

Polycystic ovary syndrome (PCOS) is a complex endocrine disorder characterized by hyperandrogenism and insulin resistance, both of which have been connected to atherosclerosis. Indeed, an increased risk of clinical manifestations of arterial vascular diseases has been described in PCOS. On the other hand endothelial dysfunction can be detected early on, before atherosclerosis develops. Thus we assumed that vascular dysfunction is also related directly to the hormonal imbalance rather than to its metabolic consequences. To detect early functional changes, we applied a novel rodent model of PCOS: rats were either sham operated or hyperandrogenism was achieved by implanting subcutaneous pellets of dihydrotestosterone (DHT). After ten weeks, myograph measurements were performed on isolated aortic rings. Previously we described an increased contractility to norepinephrine (NE). Here we found a reduced immediate relaxation to estradiol treatment in pre-contracted aortic rings from hyperandrogenic rats. Although the administration of vitamin D₃ along with DHT reduced responsiveness to NE, it did not restore relaxation to estradiol. Poly-(ADP-ribose) polymerase (PARP) activity was assessed by poly-ADP-ribose immunostaining. Increased PAR staining in ovaries and circulating leukocytes from DHT rats showed enhanced DNA damage, which was reduced by concomitant vitamin D₃ treatment. Surprisingly, PAR staining was reduced in both the endothelium and vascular smooth muscle cells of the aorta rings from hyperandrogenic rats. Thus in the early phase of PCOS, vascular tone is already shifted towards vasoconstriction, characterized by reduced vasorelaxation and vascular dysfunction is concomitant with altered PARP activity. Based on our findings, PARP inhibitors might have a future perspective in restoring metabolic disorders in PCOS.