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Agricultural drainage ditches help remove excess water from fields and provide habitat for wildlife. Drainage ditch management, which includes various forms of vegetation clearing and sediment dredging, can variably affect the ecological function of these systems. To determine whether ditch conditions following dredging/vegetation clearing management affected the survival, growth, and development of embryos and tadpoles of northern leopard frogs (Lithobates pipiens), we conducted three field studies using in situ cages over 2 years. We measured nutrients, pesticides, and other water quality properties in vegetated/unmanaged (i.e., no clearing or dredging) and newly cleared/dredged (i.e., treeless, then dredged), clay-bottomed drainage ditches in a river basin in Eastern Ontario, Canada. Nutrients, atrazine, and total neonicotinoid concentrations were generally lower at the cleared/dredged sites, whereas glyphosate was at higher concentrations. In contrast, water-quality variables measured in situ, particularly temperature, dissolved oxygen, and turbidity, tended to be higher in the cleared/dredged sites. Total phosphorous and total organic carbon concentrations at all sites were above the recommended limits for amphibian assays. No significant differences were detected in the survival, hatching success, or development of embryos among the ditch management treatments, but premature hatching was observed at one vegetated/unmanaged site where high specific conductivity may have been formative. We found the cleared/dredged sites supported earlier tadpole growth and development, likely as a result of the higher water temperatures. Increased temperature may have offset other growth/development stressors, such as those related to water chemistry. However, the long-term consequences of these differences on amphibian populations requires further study.

Bacillus strains are known to produce cyclic lipopeptides that are capable of providing protection against plant pathogens. Such abilities could be utilized to protect greenhouse tomatoes against diseases including bacterial canker caused by Clavibacter michiganensis subsp. michiganensis (Cmm). In the present study, Bacillus velezensis strain 1B-23 and Bacillus sp. strain 1D-12 were assessed for their potential biocontrol abilities against Cmm strain 98–1 (Cmm98–1). Both Bacillus strains interfered with growth of Cmm98–1 in vitro, as determined by agar plate assays to screen for microbial antagonism. Inoculation of Cmm98–1 infected tomato plants with B. velezenis 1B-23 or Bacillus sp. 1D-12 lead to significantly reduced disease incidence in a greenhouse setting. Liquid Chromatography coupled to Mass Spectrometry (LC-MS) of 1B-23 and 1D-12 extracts identified [Leu7]surfactin C13 (often called surfactin A), [Leu7]surfactin C14 (often called surfactin B) and [Leu7]surfactin C15 (often called surfactin C) in fractions of extracts that inhibited growth of Cmm98–1.

Wood waste from forestry practices offers an inexpensive source of biomass that can be converted into bioenergy, fuels and value-added chemicals. Balsam fir (Abies balsamea (L.) Mill.) bark offers a source of bioactive natural products, such as lignans, separated through solvent extraction (SE). The objectives of the research were: (1) to compare traditional solvent with supercritical fluid extraction (SFE) and slow pyrolysis processes to separate and convert chemicals from the bark and (2) to assess the biological activity of the extracts and pyrolysis oils. In vitro biochemical assays were used to measure antioxidant and oxygen radical-scavenging abilities, and glutathione S-transferase and esterase enzyme inhibition. The pyrolysis oil had similar anti-oxidant, radical-scavenging ability and enzyme inhibitory activity to the SE and SFE extracts. Fractionation and mass spectrometry identified catechol and p-coumaryl alcohol in the organic phase of pyrolysis oil. The small phenolic compounds identified offer starting materials for pharmaceutical or insecticide synergist application.

This is the first report on the fecundity in adults of two nonparasitic lamprey species at risk, the Vulnerable Kern Brook Lamprey, Lampetra hubbsi and the Critically Endangered Macedonia Brook Lamprey, Eudontomyzon hellenicus. The mean absolute fecundity of L. hubbsi was 1865 eggs and that of E. hellenicus was 994. The higher fecundity in L. hubbsi was directly related to its higher mean gonadal mass (0.90 g) relative to that in E. hellenicus (0.52 g). Based on preserved museum material possessing well-developed primary and secondary sexual characters, the spawning period for L. hubbsi was inferred to be February-March and for E. hellenicus to either extend from January to May or to occur as separate events; one in January and the other in May. Because metamorphosing ammocoetes of E. hellenicus have been collected in October and in January, it is hypothesized that those metamorphosing in October spawn in January and those metamorphosing in January spawn in May. These periods need to be corroborated with field observations. Evidence for E. hellenicus spawning in January is based on the presence of spent females of this species collected in that month.

There are 38 species of living lampreys, 18 parasitic and 20 nonparasitic. The parasitic species feed as adults, while the nonparasitic do not. The taxonomy and systematics of the living lampreys is based primarily on dentition characters. Since the number of oral fimbriae and oral papillae have never been systematically investigated in lampreys, we compared them in 17 of the 18 parasitic lampreys to assess their usefulness as taxonomic characters. Both showed little variation with total length and sex within a species, while exhibiting greater variation between species. Parasitic species belonging to the three lamprey families could be distinguished using the number of oral fimbriae: southern hemisphere Mordaciidae (0) and Geotriidae (55–65) and northern hemisphere Petromyzontidae (81–144). However, the taxonomic usefulness of the two characters at the species level was limited. Ten out of the 17 species of parasitic lampreys were placed into four distinct groups based on their numbers of oral fimbriae, and only in two of these was the character diagnostic. Twelve out of the 17 species were placed into two distinct groups based on their numbers of oral papillae and for none of these was the character diagnostic. Blood feeders and intermediate feeders (blood + flesh) were shown to have significantly higher numbers of oral fimbriae than flesh feeders. The higher numbers of oral fimbriae in the former two types of feeders were presumed to be linked to their greater need to create a good seal for feeding purposes. Blood feeders were also shown to have significantly higher numbers of oral papillae than either intermediates or flesh feeders. The higher numbers of oral papillae in the blood feeders were presumed to be linked to their greater need to find suitable attachment sites for feeding purposes.

A new species of tongue sole,Paraplagusia longirostris, is described from 59 specimens (83.0– 276.2 mm SL) collected off the northern coast of Australia and southern coast of Papua New Guinea.P. longirostris is easily distinguishable from otherParaplagusia by its long, obtusely pointed snout and its high counts for dorsal and anal fin rays, caudal vertebrae and mid-lateral line scales.

CONFUSIONAL STATE IN ICU PATIENTS AFTER. WEANING FROM MECHANICAL VENTILATION AND SEDATION. F Pochard, JJ Lanore, M Belghith, JP Mira, B Renaud, F Bellivier, I Hamy, JF Vax; laire, F Brunet, JF Dhainaut. Confusional state (CS) is known to be frequent in ICU pts. It can result in a poorer prognosis at time of weaning from mechanical ventilation (MV). The aim of this study was to prospectively assess the incidence of CS in pts requiring MV and sedation during more than 24 hours, at time of weaning. Thirty-three survivor pts, Age 48.3, SAPS 15.4, OSF 1.7, OMEGA score 34a, were consecutively included. Reason for admission to ICU was acute lung injury (20), cardiac failure (5), septic shock (3), other (5). Length of MV was 17 days. Pharmacological agents used were flunitrazepam for narcose (33 pts, 35 mg/d, 11 d) and phenoperidine for analgesia (30 pts, 39 mg/d, 12 d). Neither pt had psychosis previous history, nor neurological disease. Fourteen pts suffered CS, defined as the onset of at least 2 of the following signs: disorientation, anxiety, auditory or visual hallucinations, agitation, clouding of consciousness, incoherence, perceptive disturbances, sleep disorders, after weaning from MV. No CS appeared in the 10 pts who had sedation during less than 5 days; in the other23 pts, incidence of CS was 64 % (p < .001). No metabolic etiology was found. The incidence of CS is high in ICU patients when weaning from MV and sedation; this incidence increases with the duration of MV. It should be treated with neuroleptics drugs. Further studies should be performed, in order to consider prevention of CS.

Study of 314 specimens of Rhinichthys cataractae from British Columbia, Alberta, and Wyoming, lead to the following conclusions: (1) Rhinichthys cataractae smithi Nichols,1916, is a valid subspecies, endemic to Cave and Basin Hotsprings and distinguished by 48–58 as opposed to 58–74 lateral line scales; (2) between 1925 and 1971, R. c. smithi hybridized with the eastern subspecies R. c. cataractae (Valenciennes,1842) from the Bow River and by 1981 the former had undergone almost complete introgression and was virtually extinct; (3) probable factors leading to this are introduction of tropical fishes into the hotsprings and periodic reduction of inflow from the hotsprings; (4) the closest relative of R. c. smithi is R. c. cataractae, rather than the westslope longnose dace (without a scientific name) inhabiting the Pacific basin; (5) the low number of lateral line scales of R. c. smithi may be a pleomeristic response to dwarfing; (6) R. c. smithi develops breeding tubercles at sizes as small as 21.1 mm SL, whereas R. c. cataractae develop them at 36.3 mm SL in Alberta; (7) introductions should not be made into a body of water prior to the study of its native fishes and consultation with experts in taxonomy and distribution of rare fishes. R. c. smithi is illustrated for the first time.

Bei drei Patienten mit akuter Wismutenzephalopathie und einem Patienten mit chronischer Quecksilberenzephalopathie wurden die Monoaminmetaboliten Homovanillinsaure (HVS) und 5-Hydroxy-Indolessigsaure (5-HIES) sowie die zyklischen Nukleotide cAMP und cGMP im Liquor cerebrospinalis vor und nach Probenecid-Belastung bestimmt. Bei den Patienten mit Wismutenzephalopathie ergaben sich Hinweise auf Anderungen des Dopamin und des cGMP-Stoffwechsels in Korrelation zum klinischen Schweregrad. Der Anstieg von HVS und von cGMP war im akuten Stadium der schweren Hyposomnie gehemmt und bei einem Patienten in der Ruckbildungsphase vermehrt. Bei dem Patienten mit chronischer Hg-Vergiftung war die Akkumulation von HVS fast vollig aufgehoben bei vermehrtem Anstieg von cGMP. Keine eindeutigen Anderungen waren im Verhalten des Serotoninmetaboliten 5-HIES und des cAMP erkennbar. Es wird geschlossen, das bei Wismut und Quecksilberenzephalopathie der Stoffwechsel von Dopamin und von cGMP im Hirnstamm und im Kleinhirn gestort ist.

Dopamine beta hydroxylase (DBH), The noradrenaline-synthesizing enzyme, and phenyl-ethanolamine-N-methyltransferase (PNMT), the adrenaline-synthesizing enzyme, were assayed in 18 areas of brain stem in eight cases of parkinsonian syndromes and of four age- and postmortem delay-matched controls. Dissection was performed by the "punch" technique and enzyme activities assayed by radiometric methods. No significant change was found for PNMT activity. DBH activity was significantly increased in the A2-C2 area of the medulla oblongata (including the nucleus tractus solitarius) in the cases of Parkinson's disease. The A2-C2 area is known to be implicated in the control of blood pressure in rats. These findings are discussed in relation to orthostatic hypotension and the influence of L-dopa therapy.