Brain cholinesterase activity of apparently normal wild birds

Organophosphorus and carbamate pesticides are potent anticholinesterase substances that have killed large numbers of wild birds of various species. Cause of death is diagnosed by demonstration of depressed brain cholinesterase (ChE) activity in combination with chemical detection of anticholinesterase residue in the affected specimen. ChE depression is determined by comparison of the affected specimen to normal ChE activity for a sample of control specimens of the same species, but timely procurement of controls is not always possible. Therefore, a reference file of normal whole brain ChE activity is provided for 48 species of wild birds from North America representing 11 orders and 23 families for use as emergency substitutes in diagnosis of anticholinesterase poisoning. The ChE values, based on 83 sets of wild control specimens from across the United States, are reproducible provided the described procedures are duplicated. Overall, whole brain ChE activity varied nearly three-fold among the 48 species represented, but it was usually similar for closely related species. However, some species were statistically separable in most families and some species of the same genus differed as much as 50%.     

Comparison of fungicides for the control of Rhizoctonia solani causing datnping-off of mung bean (Phaseohis aureus)

Of 41 fungicides tested in the laboratory, copper carbonate, copper sulphate, mercuric chloride, Agrosan GN, quintozene, kasugamycin, carboxin, pyracar-bolid, carbendazim, chloroneb, benomyl, Ohric, RH 893 (2-n-octyl-4-isothiazole-3-one) and Terrazole were most inhibitory to the mycelial growth of Rhizoctonia solani on Czapek's agar plates and had EC₅₀ values of less than 1 μg a.i./ml, while copper oxychloride, Udonkor, zineb, ziram, F 319 (3-hydroxy-5-methyl isoxazole) and anilazine were much less toxic, ziram being least inhibitory with an EC₅₀ of 214 μg a.i./ml. Of 17 fungicides tested in the greenhouse as seed treatments, thiabendazole, carbendazim, benomyl, thiophanate-methyl, dichlozoline and Ohric gave 80–90% control of damping-off of mung bean seedlings. A single soil drench with thiophanate-methyl and two drenches with benomyl gave about 90% disease control, More seedlings with R. solani infection survived when thiophanate-methyl was used as a post-inoculation soil drench than when benomyl or chloroneb were used.     

Degeneration of the laminated corpuscles (of Vater--Pacini) following colchicine application to a nerve]

Laminated pacinian corpuscles from the cat mesentery have been studied morphologically and morphometrically after nerve section and colchicine application to the nerve and the results obtained are represented. Similar interventions in the nerve produce changes in the receptors resembling those of wallerian type degeneration, degeneration rate after sectioning being higher than after colchicine application. At early stages after colchicine application the internal cone and its nuclei increase in size. The data obtained suggest the nuclei of the internal cone to be under neurotrophic control of the sensory neuron that might be realized via axoplasmic transport of substances.     

NUCLEAR DNA CONTENT IN POPULATIONS OF PINUS RIGIDA

Five populations of Pinus rigida growing in contrasting ecological situations ranging from North Carolina (35°53'N latitude) to Quebec (45°06'N latitude) showed no significant variation in amounts of nuclear DNA with respect to germinating seedlings. Nuclear volume of dormant nuclei also showed no significant variation between and within populations, a finding that is consistent with the concept that the basic 2C DNA value of Pinus rigida is uniform under all habitats. This finding is in contrast to numerous reports for other coniferous species.     

ULTRASTRUCTURAL ASPECTS OF TWO SPECIES OF GUTTULINOPSIS

Two acrasid cellular slime molds. Guttulinopsis vulgaris and G. nivea, are compared at the ultrastructural level. The amoebae of the two species are indistinguishable except for the presence of intranuclear fibers in G. vulgaris. Both species share some unusual features, including: plate-like cristae in the mitochondria, production of microbody-like organelles in the perinuclear space, spores with thin bilaminar walls, and stalks containing microfilaments bound in striated bundles. These and other observations are discussed with regard to the development of the sorocarps and the relationship of the genus to other members of the Acrasida.     

Comparative evaluation of the action of prostanoid inhibitors on uterine contractile function

Indomethacin and substance BW-755C in experiments on isolated myometrium striae of pregnant white rats exert an inhibiting effect on the contractile uterus function due to inhibition of cyclooxygenase or lipoxygenase ways of the arachidonic acid transformation. Prostaglandin F2 alpha is sensitive to functioning of the cyclooxygenase and lipoxygenase ways of the arachidonic acid transformation, while oxytocin--only lipoxygenase one. Conclusions rest on results from multiparametric analysis of the contractile uterus function suggested by authors and confirmed by the pattern recognition method--the Karunen-Loev orthogonal decomposition.     

Short-term delay in blood processing does not alter basal or isoproterenol-stimulated cyclic AMP accumulation in human lymphocytes

Isoproterenol-stimulated cyclic AMP (cAMP) accumulation in lymphocytes is an index of beta-adrenergic receptor functioning. It is not known if a delay between blood collection and subsequent cell preparation influences cAMP accumulation. We compared cAMP levels in lymphocytes processed from whole blood immediately after collection and following a 3.5 hour delay. There were no significant changes in either basal or stimulated levels of cAMP. This information may alleviate time constraints in certain experimental designs where immediate isolation of lymphocytes from whole blood may not be practical.     

Structure of a hemoglobin gene cluster and nucleotide sequence of three hemoglobin genes from the midge Chironomus thummi piger (Diptera, Insecta)

The aquatic larvae of the genus Chironomus (Diptera, Insecta) contain at least 12 different hemoglobin (Hb) variants in their hemolymph. In the present study we have analysed the structure and part of the nucleotide sequence of a Hb gene cluster cloned from the genomic DNA of Chironomus thummi piger. The cluster contains probably 6 different genes, separated by intergenic regions of various lengths. The nucleotide sequence of three putative Hb genes including the intergenic regions is presented. The inferred amino-acid sequences show clearly that two of these putative genes code for subvariants of the Hb variant VIIB. The third gene codes for a so far unknown Hb protein. As known already for other chironomid Hb genes, there are no intron sequences present in the coding regions.