Oviposition site and food preference of the green June beetle (Coleoptera: Scarabaeidae).

Relative preferences of green June beetle, Cotinis nitida (L.), adults and grubs for different organic fertilizers were determined in field and laboratory choice experiments. Six organic fertilizer treatments (low rate of broiler litter, high rate of broiler litter, cow manure, hay, Milorganite, or no fertilizer [the control]) were applied to sandy-loam soil and exposed to adults in 2.7 by 3.7 by 2.4-m screen cages. More eggs and larvae were found in pots treated with broiler litter (43%), cow manure (23%), and hay (30%) than in pots treated with Milorganite (4%) or no fertilizer (0%). Orientation preferences of third-instar grubs were tested in Y-tube and satellite olfactometers. Of the five treatments (broiler litter, cow manure, hay, Milorganite, and a blank control), preference was greatest for broiler litter and cow manure, but all organic fertilizer treatments were generally preferred over the blank control. These experiments suggest that use of organic fertilizers may result in higher densities of green June beetle grubs both by attracting the ovipositing females, and by acting as a food attractant for the mobile larvae.     

广东哺乳类及两栖类寄生吸虫四新种的记述（吸虫纲：蹲茎科,蛙蠕科）

作者在广东省梅县市发现四个吸虫新种:1.鼠丽色吸虫,新种Reesella ratta sp. nov., 2.后囊蛙蠕吸虫,新种Batrachotrema optstosacca sp. nov., 3.梅县后平睾吸虫,新种Opisthioparorchis meixianensis sp. nov., 4.大卵后平睾吸虫,新种Opisthioparorchis megaloonos sp. nov.,它们分别归隶于蹲茎科Cathaemasiidae及蛙蠕科Bstrachotrematidae。模式标本保存于中山医科大学寄生虫学研究所。     

Vaccinia virus recombinants expressing either the measles virus fusion or hemagglutinin glycoprotein protect dogs against canine distemper virus challenge.

cDNA clones of the genes encoding either the hemagglutinin (HA) or fusion (F) proteins of the Edmonston strain of measles virus (MV) were expressed in vaccinia virus recombinants. Immunofluorescence analysis detected both proteins on the plasma membranes of unfixed cells as well as internally in fixed cells. Immunoprecipitation of metabolically radiolabeled infected-cell extracts by using specific sera demonstrated a 76-kDa HA polypeptide and gene products of 60, 44, and 23 kDa which correspond to a MV F precursor and cleavage products F0, F1, and F2, respectively. Neither recombinant induced cell fusion of Vero cells when inoculated individually, but efficient cell fusion was readily observed upon coinfection of cells with both recombinants. Inoculation of dogs with the vaccinia virus-MV F recombinant (VV-MVF) did not give rise to detectable MV-neutralizing antibody. Inoculation of dogs with the vaccinia virus-MV HA recombinant (VV-MVHA) or coinoculation with both recombinants (VV-MVF and VV-MVHA) induced significant MV-neutralizing titers that were increased following a booster inoculation. Inoculation of dogs with the vaccinia virus recombinants or with MV failed to induce canine distemper virus (CDV)-neutralizing antibodies. Upon challenge with a lethal dose of virulent CDV, signs of infection were observed in dogs inoculated with (VV-MVF). No symptoms of disease were observed in dogs that had been vaccinated with VV-MVHA or with VV-MVHA and VV-MVF and then challenged with CDV. All dogs vaccinated with the recombinant viruses as well as those inoculated with MV or a vaccine strain of CDV survived CDV challenge.     

A hydrophobic protein sequence can override a nuclear localization signal independently of protein context.

Simian virus 40 T antigen is specifically targeted to the nucleus by the signal Pro-Lys-Lys-128-Lys-Arg-Lys-Val. We have previously described the isolation of a simian virus 40 T-antigen mutant, 676FS, which retains a wild-type nuclear localization signal but fails to accumulate properly in the nucleus and interferes with the nuclear localization of heterologous proteins. Here we report that the hydrophobic carboxy-terminal sequence novel to 676FS T antigen overrides the nuclear localization signal if fused to other proteins, thereby anchoring the proteins in the cytoplasm. We discuss possible mechanisms by which missorting of such a fusion protein could interfere with the nuclear transport of heterologous proteins.     

Localization of a base-paired interaction between small nuclear RNAs U4 and U6 in intact U4/U6 ribonucleoprotein particles by psoralen cross-linking

The small nuclear RNAs U4 and U6 display extensive sequence complementarity and co-exist in a single ribonucleoprotein particle. We have investigated intermolecular base-pairing between both RNAs by psoralen cross-linking, with emphasis on the native U4/U6 ribonucleoprotein complex. A mixture of small nuclear ribonucleoproteins U1 to U6 from HeLa cells, purified under non-denaturing conditions by immune affinity chromatography with antibodies specific for the trimethylguanosine cap of the small nuclear RNAs was treated with aminomethyltrioxsalen. A psoralen cross-linked U4/U6 RNA complex could be detected in denaturing polyacrylamide gels. Following digestion of the cross-linked U4/U6 RNA complex with ribonuclease T1, two-dimensional diagonal electrophoresis in denaturing polyacrylamide gels was used to isolate cross-linked fragments. These fragments were analysed by chemical sequencing methods and their positions identified within RNAs U4 and U6. Two overlapping fragments of U4 RNA, spanning positions 52 to 65, were cross-linked to one fragment of U6 RNA (positions 51 to 59). These fragments show complementarity over a contiguous stretch of eight nucleotides. From these results, we conclude that in the native U4/U6 ribonucleoprotein particle, both RNAs are base-paired via these complementary regions. The small nuclear RNAs U4 and U6 became cross-linked in the deproteinized U4/U6 RNA complex also, provided that small nuclear ribonucleoproteins were phenolized at 0 degree C. When the phenolization was performed at 65 degrees C, no cross-linking could be detected upon reincubation of the dissociated RNAs at lower temperature. These results indicate that proteins are not required to stabilize the mutual interactions between both RNAs, once they exist. They further suggest, however, that proteins may well be needed for exposing the complementary RNA regions for proper intermolecular base-pairing in the course of the assembly of the U4/U6 RNP complex from isolated RNAs. Our results are discussed also in terms of the different secondary structures that the small nuclear RNAs U4 and U6 may adopt in the U4/U6 ribonucleoprotein particle as opposed to the isolated RNAs.     

Diaphragm fatigue induced by inspiratory resistive loading in spontaneously breathing rabbits

Diaphragmatic contractility was assessed in spontaneously breathing ketamine-anesthetized rabbits by measuring the strength of diaphragmatic contraction in response to bilateral supramaximal phrenic nerve stimulation at frequencies between 10 and 100 Hz. During 10-180 min of inspiratory resistive loading, contractility decreased by approximately 40%, and hypoxemia and both respiratory and lactic acidosis developed. After 10 min of recovery, both the response to high-frequency stimulation (100 Hz) and the arterial PO2 and PCO2 returned to base-line levels, whereas metabolic acidosis and reduced response to low-frequency stimulation (10-20 Hz) persisted. Similar levels of hypoxemia and respiratory acidosis in the absence of inspiratory resistive loading did not alter diaphragmatic contractility. We conclude that in anesthetized rabbits excessive inspiratory resistive loading results in partially reversible diaphragm fatigue of the high- and low-frequency types, accompanied by hypoventilation and lactic acidosis.     

Isolated hepatocytes fixed on collagen, an accurate model for the the secretion of proteins in a minimal medium. Response to inflammation

The albumin, orosomuco?d and alpha 2-macroglobulin secretion by isolated hepatocytes of normal and suffering from Turpentine-induced inflammation rats, is investigated for 4 hr. The model, stable over the whole duration of incubation, is a true reflect of hepatic secretion in vivo and can be used to measure it.