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Presents a study on vegetative propagation of southwestern plants, Ambrosia deltoidea, Buddleja marrubifolia, Vauquelinia californica and Vauquelinia corymbosa. Features of southwestern plants; Description of materials and methods for the propagation of these plants; Characteristics and features of the propagation; Evaluation of plant growth.

Recombinant adenoviruses (Ad) have been employed as vectors for a wide variety of gene therapy applications, but their use has been hindered by problems relating to efficacy and safety. The efficiency of Ad-mediated gene transfer depends on the interaction of the fibre and penton base proteins with their corresponding cell receptors. Ad infection is initiated by the formation of a high affinity complex between the fibre protein and a host cell protein that for most Ad serotypes is CAR (the coxsackie B virus and Ad receptor). A second molecule, the MHC class I, may also be involved in Ad type 2 and Ad type 5 uptake. Ad internalization results from the interaction of the penton base protein with cell surface integrins αvβ3 and αvβ5. In this study, we addressed the interaction between Ad type 5 (Ad5) and its receptors on lung derived adenocarcinoma cells in culture. Using flow cytometry, we determined the level of expression of attachment and internalization receptors that are expressed on the cell surface of A549, H322 and H441 lung-derived adenocarcinoma cells in culture. The level of αvβ1 cell surface integrin was assessed by immunoprecipitation. Measuring the level of luciferase gene expression at different viral titres quantitated Ad5 uptake by these cells. The kinetics of binding of Ad5 fibre knobs to A549, H322 and H441 cells was assessed in direct binding studies using ¹²⁵I labelling of purified recombinant Ad5 fibre-knob domains. In order to assess the functionality of integrins, adhesion assays were performed in the presence or absence of activators of integrin function. In competition experiments, prior to exposure to the virus, the cells were pre-incubated with purified recombinant Ad5 fibre-knob domains, function blocking anti-integrin antibodies, or integrin activating agents, prior to the introduction of luciferase expressing Ad5. We found that Ad5-mediated gene transfer in A549, H322 and H441 adenocarcinoma cells in culture is highly variable and that this variation correlates with specific binding of Ad5 fibre-knob domain binding to the cell surface. We also found, for the first time, that Ad5 infection is mediated by integrin αvβ1 and that functional activation of β1 integrin by means of the specific anti-β1 monoclonal antibody, TS2/16, induced increased A549 cell adhesion to fibronectin and vitronectin and also enhanced Ad5 uptake by these cells. Our studies demonstrate that the Ad5 fibre-knob domain interaction with CAR represents a major determinant of Ad5-mediated gene transfer to lung-derived adenocarcinoma cells in culture. The finding that integrin αvβ1 is involved in Ad5 infection has implications for the use of recombinant Ad5 vectors for cancer gene therapy, since αvβ1 is expressed at high levels and acts as an alternative vitronectin receptor in many epithelial and some melanoma tumours which express no αvβ3 and constant low levels of αvβ5. The fact that the β1 integrin-activating antibody TS2/16 can enhance αvβ1-mediated Ad5 infection suggests that the efficacy of Ad5-mediated gene transfer might be influenced not only by the level of cell surface expression of integrins but also by their state of activation. Copyright © 2001 John Wiley & Sons, Ltd.

Annual energy flows through populations of two sympatric species of harvester ants, Chelaner rothsteiniand Chelaner whitei, were estimated using results from laboratory measurements of respiration and field studies of foraging behaviour and population size. Annual respiration (R) of C. whiteiranged from 14·96–26·87 kJ/m2/year and of C. rothsteinifrom 9·82–17·42 kJ/m2/year. Secondary production (P) of C. whiteiranged from 5·32–11·72 kJ/m2/year and for C. rothsteinifrom 5·23–8·58 kJ/m2/year. Production efficiencies (26·33 and 33·89) and net growth efficiencies (0·36 and 0·51) of C. whiteiand C. rothsteini, respectively, were higher than that of other harvester ants (Pogonomyrmex), but were similar to values found for ant populations studied in more mesic temperate habitats. Comparisons were made of the ecological efficiencies, morphology, reproduction and foraging strategies of the two species of Chelanerin an attempt to understand the adaptive syndromes of these two species.

Discusses the plant propagation by leafy stem cuttings and the physiological processes that must be maintained in the cuttings to help root initiation. Main advantages of propagation by cuttings; Factors which affects the ability of a stem cutting to survive; Contributors to the continuing biochemical balance in the severed cutting.

Presents the Arizona yard waste compost as an alternative to media of decomposed wood chips and soil. Desirable characteristics of yard waste compost; Effect of yard waste compost on plants; Result of the study conducted to evaluate various bedding plants grown in compost produced from eucalyptus and oleander yard waste.