bluuebunny/crossref_metadata_2025_split huggingface dataset:
Biological implications of the use of surfactants in medicines: and the biphasic effects of surfactants in biological systems
Authors: Florence Alexander T. , Gillan James M. N. 
Published: November 2006

AbstractA survey of the biological effects of surface‐active agents reveals that their affinity for membranes and in particular their ability to penetrate and increase the permeability of membranes is of prime importance. An increase in drug absorption from the gastrointestinal tract, from muscle, from the rectum and from topical preparations is frequently a result of an increase in membrane permeability; the effect of surfactants on enzyme activity can be also the result of changes in organelle permeability or to surfactant‐induced changes in protein conformation. As anionic surfactants and cationic surfactants tend to exhibit too high a degree of toxicity, non‐ionic agents are most commonly used in pharmaceuticals. Experiments to elucidate the mode of action of a range of commercially available non‐ionic surfactants on the increase in drug absorption in model systems employing goldfish (Carassius auratus) are described. Emphasis is placed on the biphasic effects of the surfactants whereby an increase in membrane permeability is observed at low concentrations (frequently below the critical micelle concentration of the surfactant) and a decrease in overall absorption is found at higher concentration. Such biphasic effects are frequently encountered in the literature on surfactant effects in biological systems.
Effect of substituted pyrazoles and related compounds on geotropism in cress seedlings
Authors: Geissler Art E. , Huppatz John L. , Katekar Gerard F. 
Published: November 2006

AbstractThe effects on root geotropism of three series of compounds related to 2‐phenyl‐8H‐pyrazolo[5,1‐a]isoindol‐8‐one (IV), its 3,3a‐dihydro derivative (V) and 5‐(2‐carboxyphenyl)‐3‐phenylpyrazole (VI) have been assessed using cress seedlings. Compounds (IV) and (VI), and their derivatives, are highly active, destroying geotropism at concentrations of 10−7‐10−9M. Substitution with various functional groups and increased molecular size resulted in only minor variation in the level of activity.
Insecticidal activity of the pyrethrins and related compounds. VII. Insecticidal dihalovinyl analogues of cis and trans chrysanthemates
Authors: Elliott Michael , Farnham Andrew W. , Janes Norman F. , Needham Paul H. , Pulman David A. 
Published: November 2006

AbstractEighteen esters of resolved cis‐ and trans‐3‐(2,2‐difluoro, ‐dichloro or ‐dibromovinyl)‐2,2‐dimethylcyclopropanecarboxylic acids with 5‐benzyl‐3‐furylmethyl, 3‐phenoxybenzyl and α‐cyano‐3‐phenoxybenzyl alcohols were prepared and evaluated for insecticidal activity against Musca domestica L. and Phaedon cochleariae Fab. Chlorine and bromine substituted esters are more active, in general, than those with fluorine, and in the most active esters, the cis isomer is more effective than the trans.
Resistance to some organophosphorus insecticides in field populations of Myzus persicae from sugar beet in 1974
Authors: Needham Paul H. , Devonshire Alan L. 
Published: November 2006

AbstractFollowing the failure of insecticides to control Myzus persicae on sugar beet, populations from the field were examined for susceptibility to dimethoate. Topical application of discriminating doses of dimethoate showed a 30‐fold variation in susceptibility between different populations. After this preliminary screening, clones were established from some populations and their resistance determined by both topical application and a systemic bioassay. This confirmed resistance to dimethoate and demonstrated resistance to demeton‐S‐methyl. There was no resistance to some other compounds tested. In all populations tested, resistance was associated with increased carboxylesterase activity.
Inactivation of triforine by u.v. and sunlight on glass and on leaves of bean plants
Authors: Buchenauer Heinrich 
Published: November 2006

AbstractTriforine is sensitive to u.v. and sunlight. The photochemical inactivation rate was higher in aqueous solution than in the solid state. In aqueous solution 50% of triforine was inactivated after 3 h irradiation with u.v. light and after 30 h exposure to sunlight. Eighty hours were necessary to decompose 25% of triforine in the solid state with sunlight on glass. The half life of triforine residues on the leaves of bean plants was about 60 h when exposed to solar irradiation. The inactivation of triforine by u.v. light and sunlight was accelerated in the presence of the sensitising chemicals riboflavin and xanthene; however, rhodamine B (C.I. 45170) showed only a small photosensitising activity.
Interstitial air movement in model grain silos
Authors: Berck Ben 
Published: November 2006

AbstractSulphur hexafluoride, SF6, was used as a gaseous tracer to determine the rate of unassisted air movement in the microclimate of grain stored in steel bins. The airspeeds were influenced by the nature of the stored products, the size and geometrical shape of the kernels and the storage temperature. Air movement rates varied from 3 to 108 in/h depending on the temperature gradients. This is the first quantitative evidence of the ultraslow speed of air movement in stored grain.
Inhibitors of choline acetyltransferase as potential insecticides
Authors: Baillie Alister C. , Corbett John R. , Dowsett John R. , Sattelle David B. , Callec Jean‐Jacques 
Published: November 2006

AbstractCholine acetyltransferase (E.C.2.3.1.6) catalyses the synthesis of acetylcholine and is therefore a target for a new insecticide. We have prepared a variety of compounds, mainly choline analogues, as inhibitors of this enzyme. One of these, 2‐isothiocyanatoethyltrimethylammonium iodide, has a Ki of 0.06 μM (Km for choline is 150 μM) and is apparently the most powerful inhibitor known for this enzyme. Although some of our compounds are insecticidal we believe, on the basis of electrophysiological studies, that they act, not on choline acetyltransferase, but on the acetylcholine receptor of the insect.
Penetration of bean leaves by asulam as influenced by adjuvants and humidity
Authors: Babiker Abdel G. T. , Duncan Henry J. 
Published: November 2006

AbstractPenetration of bean (Vicia faba var. Maris Bead) foliage by asulam was found to be affected differently by different surfactants. Some anionic and non‐ionic surfactants brought about a significant increase compared with the aqueous control, others were similar to the aqueous control and one caused a significant reduction. High humidity increased asulam uptake and the effect was still further enhanced in the presence of Tween 20. High humidity was also found to influence asulam penetration in the presence of glycerol. With urea, uptake was greater under high humidity conditions and in the presence of Tween 20. A similar enhancement of penetration was found with potassium ethyl xanthate at lower concentrations (0–0.20%) in the presence of Tween 20. On the other hand, reduced uptake resulted at higher concentrations (0.40–1.00%). Tributyl phosphate brought about an increase in penetration at concentrations greater than 0.75%. However, both potassium ethyl xanthate and tributyl phosphate were shown to damage the leaf surface.
Some chemical and physical properties of epronaz, a new herbicide
Authors: Brookes Robert F. , Copping Leonard G. 
Published: November 2006

AbstractA brief account is given of the work leading up to the synthesis of epronaz (BTS 30 843), 1‐(N‐ethyl‐N‐propylcarbamoyl)‐3‐propylsulphonyl‐1,2,4‐triazole, a new pre‐ and early post‐emergence herbicide for annual grasses. The synthesis is described, together with the occurrence and isolation of all three possible positional isomers in the final (carbamoylation) stage. The evidence for the structure assigned to epronaz is presented together with that for the other two isomers, and their interconversion is described. Some chemical properties of epronaz are described, with particular reference to its hydrolysis and its ability to function as a carbamoylating agent, in relation to persistence in the environment and to mode of action respectively. Some physical properties are also reported, including vapour pressure, solubility, and spectra. The mass spectral fragmentation pattern is also discussed.
Spray deposit cover and fungicide distribution obtained by low and ultralow volume spraying of intensive apple trees
Authors: Cooke Barry K. , Herrington Pamela J. , Jones Kenneth G. , Morgan Norman G. 
Published: November 2006

AbstractSpray deposit assessments were made on the leaf surfaces in the top, middle and base zones of intensively grown dessert apple trees sprayed by a conventional high volume automatic mast method applying 2250 litres/ha, an experimental low and ulfralow volume tractor mist blower, applying 225 litres/ha at normal dilution, 45 litres/ha at five times normal concentration or 22.5 litres/ha at ten times normal concentration, and a modified proprietary hand‐directed fan‐disc sprayer applying 225 or 22.5 litres/ha. Fluorescent tracer assessments showed that the high volume method gave heavy cover on upper and lower surfaces of the leaves in all zones, the tractor mist method gave lighter but uniform cover and the fan‐disc sprayer gave sparse cover on the upper surfaces at the top and on the lower surfaces at the base zone. The hand‐directed low and ultralow volume methods, applying one‐tenth of the amounts of copper fungicide/ha, gave deposit levels 5–30 % of those of the high volume method and the tractor mist applications gave 0.8–5.2%. The corresponding captan deposits from 5–6 applications were 12–50% and 10–20%: residual deposits from the ultralow volume applications of the concentrated captan were greater than the low volume applications of the same quantities in dilute form. In general, the order of pest and disease control obtained by the three methods was high volume automatic, fan‐disc and experimental mist, and this was related to the order of deposit levels: the order of control by the three volume rates was 2250, 225 and 22.5 litres/ha, and this could be related to the degree of spray cover.
Simulation of herbicide persistence in soil .III. Propyzamide in different soil types
Authors: Walker Allan 
Published: November 2006

AbstractThe effects of soil temperature and soil moisture content on the rate of degradation of propyzamide in five soils were examined under controlled laboratory conditions. Half‐lives in soils incubated at field capacity varied from 23 to 42 days at 25°C and from 63 to 112 days at 15°C. The variation in half‐life at 25°C and 50% of field capacity was from 56 to 94 days. When the laboratory data were used in conjunction with the relevant meteorological records and soil properties in a computer simulation program, predicted degradation curves for propyzamide in four of the soils in micro‐plots were in close agreement with those observed. Use of the program to predict residues of propyzamide in the fifth soil at crop maturity in a series of field experiments concerned with continuity of lettuce production gave values fairly close to those observed when appropriate corrections were made for initial recoveries.
The control in vitro of Ceratocystis ulmi by amine cations
Authors: Clifford Derek R. , Cooke Louise R. , Davies Susan M. 
Published: November 2006

AbstractOf 60 amine cations tested in vitro for activity against Ceratocystis ulmi, that of methyl benzimidazol‐2‐ylcarbamate (carbendazim) showed the highest activity, this being constant with three different associated anions. Some guanidines, 2‐nitro‐morpholine and 2‐(thiazol‐4‐yl)benzimidazole (thiabendazole) showed considerable activity but a large group of alkylamines, 1‐methylalkylamines and poly‐amines were relatively inactive.
Uptake, distribution and metabolic fate of 3H‐triforine in plants .I. Short‐term experiments
Authors: Fuchs Adriaan , De Vries Frits W. , Aalbers André M. J. 
Published: November 2006

AbstractMost of the label, present in the roots of bean, tomato and barley seedlings after short‐term root‐treatment with 3H‐triforine, appeared only weakly adsorbed on to the root tissue and was desorbed after transplanting in fungicide‐free soil. Label taken up accumulated almost exclusively in the leaves present at the time of treatment; all leaves expanding after termination of the treatment remained virtually devoid of radioactivity. In “adult” plants label was usually present in a concentration gradient from roots to youngest leaves; in tomato plants, however, distribution of label was rather irregular. Time‐course studies with bean and barley plants revealed that the aerial parts were gradually supplied with label, from old to youngest leaves, the maximum relative accumulation of radioactivity slowly moving acropetally. Under the experimental conditions chosen, triforine was converted nearly quantitatively to one metabolite, which almost certainly is different from any known non‐enzymic breakdown product of the fungicide.
Metabolism of the insecticide SD 8280, 2‐chloro‐1‐(2,4‐dichlorophenyl)vinyl dimethyl phosphate, following its application to rice
Authors: Roberts Terry R. , Stoydin George 
Published: November 2006

AbstractThe metabolism of the insecticide SD 8280 [2‐chloro‐1‐(2,4‐dichlorophenyl)vinyl dimethyl phosphate] in rice plants has been examined. When rice seedlings were treated with [14C]‐SD 8280 the major metabolite was 1‐(2,4‐dichlorophenyl)ethanol which was present mainly conjugated with plant carbohydrates. This compound was also the major metabolite present in grain and straw from rice treated with [14C]‐SD 8280 and grown to maturity under paddy conditions both in the glasshouse and in an outdoor enclosure. Other metabolites detected in the mature plants included 2‐chloro‐1‐(2,4‐dichlorophenyl)vinyl methyl hydrogen phosphate and 2,4‐dichloro‐benzoic acid, both of which occurred in free and conjugated forms. Paddy water was sampled at intervals after the application of [14C]‐SD 8280 and the total residue in the water fell from initial levels of 0.28–1.1 μg/ml (expressed as SD 8280 equivalent) immediately after treatment to <0.01 μg/ml after 2–3 weeks. The total residues in the soil from these experiments were low and did not exceed 0.20 mg/kg (SD 8280 equivalents) through the 0–15 cm profile.
Insecticidal activity of the pyrethrins and related compounds VIII. Relation of polarity with activity in pyrethroids
Authors: Briggs Geoffrey G. , Elliott Michael , Farnham Andrew W. , Janes Norman F. , Needham Paul H. , Pulman David A. , Young Stephen R. 
Published: November 2006

AbstractComparing insecticidal activities of a wide range of pyrethroids with polarities measured by reversed phase, thin‐layer chromatography suggests that there are optimum polarities for potency in both Musca domestica and Phaedon cochleariae, and that these optima have closely similar values. The significance of these conclusions is discussed.
1‐alkylcyclopropanecarboxylates: An extension of pyrethroid structure—activity relationships
Authors: Bolton Roge R. G. 
Published: November 2006

Abstract1‐Alkylcyclopropanecarboxylic acids are synthesised by thermolysis of 1‐pyrazolines prepared by 1,3‐dipolarcycloadditions of diazoalkanes. The insecticidal and acaricidal activities of 14 pyrethroid esters of these acids are considered in relation to the influence of steric and metabolic factors on activity. 1‐Alkyl compounds are less active than esters with no alkyl group at position 1, contrary to expectations, and also less active than the corresponding 2‐alkyl esters.
Nerve membrane as a target of pyrethroids
Authors: Narahashi Toshio 
Published: November 2006

AbstractNerve membrane is one of the most important target sites of pyrethroids. Changes in excitability of nerve fibres caused by allethrin can be satisfactorily accounted for in terms of ionic permeabilities of the membrane. Temperature has a profound effect on the allethrin‐induced permeability changes.
Development of resistance to pyrethroids in insects resistant to other insecticides
Authors: Farnham Andrew W. , Sawicki Roman M. 
Published: November 2006

AbstractResistance to pyrethroids in insects is rare, but its recent rapid development in the field suggests that this resistance may be facilitated by previous exposure to or by resistance to insecticides of unrelated groups. To test this houseflies of strain 49r2b, originally resistant to dimethoate in the field, were selected eight times during ten generations with either pyrethrum extract or bioresmethrin with or without piperonyl butoxide or with dimethoate. Selecting with any of the pyrethroids led to resistance to these insecticides and in particular to pyrethrum/piperonyl butoxide. Selecting with pyrethrum/piperonyl butoxide resulted in strongest resistance to the pyrethroids tested, whereas selecting with bioresmethrin/piperonyl butoxide resulted in least resistance. These results show that dimethoate‐resistant flies selected with pyrethroids can readily develop resistance to these insecticides, but development of resistance can be minimised by using bioresmethrin/piperonyl butoxide. The implications of these findings on the sequential use of insecticides are discussed.
Distribution and loss of phorate residues in the foliage of broad bean plants following root uptake of 14C‐labelled phorate
Authors: Galley D. John , Foerster Luis A. 
Published: November 2006

Abstract14C‐Methylene labelled phorate was added to nutrient solutions supplying the roots of young broad bean plants and after 24 h absorption, fresh nutrient was substituted. The radiolabel accumulated at the leaf margins was initially associated with solvent‐soluble toxic metabolites. Radiolabel extracted from foliage which developed after the treatment was mainly in water‐soluble form. The maximum concentration of toxic material occurred in the marginal areas of the leaves after 5 or 6 days and in the central portions after 2 days. The concentrations declined to half of their peak values in 4–6 days from leaf‐margin tissue and in 2 days from the central tissues. Water‐soluble label did not accumulate to any significant extent. Most was found in the marginal areas but concentrations built up slowly reaching a maximum after about 2 weeks, declining slowly thereafter.
Measurement of herbicide spray deposits on foliage by fluorescence I. Paraquat deposits on Vicia faba
Authors: Sharp Rex B. 
Published: November 2006

AbstractAn investigation revealed a paraquat‐compatible fluorochrome that fluoresces at 600 nm where the herbicide fluorescence is negligible. Acceptable amounts of this fluorochrome are recoverable from dry spray deposits of paraquat + fluorochrome mixture sprayed on various broad‐leaf weeds and bean leaves but care must be taken if a wetting agent is used for extraction purposes because the fluorescent intensity of the fluorochrome is affected by wetting agents. A procedure is given for extracting and measuring the fluorochrome from spray deposits on foliage.
Uptake of some volatile alkyl methylphosphonofluoridates from the vapour phase by wheat plants
Authors: Howells David J. , Hambrook Joy L. , Allenby Eleanor A. 
Published: November 2006

AbstractThe uptake of cyclohexyl, isopropyl and 1,2,2‐trimethylpropyl methylphosphonofluoridates from the vapour phase by growing wheat plants was studied. The compounds were absorbed through the leaves of the plants and were degraded in a manner similar to that following their uptake through the roots from hydroponic culture solution. The levels of the methylphosphonic acid derivatives in the plant extracts were influenced by the vapour concentration of the methylphosphonofluoridate, the period of exposure to the vapour and the state of illumination of the plants, but were not markedly influenced by the chemical nature of the compounds. Likely mechanisms for the uptake are discussed and it is concluded that the main route of absorption involves the stomata. The studies suggest that growing plants can absorb and possibly have a “sink effect” for atmospheric organophosphorus contamination.
Diazinon poisoning in large white butterfly larvae and the influence of sesamex and piperonyl butoxide
Authors: Wahla Mahmud A. , Gibbs R. Geoffrey , Ford John B. 
Published: November 2006

AbstractThe toxicity of diazinon and diazoxon to fourth instar Pieris brassicae larvae was determined, with or without modifying chemicals. Piperonyl butoxide and sesamex antagonised diazinon but synergised diazoxon. The penetration, excretion and internal concentration of diazinon were measured following topical application. Penetration of diazinon followed first order kinetics and was considerably slower after pretreatment with sesamex and piperonyl butoxide. Pretreatment with piperonyl butoxide increased the internal concentration of diazinon, but the onset of symptoms of poisoning was delayed, presumably because of inhibition of diazinon activation.
Accumulation patterns and fungicidal effect of carbendazim and thiabendazole in peanut plants after soil injection
Authors: Aharonson Nadav , Solel Zvi 
Published: November 2006

AbstractCarbendazim and thiabendazole applied to the rhizosphere of peanut plants by injection into the soil at doses of 0.1, 0.5 and 2.5 g per 1 m row, accumulated in the leaves during the first week after treatment, the concentrations being related to the doses applied. Two weeks after treatment the concentrations of both fungicides dropped sharply. During the rest of the season, whilst the concentration of carbendazim in the high‐dose treatment was 0.1 mg/kg fresh weight, the concentration of thiabendazole increased from 0.1 to 2.0 mg/kg and remained at this level until harvest. At the end of the growing season treated plants were less infected with Cercospora leaf spot (Cercospora per sonata) than the untreated control, thiabendazole affording better protection than carbendazim. Plants treated with the highest dose of thiabendazole were the only ones that did not wilt, even though infected. Laboratory studies of the adsorption of these fungicides on soil revealed that carbendazim is less adsorbed and also less persistent than thiabendazole.
Dosage values obtained following pre‐plant fumigation for perennials II. Using special methods of applying methyl bromide and 1,3‐dichloropropene nematicides
Authors: McKenry M. V. , Thomason I. J. 
Published: November 2006

AbstractThe movement of 1,3‐dichloropropene and methyl bromide was monitored in various field situations involving fumigant application coupled with contemporary soil profile modification techniques. The soil moisture, temperature, texture and profile differences are reported in each case. A combination of soil modification and soil fumigation may provide for better plant response than either treatment alone. Spot and strip treatments may provide an efficient method of applying certain pre‐plant fumigants to protect young perennials.
The mode of action of insecticides: Accelerated water loss and reduced respiration in insecticide‐treated Musca domestica L.
Authors: Gerolt Philip 
Published: November 2006

AbstractContact with organophosphorus, carbamate, organochlorine and pyrethroid insecticides caused accelerated water loss from all major parts of the integument of the housefly. The response appeared to be specific in that only insecticides, and not their truly non‐toxic analogues, had this effect, specificity being also reflected in resistance and in synergistic and antagonistic responses. As an insecticide dispersed laterally in the integument the effect spread to more distant parts, including the intestinal and tracheal systems, its arrival in the tracheal system coinciding with a reduction in the rate of respiration. It is suggested that this reaction of the integument to contact with insecticides is the primary cause of eventual death. Interference with the water balance in the tracheal system affects the normal exchange of the respiratory gases and thus proper respiratory control, to which the insect reacts with symptoms of excitation and paralyses. Degeneration of vital tissues following the loss of water is probably ultimately responsible for the death of the insect.