bluuebunny/crossref_metadata_2025_split huggingface dataset:
Vitamin C enhancement of brood rearing by caged honeybees fed a chemically defined diet
Authors: Herbert E. W. , Vanderslice J. T. , Higgs D. J. 
Published: February 2005

AbstractPollen collected by bees was sampled during a 3‐h period once a week from April to October 1983 and analyzed for vitamin C (L‐ascorbic acid and dehydroascorbic acid). The levels were highly variable and ranged from a low of 136 μg/g pollen (April) to a high of 1943 μg/g pollen (May). Overall, caged honeybees fed diets containing 1,000 and 2,000 μg/g L‐ascorbic acid reared significantly more bees to the sealed stage than bees fed diets with 500 μg/g ascorbic acid or control bees. The levels of vitamin C in prepupae reared by bees ranged from 64.5 to 103.5 μg/g body mass. Vitamin C is either synthesized from simple precursors or from symbiotic microorganisms in the gut since honeybees fed the ascorbic acid‐free control had equivalent levels of ascorbic acid to those fed the enriched diets. The total diet consumption by bees during the 10‐week study showed that the four diets were equally attractive.
Agonistic action of synthetic analogues of quisqualic acid at the insect neuromuscular junction
Authors: Miyamoto T. , Oda M. , Yamamoto D. , Kaneko Junko , Usui Toako , Fukami J. 
Published: February 2005

AbstractOne hundred twenty analogues of quisqualic acid were synthesized and assayed on the neuromuscular junction of larva of the mealworm, Tenebrio molitor. Two new agonists for amino acid receptors, L‐glutamic acid N‐thiocarboxyanhydride (L‐GANTA) and DL‐hydantoinpropionic acid (DL‐HPA), were discovered in this study. L‐GANTA and DL‐HPA produced muscle membrane depolarization, accompanied by a reduction of the muscle input resistance. The amplitude of excitatory postsynaptic potentials was decreased in the presence of L‐GANTA and DL‐HPA. The apparent dissociation constants obtained from dose‐depolarization plots were 7 x 10−4 M for L‐GANTA and 9 x 10−4 M for DL‐HPA. Some structural constraints imposed on agonists at amino acid receptors on insect muscle were discussed.
Rapid in vitro activation of corpora allata by extracted locust brain allatotropic factor
Authors: Gadot Michal , Applebaum Shalom W. 
Published: February 2005

AbstractBrains of young (newly emerged) adult female locusts (Locusta migratoria migratorioides) and of mature (> 9 days old) locusts contain an extractable allatotropic factor, soluble in 100% methanol and in distilled water. This factor stimulates juvenile hormone III (JH III) synthesis and release from corpora allata (CA) that have been excised from donor locusts and then incubated with (radiolabeled methyl)‐methionine in vitro in its presence. In addition to JH III, which is the major product synthesized by the CA, other hexanesoluble, radiolabeled compounds–‐more polar than JH III–‐are also released when CA are incubated in vitro. The activation of CA by the allatotropic factor is rapid and quickly declines when the factor is removed from the medium. Corpora allata excised from young females are marginally active and can be activated by brain allatotropic factor to less of an extent than CA of mature locusts. The content of allatotropic factor in brains of mature locusts is higher than that ascertained in brains of young females. Allatotropic factor is also present in the corpora cardiaca.
Juvenile hormone acid methyltransferase activity in imaginal discs of Manduca sexta prepupae
Authors: Sparagana Steven P. , Bhaskaran Govindan , Barrera Punnee 
Published: February 2005

AbstractThe occurrence of a peak of juvenile hormone (JH) during the prepupal period has been noted in several lepidopterans. In Manduca sexta and Hyalophora cecropia this peak is known to prevent the precocious onset of adult differentiation in imaginal tissues. However, it has previously been observed in our laboratory that corpora allata (CA) of this age are incapable of making JH owing to a lack of the terminal synthetic enzyme, juvenile hormone acid methyltransferase (JHAMT). Since the CA are required for normal pupation, it is likely that JH acid is the product released by the prepupal CA. Therefore, we analyzed whether JH acid treatment would prevent precocious adultoid differentiation in allatectomized M. sexta larvae. JH acid injections were found to be as effective as JH in normalizing pupation, and acted in a time‐ and dose‐dependent manner. This finding led to a question of whether injected or endogenous JH acid could be methylated to JH. Homogenates of several tissues from prepupae were assayed for the presence of JHAMT. Of the tissues assayed, only imaginal discs possessed significant levels of the enzyme. These results support our previously proposed mechanism for production of the prepupal JH peak in M. sexta.
New ecdysteroid conjugate: Isolation and identification of 26‐hydroxyecdysone 26‐phosphate from eggs of the tobacco hornworm, Manduca sexta (L.)
Authors: Thompson Malcolm J. , Weirich Gunter F. , Rees Huw H. , Svoboda James A. , Feldlaufer Mark F. , Wilzer Kenneth R. 
Published: February 2005

AbstractThe major ecdysteroid conjugate present in eggs (48–64 h old) of the tobacco hornworm has been purified by XAD‐2 chromatography, C18 SEP‐PAK separations, and ion suppression reversed‐phase high‐performance liquid chromatography. Enzymatic hydrolysis of the conjugate with acid phosphatase from human seminal fluid gave 26‐hydroxyecdysone. The conjugate was identified as 26‐hydroxyecdysone 26‐phosphate by nuclear magnetic resonance and fast atom bombardment mass spectrometry. This compound is also the major conjugate of newly laid eggs (0–1 h old) of the tobacco hornworm. The role for ecdysteroid conjugates is discussed.
Comparative studies on ecdysone metabolism between mature larvae and pharate pupae in the fleshfly, Sarcophaga peregrina
Authors: Moribayashi Atsuko , Kurahashi Hiromu , Ohtaki Tetsuya 
Published: February 2005

AbstractMetabolites of radioactive ecdysone or 20‐hydroxyecdysone in larvae and pharate pupae of Sarcophaga peregrina were separated and identified by using thin‐layer chromatography, high‐performance liquid chromatography, and chemical methods. At the larval stage ecdysone was metabolized to biologically less active ecdysteroids predominantly through 20‐hydroxyecydsone, at the pharate pupal stage, to other ecdysteroids which were tentatively identified as 26‐hydroxyecdysone, 3‐epi‐26‐hydroxyecdysone, and 3‐epi‐20,26‐dihydroxyecdysone. Ecdysteroid acids were found in the polar metabolites during pharate pupal‐pupal transformation, but scarcely detected in the larval metabolites. These acids were presumed to be ecdysonoic acid, 20‐hydroxyecdysonoic acid, and their epimers. The conjugates of ecdysteroid that released the free ecdysteroids by enzymatic hydrolysis were produced more in larvae than in pupae, whereas the very polar ecdysteroids that were not affected by the enzyme were found more in pupae. Therefore, there are different metabolic pathways of ecdysone between these two successive developmental stages, and the alteration of the metabolic pathway may serve as one of the important factors in a regulatory mechanism of molting hormone activity which is responsible for normal development of this insect.
Ecdysone 20‐monooxygenase in mitochondria and microsomes of Manduca sexta (L.) Midgut: Is the dual localization real?
Authors: Weirich Gunter F. , Svoboda James A. , Thompson Malcolm J. 
Published: February 2005

AbstractThe dual localization of ecdysone 20‐monooxygenase in mitochondria and microsomes of Manduca sexta larval midgut was investigated. Cosubstrate requirements and response to osmolarity of the microsomal ecdysone 20‐monooxygenase system were found to be different from those previously reported for the mitochondrial enzyme system. The microsomal monooxygenase utilized NADPH and, less efficiently, NADH as cosubstrates. NADPH and NADH effects were neither additive nor synergistic. NADPH yielded identical activities in isotonic and hypotonic incubations. Mitochondria and microsomes showed no synergistic interaction for ecdysone 20‐hydroxylation. After washing of the mitochondria, a large proportion of their ecdysone 20‐monooxygenase activity was lost. The extent of the loss was inversely correlated to the concentration of mitochondria in the incubation mixture. The addition of bovine serum albumin to the incubations (2 mg/ml) largely restored the original activities. The microsomal contamination in mitochondrial pellets after each of three successive washings was determined by measuring the activity of a microsomal marker enzyme, NADPH‐cytochrome c reductase. At each step of the purification, the ecdysone 20‐monooxgenase activity of the mitochondrial preparations far exceeded the activity attributable to the microsomal contamination. These results confirm the existence of two independent ecdysone 20‐monooxygenase systems in the midgut of M. sexta larvae.
Sterols of phytophagous and omnivorous species of Hymenoptera
Authors: Svoboda James A. , Lusby William R. 
Published: February 2005

AbstractThe sterols of six species of Hymenoptera including two phytophagous species (Apis mellifera and Megachile rotundata) and four omnivorous species (Dolichovespula maculata, Vespula maculifrons, Formica exsectoides, and Solenopsis invicta) were isolated and identified. The two phytophagous species of bees have in common relatively high levels of 24‐methylenecholesterol and very low levels of cholesterol (<1% of total sterols). The isofucosterol content (40.7%) of M. rotundata was nearly three times that of A. mellifera, but overall utilization of dietary sterols in the two species is similar in that neither is able to convert C28 and C29 phytosterols to cholesterol. All four omnivorous species are predatory to some extent, and the fact that their usual dietary sterols include high levels of chlosterol is reflected in the sterols isolated from these species, which contain 45–81% cholesterol. All six hymenopteran species appear to utilize dietary sterols for structural needs with little or no metabolic modification of the steroid structure.
Superoxide dismutase in the housefly, Musca domestica (L.)
Authors: Bird Thomas G. , Salin Marvin L. , Boyle John A. , Heitz James R. 
Published: February 2005

AbstractFour superoxide dismutase (SOD) (E.C. 1.15.1.1) isozymes were present in whole tissue homogenates of Musca domestica when examined by polyacrylamide gel electrophoresis. One of the isozymes contained manganese, and the other three contained copper and zinc. All were observed in each of the body tagma (head, abdomen, and thorax) and at each developmental stage (egg to adult).The copper‐ and zinc‐containing isozymes purified from newly emerged, adult M. domestica had a relative molecular weight of 34,800 as determined by gel filtration chromatography but consisted of two equal‐size subunits of 16,000 as measured by sodium dodecylsulfate polyacrylamide gel electrophoresis. An isoelectric point between 4.8 and 5.1 was measured. Approximately 2 mol each of copper and zinc were present per dimer. The three copper, zinc isozymes were identified as charge variants. The amino acid composition of the enzyme was similar to that of copper, zinc‐containing superoxide dismutases from other sources.Purified housefly copper, zinc superoxide dismutase was neither deactivated nor able to protect lactic dehydrogenase against deactivation in the presence of light and rose bengal, a known generator of singlet oxygen. The role of SOD in the phototoxic reaction involving rose bengal is discussed.
Inhibition of hydrocarbon biosynthesis in the housefly by 2‐Octadecynoate
Authors: De Renobales Mertxe , Wakayama Edgar J. , Halarnkar Premjit P. , Reitz Ronald C. , Pomonis J. George , Blomquist Gary J. 
Published: February 2005

AbstractThe elongation of [9,10‐3H]oleoyl‐CoA with malonyl‐CoA to form 20, 22, and 24 carbon monounsaturated fatty acids was demonstrated in housefly microsomes by radio‐GLC. These elongation reactions, which have been postulated to be involved in hydrocarbon biosynthesis, have not been previously demonstrated in insects. 2‐Octadecynoate (18:1 Δ2=) inhibited the in vivo incorporation of [1‐14C]acetate into both fatty acids and hydrocarbons in a dose‐dependent manner. At doses of 10 μg per female housefly of the alkynoic acid, the incorporation of [1‐14C]acetate into hydrocarbon was inhibited 93%, the incorporation of [9,10‐3H]oleate into hydrocarbon was inhibited 64%, and the incorporation of [1‐14C]acetate into total internal lipid was inhibited 65%. Partially purified FAS was inhibited 50% and 95% at 15 μM and 40 μM, respectively, of the alkynoic acid. These results show that 2‐octadecynoate inhibits hydrocarbon biosynthesis in the housefly by inhibiting FAS, and the in vivo data suggest that the elongation of 18:1 to longer chain fatty acids is also inhibited.
Binding of insecticides to lipophorin and arylphorin, two hemolymph proteins of Heliothis zea
Authors: Haunerland Norbert H. , Bowers William S. 
Published: February 2005

AbstractThe binding of different insecticides to hemolymph proteins of the corn earworm, Heliothis zea, was studied by an analytical isoelectric focusing technique. Two proteins capable of binding hydrophobic substrates were discovered and identified as lipophorin and arylphorin. Lipophorin, the major lipoprotein of Heliothis zea, demonstrated rather unspecific binding of xenobiotics of different hydrophobicities. Arylphorin, a putative storage protein, revealed strong affinity for compounds of medium polarity, binding only weakly to insecticides of higher or lower polarity.
Proteolytic enzymes and blood digestion in the mosquito, Culex nigripalpus
Authors: Borovsky Dov 
Published: February 2005

AbstractThe synthesis of proteolytic enzymes in the fat body and midgut of female Culex nigripalpus was followed. The effects of brain factor(s) and RNA levels in the fat body were correlated with the synthesis of proteolytic enzymes. Trypsinlike activity in the midgut of C. nigripalpus accounted for 80% of total proteolytic activity, whereas chymotrypsinlike activity accounted for 5–7% of total proteolytic activity. Synthesis of porteases in the midgut and fat body reached a peak at 35 h and 22 h after the blood meal, respectively. In the fat body, proteolytic enzyme activity fell to a low level 30 h after the blood meal, but activity in the midgut reached a low level 58 h after the blood meal. The presence of low protease activity in the fat body at the time of peak vitellogenin synthesis indicated that processing of vitellogenin was not done in this tissue.Fat bodies incubated in vitro in the presence of [14C]valine synthesized a [14C]labeled trypsinlike molecule identified as such with antitrypsin antibodies and specific substrate p‐toluene‐sulphonyl‐L‐arginine methylester (TAME) and on disc gel electrophoresis in the presence of dodecyl sulfate. The sizes of the proteins found inside and outside the peritrophic membrane were determined by gel‐chromatography and disc gel electrophoresis in the presence of dodecyl sulfate. The molecular weight (± SEM) of the largest polypeptide that migrated through the peritrophic membrane into the ectoperitrophic space was found to be 23,000 ± 2,000 daltons. Based on these results, a model is proposed to account for blood digestion in the mosquito midgut, along with the role of the peritrophic membrane.
Ecdysteroids in testis sheaths of Heliothis virescens larvae: An immunocytological study
Authors: Loeb M. J. 
Published: February 2005

AbstractTestes of last‐instar larvae of the lepidopteran, Heliothis virescens, were examined by an immunocytological technique to locate tissues associated with ecdysteroids. Antiecdysteroid antibody, prepared in rabbits, was incubated with sections of testis. Sections were then exposed to antirabbit antibody coupled to horseradish peroxidase. Oxidized 3,3‐diaminobenzidine allowed visualization. Ecdysteroid was detected in tissues of the inner layer of the testis sheath and its extensions that form the follicle walls.
Properties of larval and imaginal membrane‐bound digestive enzymes from Trichosia pubescens
Authors: Espinoza‐Fuentes Fernando P. , Terra Walter R. 
Published: February 2005

AbstractTrichosia pubescens larval midgut ceca cells display in their plasma membranes α‐glucosidases (Mr 95,000; pHo 5.5; Km 5.7 mM; Ki for TRIS 8.9 mM), trehalases (Mr 69,000; pHo 5.3; Km 0.92 mM; Ki for TRIS 57 mM), and aminopeptidases (Mr 95,000; pHo 8.7; Km 0.19 mM) which are solubilized by Triton X‐100. The enzymes were purified by electrophoresis and used to raise antibodies in a rabbit. T. pubescens imaginal midgut cells display in their plasma membranes an α‐glucosidase (Mr 156,000; pHo 5.8; Km 2.3 mM; Ki for TRIS 0.2 mM), a trehalase (Mr 93,000; pHo 5.5; Km 0.72 mM; Ki for TRIS 45.5 mM), and an aminopeptidase (Mr 210,000; pHo 9.0; Km 0.47 mM). Antiserum produced against the larval enzymes shows no precipitation arc when tested by double immunodiffusion or by immunoelectrophoresis with Triton X‐100‐solubilized membrane proteins from imaginal midguts. Otherwise, a similar test showed that larval midgut cecal enzymes and larval ventriculus enzymes display complete immunological identity. The data suggest that, despite the fact the larval and imaginal aminopeptidase, α‐glucosidase, and trehalase probably have similar functions, the genes coding for them in larvae and imagoes must differ.
Studies on vitellogenin from the tobacco hornworm, Manduca sexta
Authors: Osir Ellie O. , Wells Michael A. , Law John H. 
Published: February 2005

AbstractIn the tobacco hornworm moth, Manduca sexta, vitellogenin (Vg) is a very high‐density (1.29 g/ml) phosphoglycolipoprotein containing 13% lipids, 3% carbohydrates, and 0.6% protein‐bound phosphorus. Vitellogenin (Mr∼500,000) has two apoproteins designated apoVg‐l (Mr 177,000 ± 3,600) and apoVg‐ll (Mr45,000 ± 5,000). ApoVg‐l and apoVg‐II can be dissociated with 6 M guanidine HCI and separated from each other by gel permeation chromatography. Immunoblotting experiments using antibodies against the apoproteins showed that apoVg‐l and apoVg‐II antigens were immunologically distinct polypeptides. Antibodies against Vg reacted only with apoVg‐l. Antibodies against Vg and apoVg‐l reacted with Vg in double immunodiffusion experiments, whereas antibodies against apoVg‐II did not. These results suggest that in the native Vg molecule, apoVg‐II is positioned inside the molecule away from the aqueous environment. Only apoVg‐I contained covalently bound carbohydrate as shown by fluorescein isothiocyanateconjugated concanavalin A, periodate‐Schiff reagent, and in vivo labeling with 3H‐Man. In vivo labeling with 32P‐inorganic phosphate and chemical determination showed that apoproteins of both Vg and vitellin contain covalently bound phosphate groups.
Clones of Aedes albopictus cells resistant to methylmercaptopurine riboside
Authors: Malinoski Frank J. , Stollar Victor 
Published: February 2005

AbstractFour clones of A. albopictus cells resistant to 6‐methylmercaptopurine riboside (MMPR) (MMPR‐10, ‐11, ‐12, and ‐21) were isolated after mutagenesis of the parental LT C‐7 cells. As assayed by plating efficiencies these clones were from ten‐ to 20‐fold more resistant to MMPR than the LT C‐7 cells. Resistance was also demonstrated by the fact that concentrations of MMPR, which reduced the levels of ATP and GTP in LT C‐7 cells, had no such effect in the MMPR‐resistant cells. When de novo purine biosynthesis was measured by the incorporation of [14C]formate into ATP and GTP, MMPR had little effect on the MMPR‐10 cells (15% inhibition) but did depress synthesis considerably in the MMPR‐11 cells (80% inhibition) although not as severely as in the LT C‐7 cells (95% inhibition). Three of the resistant clones which were tested also showed considerable resistance to guanosine. Although the mechanism of resistance to MMPR in these cells is not clear it likely involves some alteration in one of the early enzymes involved in purine biosynthesis. Resistant as well as sensitive cells showed a new high‐performance liquid chromatography peak after treatment with MMPR suggesting that there was no defect in the uptake of MMPR. The conversion of labeled adenosine to AMP, ADP, and ATP in the resistant cells indicated that these cells were not deficient in adenosine kinase, another possible mechanism of resistance to MMPR. All clones showed a reduction in GTP following treatment with ribavirin; however, they varied considerably with respect to the amount of ribavirin triphosphate which they formed. In the case of the MMPR‐11 cells the amount of ribavirin triphosphate formed was markedly sensitive to cultural conditions. The fact that the various MMPR‐resistant cells responded differently to ribavirin, and that quantitative differences were also seen in their responses to MMPR (as measured by [14C]formate incorporation) and to guanosine, suggests that there are significant phenotypic differences among these resistant clones.
Cuticular hydrocarbons from six species of tephritid fruit flies
Authors: Carlson D. A. , Yocom S. R. 
Published: February 2005

AbstractCuticular alkanes obtained from larvae and adults of six species of tephritid fruit flies, Anastrepha ludens, A. suspensa, Ceratitis capitata, C. rosa, Dacus cucurbitae, and D. dorsalis were analyzed by gas chromatography. The same four major alkanes were shown to be present by capillary GC‐mass spectra in all Anastrepha and Ceratitis larvae. Profiles were obtained from individual larvae and adult specimens that showed statistical differences between species, whereas profiles of conspecific life forms including pupae of A. suspensa from different locations showed some similarities. Sexual dimorphism was not observed in alkanes extracted from adults. A novel series of alkadienes was found in all Anastrepha and Ceratitis but not in Dacus.
Biochemical effects of sublethal doses of cypermethrin on the sixth‐instar larvae of Tribolium castaneum (Herbst.)
Authors: Saleem Mushtaq A. , Shakoori A. R. 
Published: February 2005

AbstractEffects of sublethal doses ie, 2, 4, 10, and 20 ppm of cypermethrin, were studied on the sixth‐instar larvae of Tribolium castaneum (Herbst.). Of all the biochemical parameters tested, the free amino acids and cholesterol content and the activity of amylase were found to be the most sensitive components. Glutamate pyruvate transaminase activity was elevated at all doses except 2 ppm. The activities of alkaline phosphatase and glutamate oxaloacetate transaminase and glucose content were raised significantly at doses of 10 and 20 ppm. Acid phosphatase activity and the soluble protein content increased at a dose of 20 ppm. Total lipid and triglycerides, however, decreased significantly at this sublethal dose. Other biochemical parameters, such as cholinesterase and lactate dehydrogenase activities and the total protein, urea, glycogen, DNA, and RNA contents, were not significantly affected by exposure to different doses of cypermethrin.
Ecdysone 20‐hydroxylation in imaginal wing discs of Pieris brassicae (lepidoptera): Correlations with ecdysone and 20‐hydroxyecdysone titers in pupae
Authors: Blais Catherine , Lafont René 
Published: February 2005

AbstractEcdysone 20‐hydroxylase activity has been detected in pupal wing discs of Pieris brassicae. This activity is due to an enzyme system located in microsomal fractions. Its apparent Km is 58 nM for ecdysone. The enzyme is inhibited by the reaction product 20‐hydroxyecdysone with an apparent Ki of 2.6 μM. Its activity varied during pupal‐adult development with a maximum on day 4, when ecdysone levels are the highest in the animal. Although low, the peak activity is sufficient to assure 25% of the conversion of endogenous ecdysone into 20‐hydroxyecdysone in pupae. Ecdysone and 20‐hydroxyecdysone levels were measured in hemolymph and whole animals; ecdysone appears to be mainly located in hemolymph, whereas 20‐hydroxyecdysone seems to be equally distributed between hemolymph and tissues. All these findings are discussed in relation to the roles of ecdysone and 20‐hydroxyecdysone during pupal‐adult development.