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Y Gazit E Dunkelblum O Ben-Aziz M Altstein 《Archives of insect biochemistry and physiology》1992,19(4):247-260
This study describes the preparation and characterization of a highly specific antiserum to Helicoverpa zea pheromone biosynthesis activating neuropeptide (Hez-PBAN), and the use of this antiserum, in an enzyme linked immunosorbent assay (ELISA), to determine: a) the content of endogenous PBAN in head extracts of male and female Heliothis peltigera; b) the level of PBAN at different developmental stages; and c) the content of PBAN in four different moth species. Cross-reactivity studies revealed that the antiserum is directed mainly toward the N-terminal region of the neuropeptide, and that it exhibits similar binding affinities toward the oxidized and reduced forms of PBAN. Analysis of PBAN content in head extracts of male and female H. peltigera, at scotophase, revealed the presence of 4.97 and 4.58 pmol, respectively, in 3-day-old moths, and 5.33 and 4.78 pmol, respectively, in 7-day-old moths. The similarity in the content of PBAN at both ages and sexes was in accordance with the amount of pheromonotropic activity in these extracts which stimulated pheromone biosynthesis to a similar level. Analysis of PBAN-like immunoreactivity (IR) in head extracts of H. peltigera larvae and pupae demonstrated the existence of the neuropeptide in the 4th larval instar and continued to increase as a function of development. No IR could be detected in the first three larval instars. The larval and pupal extracts also exerted pheromonotropic activity which followed a similar pattern. The activity in these extracts, however, was considerably lower than that found in adult male and female heads. IR was also detected in head extracts of three other Noctuidae moths: Helicoverpa armigera, Cornutiplusia circumflexa and Spodoptera littoralis, indicating a high degree of chemical and structural similarity of PBAN in these moths. 相似文献
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Summary Induction of Epstein-Barr virus (EBV) capsid antigen synthesis in 59.6% of P3HR-1 cells was followed by a decrease to 70% in adenosine deaminase (ADA) activity. In Daudi cells synthesizing EBV early antigen, ADA activity did not decrease. 相似文献
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The wake and sleep-onset times of a patient with a sleep-wake cycle longer than 24 hr were recorded by the patient for 4 years. During this time, the patient found himself unable to maintain a 24-hr sleep-wake schedule. When treated with 1-2 mg clonazepam, taken nightly, he was able to become entrained to a 24-hr day. Despite entrainment of his sleep-wake cycle, the patient reported depression, lack of motivation and fatigue and chose not to continue taking the drug. 相似文献
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In vivo chromosomal instability in ataxia-telangiectasia homozygotes and heterozygotes 总被引:1,自引:0,他引:1
Summary The exfoliated cell micronucleus test was used to monitor in vivo chromosomal instability in a population comprised of five ataxia-telangiectasia (A-T) homozygotes and seven obligate heterozygotes (parents of A-T patients). This assay was previously validated as a procedure for quantifying non-invasively carcinogen-induced chromosomal aberrations occurring in vivo in epithelial tissues of both the oral cavity and the urinary bladder. The procedure involved taking airdried smears of three sites in the oral cavity of each examined individual. Desquamated urinary bladder cells were collected by centrifugation of freshly voided urine samples. Frequencies of exfoliated cells in these preparations were determined and compared with control values (individuals with no genetic chromosomal instability and no known carcinogene exposure) for these sites. Exforliated cell micronucleus (MEC) frequencies were elevated 5- to 14-fold in samples from the A-T homozygotes. This elevation in MEC frequency occurred for both the oral cavity and urinary bladder. Five out of the seven obligate A-T heterozygotes had an elevated MEC frequency in samples from the oral cavity. In addition, all examined urine samples from A-T heterozygotes contained an elevated percentage of micronucleated cells. These data suggest that this assay is suitable for in vivo monitoring of groups of individuals in which genetically produced chromosomal damage occurs. The possibility of A-T heterozygote detection with this simple procedure is of particular significance, since such individuals are believed to comprise up to 1% of the general population, and have been identified as being at elevated risk for cancer. 相似文献
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Isabel J. Wajda Miriam Banay-Schwartz Isaac Manigault Abel Lajtha 《Neurochemical research》1986,11(7):949-957
In vivo effects of chronic lithium administration on dopaminergic and serotonergic receptor binding were studied in the striatum and cerebral cortex of the rat. [3H]Domperidone was used as the ligand for the dopaminergic receptor, and [3H]ketanserin for the serotonergic system. Long-term ingestion of lithium (2–3 months) resulted in high levels of lithium in the cerebral cortex and significantly higher potassium levels; the sodium content remained at normal levels. The kinetic constants (K
d andB
max) of [3H]domperidone binding sites measured in the striatum did not show any deviation from control values, but the receptor concentration (B
max) of [3H]ketanserin binding sites was significantly reduced in the cerebral cortex of lithium-treated rats. The apparent dissociation constant (K
d) was not changed. The results indicate that the serotonergic component of the [3H]spiperone binding site, which we had previously found to be affected by chronic lithium treatment and which was shown by Peroutka and Snyder (1) to be the 5-HT2 receptor, is selectively affected by lithium.Special Issue dedicated to Prof. Eduardo De Robertis. 相似文献
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