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11.
Mary Jeanne Kreek 《Neurochemical research》1996,21(11):1469-1488
The early history of research on the possible existence of specific opioid receptors and on developing a new form of pharmacotherapy
for the treatment of heroin addiction in New York City, from 1960–1973, along with the special relationships between two leading
scientists conducting these research efforts, Dr. Eric Simon and Dr. Vincent P. Dole Jr., are presented in a historical perspective.
The linkage of these early efforts and the subsequent identification and the elucidation of the effects of exogenous opiates
acting at specific opiate receptors in human physiology, including some findings from perspective studies of heroin addicts
at time of entry to and during methadone maintenance treatment, are presented in the context of the important clues which
thereby were provided concerning the possible roles of the endogenous opioids in normal mammalian physiology. From many of
these early clinical research findings and studies in animal models, the hypothesis that the endogenous opioids system may
play an important role in stress responsivity was formulated along with the related hypothesis, first presented in the early
1970s, that an atypical responsivity to stress and stressors might be involved in the acquisition and persistence of, and
relapse to specific addictive diseases, including heroin addiction, cocaine dependency and alcoholism. More recent studies
of the possible involvement of the specific opioid receptors in these three addictive diseases—heroin addiction, cocaine addiction
and alcoholism—from our laboratory are discussed in a historical perspective of the development of these ideas from the early
research findings of not only Dr. Eric Simon, but his numerous colleagues in opioid research in the United States and throughout
the world.
Special issue dedicated to Dr. Eric J. Simon. 相似文献
12.
Shuji Nakamura David W. Stock Karen L. Wydner Jacques A. Bollekens Kenichi Takeshita Brian M. Nagai Shigeru Chiba Toshio Kitamura Thomas M. Freeland Zhiyong Zhao Jun Minowada Jeanne B. Lawrence Kenneth M. Weiss Frank H. Ruddle 《Genomics》1996,38(3):314
We have cloned a new Dlx gene (Dlx7) from human and mouse that may represent the mammalian orthologue of the newt geneNvHBox-5.The homeodomains of these genes are highly similar to all other vertebrate Dlx genes, and regions of similarity also exist between mammalian Dlx7 and a subset of vertebrate Dlx genes downstream of the homeodomain. The sequence divergence between human and mouse Dlx7 in these regions is greater than that predicted from comparisons of other vertebrate Dlx genes, however, and there is little sequence similarity upstream of the homeodomain both between these two genes and with other Dlx genes. We present evidence for alternative splicing of mouseDlx7upstream of the homeodomain that may account for some of this divergence. We have mapped humanDLX7distal to the 5′ end of the HOXB cluster at an estimated distance of between 1 and 2 Mb by FISH. Both the human and the mouse Dlx7 are shown to be closely linked to Dlx3 in a convergently transcribed orientation. These mapping results support the possibility that vertebrate distal-less genes have been duplicated in concert with the Hox clusters. 相似文献
13.
Karen L. Wydner John A. McNeil Feng Lin Howard J. Worman Jeanne B. Lawrence 《Genomics》1996,32(3):474
We have used fluorescencein situhybridization to establish precise chromosomal localizations for three human genes encoding four different nuclear envelope proteins. Lamin A/C (LMN1, HGMW-approved symbol LMNA) mapped to 1q21.2–q21.3, with a most probable gene assignment to 1q21.3; lamin B receptor (LBR) was localized to 1q42.1; and lamin B1 (LMNB1) was mapped to the interface of bands 5q23.3–q31.1. Assignments were determined by direct placement of signals relative to high-resolution DAPI or G-bands. Comparison of these results of band positions predicted from fractional length measurements to signal placement indicated that more accurate predictions are made using Francke idiograms and that measurement strategy avoids variance due to polymorphic chromosome segments. 相似文献
14.
David W. Zeh Jeanne A. Zeh 《Evolution; international journal of organic evolution》1994,48(4):1168-1182
Differences in secondary sexual characteristics of males often provide the most conspicuous means of distinguishing between closely related species. Does this therefore imply that the absence of differentiation in exaggerated male traits between allopatric populations provides evidence of a single, genetically cohesive species? We addressed this question with a comprehensive investigation of two populations (French Guiana and Panama) of the harlequin beetle-riding pseudoscorpion, Cordylochernes scorpioides. This highly sexually dimorphic pseudoscorpion is currently described as a single species, ranging throughout the Neotropics. Our morphometric analyses detected minimal differentiation between the two populations in all nine external morphological characters measured, including sexually dimorphic traits in males. Only in traits of the spermatophore was there any appreciable level of differentiation. Behavior differentiation and prezygotic reproductive isolation were also limited: 78.3% of males successfully transferred sperm to “foreign” females, and in 63.9% of these cases, females' eggs were successfully fertilized. By contrast, extensive divergence existed in two of nine electrophoretic loci, including an essentially fixed-allele difference at the Ldh locus. Most significantly, postzygotic reproductive isolation was complete, with heteropopulation zygotes invariably aborting early in development. These results strongly suggest that the two populations are, in fact, sibling species, a conclusion supported by our recently published findings on their marked divergence in minisatellite DNA. How can such interpopulation homogeneity in male sexually dimorphic traits exist in the face of strong genetic divergence? We propose that sexual selection, oscillating between favoring small and then large males, maintains such high levels of male variability within each population that it has obscured a speciation event in which genetic divergence and postzygotic incompatibility have clearly outpaced the evolution of prezygotic reproductive isolation. 相似文献
15.
Murielle Rinaldi-Carmona Francis Barth Michel Haulme David Shire Bernard Calandra Christian Congy Serge Martinez Jeanne Maruani Gervais Nliat Daniel Caput Pascual Ferrara Philippe Soubri Jean Claude Brelire Grard Le Fur 《FEBS letters》1994,350(2-3):240-244
SR141716A is the first selective and orally active antagonist of the brain cannabinoid receptor. This compound displays nanomolar affinity for the central cannabinoid receptor but is not active on the peripheral cannabinoid receptor. In vitro, SR141716A antagonises the inhibitory effects of cannabinoid receptor agonists on both mouse vas deferens contractions and adenylyl cyclase activity in rat brain membranes. After intraperitoneal or oral administration SR141716A antagonises classical pharmacological and behavioural effects of cannabinoid receptor agonists. This compound should prove to be a powerful tool for investigating the in vivo functions of the anandamide/cannabinoid system. 相似文献
16.
Mapping of resistance to the potato cyst nematode Globodera rostochiensis from the wild potato species Solanum vernei 总被引:1,自引:0,他引:1
Jeanne M. E. Jacobs Herman J. van Eck Karin Horsman Paul F. P. Arens Brigitte Verkerk-Bakker Evert Jacobsen Andy Pereira Willem J. Stiekema 《Molecular breeding : new strategies in plant improvement》1996,2(1):51-60
A population of diploid potato (Solanum tuberosum) was used for the genetic analysis and mapping of a locus for resistance to the potato cyst nematode Globodera rostochiensis, introgressed from the wild potato species Solanum vernei. Resistance tests of 108 genotypes of a F1 population revealed the presence of a single locus with a dominant allele for resistance to G. rostochiensis pathotype Ro1. This locus, designated GroV1, was located on chromosome 5 with RFLP markers. Fine-mapping was performed with RAPD and SCAR markers. The GroV1 locus was found in the same region of the potato genome as the S. tuberosum ssp. andigena H1 nematode resistance locus. Both resistance loci could not excluded to be allelic. The identification of markers flanking the GroV1 locus offers a valuable strategy for marker-assisted selection for introgression of this nematode resistance.Abbreviations BSA
bulked segregant analysis
- RAPD
random-amplified polymorphic DNA
- RFLP
restriction fragment length polymorphism
- SCAR
sequence-characterized amplified region 相似文献
17.
Summary Colonies and nests ofApoica pallens in the llanos region of Venezuela range from small foundress nests to large mature colonies. Nests are sited on small diameter, near-horizontal branches in a variety of shrub and tree species. During the day, adult wasps cluster on the face of the nest in an array that seems to be determined by orientation to gravity; defense of the colony against parasitoids and ants by the resting wasps may be more a passive than an active behavior. Wasps fan their wings to cool the colony during the day, but no foraging for water accompanies the fanning behavior. Nightly foraging activity begins with the explosive departure from the nest of hundreds of wasps, most of which rapidly return. Moderate foraging levels early at night give way to very low foraging levels in pre-dawn hours. The period of moderate foraging may be extended for longer hours during increased moonlight. Foraging wasps collect arthropod provisions for larvae. Larvae produce a trophallactic saliva; adults engage in inter-adult trophallaxis; brood are cannibalized. During cluster formation prior to swarm emigration, adult wasps do not appear to scent-mark substrates such as leaves. Instead,A. pallens exhibits a calling behavior, unique among polistine wasps studied to date, in which the gaster is held rigidly away from the thorax and metasomal sternal glands are exposed. Swarms can emigrate during the day.A. pallens may incorporate absconding and colony relocation as features of its colony cycle in the highly seasonal llanos. 相似文献
18.
The effect of cycloheximide on the chloroplastic, cytoplasmic and mitochondrial phenylalanyltransferRNA synthetases of Euglena gracilis was studied by growing both logarithmic and stationary phase cultures in the presence of the antibiotic. Enzyme activity was measured relative to untreated control cultures. At very low concentrations of cycloheximide (1 g/ml), all three log phase enzymes showed an increase in activity of 40–50%. At slightly higher concentrations (2.5 g/ml), the phenylalanyl-tRNA synthetase activities were comparable to those of the control cultures. At a cycloheximide concentration of 5g/ml the enzyme activities from stationary phase cultures showed only very slight decreases (5–20%). The cytoplasmic and mitochondrial enzymes behaved similarly in log phase cultures at this concentration. However, the chloroplastic phenylalanyl-tRNA synthetase from log phase cultures treated with 5g/ml cycloheximide showed a marked decrease in activity (70%). A further increase in antibiotic concentration to 10g/ml resulted in significant losses of activity of all three enzymes, from both growth stages. The implications of the data with regard to identification of the site(s) of chloroplast enzyme synthesis are discussed. 相似文献
19.
B. Levy A. Ghaem Jeanne M. Verpillat J. P. Martineaud 《International journal of biometeorology》1977,21(4):341-347
The hand blood flow (
) was investigated in response to a wide range of general and local cutaneous thermal stimuli (0–36°C and 4–42°C respectively), the local stimulus consisting of a thermostatically controlled water bath for the right hand (Tw), and the general stimulus, the ambient room temperature (Ta).
was measured at the right wrist by strain gauge plethysmography; it was seen to respond more significantly to variations in Tw than to those in Ta at cold to comfortable ambient temperatures (Ta<22°C). A paradoxical vasodilatation was observed at Tw=4°C (Lewis' hunting phenomenon). The graphs of
versus T at average to high local cutaneous temperatures (Tw > 33°C) are remarkably similar, except for an upward shift at successively higher values of Tw. The slope (or vasomotor reactivity) is interpreted as being controlled by variations in Ta. The curves exhibited maximum values at Ta = 31°C. Their subsequent decrease could represent a thermoregulatory adaptation to environment-organism heat transfer, the relative vasoconstriction tending to reduce the transfer. Although the qualitative
response was the same for both sexes, the absolute value of
was generally greater in male than in female subjects. 相似文献
20.
Hideki Oyama Jeanne Martin Karl Sussman Gordon C. Weir Alan Permutt 《Regulatory peptides》1981,1(6):387-396
Catfish pancreatic somatostatin, which contains eight additional amino acids on the amino terminus of a tetradecapeptide with considerable homology to tetradecapeptide somatostatin (SRIF), is a naturally occurring homology of the hypothalamic peptide. The purpose of these studies was to determibe the biological activity of this somatostatin homolog. Inhibition of 125I-labelled tyr1-SRIF binding to bovine pituitart plasma membranes by catfish pancreatic somatostatin was approximately 33% that of SRIF. Pancreatic somatostatin has full biological activity measured by inhibition of growth hormone release from isolated rat pituitary cells, but 0.01–0.1% the potency of SRIF. Pancreatic somatostatin at 100 ng/ml produced a 50–60% inhibition of insulin and glucagon secretion from perfused rat pancreas, while SRIF produced comparable inhibition at 10 ng/ml. This report demonstrates that a larger molecular form and natural homolog of SRIF, isolated from fish pancreas, has the same (but reduced) biological activities in rat assay systems as somatostatin originally isolated from sheep hypothalamus. 相似文献