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791.
Narcotic analgetics were shown to bind cerebroside sulfate (CS) with high affinity. The binding correlated well with their pharmacological potency. In order to understand opiate receptor interaction at the molecular level, we have proposed the use of CS as a model opiate receptor. In these studies, our data indicate that the binding of opiates is determined by the heptane solubility of the drugs and their affinity to CS. The affinity of the agonist to CS is higher than that of its corresponding antagonist. The difference in affinity between an agonist and its corresponding antagonist is mainly due to the strength of electrostatic bond formed between the protonated nitrogen of the drug and the sulfate group of CS. Furthermore, we have concluded that narcotic agonist-CS complexes are more hydrophobic (intimate ion pairs formation) while the antagonist-CS complexes are more hydrophilic (hydrated ion pairs) in nature. 相似文献
792.
R. W. Roudijk K. Taha M. Bourfiss P. Loh L. van den Heuvel M. J. Boonstra F. van Lint S. M. van der Voorn A. S. J. M. te Riele L. P. Bosman I. Christiaans T. A. B. van Veen C. A. Remme M. P. van den Berg J. P. van Tintelen F. W. Asselbergs 《Netherlands heart journal》2021,29(6):301
In relatives of index patients with dilated cardiomyopathy and arrhythmogenic cardiomyopathy, early detection of disease onset is essential to prevent sudden cardiac death and facilitate early treatment of heart failure. However, the optimal screening interval and combination of diagnostic techniques are unknown. The clinical course of disease in index patients and their relatives is variable due to incomplete and age-dependent penetrance. Several biomarkers, electrocardiographic and imaging (echocardiographic deformation imaging and cardiac magnetic resonance imaging) techniques are promising non-invasive methods for detection of subclinical cardiomyopathy. However, these techniques need optimisation and integration into clinical practice. Furthermore, determining the optimal interval and intensity of cascade screening may require a personalised approach. To address this, the CVON-eDETECT (early detection of disease in cardiomyopathy mutation carriers) consortium aims to integrate electronic health record data from long-term follow-up, diagnostic data sets, tissue and plasma samples in a multidisciplinary biobank environment to provide personalised risk stratification for heart failure and sudden cardiac death. Adequate risk stratification may lead to personalised screening, treatment and optimal timing of implantable cardioverter defibrillator implantation. In this article, we describe non-invasive diagnostic techniques used for detection of subclinical disease in relatives of index patients with dilated cardiomyopathy and arrhythmogenic cardiomyopathy. 相似文献
793.
A 12 hr seed soak in a solution of 100 ppm of potassium naphthenatesresulted in 140.5% stimulation of IAA synthesis determined in58 cm tips of epicotyls of 14-day-old dark-grown Phaseolusvulgaris seedlings. (Received September 1, 1973; ) 相似文献
794.
Arnaud Delpoux Nimi Marcel Rodrigo Hess Michelini Carol D. Katayama Karmel A. Allison Christopher K. Glass Sergio M. Quiñones-Parra Cornelis Murre Liyen Loh Katherine Kedzierska Martha Lappas Stephen M. Hedrick Andrew L. Doedens 《Cell reports》2021,34(4):108674
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795.
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797.
Although the functions of hormones and neuropeptides in the thymus have been extensively studied, we still do not know whether
these intra-thymic humoral elements are released in a stimulated manner via the regulated secretory pathway or in a constitutive
manner. Carboxypeptidase E (CpE) and chromogranin A (CgA) are functional and structural hallmarks of the regulated secretory
pathway in (neuro)endocrine cells. Whereas we have previously shown a CgA-positive neuroendocrine population in the chicken
thymus, the current study assesses the expression of CpE in the thymus, both at the mRNA and the protein level. Our immunohistochemical
studies provide evidence for the co-existence of CgA and CpE in identical neuroendocrine cells in the thymus. CpE and CgA
dual-positive cells have primarily been found in the transition zone between the cortex and medulla of the thymus, an area
known to contain numerous arterioles and to be innervated by the autonomic nervous system. Our findings suggest that the diffuse
neuroendocrine system serves as a relay for nervous stimuli delivered by the sympathetic and/or parasympathetic nervous system.
Thus, these newly defined neuroendocrine cells might play an important role in the immuno-neuro-endocrine cross-talk in the
thymus, potentially enabling thymopoiesis to be fine-tuned via the regulated secretory pathway by a variety of physical and
environmental factors. 相似文献
798.
Solubilization of membrane bound opiate receptor from rat brain 总被引:1,自引:0,他引:1
Sonication of rat brain membranes for 9 minutes solubilized 35% of their stereospecific opiate binding activity; a second 9 minute sonication of the insoluble residue released an additional 21% of the original binding. The opiate binding properties of the solubilized material were highly similar to those of membrane bound receptor by a number of criteria, including affinity, effect of sodium, and the IC50 of unlabeled opiates in displacing 3H-etorphine binding. Moreover, storage of the solubilized receptor fraction for two weeks at ?20°C did not significantly change the receptor binding. Sonication thus appears to be a useful first step in purifying the opiate receptor. 相似文献
799.
The effects of the calmodulin antagonist W13 were determined on potentially lethal damage repair, sublethal damage repair, and X-ray-induced DNA damage repair following X irradiation of 67 murine mammary carcinoma cells in the proliferative and quiescent states. Studies with W13 (20 micrograms/ml) on proliferating cells showed that the cells rounded up within 2 h but stayed attached to the dishes and there was a slight transient G2 block by 6 h. Also, the proportion of S-phase cells at 12 h was reduced to 65% of control with the concurrent [3H]thymidine incorporation reduced to 62% of control. There was no detectable effect from this pharmacological dose of W13 either on PLDR in proliferating cells at 400 and 800 rad or on quiescent cells at 200 and 400 rad. Likewise, there was no measurable effect on SLDR in either proliferating or quiescent cells at equally split doses of 800 and 600 rad, respectively. In addition, for control vs W13-treated proliferating cells, no difference was detected either in the induction of DNA damage by X irradiation or in the initial rate of repair (T 1/2 approximately equal to 7 min), as measured by the alkaline filter elution assay. In contrast to uv and bleomycin-induced damage, these data suggest that calmodulin may have no major role in either the molecular or cellular recovery from X-ray-induced damage in mammalian cells. 相似文献
800.
W. K. W. Loh P. Bond K. J. Ashton D. T. Roberts I. R. Tibbetts 《Journal of fish biology》2014,85(2):307-328
The barcoding of mitochondrial cytochrome c oxidase subunit 1 (coI) gene was amplified and sequenced from 16 species of freshwater fishes found in Lake Wivenhoe (south‐eastern Queensland, Australia) to support monitoring of reservoir fish populations, ecosystem function and water health. In this study, 630–650 bp sequences of the coI barcoding gene from 100 specimens representing 15 genera, 13 families and two subclasses of fishes allowed 14 of the 16 species to be identified and differentiated. The mean ± s.e . Kimura 2 parameter divergence within and between species was 0·52 ± 0·10 and 23·8 ± 2·20% respectively, indicating that barcodes can be used to discriminate most of the fish species accurately. The two terapontids, Amniataba percoides and Leiopotherapon unicolor, however, shared coI DNA sequences and could not be differentiated using this gene. A barcoding database was established and a qPCR assay was developed using coI sequences to identify and quantify proportional abundances of fish species in ichthyoplankton samples from Lake Wivenhoe. These methods provide a viable alternative to the time‐consuming process of manually enumerating and identifying ichthyoplankton samples. 相似文献