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1.
Reinnervation of experimental superficial wounds in rats 总被引:1,自引:0,他引:1
Sensory reinnervation of a superficial skin wound in the rat was studied by labeling sensory axons with anterogradely transported wheat germ agglutinin-horseradish peroxidase. Reinnervation starts after 3 days from the edge of the wound as well as from beneath the wound. About 2 weeks after the production of the wound, some hyperinnervation appears to be present, but after a few additional weeks, the innervation pattern is essentially normal. The results indicate that structural recovery of sensory axons is rapid and probably complete when skin wounds heal with no or minimal scar formation. 相似文献
2.
We sought to determine whether the orexigenic hormone, ghrelin, is involved in the intrinsic regulation of food choice in rats. Ghrelin would seem suited to serve such a role given that it signals hunger information from the stomach to brain areas important for feeding control, including the hypothalamus and reward system (e.g. ventral tegmental area, VTA). Thus, in rats offered a choice of palatable foods (sucrose pellets and lard) superimposed on regular chow for 2 weeks, we explored whether acute central delivery of ghrelin (intracerebroventricular (ICV) or intra-VTA) is able to redirect their dietary choice. The major unexpected finding is that, in rats with high baseline lard intake, acute ICV ghrelin injection increased their chow intake over 3-fold, relative to vehicle-injected controls, measured at both 3 hr and 6 hr after injection. Similar effects were observed when ghrelin was delivered to the VTA, thereby identifying the VTA as a likely contributing neurobiological substrate for these effects. We also explored food choice after an overnight fast, when endogenous ghrelin levels are elevated, and found similar effects of dietary choice to those described for ghrelin. These effects of fasting on food choice were suppressed in models of suppressed ghrelin signaling (i.e. peripheral injection of a ghrelin receptor antagonist to rats and ghrelin receptor (GHSR) knock-out mice), implicating a role for endogenous ghrelin in the changes in food choice that occur after an overnight fast. Thus, in line with its role as a gut-brain hunger hormone, ghrelin appears to be able to acutely alter food choice, with notable effects to promote “healthy” chow intake, and identify the VTA as a likely contributing neurobiological substrate for these effects. 相似文献
3.
Wenbo Zhang Xuemei Xu Raymond Kao Tina Mele Peter Kvietys Claudio M. Martin Tao Rui 《PloS one》2014,9(9)
Myocardial contractile dysfunction in sepsis is associated with the increased morbidity and mortality. Although the underlying mechanisms of the cardiac depression have not been fully elucidated, an exaggerated inflammatory response is believed to be responsible. Nucleotide-binding oligomerization domain-like receptor containing pyrin domain 3 (NLRP3) inflammasome is an intracellular platform that is involved in the maturation and release of interleukin (IL)-1β. The aim of the present study is to evaluate whether sepsis activates NLRP3 inflammasome/caspase-1/IL-1β pathway in cardiac fibroblasts (CFs) and whether this cytokine can subsequently impact the function of cardiomyocytes (cardiac fibroblast-myocyte cross-talk). We show that treatment of CFs with lipopolysaccharide (LPS) induces upregulation of NLRP3, activation of caspase-1, as well as the maturation (activation) and release of IL-1β. In addition, the genetic (small interfering ribonucleic acid [siRNA]) and pharmacological (glyburide) inhibition of the NLRP3 inflammasome in CFs can block this signaling pathway. Furthermore, the inhibition of the NLRP3 inflammasome in cardiac fibroblasts ameliorated the ability of LPS-chalenged CFs to impact cardiomyocyte function as assessed by intracellular cyclic adenosine monophosphate (cAMP) responses in cardiomyocytes. Salient features of this the NLP3 inflammasome/ caspase-1 pathway were confirmed in in vivo models of endotoxemia/sepsis. We found that inhibition of the NLRP3 inflammasome attenuated myocardial dysfunction in mice with LPS and increased the survival rate in mice with feces-induced peritonitis. Our results indicate that the activation of the NLRP3 inflammasome in cardiac fibroblasts is pivotal in the induction of myocardial dysfunction in sepsis. 相似文献
4.
Nicolas Delaleu Heike Immervoll Janet Cornelius Roland Jonsson 《Arthritis research & therapy》2008,10(1):R22
Introduction
Sj?gren's syndrome (SS) is a systemic autoimmune disease that mainly targets the exocrine glands. The aim of this study was to investigate the involvement of 87 proteins measured in serum and 75 proteins analyzed in saliva in spontaneous experimental SS. In addition, we intended to compute a model of the immunological situation representing the overt disease stage of SS. 相似文献5.
H Carlsten N Nilsson R Jonsson K B?ckman R Holmdahl A Tarkowski 《Cellular immunology》1992,144(1):190-202
Estrogen is known to influence immune responses in healthy subjects in a dichotomous fashion. Thus, in number of previous studies we and others have demonstrated that B cell activities are augmented after exposure to estrogen whereas T cell reactivity is suppressed. Furthermore, it has been shown that this hormone has significant impact on the course of certain human and experimental autoimmune diseases. In this study we report that treatment with physiological doses of estradiol exerts dichotomous effects on different manifestations of the lupus disease in MRL/l mice. On one hand immune complex-mediated glomerulonephritis was significantly accelerated. This outcome was due to polyclonal B cell activation with increased production of antibodies to double-stranded DNA and formation of circulating immune complexes. In contrast, T cell-mediated lesions such as focal sialadenitis, renal vasculitis, and periarticular inflammation were all significantly ameliorated in MRL/l mice exposed to estrogen. Thus, we were able to demonstrate that, within one subject and even within one organ, administration of estrogen leads to differential outcome of SLE morbidity. We propose that the differential effect of estrogen on the manifestations of the autoimmune disease of MRL/l mice is due to its dichotomous effects on B and T cell-mediated immune responses. 相似文献
6.
Penicillium citrinum cultures have been germinated on an H2O-based medium, resuspended on a D2O-based medium and treated with [l,2-13C2] acetate. The resulting citrinin (1) has been analysed by2H and13C nuclear magnetic resonance spectroscopy and information about the metabolism of hydrogen in citrinin biosynthesis has been deduced. 相似文献
7.
Roger J. Kemble Tina L. Barsby Stephen A. Yarrow 《Molecular & general genetics : MGG》1988,213(2-3):202-205
Summary
Brassica napus cybrid plants which contain novel nucleus-mitochondria-chloroplast combinations have been constructed, via protoplast fusion. Such fusions resulted in mitochondrial DNA plasmids being lost (at a frequency of 12.5%) or, more surprisingly, being transferred from mitochondria of one protoplast population to mitochondria of the other population (at a frequency of 6.1%). Mitochondria containing their new DNA complement became the dominant organelle population in regenerated plants and were faithfully maternally inherited through successive sexnal generations. No concomitant alterations in mitochondrial chromosome organization or nuclear chromosome number occurred. Protoplast fusion can, therefore, cure plant mitochondria of extrachromosomal DNA and, more importantly, be used to transform plant mitochondria with naturally occurring mitochondrial plasmids. The potential for mitochondrial transformation with recombinant vectors is discussed. 相似文献
8.
Summary Resource utilization by cutthroat trout (CT) and Dolly Varden charr (DV) was studied 8 years after experimental transfers from sympatry had established reproducing allopatric populations in two nearby fishless lakes. Allopatric DV significantly increased their utilization of shallow-dwelling zoobenthos, and increased their vertical distribution in comparison to that in sympatry. In contrast, allopatric CT showed little change in the proportions of major prey types utilized, and, if anything, restricted their vertical distribution in comparison to that in sympatry. The results can be explained by the hypothesis that the resource use of DV is strongly influenced by interspecific competition from CT, whereas CT largely remains unaffected by this interaction. An alternative hypothesis, that lake differences can explain the differences in resource use between sympatry and allopatry, was evaluated by comparing food resource availability and other biotic and abiotic characteristics of the three study lakes. None of these could account for the shift in resource use by DV between sympatry and allopatry, but lake differences may explain why allopatric CT showed a restricted habitat use in comparison with their sympatric donor stock. The results of this whole-lake transfer experiment are consistent with earlier reported field and laboratory studies, and suggest that the aggressive dominance of CT is the most important mechanism by which DV are displaced from littoral and near-surface habitats in sympathy with CT. 相似文献
9.
Allison A. Welder Tina Machu Steven W. Leslie Richard E. Wilcox June Bradlaw Daniel Acosta 《In vitro cellular & developmental biology. Plant》1988,24(8):771-777
Summary Primary mycolardial cell cultures and freshly isolated cardiac cells in suspension resprensent two isolated, whole cell models
for investigating cellular transsarcolemmal45Ca++ exchange in response to a receptor-coupled stimulus. Studies were performed to characterize beta-adrenergic receptor binding,
beta-adrenergic receptor mediated cellular calcium (45Ca++) exchange, and viability in purified primary myocardial cell cultures and freshly isolated cardiac cells in suspension obtained
from 3-to 3-d-old Sprague-Dawley rats. In addition, beta-adrenergic receptor binding was characterized in whole-heart crude
membrane preparations. All three preparations had saturable beta-adrenergic binding sites with the antagonist [125I]iodopindolol ([125I]IPIN). The suspensions had a significantly lower B
max
(42±6 fmol/mg protein) than the membranes and cultures (77±8 and 95±10 fmol/mg protein, respectively). The K
D
of the cultures (218±2.0 pM) was significantly higher than that for the suspensions (107 ±1.3 pM) and membranes (93±1.3 pM). Viability was significantly lower in the suspensions (57%) when compared to 94% viability in myocardial cell cultures after
3 h of incubation in Kreb's Henseleit buffer. Incubation of the cultures with 5.0×10−7
M isoproterenol resulted in a significant increase in45Ca++ exchange as early as 15 s. In contrast,45Ca++ exchange into the suspensions was not increased. Although both primary cell cultures and cardiac cells in suspension possess
saturable beta-adrenergic receptors, only the monolayer cultures exhibited functional beta-adrenergic receptor-mediated45Ca++ exchange. Of the two intact cell models investigated, these data suggest that primary myocardial cell cultures are more suitable
than cell suspensions for investigating beta-adrenergic receptor binding and functions in the postnatal rat heart.
This research was supported by The University of Texas Research Institute, a grant from the Texas Advanced Research Technology
Program awarded to S. W. Leslie and R. E. Wilcox, and contract 223-86-2109 from the Food and Drug Administration. 相似文献
10.
Tina Pallesen Annette Vangsted Lars Drivsholm Henrik Clausen Jesper Zeuthen Håkan Wallin 《Glycoconjugate journal》1992,9(6):331-335
We here report an enzyme linked immunosorbent assay (ELISA) and a scintillation proximity assay (SPA) for detection of the ganglioside FucGM1 in sera from small cell lung cancer (SCLC) patients. The SPA was more sensitive and reproducible than the ELISA. In this assay, monoclonal antibodies specific for FucGM1 were bound to SPA particles and incubated with labelled FucGM1 and 100 µl test-serum overnight, and counted in a -counter. The sensitivity was 0.2 ng. Seven out of twenty sera from SCLC patients were positive, whereas none of twenty sera from healthy individuals were positive for FucGM1. The SPA was more sensitive than the previously reported HPTLC as well as a direct ELISA.Abbreviations MAb
monoclonal antibody
- SPA
scintillation proximity assay
- HPTLC
high performance thin layer chromatography
- SCLC
small cell lung cancer
- FucGM1
Fuc1-2Gal1-3GalNAc1-4(NeuAc2-3)-Gal1-4Glc1-1Cer
- ELISA
enzyme linked immunosorbent assay
- FCS
foetal calf serum
- PBS
phosphate buffered saline 相似文献