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Sub-populations of neurons producing melanin-concentrating hormone (MCH) are characterized by distinct projection patterns, birthdates and CART/NK3 expression in rat. Evidence for such sub-populations has not been reported in other species. However, given that genetically engineered mouse lines are now commonly used as experimental models, a better characterization of the anatomy and morphofunctionnal organization of MCH system in this species is then necessary. Combining multiple immunohistochemistry experiments with in situ hybridization, tract tracing or BrdU injections, evidence supporting the hypothesis that rat and mouse MCH systems are not identical was obtained: sub-populations of MCH neurons also exist in mouse, but their relative abundance is different. Furthermore, divergences in the distribution of MCH axons were observed, in particular in the ventromedial hypothalamus. These differences suggest that rat and mouse MCH neurons are differentially involved in anatomical networks that control feeding and the sleep/wake cycle. 相似文献
995.
Marc Germain Louis Thibault Annie Jacques Jacynthe Tremblay Rémi Bourgeois 《Cell and tissue banking》2010,11(2):197-204
Heart valve allografts are typically processed at 4°C in North America, including the step of antibiotic decontamination.
In our own experience with heart valve banking, we often observe persistent positive cultures following decontamination at
wet ice temperature. We hypothesized that warmer temperatures of incubation might increase the efficacy of the decontamination
procedure. In a first series of experiments, 12 different bacterial species were grown overnight, frozen in standardized aliquots
and used directly to inoculate antibiotic cocktail aliquots at 105 colony-forming units (CFU)/ml. The antibiotic cocktail contains vancomycin (50 μg/ml), gentamicin (80 μg/ml) and cefoxitin
(240 μg/ml) in Dulbecco’s Modified Eagle’s Medium. Inoculated aliquots were incubated at 4, 22 and 37°C and CFUs were determined
at regular intervals up to 24 h post-inoculation. In a second set of experiments, 10 heart valves were spiked with 5000 CFU/ml
and incubated with antibiotics at 4 and 37°C for 24 h. The final rinse solutions of these heart valves were filtered and tested
for bacterial growth. After 24 h of incubation, CFUs of all 12 bacterial species were reduced by a factor of only one to two
logs at 4°C whereas log reductions of 3.7 and 5.0 or higher were obtained at 22 and 37°C, respectively. Most microorganisms,
including Staphylococcus epidermidis, Lactococcus lactis lactis and Propionibacterium acnes survived well the 24-h antibiotic treatment at 4°C (<1 Log reduction). All 10 heart valves that were spiked with microorganisms
had positive final rinse solutions after antibiotic soaking at 4°C, whereas 8 out of 10 cultures were negative when antibiotic
decontamination was done at 37°C. These experiments show that a wet ice temperature greatly reduces the efficacy of the allograft
decontamination process as microorganisms survived well to a 24-h 4°C antibiotic treatment. This could explain the high rate
of positive post-processing cultures obtained with our routine tissue decontamination procedure. Increasing the decontamination
temperature from 4 to 37°C may significantly reduce the incidence of post-disinfection bacterial contamination of heart valves. 相似文献
996.
B. N. Rooban V. Sasikala V. Sahasranamam Annie Abraham 《Biological trace element research》2010,138(1-3):282-292
Recently, much interest has been generated in the search for phytochemical therapeutics, as they are largely free from adverse side effects and economical. The goal of this study was to determine the efficacy of Vitex negundo in modulating the selenite-induced oxidative stress in vivo model. Sprague–Dawley rat pups of 8 days old were used for the study and divided into control (G I), selenite induced (G II), and selenite + V. negundo treated (G III). Cataract was induced by the single subcutaneous injection of sodium selenite (4 mg/kg body weight) on the tenth day and V. negundo (2.5 mg/Kg body weight) administered intraperitoneally from eighth to 15th day. Morphological examination of the rat lenses revealed no opacification in G I and mild opacification in G III whereas dense opacification in G II (stages 4–6). Levels of selenium in G II and G III showed no significant changes. The activities of superoxide dismutase, catalase, and Ca2+ATPase were significantly increased in G III compared to G II (p?<?0.05), while lower level of reactive oxygen species, Ca2+, and thiobarbituric acid reactive substances were observed in G III compared G II (p?<?0.05). These results indicate the therapeutic potential of methanolic extract of V. negundo on modulating biochemical parameters against selenite-induced cataract, which have been reported in this paper for the first time. 相似文献
997.
Giraud A Chabaud O Lejeune PJ Barbaria J Mallet B 《Biochemical and biophysical research communications》2006,346(3):746-750
Plasminogen (Pl), a circulating protease synthesized in the liver, is also present in several tissues. In the thyroid gland a Pl-like protease was found in the apical lumen where it is involved, through its proteolytic activity, in luminal degradation of thyroglobulin (Tg). Here, we showed for the first time that the Pl-like protease apically secreted by epithelial thyroid cells is sulfated, both on tyrosine residue(s) and on oligosaccharide side chains. The Pl molecule is composed of a large N-terminal moiety made of five distinct Kringle domains (K1-K5) separated by small peptidic fragments, and of a C-terminal domain with serine protease activity. Using a software tool able to predict tyrosine sulfation sites in protein sequences we localized the potential tyrosine sulfation sites of Pl. Then, we became aware that, whatever the species considered, at least three of the four potential tyrosine sulfation sites of Pl were located on Kringle sites, and more precisely, for K1, on the highly conserved binding domain of K1. We determined with the same software tool which potential sulfation sites were the most likely to be really sulfated. We hypothesize that the sulfation of these sites modulates the binding properties of Pl. 相似文献
998.
The ubiquitin binding domain ZnF UBP recognizes the C-terminal diglycine motif of unanchored ubiquitin 总被引:1,自引:0,他引:1
Ubiquitin binding proteins regulate the stability, function, and/or localization of ubiquitinated proteins. Here we report the crystal structures of the zinc-finger ubiquitin binding domain (ZnF UBP) from the deubiquitinating enzyme isopeptidase T (IsoT, or USP5) alone and in complex with ubiquitin. Unlike other ubiquitin binding domains, this domain contains a deep binding pocket where the C-terminal diglycine motif of ubiquitin is inserted, thus explaining the specificity of IsoT for an unmodified C terminus on the proximal subunit of polyubiquitin. Mutations in the domain demonstrate that it is required for optimal catalytic activation of IsoT. This domain is present in several other protein families, and the ZnF UBP domain from an E3 ligase also requires the C terminus of ubiquitin for binding. These data suggest that binding the ubiquitin C terminus may be necessary for the function of other proteins. 相似文献
999.
Insulin has been described as a potential mediator of intrinsic responses to the nutritional state in the heart due to its effects on cardiac metabolism, mainly on glucose transport. It has been demonstrated that leptin can act through some components of the insulin-signaling cascade. We investigated the association between overfeeding during lactation and alterations of insulin and leptin signaling in the heart. In summary, we analyzed a feasible cross-talk between insulin and leptin through the study of some key proteins of their cascades in the heart. In order to study the effect of overfeeding on these cascades, Wistar rats were overfed through litter size reduction to only three pups. At 10 and 21 days of life, key proteins such as insulin receptor, leptin receptor, PI3-kinase, JAK2, STAT3, and GLUT4 were measured by Western blotting. Furthermore, the pups' weight and the plasma levels of insulin, leptin and glucose were determined. Overfed animals were overweight, had high insulin and leptin plasma levels, and displayed an activation of insulin and leptin cascade, leading to an increased translocation of GLUT4. We suggest that overfeeding during lactation probably alters cardiac metabolism, through the activation of a modulated cross-talk between leptin and insulin cascades. 相似文献
1000.
It has been shown that many natural enemies of herbivorous arthropods use herbivore induced plant volatiles (HIPVs) to locate their prey. Herbivores can also exploit cues emitted by plants infested with heterospecifics or conspecifics. A study was conducted to test whether green bean HIPVs as well as odours emitted directly by spider mites influenced the orientation behaviour of the predatory mirid bug, Macrolophus caliginosus and its prey, Tetranychus urticae in a Y-tube olfactometer. Our results show that both spider mites and M. caliginosus preferred spider mite infested green bean plants to uninfested plants. For M. caliginosus this response was mediated by HIPVs whereas for T. urticae it was mediated through a composite response to both HIPVs and odours emitted directly by the conspecifics (and their associated products). The results may be of use in practical biocontrol situations, through e.g., plant breeding for improved HIPV production, conditioning of mass-reared predators to appropriate cues, and employment of “push–pull-strategies” by using HIPVs. 相似文献