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991.
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993.
Morphological changes in otolith shape with age, of young (<age 3) red snapper were examined through shape analysis and tested as an objective method for age determination. Otoliths from two collections of juvenile fish (hatchery and wild) were used in the study. First, shape analysis was applied to a series of known-age otoliths from hatchery-reared age 0, 1 and 2 fish. Multidimensional scaling and non-parametric analysis of similarities showed significant shape differences among the three age classes of fish. Discriminant function analysis and cross-validation classification showed 65.6% correct age classification based on shape variables alone, and 86.7% correct age classification with inclusion of otolith weight in the discriminant function (n?=?90). Subsequently, the method was applied to otoliths from a series of age 0, 1 and 2 wild caught red snapper. Otoliths from wild fish showed a similar age classification success rate of 68.9% based on shape variables alone and 86.7% correct age classification with the inclusion of otolith weight in the discriminant function (n?=?90). Ageing of juvenile red snapper through otolith increment counts has been difficult in past studies and this study provides an alternative, objective method of otolith shape analysis for ageing young fish of this species. 相似文献
994.
Airway epithelium controls lung inflammation and injury through the NF-kappa B pathway 总被引:4,自引:0,他引:4
Cheng DS Han W Chen SM Sherrill TP Chont M Park GY Sheller JR Polosukhin VV Christman JW Yull FE Blackwell TS 《Journal of immunology (Baltimore, Md. : 1950)》2007,178(10):6504-6513
Although airway epithelial cells provide important barrier and host defense functions, a crucial role for these cells in development of acute lung inflammation and injury has not been elucidated. We investigated whether NF-kappaB pathway signaling in airway epithelium could decisively impact inflammatory phenotypes in the lungs by using a tetracycline-inducible system to achieve selective NF-kappaB activation or inhibition in vivo. In transgenic mice that express a constitutively active form of IkappaB kinase 2 under control of the epithelial-specific CC10 promoter, treatment with doxycycline induced NF-kappaB activation with consequent production of a variety of proinflammatory cytokines, high-protein pulmonary edema, and neutrophilic lung inflammation. Continued treatment with doxycycline caused progressive lung injury and hypoxemia with a high mortality rate. In contrast, inducible expression of a dominant inhibitor of NF-kappaB in airway epithelium prevented lung inflammation and injury resulting from expression of constitutively active form of IkappaB kinase 2 or Escherichia coli LPS delivered directly to the airways or systemically via an osmotic pump implanted in the peritoneal cavity. Our findings indicate that the NF-kappaB pathway in airway epithelial cells is critical for generation of lung inflammation and injury in response to local and systemic stimuli; therefore, targeting inflammatory pathways in airway epithelium could prove to be an effective therapeutic strategy for inflammatory lung diseases. 相似文献
995.
Fuly AL Calil-Elias S Martinez AM Melo PA Guimarães JA 《The international journal of biochemistry & cell biology》2003,35(10):1470-1481
In a previous report we showed that Lachesis muta crude venom displays potent indirect hemolytic activity and myotoxicity when injected into mice. Then, a phospholipase A(2) (PLA(2)) (LM-PLA(2)-I) responsible for these activities was isolated. More recently, a catalytically active isoenzyme (LM-PLA(2)-II) with molecular mass of 18 kDa and isoeletric point at pH 5.4 was isolated from the same snake venom. LM-PLA(2)-II inhibited ADP- and collagen-induced platelet aggregation as well as induced a potent paw edema reaction in rats. Here we show that LM-PLA(2)-II induced myotoxic effects both in vitro characterized by an increase on the rate of creatine kinase (CK) release from isolated mice extensor digitorum longus (EDL) muscles and in vivo by increasing plasma CK activity of injected mice. Histological analysis showed an intense damage in muscle cells injected with LM-PLA(2)-II. It was also shown that exogenous lysophosphatidylcholine (lyso-pc) behaved as a typical myotoxin damaging muscle cells, producing myonecrosis characterized by local infiltration of inflammatory cells similarly to that observed for LM-PLA(2)-II. Hemorrhage and lethal effects were not observed neither with LM-PLA(2)-II nor lyso-pc. As previously observed for other biological activities, pretreatment of LM-PLA(2)-II with p-bromophenacyl bromide (p-BPB) or acetic anhydride abolished all the enzyme's actions. The data confirms that biological activities displayed by LM-PLA(2)-II, including the myotoxic effects reported here, are all dependent on its enzymatic activity where the product formed (lyso-pc) may play an important function on such myotoxicity. 相似文献
996.
Wanninger J Weigert J Wiest R Bauer S Karrasch T Farkas S Scherer MN Walter R Weiss TS Hellerbrand C Neumeier M Schäffler A Buechler C 《Cytokine》2011,55(3):435-440
Recently we demonstrated higher galectin-3 in portal venous serum (PVS) compared to hepatic venous serum (HVS) in a small cohort of patients with normal liver function suggesting hepatic removal of galectin-3. Here, galectin-3 was measured by ELISA in PVS, HVS and systemic venous blood (SVS) of 33 patients with alcoholic liver cirrhosis and a larger cohort of 11 patients with normal liver function. Galectin-3 was cleared by the healthy but not the cirrhotic liver, and subsequently HVS and SVS galectin-3 levels were significantly increased in the patients with liver cirrhosis compared to controls. In healthy liver galectin-3 was produced by cholangiocytes and synthesis by hepatocytes was only observed in cirrhotic liver. Hepatic venous pressure gradient did not correlate with galectin-3 levels excluding hepatic shunting as the principal cause of higher SVS galectin-3. Galectin-3 was elevated in all blood compartments of patients with CHILD-PUGH stage C compared to patients with CHILD-PUGH stage A, and was higher in patients with ascites than patients without this complication. Galectin-3 was negatively associated with antithrombin-3 whose synthesis is reduced with worse liver function. Galectin-3 positively correlated with urea and creatinine, and PVS galectin-3 showed a negative association with creatinine clearance as an accepted measure of kidney function. To summarize in the current study systemic, portal and hepatic levels of galectin-3 were found to be negatively associated with liver function in patients with alcoholic liver cirrhosis and this may in part be related to impaired hepatic removal and/or increased synthesis in cirrhotic liver. 相似文献
997.
Among gene families it is the Hox genes and among metazoan animals it is the insects (Hexapoda) that have attracted particular attention for studying the evolution of development. Surprisingly though, no Hox genes have been isolated from 26 out of 35 insect orders yet, and the existing sequences derive mainly from only two orders (61% from Hymenoptera and 22% from Diptera). We have designed insect specific primers and isolated 37 new partial homeobox sequences of Hox cluster genes (lab, pb, Hox3, ftz, Antp, Scr, abd-a, Abd-B, Dfd, and Ubx) from six insect orders, which are crucial to insect phylogenetics. These new gene sequences provide a first step towards comparative Hox gene studies in insects. Furthermore, comparative distance analyses of homeobox sequences reveal a correlation between gene divergence rate and species radiation success with insects showing the highest rate of homeobox sequence evolution. 相似文献
998.
Victoria S. Arch Sabrina S. Burmeister Albert S. Feng Jun-Xian Shen Peter M. Narins 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2011,197(6):667-675
The concave-eared torrent frog, Odorrana tormota, has evolved the extraordinary ability to communicate ultrasonically (i.e., using frequencies > 20 kHz), and electrophysiological experiments have demonstrated that neurons in the frog’s midbrain (torus semicircularis) respond to frequencies up to 34 kHz. However, at this time, it is unclear which region(s) of the torus and what other brainstem nuclei are involved in the detection of ultrasound. To gain insight into the anatomical substrate of ultrasound detection, we mapped expression of the activity-dependent gene, egr-1, in the brain in response to a full-spectrum mating call, a filtered, ultrasound-only call, and no sound. We found that the ultrasound-only call elicited egr-1 expression in the superior olivary and principal nucleus of the torus semicircularis. In sampled areas of the principal nucleus, the ultrasound-only call tended to evoke higher egr-1 expression than the full-spectrum call and, in the center of the nucleus, induced significantly higher egr-1 levels than the no-sound control. In the superior olivary nucleus, the full-spectrum and ultrasound-only calls evoked similar levels of expression that were significantly greater than the control, and egr-1 induction in the laminar nucleus showed no evidence of acoustic modulation. These data suggest that the sampled areas of the principal nucleus are among the regions sensitive to ultrasound in this species. 相似文献
999.
Leon AE Fabricio AS Benvegnu' F Michilin S Secco A Spangaro O Meo S Gion M 《The International journal of biological markers》2011,26(3):197-206
The Nanosized Cancer Polymarker Biochip Project (RBLA03S4SP) funded by an Italian MIUR-FIRB grant (Italian Ministry of University and Research - Investment Funds for Basic Research) has led to the creation of a free-access dynamic website, available at the web address https://serviziweb.ulss12.ve.it/firbabo, and of a centralized database with password-restricted access. The project network is composed of 9 research units (RUs) and has been active since 2005. The aim of the FIRB project was the design, production and validation of optoelectronic and chemoelectronic biosensors for the simultaneous detection of a novel class of cancer biomarkers associated with immunoglobulins of the M class (IgM) for early diagnosis of cancer. Biomarker immune complexes (BM-ICs) were assessed on samples of clinical cases and matched controls for breast, colorectal, liver, ovarian and prostate malignancies. This article describes in detail the architecture of the project website, the central database application, and the biobank developed for the FIRB Nanosized Cancer Polymarker Biochip Project. The article also illustrates many unique aspects that should be considered when developing a database within a multidisciplinary scenario. The main deliverables of the project were numerous, including the development of an online database which archived 1400 case report forms (700 cases and 700 matched controls) and more than 2700 experimental results relative to the BM-ICs assayed. The database also allowed for the traceability and retrieval of 21,000 aliquots archived in the centralized bank and stored as backup in the RUs, and for the development of a centralized biological bank in the coordinating unit with 6300 aliquots of serum. The constitution of the website and biobank database enabled optimal coordination of the RUs involved, highlighting the importance of sharing samples and scientific data in a multicenter setting for the achievement of the project goals. 相似文献
1000.
Julia Sanchez‐Garrido Sabrina L. Slater Abigail Clements Avinash R. Shenoy Gad Frankel 《Cellular microbiology》2020,22(4)
Enteric pathogen–host interactions occur at multiple interfaces, including the intestinal epithelium and deeper organs of the immune system. Microbial ligands and activities are detected by host sensors that elicit a range of immune responses. Membrane‐bound toll‐like receptors and cytosolic inflammasome pathways are key signal transducers that trigger the production of pro‐inflammatory molecules, such as cytokines and chemokines, and regulate cell death in response to infection. In recent years, the inflammasomes have emerged as a key frontier in the tussle between bacterial pathogens and the host. Inflammasomes are complexes that activate caspase‐1 and are regulated by related caspases, such as caspase‐11, ‐4, ‐5 and ‐8. Importantly, enteric bacterial pathogens can actively engage or evade inflammasome signalling systems. Extracellular, vacuolar and cytosolic bacteria have developed divergent strategies to subvert inflammasomes. While some pathogens take advantage of inflammasome activation (e.g. Listeria monocytogenes, Helicobacter pylori), others (e.g. E. coli, Salmonella, Shigella, Yersinia sp.) deploy a range of virulence factors, mainly type 3 secretion system effectors, that subvert or inhibit inflammasomes. In this review we focus on inflammasome pathways and their immune functions, and discuss how enteric bacterial pathogens interact with them. These studies have not only shed light on inflammasome‐mediated immunity, but also the exciting area of mammalian cytosolic immune surveillance. 相似文献