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991.
Miller AL Webb MS Copik AJ Wang Y Johnson BH Kumar R Thompson EB 《Molecular endocrinology (Baltimore, Md.)》2005,19(6):1569-1583
992.
As more information becomes available regarding the role of inflammation following stroke, it is apparent that some inflammatory
mediators are detrimental and others are beneficial to the progression of ischemic injury. Cortical spreading depression (CSD)
is known to impart some degree of ischemic tolerance to the brain and to influence the expression of many genes. Many of the
genes whose expression is altered by CSD are associated with inflammation, and it appears likely that modulation of the inflammatory
response to ischemia by CSD contributes to ischemic tolerance. Understanding which inflammatory processes are influenced by
CSD may lead to the identification of novel targets in the effort to develop an acute treatment for stroke. 相似文献
993.
Migratory shorebirds need to replenish their energy reserves by foraging at stop-over sites en route. Adjusting their foraging behaviour to accommodate variation in local prey availability would therefore be advantageous. We test whether western sandpipers (Calidris mauri), a sexually dimorphic shorebird, adjust their foraging behaviour in response to local changes in prey availability, as inferred by changes in diurnal time and sediment temperature. Both males and females showed quantitative changes to foraging mode in relation to each of these variables. Probing, for example, which is used to exploit infaunal prey, was significantly more common at higher temperatures. The results presented here are consistent with the notion that western sandpipers can adjust their foraging behaviour in response to variation in prey availability. Further, we speculate that temperature-induced changes to prey location may contribute to the striking sexual segregation observed for this species during the non-breeding season. 相似文献
994.
995.
Huang WE Wang H Zheng H Huang L Singer AC Thompson I Whiteley AS 《Environmental microbiology》2005,7(9):1339-1348
Acinetobacter sp. ADP1 is a common soil-associated bacterium with high natural competency, allowing it to efficiently integrate foreign DNA fragments into its chromosome. This property was exploited to engineer salicylate-inducible luxCDABE and green fluorescent protein (GFP) variants of Acinetobacter sp. ADP1. Specifically, Acinetobacter sp. ADPWH_lux displayed the higher sensitivity when comparing the two variants (minimum detection c. 0.5-1 microM salicylate) and a faster turnover of the lux marker gene, making it suitable for whole-cell luminescence assays of salicylate concentration. In contrast, the longer maturation and turnover times of the GFP protein make the Acinetobacter sp. ADPWH_gfp variant more suited to applications involving whole-cell imaging of the presence of salicylate. The sensitivity of the luxCDABE variant was demonstrated by assaying salicylate production in naphthalene-degrading cultures. Assays using ADPWH_lux specifically mapped the kinetics of salicylate production from naphthalene and were similar to that observed by high-performance liquid chromatography (HPLC) data. However, ADPWH_lux exhibited the higher sensitivity, when compared with HPLC, for detecting salicylate production during the first 24 h of naphthalene metabolism. These data demonstrate that the engineered Acinetobacter variants have significant potential for salicylate detection strategies in laboratory and field studies, especially in scenarios where genetic stability of the construct is required for in situ monitoring. 相似文献
996.
Markus Weichselbaum Malcolm P Sparrow Elisha J Hamilton Philip J Thompson Darryl A Knight 《Respiratory research》2005,6(1):115
Background
Pulmonary neuroendocrine cells (PNEC) are specialized epithelial cells that are thought to play important roles in lung development and airway function. PNEC occur either singly or in clusters called neuroepithelial bodies. Our aim was to characterize the three dimensional morphology of PNEC, their distribution, and their relationship to the epithelial nerves in whole mounts of adult human bronchi using confocal microscopy.Methods
Bronchi were resected from non-diseased portions of a lobe of human lung obtained from 8 thoracotomy patients (Table (Table1)1) undergoing surgery for the removal of lung tumors. Whole mounts were stained with antibodies to reveal all nerves (PGP 9.5), sensory nerves (calcitonin gene related peptide, CGRP), and PNEC (PGP 9.5, CGRP and gastrin releasing peptide, GRP). The analysis and rendition of the resulting three-dimensional data sets, including side-projections, was performed using NIH-Image software. Images were colorized and super-imposed using Adobe Photoshop.Table 1
Patient Demographic DataPatient | Gender | Age | Smoking status | Disease |
1 | Male | 65 | Smoker | SSC |
2 | Male | 67 | Smoker | LSC |
3 | Female | 40 | Non-smoker | Adeno |
4 | Female | 37 | Non-smoker | LSC |
5 | Female | 61 | Ex-Smoker | Adeno |
6 | Female | 74 | Smoker | SSC |
7 | Male | 70 | Smoker | SSC |
8 | Female | 72 | Smoker | SSC |
Results
PNEC were abundant but not homogenously distributed within the epithelium, with densities ranging from 65/mm2 to denser patches of 250/mm2, depending on the individual wholemount. Rotation of 3-D images revealed a complex morphology; flask-like with the cell body near the basement membrane and a thick stem extending to the lumen. Long processes issued laterally from its base, some lumenal and others with feet-like processes. Calcitonin gene-related peptide (CGRP) was present in about 20% of PNEC, mainly in the processes. CGRP-positive nerves were sparse, with some associated with the apical part of the PNEC.Conclusion
Our 3D-data demonstrates that PNEC are numerous and exhibit a heterogeneous peptide content suggesting an active and diverse PNEC population. 相似文献997.
Although well recognized and studied in developed countries, canine parasitic zoonoses pose a lowly prioritized public health problem in developing countries such as India, where conditions are conducive for transmission. A study of the most recent parasite survey determining prevalence and epidemiology of canine parasitic zoonoses among tea-growing communities of northeast India demonstrated the endemicity of the problem. This particular study serves as a model using conventional, as well as molecular parasitological, tools to provide novel insights into the role of dogs as mechanical transmitters of human parasites such as Ascaris and Trichuris, and discusses the risks dogs pose with regards to zoonotic transmission of hookworms and Giardia. 相似文献
998.
Laboratory studies were conducted to determine effects of cytoplasmic polyhedrosis virus on diapausing Heliothis virescens. Most virus-infected individuals died in the larval stage. Infected pupae yielded as many moths as healthy. Females from surviving virus-infected larvae produced fewer eggs than those from healthy larvae, but there was no statistical difference in longevity of adults between healthy and infected groups. Infected moths yielded lower than normal quantities of extracted fatty acids. 相似文献
999.
1000.
Adult-derived stem cells and their potential for use in tissue repair and molecular medicine 总被引:3,自引:0,他引:3
Young HE Duplaa C Katz R Thompson T Hawkins KC Boev AN Henson NL Heaton M Sood R Ashley D Stout C Morgan JH Uchakin PN Rimando M Long GF Thomas C Yoon JI Park JE Hunt DJ Walsh NM Davis JC Lightner JE Hutchings AM Murphy ML Boswell E McAbee JA Gray BM Piskurich J Blake L Collins JA Moreau C Hixson D Bowyer FP Black AC 《Journal of cellular and molecular medicine》2005,9(3):753-769
This report reviews three categories of precursor cells present within adults. The first category of precursor cell, the epiblast-like stem cell, has the potential of forming cells from all three embryonic germ layer lineages, e.g., ectoderm, mesoderm, and endoderm. The second category of precursor cell, the germ layer lineage stem cell, consists of three separate cells. Each of the three cells is committed to form cells limited to a specific embryonic germ layer lineage. Thus the second category consists of germ layer lineage ectodermal stem cells, germ layer lineage mesodermal stem cells, and germ layer lineage endodermal stem cells. The third category of precursor cells, progenitor cells, contains a multitude of cells. These cells are committed to form specific cell and tissue types and are the immediate precursors to the differentiated cells and tissues of the adult. The three categories of precursor cells can be readily isolated from adult tissues. They can be distinguished from each other based on their size, growth in cell culture, expressed genes, cell surface markers, and potential for differentiation. This report also discusses new findings. These findings include the karyotypic analysis of germ layer lineage stem cells; the appearance of dopaminergic neurons after implantation of naive adult pluripotent stem cells into a 6-hydroxydopamine-lesioned Parkinson's model; and the use of adult stem cells as transport mechanisms for exogenous genetic material. We conclude by discussing the potential roles of adult-derived precursor cells as building blocks for tissue repair and as delivery vehicles for molecular medicine. 相似文献