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81.
Wendy A Neveu Jenna L Allard Danielle M Raymond Lorraine M Bourassa Stephanie M Burns Janice Y Bunn Charles G Irvin David A Kaminsky Mercedes Rincon 《Respiratory research》2010,11(1):28
Background
Asthma is a chronic inflammatory disease of the airway that is characterized by a Th2-type of immune response with increasing evidence for involvement of Th17 cells. The role of IL-6 in promoting effector T cell subsets suggest that IL-6 may play a functional role in asthma. Classically IL-6 has been viewed as an inflammatory marker, along with TNFα and IL-1β, rather than as regulatory cytokine.Objective
To investigate the potential relationship between IL-6 and other proinflammatory cytokines, Th2/Th17 cytokines and lung function in allergic asthma, and thus evaluate the potential role of IL-6 in this disease.Methods
Cytokine levels in induced sputum and lung function were measured in 16 healthy control and 18 mild-moderate allergic asthmatic subjects.Results
The levels of the proinflammatory biomarkers TNFα and IL-1β were not different between the control and asthmatic group. In contrast, IL-6 levels were specifically elevated in asthmatic subjects compared with healthy controls (p < 0.01). Hierarchical regression analysis in the total study cohort indicates that the relationship between asthma and lung function could be mediated by IL-6. Among Th2 cytokines only IL-13 (p < 0.05) was also elevated in the asthmatic group, and positively correlated with IL-6 levels (rS = 0.53, p < 0.05).Conclusions
In mild-moderate asthma, IL-6 dissociates from other proinflammatory biomarkers, but correlates with IL-13 levels. Furthermore, IL-6 may contribute to impaired lung function in allergic asthma. 相似文献82.
Guo-Hua Ma Xue-Lin Huang Bunn Eric 《植物学报(英文版)》2006,48(11):1306-1311
We report the vegetative proliferation and new phenomenon of "secondary proliferated inflorescences" In the grass Ischaemum barbatum Retz, as determined by anatomical analysis of prepared sections of inflorescences. Leaves and shoots could be developed from the original splkelets of Inflorescences and plantlets developed when these shoots were transplanted to moist soil. "Secondary proliferated Inflorescences" is the first name here because some inflorescences that developed inadequacy are grown from the splkelet on the mother Inflorescence. Our investigation showed that this form of vegetative proliferation and secondary proliferated inflorescences development of L barbatum has arisen following late autumn fires of the previous year. It Is suggested that the sudden onset of a fire could lead to a hormone Imbalance or a chemical induction, which results in ephemeral vegetative proliferation even secondary proliferated inflorescences development in wild populations. 相似文献
83.
Bunn RC Green LD Overgaard MT Oxvig C Fowlkes JL 《Biochemical and biophysical research communications》2004,325(3):698-706
Insulin-like growth factor (IGF) signaling is critical for osteoblast development and IGF binding protein (IGFBP)-4 is one of the principle IGFBPs expressed by osteoblasts. Release of bound IGF via proteolytic degradation of IGFBP-4 is likely to be critical for osteoblast development. We have investigated whether IGF-sensitive, IGFBP-4 degradation in mouse MC3T3-E1 osteoblasts is due to the metzincin pregnancy-associated plasma protein (PAPP)-A. Degradation of IGFBP-4 by PAPP-A or MC3T3-E1 conditioned medium was enhanced by IGF-II but inhibited by mutation of basic residues at or near the PAPP-A cleavage site in IGFBP-4. Furthermore, immunodepletion of PAPP-A from MC3T3-E1 conditioned medium abolished IGFBP-4 degradation. We also found that PAPP-A messenger RNA was expressed throughout differentiation of MC3T3-E1 cells. These results demonstrate for the first time that PAPP-A is the IGFBP-4 protease in MC3T3-E1 cells, a widely used model for osteoblast development, and that PAPP-A may regulate IGF release throughout osteoblast differentiation. 相似文献
84.
Background. Colonization with Helicobacter pylori generally occurs in infancy, and the microorganism is often acquired from close family members. Rate of infant colonization may be affected by maternal immune status. Methods. To investigate the potential protective effect of anti‐H. pylori immunoglobulin G (IgG) acquired via the placenta, 65 mothers and their infants were studied from the infant's birth for 1 year. Circulating IgG antibodies were measured by enzyme‐linked immunosorbent assay (ELISA) in cord blood and every 8 weeks. Immunoblotting was performed on sera from infants with significant increases in IgG levels. Rate of infant H. pylori colonization was measured by 13C urea breath tests every 4 weeks from the age of 12 weeks. Results. Maternal and infant cord blood specific IgG levels were correlated (R2 = .747, p < .001). Infant H. pylori specific IgG fell 5‐fold compared to maternal levels over the first 6 months of life, and rose subsequently in many cases, with the development of novel immunoblot patterns. There were no significant associations between the age at first positive urea breath test and maternal or infant cord specific H. pylori IgG levels. Conclusions. Transplacentally acquired specific IgG antibody does not protect infants from colonization by H. pylori. 相似文献
85.
Thehypothesis that chemically induced stress tolerance in plants can betransferredto a larger clonal population regenerated by somatic embryogenesis wasevaluatedusing the triazole compound paclobutrazol as a chemical inducer of stresstolerance in Geranium (Pelargonium horturum Bailey). Seedswere imbibed in 3.4, 10.2 or 17.0 M (1, 3, 5 mgL–1) paclobutrazol for 24 h and germinatedfor 7 days. Hypocotyl explants were cultured in vitro toinduce somatic embryogenesis. Plants regenerated from somatic embryos wereexposed to heat stress at 56°C. Explants treated with3.4 M paclobutrazol yielded a substantially higher number ofsomatic embryos compared with untreated explants. In contrast, 17.0M paclobutrazol treatment inhibited embryogenesis producing asignificantly lower number of somatic embryos. There was no difference in theembryo number between control and 10.2 M treatment. Somaticembryos derived from 3.4 and 10.2 M paclobutrazol treatedexplants developed into plants at a faster rate than the control and 17.0M treatments. Plants derived from paclobutrazol-treatedexplants displayed a greater tolerance to heat stress compared with thecontrols. Observations in this study provide a technique for regeneratingplantsin tissue/cell culture with additional desirable traits such as stresstolerancewith minimal chemical contamination of the environment. 相似文献
86.
87.
SUMMARY 1. Genetic structure of the mayfly Bungona narilla was examined using allozymes and a section of the cytochrome oxidase I gene.
2. The study had two major aims. The first was to determine whether patterns of genetic variation in mitochondrial DNA were similar to those found previously for allozymes, i.e. that more variation was evident among pools within a single stream than among streams. The mitochondrial DNA results were similar to those reported previously for allozymes, supporting the idea that larvae within any particular pool were unrepresentative of the total population and may result from a few matings.
3. The second aim was to test the hypothesis that the variation among pools within a stream was greater after dry periods than after wet periods. This was because after wet periods, larvae would have greater opportunity for mixing because of movement among pools. This hypothesis was partly supported by the mitochondrial DNA data but not by the allozyme data, in which variation among pools was extremely low on both sampling occasions. The reasons for this difference are unclear. 相似文献
2. The study had two major aims. The first was to determine whether patterns of genetic variation in mitochondrial DNA were similar to those found previously for allozymes, i.e. that more variation was evident among pools within a single stream than among streams. The mitochondrial DNA results were similar to those reported previously for allozymes, supporting the idea that larvae within any particular pool were unrepresentative of the total population and may result from a few matings.
3. The second aim was to test the hypothesis that the variation among pools within a stream was greater after dry periods than after wet periods. This was because after wet periods, larvae would have greater opportunity for mixing because of movement among pools. This hypothesis was partly supported by the mitochondrial DNA data but not by the allozyme data, in which variation among pools was extremely low on both sampling occasions. The reasons for this difference are unclear. 相似文献
88.
Can labels suggestively influence sensory perceptions and taste? Using a “ Phantom Ingredient” taste test, we show that the presence or absence of a labeled ingredient (soy) and the presence or absence of a health claim negatively bias taste perceptions toward a food erroneously thought to contain soy. We found a label highlighting soy content made health claims believable but negatively influenced perceptions of taste for certain segments of consumers. Our results and discussion provide better direction for researchers who work with ingredient labeling as well as for those who work with soybean products. 相似文献
89.
The transport of free polymannose-type oligosaccharides from the lumen of
the endoplasmic reticulum into the cytosol has been recently demonstrated
(Moore,S.E.H., et al., 1995, EMBO J., 14, 6034-6042), but at present little
is known of the characteristics of this process. Here, it is shown that
inhibition of the transport of endogenously synthesized metabolically
radiolabeled free oligosaccharides out of the endoplasmic reticulum into
the cytosol of permeabilized HepG2 cells occurs when assays are conducted
in the presence of mannose (IC50, 4.9 mM), or its derivatives modified at
the first carbon (C1) of the sugar ring; alpha-methyl mannoside (IC50, 2.0
mM), mannoheptulose (IC50, 1.6 mM), and alpha-benzyl mannoside (IC50, 0.8
mM), whereas other monosaccharides (50 mM), differing from mannose at
position; C2 (glucose), C3 (altrose), C4 (talose), C5 (l-rhamnose), and C6
(mannoheptose), have little effect. N-Acetylglucosamine does not inhibit
oligosaccharide transport and, furthermore, although mannobioses and a
mannotriose inhibit free oligosaccharide transport, di-N-acetylchitobiose
is without effect. It is also shown that if the transport assay buffer is
either depleted of calcium ions, or supplemented with the Ca2+/Mg2+ATPase
inhibitor, thapsigargin, or with calcium ionophores, free oligosaccharide
transport out of the endoplasmic reticulum is inhibited. These results
demonstrate that the terminal nonreducing mannosyl residues of free
polymannose-type oligosaccharides and not their
N-acetylglucosamine-containing reducing termini, play an important role in
the interaction of the free oligosaccharide with the transport machinery,
and that this transport process requires the presence of calcium
sequestered in the lumen of the endoplasmic reticulum.
相似文献
90.
J. Chunwongse T. B. Bunn C. Crossman J. Jiang S. D. Tanksley 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1994,89(1):76-79
We report the tagging of a powdery mildew [Leveillula taurica (Lév.) Arnaud.] resistance gene (Lv) in tomato using RAPD and RFLP markers. DNA from a resistant (cv Laurica) and a susceptible cultivar were screened with 300 random primers that were used to amplify DNA of resistant and susceptible plants. Four primers yielded fragments that were unique to the resistant line and linked to the resistance gene in an F2 population. One of these amplified fragments, OP248, with a molecular weight of 0.7 kb, was subsequently mapped to chromosome 12, 1 cM away from CT134. Using RFLP markers located on chromosome 12, it was shown that approximately one half of chromosome 12 (about 42 cM), in the resistant variety is comprised of foreign DNA, presumably introgressed with the resistance gene from the wild species L. chilense. Further analysis of a backcross population revealed that the Lv gene lies in the 5.5-cM interval between RFLP markers, CT211 and CT219. As a prelude to map-based cloning of the Lv gene, we are currently enriching the density of markers in this region by a combination of RAPD primers and other techniques. 相似文献