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1.
Concentrations of glandular kallikrein in human nasal secretions increase during experimentally induced allergic rhinitis 总被引:2,自引:0,他引:2
C R Baumgarten R C Nichols R M Naclerio D Proud 《Journal of immunology (Baltimore, Md. : 1950)》1986,137(4):1323-1328
We have previously demonstrated that a mixture of bradykinin and lysylbradykinin is generated in nasal secretions during the immediate allergic response to allergen. The present studies were performed to determine whether glandular kallikrein plays a role in kinin formation during the allergic reaction. Allergic individuals (n = 7) and nonallergic controls (n = 7) were challenged intranasally with appropriate allergen, and nasal lavages obtained before and after challenge were assayed for immunoreactive glandular kallikrein as well as for histamine, kinins, and N-alpha-tosyl-L-arginine methyl esterase (TAME-esterase) activity. The increase in postchallenge immunoreactive glandular kallikrein levels above baseline was significantly greater (p less than 0.01) for the allergic group (16.3 +/- 14 ng/ml; means +/- SD) than for the nonallergic controls (1.0 +/- 1.9 ng/ml). Increased levels of immunoreactive glandular kallikrein correlated with increases in kinins, histamine, and TAME-esterase activity and with the onset of clinical symptoms. Characterization of immunoreactive glandular kallikrein purified from postchallenge lavages by immunoaffinity chromatography confirmed the identity of this material as an authentic glandular kallikrein on the basis of its inhibition by protease inhibitors and by monospecific antibody to tissue kallikrein, its chromatographic behavior on gel filtration, and its ability to generate lysylbradykinin from highly purified human low m.w. kininogen. The specific activity of this purified material, in terms of kinin generation from kininogen, was very similar to that for authentic glandular kallikrein, suggesting that most if not all of the immunoreactive material purified from nasal lavages represented active enzyme. Inhibition studies by using pooled postchallenge lavages suggest that the majority of the kinin generating activity in these samples was due to glandular kallikrein. We conclude, therefore, that glandular kallikrein is secreted during the allergic response and can contribute to the formation of the lysylbradykinin produced during the allergic reaction. 相似文献
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Anna M. Kauppi Alicia Edin Ingrid Ziegler Paula M?lling Anders Sj?stedt ?sa Gylfe Kristoffer Str?lin Anders Johansson 《PloS one》2016,11(1)
A metabolomics approach for prediction of bacteremic sepsis in patients in the emergency room (ER) was investigated. In a prospective study, whole blood samples from 65 patients with bacteremic sepsis and 49 ER controls were compared. The blood samples were analyzed using gas chromatography coupled to time-of-flight mass spectrometry. Multivariate and logistic regression modeling using metabolites identified by chromatography or using conventional laboratory parameters and clinical scores of infection were employed. A predictive model of bacteremic sepsis with 107 metabolites was developed and validated. The number of metabolites was reduced stepwise until identifying a set of 6 predictive metabolites. A 6-metabolite predictive logistic regression model showed a sensitivity of 0.91(95% CI 0.69–0.99) and a specificity 0.84 (95% CI 0.58–0.94) with an AUC of 0.93 (95% CI 0.89–1.01). Myristic acid was the single most predictive metabolite, with a sensitivity of 1.00 (95% CI 0.85–1.00) and specificity of 0.95 (95% CI 0.74–0.99), and performed better than various combinations of conventional laboratory and clinical parameters. We found that a metabolomics approach for analysis of acute blood samples was useful for identification of patients with bacteremic sepsis. Metabolomics should be further evaluated as a new tool for infection diagnostics. 相似文献
4.
Se-Chan Kim Alexander Ghanem Heidi Stapel Klaus Tiemann Pascal Knuefermann Andreas Hoeft Rainer Meyer Christian Grohé Anne A Knowlton Georg Baumgarten 《BMC physiology》2007,7(1):5
Backgound
It has been reported that Toll-like receptor 4 (TLR4) deficiency reduces infarct size after myocardial ischemia/reperfusion (MI/R). However, measurement of MI/R injury was limited and did not include cardiac function. In a chronic closed-chest model we assessed whether cardiac function is preserved in TLR4-deficient mice (C3H/HeJ) following MI/R, and whether myocardial and systemic cytokine expression differed compared to wild type (WT). 相似文献5.
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Yanyan Han Elfriede Eppinger Ingrid G. Schuster Luise U. Weigand Xiaoling Liang Elisabeth Kremmer Christian Peschel Angela M. Krackhardt 《The Journal of biological chemistry》2009,284(48):33409-33417
The formin protein formin-like 1 (FMNL1) is highly restrictedly expressed in hematopoietic lineage-derived cells and has been previously identified as a tumor-associated antigen. However, function and regulation of FMNL1 are not well defined. We have identified a novel splice variant (FMNL1γ) containing an intron retention at the C terminus affecting the diaphanous autoinhibitory domain (DAD). FMNL1γ is specifically located at the cell membrane and cortex in diverse cell lines. Similar localization of FMNL1 was observed for a mutant lacking the DAD domain (FMNL1ΔDAD), indicating that deregulation of autoinhibition is effective in FMNL1γ. Expression of both FMNL1γ and FMNL1ΔDAD induces polarized nonapoptotic blebbing that is dependent on N-terminal myristoylation of FMNL1 but independent of Src and ROCK activity. Thus, our results describe N-myristoylation as a regulative mechanism of FMNL1 responsible for membrane trafficking potentially involved in a diversity of polarized processes of hematopoietic lineage-derived cells. 相似文献
8.
Franz Peter Fischer Christina Miltz Ingrid Singer Geoffrey A. Manley 《Journal of morphology》1992,213(2):225-240
The starling cochlea was studied with TEM at four locations along the basilar papilla to investigate gradients in morphological features over the papilla's length and width. Hair cell shape changes continuously from neural to abneural and from basal to apical. Unlike the situation in mammals, there are no distinct populations of hair cells; the previously described types (tall hair cells and short hair cells) are merely extremes in a continuum. Contacts between THC are a normal feature. Except at the base of the papilla, SHC have very large cuticular plates, suggesting a micromechanical function for these cells. In contrast to the THC, the SHC normally completely lack afferent innervation; this indicates that their function is restricted to within the basilar papilla itself. © 1992 Wiley-Liss, Inc. 相似文献
9.
Abstract. 1. Pollen is considered to be an important dietary component for many species of flower-feeding herbivores. Its influence on oviposition site selection by the pollen beetle Meligethes aeneus , and on the development of its larvae was investigated.
2. The effects of pollen presence and absence on adult, egg, and larval incidence in the field, and on larval development in the laboratory were compared through the use of Synergy, a composite hybrid oilseed rape Brassica napus variety comprising male-fertile (with pollen) and male-sterile (without pollen) plants.
3. In the field, adult females were more abundant on male-fertile plants during flowering, and a greater proportion of male-fertile than male-sterile buds were accepted for oviposition. These data indicate a possible role of pollen in oviposition site selection by female pollen beetles.
4. The numbers of first instar larvae on the two plant lines did not differ; however, more second instars were found on male-fertile than on male-sterile flowers. This suggests a greater larval survival on male-fertile plants, possibly due to the more readily available food resources and better nutrition afforded by the presence of pollen.
5. Laboratory experiments confirmed that a diet which included pollen improved survival to adulthood and resulted in heavier pupae and adults; however, pollen was not obligatory for larval survival and development.
6. The pollen beetle, previously thought to be an obligate pollen feeder, is therefore more generalist in its requirements for development. These findings may relate to the nutritional and behavioural ecology of other flower-feeding herbivores. 相似文献
2. The effects of pollen presence and absence on adult, egg, and larval incidence in the field, and on larval development in the laboratory were compared through the use of Synergy, a composite hybrid oilseed rape Brassica napus variety comprising male-fertile (with pollen) and male-sterile (without pollen) plants.
3. In the field, adult females were more abundant on male-fertile plants during flowering, and a greater proportion of male-fertile than male-sterile buds were accepted for oviposition. These data indicate a possible role of pollen in oviposition site selection by female pollen beetles.
4. The numbers of first instar larvae on the two plant lines did not differ; however, more second instars were found on male-fertile than on male-sterile flowers. This suggests a greater larval survival on male-fertile plants, possibly due to the more readily available food resources and better nutrition afforded by the presence of pollen.
5. Laboratory experiments confirmed that a diet which included pollen improved survival to adulthood and resulted in heavier pupae and adults; however, pollen was not obligatory for larval survival and development.
6. The pollen beetle, previously thought to be an obligate pollen feeder, is therefore more generalist in its requirements for development. These findings may relate to the nutritional and behavioural ecology of other flower-feeding herbivores. 相似文献
10.
Frank M. Maas Luit J. de Kok Ingrid Hoffmann Pieter J. C. Kuiper 《Physiologia plantarum》1987,70(4):713-721
Exposure of spinach (Spinacia oleracea L. cv. Monosa) to 0.25 μl l?1 H2S reduced the relative growth rate by 26, 47 and 60% at 15, 18 and 25°C, respectively. Shoot to root ratio decreased in plants fumigated at 18 and 25°C. Growth of spinach was not affected by a 2-week exposure to 0.10 or 0.25 μl l?1 SO2. Both H2S and SO2 fumigation increased the content of sulfhydryl compounds and sulfate. A 2-week exposure to 0.25 μl l?1 H2S resulted in an increase in sulfhydryl and sulfate content of 250 to 450% and 63 to 248% in the shoots, respectively, depending on growth temperature. Exposure to 0.15 and 0.30 μl l?1 H2S at 20°C for 2 weeks resulted in a 46% increase in sulfate content of the shoots at 0.30 μl l?1 and no detectable increase at 0.15 μl l?1 H2S; the sulfate content of the roots increased by 195 and 145% at 0.15 and 0.30 μl l?1 H2S, respectively. Fumigation with 0.25 μl l?1 SO2 at 20°C for 2 weeks resulted in an increase in sulfhydryl content and sulfate content in the shoots of 285% and 300 to 1100%. H2S fumigation during the 12 h light period or only during the dark period resulted in identical growth reduction and accumulation of sulfhydryl compounds; they were about 50 and 67% of those observed in continuously exposed plants. H2S- and SO2-exposed plants showed an increased transpiration rate, which was mainly caused by an increased dark-period transpiration. No effect of H2S and SO2 on the water uptake of the plants and the osmotic potential of the leaves was detected. Plants fumigated with 0.25 μl l?1 H2S for 2 weeks were smaller and differed morphologically from the control plants by slightly more abaxially curved leaf margins. Cross sections of the leaves showed smaller cells at the margins and smaller and fewer air spaces. The increased transpiration in the H2S-exposed plants is discussed in relation to the observed morphological changes. 相似文献