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41.
A TLR4 polymorphism is associated with asthma and reduced lipopolysaccharide-induced interleukin-12(p70) responses in Swedish children 总被引:11,自引:0,他引:11
Fagerås Böttcher M Hmani-Aifa M Lindström A Jenmalm MC Mai XM Nilsson L Zdolsek HA Björkstén B Söderkvist P Vaarala O 《The Journal of allergy and clinical immunology》2004,114(3):561-567
BACKGROUND: Bacterial signals play an important role in the maturation of the immune system. Polymorphisms in genes coding for receptors to bacterial components can alter the immune responsiveness of the host to microbial agents and may indicate the development of aberrant immune responses that are associated with immune-mediated diseases such as atopic diseases. OBJECTIVE: The study's objective was to investigate the relationship between TLR4 and CD14 gene polymorphisms, the LPS responsiveness of PBMCs, and the presence of asthma and allergic rhinoconjunctivitis in children. METHODS: The TLR4 (Asp299Gly) and CD14/-159 polymorphisms were determined in 115 Swedish children aged 8 and 14 years. LPS-induced IL-12(p70), IL-10, and IFN-gamma responses of PBMCs from 69 of the children were analyzed by means of ELISA. The levels of soluble CD14 in serum samples were analyzed by means of ELISA, and the total IgE levels were analyzed by means of UniCAP Total IgE (Pharmacia Diagnostics, Uppsala, Sweden). RESULTS: Decreased LPS-induced IL-12(p70) and IL-10 responses were associated with the TLR4 (Asp299Gly) polymorphism and independently with asthma, especially atopic asthma. The TLR4 (Asp299Gly) polymorphism was associated with a 4-fold higher prevalence of asthma in school-aged children (adjusted odds ratio 4.5, 95% CI 1.1-17.4) but not to allergic rhinoconjunctivitis. CONCLUSION: A TLR4 polymorphism modifies innate immune responses in children and may be an important determinant for the development of asthma. This may influence the outcome of intervention studies that use microbial stimuli as immune modulators. 相似文献
42.
A path analysis of published reports on family resemblance reveals an important role for genetic factors in all lipids and lipoproteins, with no evidence of a discrepancy between twins and other relatives (which might be due to dominance or epistasis) nor between studies which used environmental indices and those which did not. Family environment within population is less important and is significantly greater for twins than for other relatives. 相似文献
43.
Karl-Henrik Gustavson Ylva Flodérus Sten Jagell Lennart Wetterberg Svante B. Ross 《Clinical genetics》1982,22(1):22-24
Catechol-O-methyltransferase (COMT) activity in erythrocytes was measured in six children with Down's syndrome and in their parents to determine if COMT activity is related to a gene on chromosome 21. A gene dosage effect was a possible explanation of the COMT value in three of the children but not in the other three. 相似文献
44.
Human monocytes were prepared from peripheral blood by buoyant density centrifugation and subsequent absorption-elution on a column of gelatin beads. The eluted fraction containing 60-80% monocytes was used as feeder layer in cloning of the human lymphoma line RH-L4, the human myeloma line SKO-007, and a human hybridoma cell derived from the latter line. Cloning efficiencies were high in both liquid and semisolid media with all 3 cell lines tested. Feeder monocytes could also be successfully used after having been stored in liquid nitrogen. 相似文献
45.
46.
STUDY OBJECTIVES: Based on studies of the impact of esophageal pressure on cardiovascular variables during sleep, this signal can be used to refine the severity level in the clinical diagnosis of obstructive sleep apnea syndrome. We hypothesized that relative changes in diaphragmatic electromyogram (EMG) can reflect short-term changes in esophageal pressure durng obstructive apneas and hypopneas. DESIGN: Diaphragmatic EMG was sampled at 0.25 kHz; diaphragmatic EMG waveform was band-pass filtered and digitally converted; the electrocardiogram artifact was eliminated; using a gating procedure, the waveform was fast-Fourier transformed and digitally rectified; and a moving average of 200 milliseconds was calculated. For each inspiratory effort during apnea or hypopnea, we calculated maximum diaphragmatic EMG and esophageal pressure. Data were normalized calculating the percentage difference between the first obstructed and each subsequent inspiratory effort during the respiratory event. SETTING: Sleep disorders laboratory. PATIENTS: 9 patients with moderate obstructive sleep apnea syndrome presenting with apneas and hypopneas during sleep. INTERVENTION: None. MEASUREMENTS AND RESULTS: 861 respiratory events were scored, and the evolution between esophageal pressure and diaphragmatic EMG were compared. Normalized data showed a good correlation between the 2 measures during apneas and hypopneas. There was a significant difference between the percentage increase in esophageal pressure and diaphragmatic EMG for apneas and hypopneas (esophageal pressure, apnea: 118.1% +/- 118.5%, hypopnea: 76.1% +/- 74.3%, P = .000; diaphragmatic EMG, 123.5% +/- 131.7%, hypopnea: 73.3% +/- 74.2%, P = .000). No significant differences for apnea or hypopnea were noted between the 2 measures under investigation. CONCLUSION: Diaphragmatic EMG may be clinically useful to describe relative changes in respiratory effort under conditions of apnea and hypopnea during sleep and to reliably dissociate central from obstructive events where esophageal pressure monitoring is not readily available. 相似文献
47.
Epidermal growth factor and insulin short-term increase hPepT1-mediated glycylsarcosine uptake in Caco-2 cells 总被引:5,自引:0,他引:5
Nielsen CU Amstrup J Nielsen R Steffansen B Frokjaer S Brodin B 《Acta physiologica Scandinavica》2003,178(2):139-148
AIMS: Little is known about the physiological regulation of the human intestinal di/tri-peptide transporter, hPepT1. In the present study we evaluated the effects of epidermal growth factor (EGF) and insulin on hPepT1-mediated dipeptide uptake in the intestinal cell line Caco-2. METHODS: Caco-2 cells were grown on filters for 23-27 days. Apical dipeptide uptake was measured using [14C]glycylsarcosine([14C]Gly-Sar). HPepT1 mRNA levels were investigated using RT-PCR, cytosolic pH was determined using the pH-sensitive fluorescent probe BCECF. RESULTS: Basolateral application of EGF increased [14C]Gly-Sar uptake with an ED50 value of 0.77 +/- 0.25 ng mL-1 (n = 3-6) and a maximal stimulation of 33 +/- 2% (n = 3-6). Insulin stimulated [14C]Gly-Sar uptake with an ED50 value of 3.5 +/- 2.0 ng mL-1 (n = 3-6) and a maximal stimulation of approximately 18% (n = 3-6). Gly-Sar uptake followed simple Michaelis-Menten kinetics. Km in control cells was 0.98 +/- 0.11 mM (n = 8) and Vmax was 1.86 +/- 0.07 nmol cm-2 min-1 (n = 8). In monolayers treated with 200 ng mL-1 of EGF, Km was 1.11 +/- 0.05 mM (n = 5) and Vmax was 2.79 +/- 0.05 nmol cm-2 min-1 (n = 5). In monolayers treated with 50 ng mL-1 insulin, Km was 1.03 +/- 0.08 mM and Vmax was 2.19 +/- 0.06 nmol cm-2 min-1 (n = 5). Kinetic data thus indicates an increase in the number of active transporters, following stimulation. The incrased Gly-Sar uptake was not accompanied by changes in hPepT1 mRNA, nor by measurable changes in cytosolic pH. CONCLUSIONS: Short-term stimulation with EGF and insulin caused an increase in hPepT1-mediated uptake of Gly-Sar in Caco-2 cell monolayers, which could not be accounted for by changes in hPepT1 mRNA or proton-motive driving force. 相似文献
48.
Leif Bergdahl Lennart Boquist 《Virchows Archiv : an international journal of pathology》1973,358(3):225-239
Summary A search was made for patients with associated secondary hyperparathyroidism and hypercalcemia: 22 such cases were found in the literature and 22 were recorded among 92 patients operated upon because of parathyroid disease. In the remaining 70 patients the effect of the operation on the serum calcium level was investigated: persisting hypercalcemia after the operation was found in 28 per cent of the cases.The patients reporded in the literature possessed severe renal and skeletary changes and light microscopic evidence of parathyroid adenoma (2 cases), hyperplasia (15 cases), or hyperplasia and adenoma (5 cases).The other 22 patients had histories of long-standing renal disease, most often chronic pyelonephritis, of varying severity. Skeletary roentgenograms were often normal. Morphologic examination of the parathyroids showed adenoma (6 cases) or hyperplasia (16 cases). Postoperatively, normal serum calcium level was found in 9 cases and persisting hypercalcemia in 13 (=59 per cent) cases. One patient possessed also a malignant -cell insuloma and Zollinger-Ellison's syndrome.It is suggested that secondary hyperparathyroidism may develop in patients with only slight or moderate impairment of renal function, that hypercalcemia occurs more often than previously believed in secondary hyperparathyroidism, and that some cases of secondary hyperparathyroidism previously, erroneously have been classified as primary hyperparathyroidism.Supported by grants from the Swedish Medical Research Council (Project No. B72-17X-3499-01), the Swedish Cancer Society (Project No. 552-B71-01P), and the Medical Faculty, University of Umeå. 相似文献
49.
C. U. Nielsen J. Amstrup R. Nielsen B. Steffansen S. Frokjaer B. Brodin 《Acta physiologica (Oxford, England)》2003,178(2):139-148
Aims: Little is known about the physiological regulation of the human intestinal di/tri‐peptide transporter, hPepT1. In the present study we evaluated the effects of epidermal growth factor (EGF) and insulin on hPepT1‐mediated dipeptide uptake in the intestinal cell line Caco‐2. Methods: Caco‐2 cells were grown on filters for 23–27 days. Apical dipeptide uptake was measured using [14C]glycylsarcosine([14C]Gly‐Sar). HPepT1 mRNA levels were investigated using RT‐PCR, cytosolic pH was determined using the pH‐sensitive fluorescent probe BCECF. Results: Basolateral application of EGF increased [14C]Gly‐Sar uptake with an ED50 value of 0.77 ± 0.25 ng mL?1 (n = 3?6) and a maximal stimulation of 33 ± 2% (n = 3?6). Insulin stimulated [14C]Gly‐Sar uptake with an ED50 value of 3.5 ± 2.0 ng mL?1 (n = 3?6) and a maximal stimulation of approximately 18% (n = 3?6). Gly‐Sar uptake followed simple Michaelis‐Menten kinetics. Km in control cells was 0.98 ± 0.11 mM (n = 8) and Vmax was 1.86 ± 0.07 nmol cm?2 min?1 (n = 8). In monolayers treated with 200 ng mL?1 of EGF, Km was 1.11 ± 0.05 mM (n = 5) and Vmax was 2.79 ± 0.05 nmol cm?2 min?1 (n = 5). In monolayers treated with 50 ng mL?1 insulin, Km was 1.03 ± 0.08 mM and Vmax was 2.19 ± 0.06 nmol cm?2 min?1 (n = 5). Kinetic data thus indicates an increase in the number of active transporters, following stimulation. The incrased Gly‐Sar uptake was not accompanied by changes in hPepT1 mRNA, nor by measurable changes in cytosolic pH. Conclusions: Short‐term stimulation with EGF and insulin caused an increase in hPepT1‐mediated uptake of Gly‐Sar in Caco‐2 cell monolayers, which could not be accounted for by changes in hPepT1 mRNA or proton‐motive driving force. 相似文献
50.
The level of substance-P-like immunoreactivity (SPLI) in dog paw lymph was determined before and after scalding injury of the paw. At basal conditions, no SPLI could be detected in the paw lymph. Scalding induced an immediate increase of the SPLI-levels. Within 5-10 min after the scalding injury the levels increased up to 28 fmol ml-1 and then gradually decreased within 30-90 min after the injury. It is suggested that scalding injury results in release of substance P from sensory nerve endings, and that this release may contribute to the inflammatory response to scalding injury and, possibly, also wound healing. 相似文献