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41.
Differential macrophage expression of IL-12 and IL-23 upon innate immune activation defines rat autoimmune susceptibility 总被引:1,自引:0,他引:1
Andersson A Kokkola R Wefer J Erlandsson-Harris H Harris RA 《Journal of leukocyte biology》2004,76(6):1118-1124
Rodents typically demonstrate strain-specific susceptibilities to induced autoimmune models such as experimental arthritis and encephalomyelitis. A common feature of the local pathology of these diseases is an extensive infiltration of activated macrophages (MPhi). Different functional activation states can be induced in MPhi during innate immune activation, and it is this differential activation that might be important in susceptibility/resistance to induction or perpetuation of autoimmunity. In this study, we present an extensive, comparative analysis of the activation phenotypes of MPhi derived from autoimmune-susceptible and autoimmune-resistant rat strains to describe a cellular phenotype that defines the disease phenotype. We included investigation of receptor function, intracellular signaling pathways, cytokines, and other soluble mediators released after activation of cells using a panel of stimuli embracing many activation routes. We report that activation of MPhi from the autoimmune-susceptible strain was associated with alternative activation indicated by induction of arginase activity, a lower production of classical proinflammatory mediators, and a high production of interleukin (IL)-23, and MPhi from the autoimmune-resistant strains were associated with a higher production of proinflammatory mediators, a classical activation phenotype, and preferential induction of IL-12. These MPhi phenotypes thus reflect disparate, genetic cellular programs that define autoimmune susceptibility. 相似文献
42.
Although histochemical staining of the S100 protein family has been used for many years in the diagnosis of malignant melanoma, recent studies suggest one of the proteins comprising the S100 family, S100B, has particular utility in many aspects of the clinical management of malignant melanoma. This protein has been shown to be of use in staging malignant melanoma, in establishing prognosis, in evaluating treatment success and in predicting relapse. S100B is an independent prognostic factor and pretreatment circulating S100B concentrations predict duration of survival in melanoma patients. Survival is significantly longer in melanoma patients with normal S100B levels compared to those with elevated levels. Circulating S100B levels very sensitively detect metastatic growth of malignant melanoma, particularly in stage IV disease where S100B is certainly superior to other laboratory parameters. S100B concentrations reflect tumor mass. Serum S100B levels predict efficacy of treatment. Decreasing S100B concentrations reflect response to therapy while increasing S100B concentrations indicate tumor progression. Circulating S100B has a role to play in the decision to switch treatment regimens. 相似文献
43.
Summary.Background: Milk fermented with Lactobacillus
helveticus (L.
helveticus) has been shown to lower blood pressure
and to increase bone mineral content in spontaneously
hypertensive rats. The effect of L.helveticus may be due to better
calcium availability. Aim of the
study: In the present study the effect of milk fermented with
L. helveticus on acute
changes in calcium metabolism and bone resorption in
postmenopausal women was studied.Methods: The study was performed as a randomised double-blind
crossover study of 20 postmenopausal women (mean age 65, range
50–78). The study was carried out in two parts. Firstly,
L. helveticus fermented milk
was compared to a control milk. Secondly, juice containing
peptides formed with L.
helveticus bacteria was compared to a control juice.
The acute effect on calcium metabolism was measured during the
study day by serum ionised calcium (iCa), parathyroid hormone
(PTH), calcium (Ca), phosphate (P), and urinary calcium. A
direct marker of bone turnover, carboxyterminal telopeptide of
type I collagen (ICTP), was measured from the serum.Results: L. helveticus fermented
milk reduced serum PTH (405.3 ± 37 ng/l vs. 454.9 ± 37, p =
0.012) and increased serum calcium (19.1 ± 0.2 mmol/l vs. 18.8 ±
0.2, p = 0.031) compared to the control milk.
L. helveticus derived
peptides had no significant acute effect on calcium metabolism,
in fact, ionised calcium was lower and PTH higher after the
juice containing peptides compared to the control juice.Conclusions: Fermentation of milk with Lactobacillus helveticus had a positive
acute effect on calcium metabolism. This effect was not
explained by the small peptides formed by
L. helveticus. 相似文献
44.
Pellinen R Hakkarainen T Wahlfors T Tulimäki K Ketola A Tenhunen A Salonen T Wahlfors J 《International journal of oncology》2004,25(6):1753-1762
Lentiviruses have been used as gene transfer vectors for almost 10 years and their utility has been demonstrated in a variety of different applications. However, their value in cancer gene therapy has not been studied thoroughly. Here we show that VSV-G pseudotyped HIV-1-based lentiviruses are efficient vectors for human tumor cells in vitro and in vivo. Lentiviral gene transfer efficiency was demonstrated by transducing 42 different cell lines, representing 10 different human tumor types. It was shown that most of the cell lines were good or excellent targets for lentiviral transduction, allowing 50-95% gene transfer efficiency. These results were comparable to those obtained with an E1/E3 deleted, serotype 5 adenovirus vector. Analysis of lentivirus vector structure revealed that virus particles devoid of HIV-1 accessory proteins appeared to be more efficient, but the presence of enhancing elements cPPT and WPRE did not play a major role in transduction efficiency to four different human tumor cell lines. However, their effect on the gene expression level in these cells was apparent. To examine the impact of lentiviral gene expression level on suicide gene therapy approach, human osteosarcoma cells were transduced with lentivirus- or adenovirus vectors carrying the fusion gene HSV-TK-GFP and exposed to ganciclovir. Cell viability analysis after the treatment revealed that both vector types induced similar level of cytotoxicity, suggesting that lentiviral expression of a suicide gene is adequate for tumor cell destruction. Finally, in vivo transduction studies with subcutaneous tumors showed that lentivirus vectors can yield similar gene transfer efficiency than adenovirus vector, despite three orders of magnitude lower titer of the lentiviral preparation. In conclusion, these data show that lentiviruses are efficient gene transfer vehicles for human tumor cells and justify their use in further preclinical cancer gene therapy studies. 相似文献
45.
Ahola T Lapatto R Raivio KO Selander B Stigson L Jonsson B Jonsbo F Esberg G Stövring S Kjartansson S Stiris T Lossius K Virkola K Fellman V 《The Journal of pediatrics》2003,143(6):713-719
OBJECTIVE: To evaluate whether N-acetylcysteine (NAC) infusion during the first week of life reduces the risk of death or bronchopulmonary dysplasia (BPD) in infants with extremely low birth weight.Study design In a Nordic multicenter, double-blind trial, infants (n=391) weighing 500 to 999 g and on ventilator or nasal continuous positive airway pressure were randomized before the age of 36 hours to receive NAC 16 to 32 mg/kg/d (n=194) or placebo (n=197) intravenously for 6 days. Primary end points were death or BPD, defined as supplementary oxygen requirement at 36 weeks' gestational age. RESULTS: There was no difference in the combined incidence of the primary end points death or BPD, 51% vs. 49%, between the NAC group and control group. Also similar was the incidence of BPD in survivors at 36 weeks' gestational age, 40% vs. 40%, and the mean oxygen requirement at the age of 28 days, 31.2% vs. 30.7%, respectively. The severity of BPD was similar in both groups. CONCLUSIONS: A 6-day course of intravenous N-acetylcysteine at the dosage used does not prevent BPD or death in infants with extremely low birth weight. 相似文献
46.
Sandberg S McCann DC Ahola S Oja H Paton JY McGuinness D 《Acta paediatrica (Oslo, Norway : 1992)》2002,91(2):152-158
Ninety children aged 6 to 13 y and suffering from chronic asthma were included in a prospective follow-up study lasting 18 mo in order to assess whether life events involving substantial positive effects on the child can protect against the increased risk associated with stressful life events. The main outcome measures included positive life events, positive long-term experiences, severely negative life events, chronic psychosocial stress and new asthma exacerbation. The results showed that, provided they occurred in close proximity to severely negative life events, positive life events, generally related to the child's own achievements, afforded protection against the increased risk of a new asthma exacerbation precipitated by severe events in children whose lives were marked by low to medium levels of chronic stress. No such effect was found in children exposed to high chronic stress nor did long-term positive experiences, such as when the child has a rewarding hobby, affect the asthma risk.
Conclusion : Life events with a definite positive effect can counteract the increased risk of an asthma exacerbation precipitated by a severely negative life event, provided the chronic stress is only of low to medium level. Because this protective influence does not apply where there is high chronic stress, reducing this condition must be seen as a priority in children suffering from asthma, as these children are also more vulnerable to negative life events precipitating asthma exacerbation. 相似文献
Conclusion : Life events with a definite positive effect can counteract the increased risk of an asthma exacerbation precipitated by a severely negative life event, provided the chronic stress is only of low to medium level. Because this protective influence does not apply where there is high chronic stress, reducing this condition must be seen as a priority in children suffering from asthma, as these children are also more vulnerable to negative life events precipitating asthma exacerbation. 相似文献
47.
Ihalin R Pienihäkkinen K Lenander M Tenovuo J Jousimies-Somer H 《International journal of antimicrobial agents》2003,21(5):434-440
Actinobacillus actinomycetemcomitans has an important aetiological role in localized juvenile periodontitis and in progressive periodontitis in adults. A. actinomycetemcomitans is found mainly in periodontal pockets but also in whole saliva, a potential transmission medium. It is sensitive to peroxidase-halide systems, but the differences between periodontitis associated clinical isolates and type strains are unclear. The sensitivities of these 2 strain groups to lactoperoxidase (LP)-iodide (I(-))-hydrogen peroxide (H(2)O(2)) combinations were investigated, and the sensitivities were compared with the susceptibilities to four antibiotics. There was great variation between the sensitivities of different strains, but the 2 strain groups responded similarly. The LP (75 microg)-I(-) (100 nmol)-H(2)O(2) (1000 nmol) combination produced a similar degree of inhibition as 2 microg ampicillin. The LP-I(-) system might be a potential antimicrobial agent against A. actinomycetemcomitans transmission via saliva. 相似文献
48.
Linnola RJ Sund M Ylönen R Pihlajaniemi T 《Journal of cataract and refractive surgery》2003,29(1):146-152
PURPOSE: To evaluate soluble fibronectin, vitronectin, and collagen type IV adhesion to poly(methyl methacrylate) (PMMA), fluorine-surface-modified PMMA, silicone, hydrophobic and hydrophilic acrylate, and hydrogel intraocular lenses (IOLs) and determine whether hydrophobic and hydrophilic acrylate materials have different fibronectin-adhesion properties. SETTING: Department of Medical Biochemistry, University of Oulu, Oulu, Finland. METHODS: One hundred fifty IOLs were incubated for 1 week at 37 degrees C with radioactive-iodine-labeled soluble fibronectin, vitronectin, or collagen type IV. Fifty IOLs were analyzed for each protein, 5 from each of 10 different IOL models (PMMA, Alcon MC60BM; fluorine-surface-modified PMMA, Chiron Fluorilens Centra-55F; silicone, Allergan Medical Optics SI-40NB and Pharmacia and Upjohn CeeOn 911A; hydrophobic soft acrylate, Alcon AcrySof MA60BM and SA30AL and AMO Sensar; hydrophilic soft acrylate, Ioltech Stabibag and Bausch and Lomb BL27; and hydrogel, Bausch and Lomb Hydroview. The amount of adherent protein was measured with a gamma counter at 1 and 7 days and expressed as counts per minute. RESULTS: At 1 week, significantly more fibronectin was bound to the hydrophobic acrylate IOLs than to the 2-hydroxyethyl methacrylate (HEMA) containing hydrophilic acrylate IOLs (P <.05 to.0001). Significantly more vitronectin was bound to the 2 silicone IOLs than to any other IOL (P <.01 to.0001) at 7 days. Collagen type IV adhered best to the hydrophilic acrylate IOLs, which were significantly different (P <.01 to.0001) than the other IOLs at 1 and 7 days. CONCLUSIONS: Each IOL material had a different affinity to each protein. Significant binding to 1 protein does not indicate that the IOL will bind significantly to all proteins; instead, each protein should be studied separately. Fibronectin bound significantly better to hydrophobic acrylate IOLs than to hydrophilic acrylate IOLs, suggesting that the HEMA-containing IOLs should be classified with the hydrogel IOL group. 相似文献
49.
Kyrolainen H Kivela R Koskinen S McBride J Andersen JL Takala T Sipila S Komi PV 《Medicine and science in sports and exercise》2003,35(1):45-49
PURPOSE: The present study was designed to investigate possible differences in running economy (RE) among elite middle-distance runners by examining muscle structure and maximal isometric force (MVC). METHODS: Ten young male runners ran at six different running speeds. During the running bouts, respiratory gases, and blood lactate were measured. Muscle biopsies were obtained from the vastus lateralis muscle for analyzing fiber type distribution, muscle fiber area, myosin heavy chain (MHC) composition, activities of a number of metabolic enzymes (citrate synthase, lactate dehydrogenase, phosphofruktokinase, and 3-hydroxyacyl-CoA-dehydrogenase), and titin isoforms. RESULTS: Energy expenditure (EE) increased linearly up to the speed of 6.0 m.s. The relative distribution of the MHC isoforms was MHC I: 67.0%, MHC IIA: 31.5%, and MHC IIX: 1.5%. The present results demonstrated that higher the area of Type II fibers, higher the MVC (r = 0.59, P< 0.05). The amount of MHC II correlated inversely with EE when running close to the competition speed (r = -0.61, P< 0.05). Enzyme activities did not correlate significantly with either RE or EE. Titin analysis revealed that a faster-mobility titin band was observed in all subjects, whereas a lower-mobility titin band was observed only in the most economical runner. CONCLUSION: Differences in RE among homogeneous group of middle-distance runners were observed at various running speeds. This may partly be explained by differences in muscle fiber distribution, MHC composition, and titin isoforms. 相似文献
50.
The results of several randomized studies have verified the efficacy of 10 mg mifepristone in emergency contraception. In the present study we characterized the pharmacokinetics of 10 mg mifepristone. Eight healthy female volunteers received a single oral dose of mifepristone on the day 10 or 11 of their menstrual cycle. Blood samples were collected at 0, 1, 2, 4 and 8 h, daily for the next 6 days and on day 10 after mifepristone. Mifepristone concentrations were determined by radioimmunoassay preceded by column chromatography. A peak level of 1.41 ± 0.31 μmol/L (mean ± SD) was measured at 1 h. Individual elimination phase half-lives varied from 15.3 to 26.8 h, the mean (± SD) value being 19.6 ± 4.50 h. Serum mifepristone concentrations exceeded 10 nmol/L in all volunteers for an average of 4.9 days. The pharmacokinetic data on 10 mg mifepristone are in line with previous pharmacokinetic and clinical data, and encourage further development of the 10-mg dose in emergency contraception. 相似文献