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排序方式: 共有273条查询结果,搜索用时 15 毫秒
91.
Pussinen PJ Jauhiainen M Vilkuna-Rautiainen T Sundvall J Vesanen M Mattila K Palosuo T Alfthan G Asikainen S 《Journal of lipid research》2004,45(1):139-147
Periodontitis, a consequence of persistent bacterial infection and chronic inflammation, has been suggested to predict coronary heart disease (CHD). The aim of this study was to investigate the impact of periodontitis on HDL structure and antiatherogenic function in cholesterol efflux in vitro. HDL was isolated from 30 patients (age 43.6 +/- 6.1 years, mean +/- SD) with periodontitis before and after (3.2 +/- 1.4 months) periodontal treatment. The capacity of HDL for cholesterol efflux from macrophages (RAW 264.7), HDL composition, and key proteins of HDL metabolism were determined. After periodontal treatment, phospholipid transfer protein (PLTP) activity was 6.2% (P<0.05) lower, and serum HDL cholesterol concentration, PLTP mass, and cholesteryl ester transfer protein activity were 10.7% (P<0.001), 7.1% (P=0.078), and 19.4% (P<0.001) higher, respectively. The mean HDL2/HDL3 ratio increased from 2.16 +/- 0.87 to 3.56 +/- 0.48 (P<0.05). HDL total phospholipid mass and sphingomyelin-phosphatidylcholine ratio were 7.4% (P<0.05) and 36.8% (P<0.001) higher, respectively. The HDL-mediated cholesterol efflux tended to be higher after periodontal treatment; interestingly, this increase was significant (P<0.05) among patients whose C-reactive protein decreased (53.7% reduction, P=0.015) and who were positive by PCR for Actinobacillus actinomycetemcomitans. These results suggest that periodontitis causes similar, but milder, changes in HDL metabolism than those that occur during the acute-phase response and that periodontitis may diminish the antiatherogenic potency of HDL, thus increasing the risk for CHD. 相似文献
92.
We studied inbreeding depression in a perennial plant, Lychnis viscaria, in three populations differing in their inbreeding history and population size by measuring several traits at two nutrient levels over the plant's life cycle. The observed levels of inbreeding depression (cumulative inbreeding depression, from -0.057 to 0.629) were high for a plant with a mixed mating system. As expected, the population with a low level of isozyme variation expressed the least inbreeding depression for seed germination. Highest inbreeding depression for germination was found in the largest and genetically most variable population. No clear differences between populations in expression of inbreeding depression in the later life stages were found. The population level inbreeding depression varied with the nutrient conditions and among populations and life stages, but we found no evidence that inbreeding depression increased with lower nutrient availability. These results emphasize the importance of measuring inbreeding depression under several environmental conditions and over life stages. 相似文献
93.
The multisubunit enzyme V-ATPase harbours isoforms of individual subunits. a3 is one of four 116 kDa subunit a isoforms, and it is crucial for bone resorption. We used small interfering RNA (siRNA) molecules to knock down a3 in rat osteoclast cultures. Labeled siRNA-molecules entered osteoclasts via endocytosis and knocked down the a3 mRNA. Bone resorption was decreased in siRNA-treated samples due to decreased acidification and osteoclast inactivation. Expression of a1 did not respond to decreased a3 levels, suggesting that a1 does not compensate for a3 in osteoclast cultures. Subunit a3 is thus an interesting target for novel nucleic acid therapy. 相似文献
94.
Strong hyaluronan expression in the full-thickness rat articular cartilage repair tissue 总被引:2,自引:0,他引:2
Lammi PE Lammi MJ Tammi RH Helminen HJ Espanha MM 《Histochemistry and cell biology》2001,115(4):301-308
Articular cartilage lesions have a poor capacity to regenerate. In full-depth articular cartilage defects, the repair process involves an ingrowth of mesenchymal cells from the bone marrow to the injured area, and these cells attempt to restore the lesion with cartilage-like repair tissue. In this study, we investigated histologically the distribution of hyaluronan in the rat repair tissue in relation to other glycosaminoglycans. Full-depth lesions were drilled to the weight-bearing region of rat medical femoral condyle. The rats were divided into two groups: intermittent active motion (IAM) and running training (RT) groups. In the RT group, programmed exercise was started 1 week after surgery, while the rats in the IAM group could move freely in their cages. The lesions were investigated 4 and 8 weeks after the surgery. Semiquantitative histological grading showed no significant differences in the repair between the groups. In normal articular cartilage, hyaluronan was stained mainly around chondrocytes. During repair, strong hyaluronan staining was observed in loose mesenchymal tissue, while in the repair area undergoing endochondral ossification, hyaluronan was intensively stained mainly around the hypertrophic chondrocytes. Remarkably strong staining for hyaluronan was noticed in areas of apparent mesenchymal progenitor cell invasion, the areas being simultaneously devoid of staining for keratan sulphate. In conclusion, hyaluronan is strongly expressed in the early cartilage repair tissue, and its staining intensity and distribution shows very sensitively abnormal articular cartilage structure. 相似文献
95.
96.
Pirkko Hämeenoja 《Acta veterinaria Scandinavica》2002,43(Z1):S33
Requirements of the organic pig farming create an opportunity to offer good life for animals. The space requirements give animals the possibility to exhibit species-specific behavior and provide them opportunity for more exercise. Bedding and roughage are important in helping to reduce production stress. The most difficult question in a veterinary point of view is how to manage the animal health care. Vaccinations, antibiotics and anthelmintic can be used in organic production but only in a limited way. A lot can be achieved with good management but there are still situations when the use of medicine is necessary. What is the amount of joint inflammations or liver spots to justify the use of medicine? The question has to be solved case by case. The profitability of the production is a crucial point in an organic farm because a poor economy is a great threat to animal welfare. 相似文献
97.
Mikael Kyrklund Heidi Kaski Ramin Akhi Antti E Nissinen Outi Kummu Ulrich Bergmann Pirkko Pussinen Sohvi Hrkk Chunguang Wang 《Innate immunity》2021,27(2):158
Natural Abs are produced by B lymphocytes in the absence of external Ag stimulation. They recognise self, altered self and foreign Ags, comprising an important first-line defence against invading pathogens and serving as innate recognition receptors for tissue homeostasis. Natural IgG Abs have been found in newborns and uninfected individuals. Yet, their physiological role remains unclear. Previously, no natural IgG Abs to oxidation-specific epitopes have been reported. Here, we show the cloning and characterisation of mouse IgG mAbs against malondialdehyde acetaldehyde (MAA)-modified low-density lipoprotein. Sequence analysis reveals high homology with germline genes, suggesting that they are natural. Further investigation shows that the MAA-specific natural IgG Abs cross-react with the major periodontal pathogen Porphyromonas gingivalis and recognise its principle virulence factors gingipain Kgp and long fimbriae. The study provides evidence that natural IgGs may play an important role in innate immune defence and in regulation of tissue homeostasis by recognising and removing invading pathogens and/or modified self-Ags, thus being involved in the development of periodontitis and atherosclerosis. 相似文献
98.
Pöllänen E Sipilä S Alen M Ronkainen PH Ankarberg-Lindgren C Puolakka J Suominen H Hämäläinen E Turpeinen U Konttinen YT Kovanen V 《Aging cell》2011,10(4):650-660
Aging is associated with gradual decline of skeletal muscle strength and mass often leading to diminished muscle quality. This phenomenon is known as sarcopenia and affects about 30% of the over 60-year-old population. Androgens act as anabolic agents regulating muscle mass and improving muscle performance. The role of female sex steroids as well as the ability of skeletal muscle tissue to locally produce sex steroids has been less extensively studied. We show that despite the extensive systemic deficit of sex steroid hormones in postmenopausal compared to premenopausal women, the hormone content of skeletal muscle does not follow the same trend. In contrast to the systemic levels, muscle tissue of post- and premenopausal women had similar concentrations of dehydroepiandrosterone and androstenedione, while the concentrations of estradiol and testosterone were significantly higher in muscle of the postmenopausal women. The presence of steroidogenetic enzymes in muscle tissue indicates that the elevated postmenopausal steroid levels in skeletal muscle are because of local steroidogenesis. The circulating sex steroids were associated with better muscle quality while the muscle concentrations reflected the amount of infiltrated fat within muscle tissue. We conclude that systemically delivered and peripherally produced sex steroids have distinct roles in the regulation of neuromuscular characteristics during aging. 相似文献
99.
Tina Suominen P?ivi Uutela Raimo A. Ketola Jonas Bergquist Lars Hillered Moshe Finel Hongbo Zhang Aki Laakso Risto Kostiainen 《PloS one》2013,8(6)
An UPLC-MS/MS method was developed for the determination of serotonin (5-HT), dopamine (DA), their phase I metabolites 5-HIAA, DOPAC and HVA, and their sulfate and glucuronide conjugates in human brain microdialysis samples obtained from two patients with acute brain injuries, ventricular cerebrospinal fluid (CSF) samples obtained from four patients with obstructive hydrocephalus, and a lumbar CSF sample pooled mainly from patients undergoing spinal anesthesia in preparation for orthopedic surgery. The method was validated by determining the limits of detection and quantification, linearity, repeatability and specificity. The direct method enabled the analysis of the intact phase II metabolites of 5-HT and DA, without hydrolysis of the conjugates. The method also enabled the analysis of the regioisomers of the conjugates, and several intact glucuronide and sulfate conjugates were identified and quantified for the first time in the human brain microdialysis and CSF samples. We were able to show the presence of 5-HIAA sulfate, and that dopamine-3-O-sulfate predominates over dopamine-4-O-sulfate in the human brain. The quantitative results suggest that sulfonation is a more important phase II metabolism pathway than glucuronidation in the human brain. 相似文献
100.
Azharuddin Sajid Syed Khaja Nishtman Dizeyi Pradeep Kumar Kopparapu Lola Anagnostaki Pirkko H?rk?nen Jenny Liao Persson 《PloS one》2013,8(8)
Alterations in cellular pathways related to both endocrine and vascular endothelial growth factors (VEGF) may contribute to breast cancer progression. Inhibition of the elevated levels of these pathways is associated with clinical benefits. However, molecular mechanisms by which endocrine-related pathways and VEGF signalling cooperatively promote breast cancer progression remain poorly understood. In the present study, we show that the A-type cyclin, cyclin A1, known for its important role in the initiation of leukemia and prostate cancer metastasis, is highly expressed in primary breast cancer specimens and metastatic lesions, in contrasting to its barely detectable expression in normal human breast tissues. There is a statistically significant correlation between cyclin A1 and VEGF expression in breast cancer specimens from two patient cohorts (p<0.01). Induction of cyclin A1 overexpression in breast cancer cell line MCF-7 results in an enhanced invasiveness and a concomitant increase in VEGF expression. In addition, there is a formation of protein–protein complexes between cyclin A1 and estrogen receptor ER-α cyclin A1 overexpression increases ER-α expression in MCF-7 and T47D cells. In mouse tumor xenograft models in which mice were implanted with MCF-7 cells that overexpressed cyclin A1 or control vector, cyclin A1 overexpression results in an increase in tumor growth and angiogenesis, which is coincident with an enhanced expression of VEGF, VEGFR1 and ER-α Our findings unravel a novel role for cyclin A1 in growth and progression of breast cancer, and suggest that multiple cellular pathways, including cell cycle regulators, angiogenesis and estrogen receptor signalling, may cooperatively contribute to breast cancer progression. 相似文献