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51.
Effect of chronic ethanol consumption on the expression of complement components and acute-phase proteins in liver 总被引:2,自引:0,他引:2
Bykov I Junnikkala S Pekna M Lindros KO Meri S 《Clinical immunology (Orlando, Fla.)》2007,124(2):213-220
The complement system can provoke but also participate in the repair of liver injury. Here we investigated by microarray analysis the effect of chronic ethanol consumption on hepatic mRNA expression of complement components and acute-phase proteins in complement C3-deficient (C3(-/-)) and wild-type (C3(+/+)) mice. Up-regulation by ethanol of factor B, C1qA-chain and clusterin but down-regulation of factor H, Masp-2, factor D and the terminal components C6, C8alpha and C9 was seen in both strains. Ethanol up-regulated C2 and down-regulated C4bp only in C3(+/+) mice, while in C3(-/-) mice up-regulation of C1qB-chain and vitronectin was observed. The expression of factor B, C6, C1qB and factor I was lower but that of factor D higher in C3(-/-) than in C3(+/+) mice. Ethanol induced mRNA synthesis of many acute-phase proteins including SPARC and lipocalin-2, but reduced the expression of SAP. The induction of early classical and alternative pathway components and suppression of terminal pathway components and soluble regulators may thus contribute to alcohol-induced liver injury. Lipocalin-2 and SPARC emerge as new candidate markers for early detection of liver damage. 相似文献
52.
Pulkkinen A Viitanen L Kareinen A Lehto S Vauhkonen I Laakso M 《Journal of molecular medicine (Berlin, Germany)》2000,78(7):372-379
The endothelial nitric oxide synthase (eNOS) gene is responsible for constitutive nitric oxide synthesis and arterial vasodilatation. Recently two polymorphisms, the 27-bp repeat sequence in intron 4 and the Glu298Asp substitution in exon 7 of the eNOS gene have been reported to be related to coronary heart disease (CHD). We screened these polymorphisms of the eNOS gene in 308 unrelated nondiabetic subjects with CHD, in 251 unrelated patients with type 2 diabetes with CHD, and in 110 randomly selected healthy subjects without CHD. The 4a and Asp298 allele frequencies of the eNOS gene were 0.19 and 0.36 in nondiabetic patients with CHD, 0.21 and 0.27 in type 2 diabetic patients with CHD, and 0.16 and 0.31 in nondiabetic subjects without CHD (n.s. between the groups). The Asp298 allele in exon 7 of the eNOS gene was not associated with elevated blood pressure in any of the study groups. Among type 2 diabetic patients with CHD the 4a allele in intron 4 of the eNOS gene was associated with elevated levels of systolic (P=0.035) and mean arterial blood pressure (P=0.040). In nondiabetic subjects these associations were not statistically significant. When all study groups were pooled in statistical analysis the 4a allele of the eNOS gene was associated with elevated diastolic (P=0.032) and mean (P=0.030) arterial blood pressure even after adjustment for confounding factors. We conclude that the 4a allele of the eNOS gene is not associated with CHD or type 2 diabetes, but that it is related to elevated blood pressure levels particularly among type 2 diabetic patients with CHD. 相似文献
53.
Mari Rehu Kari Punnonen Vaughn Ostland Seppo Heinonen Mark Westerman Kari Pulkki Ulla Sankilampi 《European journal of haematology》2010,85(4):345-352
Objectives: Hepcidin is the key regulator of iron homeostasis. The aims of this study were to determine serum hepcidin concentrations and reference ranges in pregnant women and cord blood of newborns at term and to evaluate the associations between hepcidin concentrations and iron status parameters. Methods: A total of 191 pregnant women–newborn pairs were studied in Kuopio University Hospital, Finland. The measured parameters were serum hepcidin, ferritin, transferrin receptor, transferrin saturation, red cell indices, and erythropoietin. Results: The hepcidin concentration in pregnant women was significantly lower than in cord blood at term [geometric mean concentration (GMC) (95% confidence intervals) in pregnant women 10.7 ng/mL (8.5–13.4 ng/mL) vs. GMC of cord blood hepcidin 69.3 ng/mL (55.3–86.8 ng/mL), P < 0.001, adjusted analysis of variance]. Hepcidin was undetectable in 12% of mothers. Hepcidin concentration in pregnant women was the lowest in those who had the lowest iron status. However, maternal hepcidin concentration was not associated with cord blood hepcidin or iron status markers. Hepcidin concentration in cord blood was associated with cord blood iron status, but not with maternal iron status. Conclusions: At term pregnancy, hepcidin concentrations are very low, allowing maximal availability of iron for the fetus. Maternal and cord blood hepcidin levels were independently associated with either maternal or cord blood iron status. 相似文献
54.
Merit Melin Hanna Jarva Lotta Siira Seppo Meri Helena Kyhty Merja Vkevinen 《Infection and immunity》2009,77(2):676-684
The polysaccharide capsule is a major virulence mechanism of Streptococcus pneumoniae, shielding the bacterium from phagocytes. Capsule types may differ in their abilities to resist immune defense. Antibody-mediated complement activation and opsonophagocytosis are crucial in protection against pneumococcus. Conjugate vaccine trials suggest imperfect protection against 19F. We have previously shown that significantly more anti-19F than anti-6B antibody is needed for killing in the opsonophagocytic assay (OPA). In this study, we explored whether the amount of C3 deposited on serotype 6B and 19F pneumococcal strains reflects their sensitivity to opsonophagocytosis. We compared clinical 6B and 19F nasopharyngeal, middle ear, and blood isolates as well as reference OPA strains (n = 16) for their sensitivity to opsonophagocytosis and C3 deposition. Sixfold anticapsular antibody concentrations were required for 50% opsonophagocytic killing of 19F compared to that of 6B strains. Serotype 19F was more resistant to C3 deposition than 6B. Complement deposition and opsonophagocytosis were dependent on the concentration of anticapsular antibodies. Differences between pneumococcal serotypes in antibody-mediated protection may partly be explained by the abilities of the capsules to resist complement deposition. These findings support previous studies suggesting that higher antibody concentrations to the capsular polysaccharide are needed for protection against disease caused by serotype 19F than that caused by 6B. 相似文献
55.
56.
Kati Pentti Marjo T. Tuppurainen Risto Honkanen Lorenzo Sandini Heikki Kröger Esko Alhava Seppo Saarikoski 《Maturitas》2009
Background
To analyse prospectively the effect of calcium or calcium + D supplementation on coronary heart disease (CHD) in 52–62-year-old women.Methods and results
10,555 52–62-year-old women from the population-based Kuopio Osteoporosis Risk Factor and Prevention Study (OSTPRE) who did not have CHD at baseline were followed for nearly 7 years in 1994–2001. Information about use of calcium supplements and health events was obtained from two repeated questionnaires in 1989 and 1994. Information about causes of death during the follow-up was obtained from the Statistics Finland. Information about CHD and other disease morbidity before and during the follow-up was obtained from the Registry of Specially Refunded Drugs of the Finnish Social Insurance Institution (SII). Cox's proportional-hazards models were used to estimate the risk of CHD morbidity related to the use of calcium supplements. At baseline, 2723 women reported current use of calcium or calcium + D supplementation. During the follow-up, CHD was diagnosed in 513 women. Compared to non-users of calcium/calcium + D supplements, the multivariate adjusted hazard ratio (HR) of CHD was 1.24 (95% CI 1.02–1.52) in women who used these supplements. The multivariate adjusted HR for CHD morbidity in postmenopausal women who used calcium/calcium + D supplements was 1.26 (95% CI 1.01–1.57).Conclusions
Calcium or calcium + D supplementation appears to increase the risk of CHD among women before old age. 相似文献57.
58.
Expression of vascular endothelial growth factor and vascular endothelial growth factor receptor-2 (KDR/Flk-1) in ischemic skeletal muscle and its regeneration 总被引:11,自引:0,他引:11 下载免费PDF全文
Rissanen TT Vajanto I Hiltunen MO Rutanen J Kettunen MI Niemi M Leppänen P Turunen MP Markkanen JE Arve K Alhava E Kauppinen RA Ylä-Herttuala S 《The American journal of pathology》2002,160(4):1393-1403
Vascular endothelial growth factor (VEGF) is a hypoxia-inducible endothelial cell mitogen and survival factor. Its receptor VEGFR-2 (KDR/Flk-1) mediates these effects. We studied the expression of VEGF and VEGFR-2 in ischemic human and rabbit skeletal muscle by immunohistochemistry and in situ hybridization. Human samples were obtained from eight lower limb amputations because of acute or chronic critical ischemia. In chronically ischemic human skeletal muscle VEGF and VEGFR-2 expression was restricted to atrophic and regenerating skeletal myocytes, whereas in acutely ischemic limbs VEGF and VEGFR-2 were expressed diffusely in the affected muscle. Hypoxia-inducible factor-1alpha was associated with VEGF and VEGFR-2 expression both in acute and chronic ischemia but not in regeneration. Hindlimb ischemia was induced in 20 New Zealand White rabbits by excising the femoral artery. Magnetic resonance imaging and histological sections revealed extensive ischemic damage in the thigh and leg muscles of ischemic rabbit hindlimbs with VEGF expression similar to acute human lower limb ischemia. After 1 and 3 weeks of ischemia VEGF expression was restricted to regenerating myotubes and by 6 weeks regeneration and expression of VEGF was diminished. VEGFR-2 expression was co-localized with VEGF expression in regenerating myotubes. Macrophages and an increased number of capillaries were associated with areas of ischemic muscle expressing VEGF and VEGFR-2. In conclusion, two patterns of VEGF and VEGFR-2 expression in human and rabbit ischemic skeletal muscle are demonstrated. In acute skeletal muscle ischemia VEGF and VEGFR-2 are expressed diffusely in the affected muscle. In chronic skeletal muscle ischemia and in skeletal muscle recovering from ischemia VEGF and VEGFR-2 expression are restricted to atrophic and regenerating muscle cells suggesting the operation of an autocrine pathway that may promote survival and regeneration of myocytes. 相似文献
59.
60.
Leo Syrjänen Tiina Luukkaala Mari Leppilampi Matti Kallioinen Silvia Pastorekova Jaromir Pastorek Abdul Waheed William S. Sly Seppo Parkkila Tuomo Karttunen 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2014,122(9):880-889
Purpose of the study was to evaluate the presence of hypoxia‐inducible, tumour‐associated carbonic anhydrases IX and XII in normal skin and a series of cutaneous tumours. Human tumour samples were taken during surgical operations performed on 245 patients and were immunohistochemically stained. A histological score value was calculated for statistical analyses which were performed using SPSS for Windows, versions 17.0 and 20.0. In normal skin, the highest expression of CA IX was detected in hair follicles, sebaceous glands, and basal parts of epidermis. CA XII was detected in all epithelial components of skin. Both CA IX and CA XII expression levels were significantly different in epidermal, appendigeal, and melanocytic tumour categories. Both CA IX and XII showed the most intense immunostaining in epidermal tumours, whereas virtually all melanocytic tumours were devoid of CA IX and XII immunostaining. In premalignant lesions, CA IX expression significantly increased when the tumours progressed to more severe dysplasia forms. Both CA IX and XII are highly expressed in different epithelial components of skin. They are also highly expressed in epidermal tumours, in which CA IX expression levels also correlate with the dysplasia grade. Interestingly, both isozymes are absent in melanocytic tumours. 相似文献