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1.
Why is the age-standardized incidence of low-trauma fractures rising in many elderly populations? 总被引:4,自引:0,他引:4
Pekka Kannus Seppo Niemi Jari Parkkari Mika Palvanen Ari Heinonen Harri Siev?nen Teppo J?rvinen Karim Khan Markku J?rvinen 《Journal of bone and mineral research》2002,17(8):1363-1367
Low-trauma fractures of elderly people are a major public health burden worldwide, and as the number and mean age of older adults in the population continue to increase, the number of fractures is also likely to increase. Epidemiologically, however, an additional concern is that, for unknown reasons, the age-standardized incidence (average individual risk) of fracture has also risen in many populations during the recent decades. Possible reasons for this rise include a birth cohort effect, deterioration in the average bone strength by time, and increased average risk of (serious) falls. Literature provides evidence that the rise is not due to a birth cohort effect, whereas no study shows whether bone fragility has increased during this relatively short period of time. This osteoporosis hypothesis could, however, be tested if researchers would now repeat the population measurements of bone mass and density that were made in the late 1980s and the 1990s. If such studies proved that women's and men's age-standardized mean values of bone mass and density have declined over time, the osteoporosis hypothesis would receive scientific support. The third explanation is based on the hypothesis that the number and/or severity of falls has risen in elderly populations during the recent decades. Although no study has directly tested this hypothesis, a great deal of indirect epidemiologic evidence supports this contention. For example, the age-standardized incidence of fall-induced severe head injuries, bruises and contusions, and joint distortions and dislocations has increased among elderly people similarly to the low-trauma fractures. The fall hypothesis could also be tested in the coming years because the 1990s saw many research teams reporting age- and sex-specific incidences of falling for elderly populations, and the same could be done now to provide data comparing the current incidence rates of falls with the earlier ones. 相似文献
2.
Seppo W. Langer 《Current oncology reports》2010,12(4):242-246
Extravasation of chemotherapy is a feared complication of anticancer therapy. The accidental leakage of cytostatic agents
into the perivascular tissues may have devastating short-term and long-term consequences for patients. In recent years, the
increased focus on chemotherapy extravasation has led to the development of international guidelines that have proven useful
tools in daily clinical practice. Moreover, the tissue destruction in one of the most dreaded types of extravasation (ie,
anthracycline extravasation) now can effectively be prevented with a specific antidote, dexrazoxane. 相似文献
3.
Markku Leino MD Kalevi Pyörälä Seppo Lehto Arto Rantala 《Documenta ophthalmologica. Advances in ophthalmology》1992,80(4):309-315
Lens opacity studies were performed using an electronic Lens Opacity Meter (Interzeag Opacity Lensmeter 701) in a population (n = 321) with ischaemic heart disease. These patients are participating in a trial targetting at the reduction of mortality and incidence of myocardial infarction using a cholesterol-lowering drug, simvastatin. A separate study to evaluate the reliability of the method showed good reproducibility. Repeated measurements after a short time-interval (2–10 days) gave statistically lower opacity values either due to a change in lens transparency or perhaps a change in pigment and cell dispersion in the acqueous caused by repeated mydriasis. Lens opacity values showed a highly significant positive correlation to age. Serum cholesterol, systolic blood pressure and smoking habits showed no significant correlations to the levels of lens opacity when adjustments for age were made.Abbreviations HMG-CoA
hydroxy-methylglutarylcoenzyme A
- 4S
Scandinavian Simvastatin Survival Study
- LOM
lens opacity meter 相似文献
4.
Petru Liuba Jerker Persson Jukka Luoma Seppo Yl?-Herttuala Erkki Pesonen 《European heart journal》2003,24(6):515-521
BACKGROUND: Atherosclerosis begins early in life. Infections might contribute to the pathogenesis of atherosclerosis. In this study, we investigated whether acute infections in children could alter the carotid wall morphology and the lipid profile. METHODS: Mean carotid intima-media thickness (IMT) was measured by high-resolution ultrasound in 28 hospitalised children (mean age: 5+/-2 years), who fulfilled the diagnostic criteria of acute infections (body temperature, >38 degrees C; C-reactive protein, >15mg/ml, and clinical), and in 20 age- and gender-matched controls. Antibodies against oxidised low-density lipoprotein (anti-oxLDL antibodies), as well as total and high-density lipoprotein cholesterol (HDL-C) were analysed in all children. The infection group was investigated both during the acute illness and 3 months after clinical recovery (post-infection). RESULTS: During the acute illness, the infection group had elevated anti-oxLDL antibodies and decreased HDL-C, as compared to those obtained at 3 months and in controls (p<0.05). These changes in the infection group were followed, at 3 months, by thickening of carotid intima-media. Those who received antibiotics during their acute illness had less carotid thickening than those who were not treated with antibiotics (p<0.05). CONCLUSION: Acute infections in children seem to be accompanied by enhanced oxidative modification of LDL and by decrease in HDL-C. These lipid changes may be followed by thickening of carotid artery intima-media. These findings suggest that, in childhood, acute infections could be associated with increased risk of atherosclerosis, and warrant further studies on this topic. 相似文献
5.
6.
Complement-mediated lysis of cancer cells growing in three-dimensional aggregates involves factors that are not associated with the killing of cells in suspension. We have used multicellular tumor spheroids established from breast carcinoma (T47D) and ovarian teratocarcinoma (PA-1) cell lines as models to study complement-mediated destruction of micrometastases and small solid tumors. We found that significant killing of microtumors treated with an antitumor antibody and a specific monoclonal antibody (YTH53.1) against the complement lysis inhibitor protectin (CD59) started to occur after a 1 to 2-hour lag phase. After an overnight incubation, the microtumors became totally infiltrated by the YTH53.1 monoclonal antibody and C1q, whereas C3 and C5b-9 penetrated as a frontier to the peripheral cell layers. A 51Cr release assay showed that during a 24-hour pulsed treatment with complement, 33% of cells in the spheroids were killed, and the average tumor volume decreased by 28%. According to propidium iodide staining, complement exposure resulted in killing and peeling off of the outermost tumor cells. 相似文献
7.
Itälä A Koort J Ylänen HO Hupa M Aro HT 《Journal of biomedical materials research. Part A》2003,67(2):496-503
A novel chemical etching method was recently developed to create a controlled microrough surface on porous bioactive glass implants. Our earlier in vitro studies showed enhanced attachment of osteoblast-like MG63 cells on a microrough bioactive glass surface. The purpose of our current study was to confirm the in vivo significance of surface microroughening for bone bonding of bioactive glass. Porous bioactive glass cones made of sintered microspheres were surgically implanted in the anterior cortex of rabbit femurs. Peripheral quantitative computed tomography (pQCT), biomechanical push-out testing, histomorphometry, and electron microscopy (BEI-SEM) were used to analyze bone ingrowth and osseointegration at 7, 10, 14, 28, 56, and 84 days after implantation. The results showed that microroughening of the bioactive glass surface significantly enhanced the bone-bonding response of the biomaterial. The positive response was seen in one of the three bioactive glass compositions studied. The affinity index of new bone on the glass surface was significantly (p = 0.02) increased with a trend (p = 0.10) toward improved mechanical incorporation. New bone formation was dependent on the glass composition, and it was found to occur not only through the mechanism of bone ingrowth but also based on in situ osteogenesis within implant interstices. Based on these results, the procedure of microroughening could enhance the osteopromotive properties of certain bioactive glass compositions. 相似文献
8.
Akbar F Heinonen S Pirskanen M Uimari P Tuomainen TP Salonen JT 《Molecular human reproduction》2005,11(1):73-77
Association between pre-eclampsia (PEE1) and the dimethylarginine dimethylaminohydrolase (DDAH) 1 and 2 genes, which play a role in the regulation of nitric oxide synthesis and release, was studied. In a case-control study design single nucleotide polymorphisms (SNPs) were determined at eight sites in the DDAH1 gene and at one site (Pro231Pro) in the DDAH2 gene from 132 women with pre-eclampsia and 112 healthy controls. Three SNPs in the DDAH1 gene were associated with pre-eclampsia, showing complete linkage disequilibrium with each other, but none of the associations in the allele or genotype data reached statistical significance in either of the genes after the correction for multiple testing. Haplotype frequencies were estimated using a population based on a maximum likelihood method (EM algorithm). Four common DDAH1 haplotypes were present and a significant association of haplotypes H2 and H3 with pre-eclampsia (P=0.03) was found. The risk of pre-eclampsia was greatest in individuals (odds ratio: 3.93; 95% confidence interval: 1.54-9.99) who had two copies of the high-risk haplotypes (H2 or H3). The observed haplotypic association provides the first evidence of the importance of DDAH1 polymorphisms in pre-eclampsia susceptibility. 相似文献
9.
Pekka Oja Raija M. T. Laukkanen T. Katriina Kukkonen-Harjula Ilkka M. Vuori Matti E. Pasanen Seppo P. T. Niittymäki Tiina Solakivi 《European journal of applied physiology》1991,62(6):400-404
Summary Two experiments were carried out to compare the cardiorespiratory and metabolic effects of cross-country skiing and running training during two successive winters. Forty-year-old men were randomly assigned into skiing (n = 15 in study 1,n = 16 in study 2), running (n = 16 in study 1 andn = 16 in study 2) and control (n = 17 in study 1 andn = 16 in study 2) groups. Three subjects dropped out of the programme. The training lasted 9–10 weeks with 40-min exercise sessions three times each week. The training intensity was controlled at 75%–85% of the maximal oxygen consumption (VO2max) using portable heart rate metres and the mean heart rate was 156–157 beats·min–1 in the training groups. In the pooled data of the two studies the mean increase in theVO2max (in ml·min–1·kg–1) on a cycle ergometer was 17% for the skiing group, 13% for the running group and 2% for the control group. The increase inVO2max was highly significant in the combined exercise group compared to the control group but did not differ significantly between the skiing and running groups. The fasting serum concentrations of lipoproteins and insulin did not change significantly in any of the groups. These results suggested that training by cross-country skiing and running of the same duration and intensity at each session for 9–10 weeks improved equally the cardiorespiratory fitness of untrained middle-aged men. 相似文献
10.
Acquired Resistance of Escherichia coli to Complement Lysis by Binding of Glycophosphoinositol-Anchored Protectin (CD59)
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Riina Rautemaa Gary A. Jarvis Pertti Marnila Seppo Meri 《Infection and immunity》1998,66(5):1928-1933
Protectin (CD59) is a glycophosphoinsitol (GPI)-anchored defender of human cells against lysis by the membrane attack complex of complement. In this study, we examined whether protectin released from human cell membranes can incorporate into the surface of gram-negative bacteria. Analysis by using radiolabeled protectin, immunofluorescence, flow cytometry, and whole-cell enzyme-linked immunosorbent assay demonstrated that protectin bound to nonencapsulated Escherichia coli EH237 (Re) and EH234 (Ra) in a calcium-dependent manner. The incorporation required the GPI-phospholipid moiety since no binding of a phospholipid-free soluble form of protectin was observed. Mg2+ did not enhance the binding, and a polysialic acid capsule prevented it (strain IH3080 [O18:K1:H8]). Bound protectin inhibited the C5b-9 neoantigen expression on complement-treated bacteria. Protection against complement lysis was observed in both a colony counting assay and a bioluminescence assay, where viable EH234 bacteria expressing the luciferase gene emitted green light in the presence of the luciferine substrate. In general, two- to four-times-higher serum concentrations were needed to obtain 50% lysis of protectin-coated versus noncoated bacteria. The results indicate that protectin can incorporate in a functionally active form into the cell membranes of the two nonencapsulated deep rough E. coli strains studied. 相似文献