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41.
Pleuropulmonary blastoma (PPB) is a rare, aggressive, intrathoracic mesenchymal neoplasm associated with cystic lung lesions. The authors describe an 8-month-old male who underwent thoracoscopic left upper lobectomy for a cystic lung lesion initially diagnosed as congenital pulmonary airway malformation. Pathology revealed type I PPB.  相似文献   
42.
Inflammation can predispose to myocardial infarction (MI), and mannan binding lectin (MBL) promotes phagocytic clearance of inflammatory agents, but the predictive value of MBL levels for MI is not known. MBL was analyzed in subgroups of the population-based Reykjavik study, a cohort of 19,381 participants recruited from 1967. MBL levels were very stable over time (self correlation: 0.86). In a cross-sectional group from the original cohort (n = 987), high MBL (>1,000 microg/L) was associated with a greatly lowered odds ratio for MI (0.64, P < 0.001). To verify this finding, a nested case control sample (n = 1,309) was randomly selected from the cohort. High MBL at recruitment was also associated with decreased MI risk in this follow-up group, but to a lesser extent and not significant for the whole group, smokers, or hypertensive individuals. However, high MBL was as in the cross-sectional group, associated with greatly decreased MI risk in diabetic (P = 0.02) or hypercholesterolemic individuals (P = 0.004). This also applied to raised erythrocyte sedimentation rate (P = 0.007). Diabetic patients with high MBL did not have a higher MI risk than nondiabetic individuals. Our findings indicate that high MBL may predict decreased likelihood of MI, particularly in diabetics, and are consistent with the possibility that MBL may promote clearance of atherogenic agents.  相似文献   
43.

Summary

The incidence of the most common fracture types in Iceland is reported based on individual data from the Reykjavik Study 1967–2008. Time trend is reported for the major osteoporotic fractures (MOS) 1989–2008.

Introduction

This study aims to assess the incidence of all fractures in Iceland, with emphasis on the rate of hip fractures, and compare the incidence with other populations as well as examine the secular changes.

Methods

Individuals from the prospective population-based cohort Reykjavik Study were examined between 1967 and 2008 (follow-up 26.5 years), which consisted of 9,116 men and 9,756 women born in 1907–1935, with age range 31–81 years. First fracture incidence was estimated using life table methods with age as the timescale.

Results

Fracture rate increased proportionally with age between the sexes for vertebral and proximal humerus but disproportionally for hip and distal forearm fractures. The ratio of first fracture incidence between the sexes varied considerably by site: 2.65 for hip fractures and the highest for distal forearm fractures at 4.83. By the age of 75, 36.7 % of women and 21 % of men had sustained a fracture, taking into account competing risk of death. The incidence of hip fractures was similar to results previously published from USA, Sweden, Norway, and Scotland. The incidence of MOS fractures in both sexes decreased over the last decade, except hip fractures in men, which remained unchanged, as reflected in the women/men ratio for the hip, which changed from 2.6 to 1.7.

Conclusion

This study adds information to scarce knowledge on the relative fracture incidence of different fractures. The incidence of MOS fractures increased in the latter part of the last century in both sexes and declined during the last decade, less dramatically for men. This information is important for planning health resources.  相似文献   
44.

Summary

Association between serum bone formation and resorption markers and cortical and trabecular bone loss and the concurrent periosteal apposition in a population-based cohort of 1069 older adults was assessed. BTM levels moderately reflect the cellular events at the endosteal and periosteal surfaces but are not associated with fracture risk.

Introduction

We assessed whether circulating bone formation and resorption markers (BTM) were individual predictors for trabecular and cortical bone loss, periosteal expansion, and fracture risk in older adults aged 66 to 93 years from the AGES-Reykjavik study.

Methods

The sample for the quantitative computed tomography (QCT)-derived cortical and trabecular BMD and periosteal expansion analysis consisted of 1069 participants (474 men and 595 women) who had complete baseline (2002 to 2006) and follow-up (2007 to 2011) hip QCT scans and serum baseline BTM. During the median follow-up of 11.7 years (range 5.4–12.5), 54 (11.4 %) men and 182 (30.6 %) women sustained at least one fracture of any type.

Results

Increase in BTM levels was associated with faster cortical and trabecular bone loss at the femoral neck and proximal femur in men and women. Higher BTM levels were positively related with periosteal expansion rate at the femoral neck in men. Markers were not associated with fracture risk.

Conclusion

This data corroborates the notion from few previous studies that both envelopes are metabolically active and that BTM levels may moderately reflect the cellular events at the endosteal and periosteal surfaces. However, our results do not support the routine use of BTM to assess fracture risk in older men and women. In light of these findings, further studies are justified to examine whether systemic markers of bone turnover might prove useful in monitoring skeletal remodeling events and the effects of current osteoporosis drugs at the periosteum.
  相似文献   
45.
Low birth weight has consistently been associated with increased adult blood pressure. The relative importance of childhood growth is, however, less well established. This study examined sex-specific associations between childhood growth and adult blood pressure in 2120 subjects born from 1921 to 1935 in Reykjavik who were recruited into a longitudinal study in 1967-1991. Size at birth and growth at regular intervals between 8 and 13 years were collected from national archives. Hypertensive males did not differ from normotensive males at birth but were increasingly taller and of higher body mass index between 8 and 13 years. No differences in adult height were observed between hypertensive and normotensive males. For boys, growth-velocity (change in growth per year) for body mass index and height between 8 to 13 years was positively associated (P<0.05) with adult blood pressure. The association for body mass index-velocity was fully accounted for by concurrent body size, whereas height-velocity was independent of birth weight and concurrent body size. Males in the highest compared with the lowest tertile in the height-velocity distribution had 66% increased risks of hypertension (95% CI: 15% to 139% increased risks of hypertension) corresponding with 5.0 mm Hg increase (95% CI: 1.5 to 8.5 mm Hg increase) and 3.1 mm Hg increase (95% CI: 1.1 to 5.0 mm Hg increase) in systolic and diastolic blood pressures, respectively. Hypertensive females weighed less at birth but did not differ markedly from normotensive girls between 8 and 13 years, and no association was observed for growth-velocity. In conclusion, rapid linear growth between 8 and 13 years predicts elevated adult blood pressure in boys. This association is likely to reflect relatively early onset of puberty among hypertensive males.  相似文献   
46.
Imaging studies have reported conflicting findings on how brain structure differs with age and sex. This may be explained by discrepancies and limitations in study population and study design. We report a study on brain tissue volumes in one of the largest cohorts of individuals studied to date of subjects with high mean age (mean ± standard deviation (SD) 76 ± 6 years). These analyses are based on magnetic resonance imaging (MRI) scans acquired at baseline on 4303 non-demented elderly, and 367 who had a second MRI, on average 2.5 ± 0.2 years later. Tissue segmentation was performed with an automatic image analysis pipeline. Total brain parenchymal (TBP) volume decreased with increasing age while there was an increase in white matter hyperintensities (WMH) in both sexes. A reduction in both normal white matter (NWM)- and gray matter (GM) volume contributed to the brain shrinkage. After adjusting for intra-cranial volume, women had larger brain volumes compared to men (3.32%, p < 0.001) for TBP volume in the cross-sectional analysis. The longitudinal analysis showed a significant age-sex interaction in TBP volume with a greater rate of annual change in men (− 0.70%, 95%CI: − 0.78% to − 0.63%) than women (− 0.55%, 95%CI: − 0.61% to − 0.49%). The annual change in the cross-sectional data was approximately 40% less than the annual change in the longitudinal data and did not show significant age-sex interaction. The findings indicate that the cross-sectional data underestimate the rate of change in tissue volumes with age as the longitudinal data show greater rate of change in tissue volumes with age for all tissues.  相似文献   
47.
48.
49.
Monocyte chemotactic protein-1 (MCP-1) and its receptor CCR2 may play a role in mediating atherosclerosis. The polymorphisms MCP-1 -2518A>G and CCR2 190G>A have been reported to be associated with increased risk for developing atherosclerosis. The aim of this study was to investigate the effect of these polymorphisms and the MCP-1 -2076A>T polymorphism on the development of myocardial infarction (MI) in an Icelandic cohort. Four hundred and sixty MI survivors and 1842 disease free controls were genotyped. No significant difference in the frequencies of any of the polymorphisms between the cases and the controls was found, with OR=0.87 (95% CI 0.71-1.08) for MCP-1 -2518G, OR=1.05 (95% CI 0.84-1.33) for MCP-1 -2076T and OR=0.93 (95% CI 0.71-1.23) for CCR2 190A. An effect of an OR for MI of 1.4 for the MCP-1 -2518G, MCP-1 -2076T and CCR2 190A alleles could be detected in a cohort of the size of this study with power=0.8 and alpha=0.05. In our cohort we were unable to demonstrate a significant association of the MCP-1 -2518A>G, MCP-1 -2076A>T or CCR2 190G>A polymorphisms with MI. These results do not support the extent of risk associated with developing MI previously reported for the CCR2 190 and MCP-1 -2518 polymorphisms.  相似文献   
50.
Chen Z  Aspelund A  Jin H 《Vaccine》2008,26(3):361-371
The currently circulating influenza B viruses from both antigenic lineages contain an N-linked glycosylation site in the hemagglutinin (HA) protein at positions of 196 or 197. However, egg adaptation caused the loss of the glycosylation site that could impact virus antigenicity and vaccine efficacy. The effect of the 196/197 glycosylation site on influenza B virus growth and antigenicity was systemically evaluated in this study by the molecular approach. Paired recombinant 6:2 reassortant influenza B vaccine strains, with or without the 196/197 glycosylation site, were generated by reverse genetics and the glycosylation site was retained in MDCK cells. In contrast, all the viruses that contained the introduced glycosylation site were unable to grow in eggs and rapidly lost the glycosylation site once adapted to grow in eggs. We showed that glycosylation affected virus binding to the alpha-2,3-linked sialic acid receptor and affected virus antigenicity as tested by postinfected ferret sera. We have further identified that the Arginine residue at amino acid position 141 (141R) can stabilize the 196/197 glycosylation site without affecting virus antigenicity. Thus, the 141R could be introduced into vaccine strains to retain the 196/197 glycosylation site for influenza B vaccines.  相似文献   
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