| 1. |
- Bravo, L, et al.
(author)
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- 2021
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swepub:Mat__t
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| 2. |
- Tabiri, S, et al.
(author)
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- 2021
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swepub:Mat__t
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| 3. |
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| 4. |
- Jiang, Jieying, et al.
(author)
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Association of genetic variations in aromatase gene with serum estrogen and estrogen/testosterone ratio in Chinese elderly men.
- 2010
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In: Clinica chimica acta. - : Elsevier BV. - 1873-3492 .- 0009-8981. ; 411:1-2, s. 53-8
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Journal article (peer-reviewed)abstract
- BACKGROUND: Single nucleotide polymorphism (SNP) rs2470152 of the gene CYP19A1 is associated with serum estradiol (E2) levels in Caucasian men. However, it remains to be verified if rs2470152 is the sole determinant accounting for the association. We determined whether 2 CYP19A1 SNPs tagging different haploblocks (rs2470152 and rs2899470) are associated with sex steroid levels in Chinese men. METHOD: Serum sex steroid level including E2, estrone (E1) and testosterone (T), of 1402 Chinese men aged > or = 65 years were analyzed. Genotyping of the two CYP19A1 SNPs was performed using Tm-shift allele-specific PCR. RESULTS: SNP rs2899470 was significantly associated with serum E2, E1 levels and E2/T ratio (p<0.001). However, SNP rs2470152 was only modestly associated with E2/T ratio (p=0.023). Analysis of haplotype showed a significant association between C-G, T-T haplotype with serum E2/T ratio (p=0.019 and p=1 x 10(-5), respectively). Similarly, E2 levels was also associated the T-T and T-G haplotypes (p=1 x 10(-5)). CONCLUSION: The genetic variation of CYP19A1 was associated with circulating estrogen levels in Chinese elderly men. In addition, it revealed that haplotype of rs2899470 and rs2470152, rather than rs2899470 alone, was a better indicator for the serum E2/T ratio and E2 levels.
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| 5. |
- Jiang, Jieying, et al.
(author)
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Association of SRD5A2 variants and serum androstane-3alpha,17beta-diol glucuronide concentration in Chinese elderly men.
- 2010
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In: Clinical chemistry. - : Oxford University Press (OUP). - 1530-8561 .- 0009-9147. ; 56:11, s. 1742-9
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Journal article (peer-reviewed)abstract
- Results of recent studies have demonstrated that genetic variants of the enzyme steroid 5α reductase type II (SRD5A2) are associated with serum concentrations of major androgen metabolites such as conjugates of androstane-3α,17β-diol-glucuronide (3α-diol-G). However, this association was not consistently found among different ethnic groups. Thus, we aimed to determine whether the association with SRD5A2 genetic variations exists in a cohort of healthy Chinese elderly men, by examining 2 metabolite conjugates: androstane-3α,l7β-diol-3-glucuronide (3α-diol-3G) and androstane-3α,17β-diol-17-glucuronide (3α-diol-17G).
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| 6. |
- Styrkarsdottir, Unnur, et al.
(author)
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GWAS of bone size yields twelve loci that also affect height, BMD, osteoarthritis or fractures
- 2019
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In: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 10:1
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Journal article (peer-reviewed)abstract
- Bone area is one measure of bone size that is easily derived from dual-energy X-ray absorptiometry (DXA) scans. In a GWA study of DXA bone area of the hip and lumbar spine (N ≥ 28,954), we find thirteen independent association signals at twelve loci that replicate in samples of European and East Asian descent (N = 13,608 – 21,277). Eight DXA area loci associate with osteoarthritis, including rs143384 in GDF5 and a missense variant in COL11A1 (rs3753841). The strongest DXA area association is with rs11614913[T] in the microRNA MIR196A2 gene that associates with lumbar spine area (P = 2.3 × 10 −42 , β = −0.090) and confers risk of hip fracture (P = 1.0 × 10 −8 , OR = 1.11). We demonstrate that the risk allele is less efficient in repressing miR-196a-5p target genes. We also show that the DXA area measure contributes to the risk of hip fracture independent of bone density.
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| 7. |
- Wong, Samuel Y S, et al.
(author)
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Low DHEAS levels are associated with depressive symptoms in elderly Chinese men: results from a large study.
- 2011
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In: Asian journal of andrology. - : Medknow. - 1745-7262 .- 1008-682X. ; 13:6, s. 898-902
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Journal article (peer-reviewed)abstract
- This study investigated the association between depressive symptoms in elderly Chinese men and the total testosterone, dehydroepiandrosterone (DHEA), DHEA sulphate (DHEAS), oestradiol and sex hormone-binding globulin (SHBG) levels, and the free androgen index. Cross-sectional data from 1147 community-dwelling elderly men, aged 65 and older, were used. Depressive symptoms were measured using the Chinese Geriatric Depression Scale (GDS). Total testosterone, free testosterone, DHEA, DHEAS, total oestradiol, the free androgen index and SHBG levels were assessed. DHEA was significantly associated with GDS score, and there was a trend towards DHEAS association, but this was not significant (β=-0.110, P=0.015; β=-0.074, P=0.055). However, no association was seen between depressive symptoms and total testosterone levels, free testosterone levels, oestradiol levels or SHBG levels. In terms of the presence of clinically relevant depressive symptoms, there were no statistically significant differences between patients in the lowest quartile of sex steroid hormone levels and those in other quartiles of sex steroid hormone levels. Similarly to Western studies, our study shows that DHEA and DHEAS levels are associated with depressive symptoms.
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| 8. |
- Thomas, HS, et al.
(author)
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- 2019
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swepub:Mat__t
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| 9. |
- Auyeung, T. W., et al.
(author)
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Sleep Duration and Disturbances Were Associated With Testosterone Level, Muscle Mass, and Muscle Strength-A Cross-Sectional Study in 1274 Older Men
- 2015
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In: Journal of the American Medical Directors Association. - : Elsevier BV. - 1525-8610. ; 16:7
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Journal article (peer-reviewed)abstract
- Background: Testosterone level follows a circadian rhythm. However, whether sleep duration and disturbances can affect testosterone level, muscle mass, and strength remains unknown. Objective: To examine the relationship of sleep duration and disturbances to testosterone level, muscle mass, muscle strength, and walking speed. Participants and methods: We recruited 1274 community-dwelling men older than 65 years of age. Their early morning testosterone level was assayed by mass spectrometry. A sleep questionnaire was administered to enquire about their reported sleep duration, prolonged sleep latency (>0.5 hour), and subjective insomnia complaint. Muscle mass was measured by dual-energy x-ray absorptiometry. Testosterone level, muscle mass, handgrip strength, and walking speed were tested against sleep duration and disturbances. Results: Testosterone increased with increasing sleep duration up to 9.9 hours, after which it decreased, giving rise to an inverted U-shaped relationship (P for quadratic trend < .05). A similar inverted U-shaped relationship occurred between sleep duration and muscle mass and function. Earlier go-to-bed time, despite being associated with a higher testosterone level (P < .05), was associated with weaker grip strength (P < .05). Earlier wake-up time was associated with higher muscle mass (P < .05) but neither grip strength nor walking speed. Neither prolonged sleep latency nor insomnia was associated with testosterone levels. However, prolonged sleep latency was associated with lower muscle mass (P < .05), weaker grip strength (P < .05), and slower walking speed (P < .001). Insomnia, on the other hand was associated with weaker grip strength (P < .05) and slower walking speed (P < .001) but not muscle mass. Conclusions: Sleep duration and disturbances can affect testosterone level, muscle mass, and its function. Whether optimization of sleep can ameliorate age-associated decline in sex hormone and muscle performance warrants further studies. (C) 2015 AMDA - The Society for Post-Acute and Long-Term Care Medicine.
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| 10. |
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| 11. |
- Bundred, Nigel J, et al.
(author)
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Cyclooxygenase-2 inhibition does not improve the reduction in ductal carcinoma in situ proliferation with aromatase inhibitor therapy: results of the ERISAC randomized placebo-controlled trial.
- 2010
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In: Clinical cancer research : an official journal of the American Association for Cancer Research. - 1078-0432. ; 16:5, s. 1605-12
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Journal article (peer-reviewed)abstract
- Tamoxifen reduces risk of recurrence after breast conservation surgery for ductal carcinoma in situ (DCIS), but no data exists on the effectiveness of aromatase inhibitors for DCIS. Cyclooxygenase-2 (COX-2) is overexpressed in DCIS, representing another potential therapeutic target. The aim of the study was to determine the effect of aromatase and/or COX-2 inhibition on epithelial proliferation and apoptosis in a presurgical study of estrogen receptor (ER)-positive DCIS. Methods: Postmenopausal women with ER-positive DCIS diagnosed by core biopsy were randomized to a 2 x 2 design of either 14 days of exemestane or placebo and celecoxib, or placebo immediately before surgery. Paired baseline and end point biopsies were analyzed for proliferation (Ki67), apoptosis, human epidermal growth factor receptor 2 (HER2), COX-2, and progesterone receptor (PR) expression by immunohistochemistry. The primary end point was a decrease in Ki67 between diagnosis and surgical excision.
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| 12. |
- Chan, Ruth, et al.
(author)
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Association between serum 25-hydroxyvitamin D and psychological health in older Chinese men in a cohort study.
- 2011
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In: Journal of affective disorders. - : Elsevier BV. - 1573-2517 .- 0165-0327. ; 130:1-2, s. 251-259
-
Journal article (peer-reviewed)abstract
- BACKGROUND: Few studies evaluated the association between vitamin D and psychological health in Chinese. This study examined these associations in Chinese older men in Hong Kong. METHODS: Baseline serum 25-hydroxyvitamin D (25OHD), depression and cognitive function were assessed in 939 community-dwelling Chinese men aged >65. Data on depression status at 4-year follow up was available in 629 men. Data were collected for confounding factors: demographics, number of diseases, smoking, alcohol use, body mass index, physical activity, mobility limitations, dietary intake, season of blood measurement, and serum parathyroid hormone level. Multivariate logistic regression analyses were performed with adjustments for confounding factors. RESULTS: An inverse association between serum 25OHD and baseline depression was observed. Men in the highest (>=92nmol/L) compared with lowest (<=63nmol/L) quartile of serum 25OHD had an adjusted odds ratio for depression of 0.46 (95% CI: 0.22-0.98, P(trend)=0.004). The association was more pronounced in low vitamin D season than in high vitamin D season. No association was observed between serum 25OHD and incident depression at 4years. Baseline cognitive impairment was not associated with serum 25OHD in all models. LIMITATIONS: Self-reported measure of depression and cognitive performance, the small number of incident depression at 4-year follow up and selection bias may affect the study validity. CONCLUSIONS: Serum 25OHD was inversely associated with depression at baseline and was not linked to baseline cognitive impairment and 4-year incident depression in Chinese older men. Future studies are warranted to evaluate these associations in populations with higher prevalence of vitamin D deficiency.
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| 13. |
- Chan, Ruth, et al.
(author)
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Not All Elderly People Benefit From Vitamin D Supplementation with Respect to Physical Function: Results From the Osteoporotic Fractures in Men Study, Hong Kong.
- 2012
-
In: Journal of the American Geriatrics Society. - : Wiley. - 1532-5415 .- 0002-8614. ; 60:2, s. 290-295
-
Journal article (peer-reviewed)abstract
- OBJECTIVES: To examine vitamin D status and its association with physical performance and muscle mass in older Chinese men. DESIGN: Cross-sectional and prospective cohort study design. SETTING: Hong Kong, People's of Republic of China. PARTICIPANTS: Nine hundred thirty-nine community-dwelling men aged 65 and older for cross-sectional analysis and 714 for longitudinal analysis. MEASUREMENTS: Baseline serum 25-hydroxyvitamin D (25OHD) was measured using a competitive radioimmunoassay kit. Baseline and 4-year physical performance measures (grip strength, 6-m walking speed, step length in a 6-m walk, time to complete five chair stands) were measured, and appendicular skeletal muscle mass (ASM) was assessed using dual-energy X-ray absorptiometry. Data were collected for confounding factors: demographic, number of diseases, smoking, alcohol use, body mass index, physical activity, diet, season of blood sampling, and serum parathyroid hormone (PTH) level. Multivariate regression analyses were performed with adjustments for confounding factors. RESULTS: Mean±standard deviation serum 25OHD level of this sample of Chinese community-dwelling older men who had a high level of baseline physical function was 77.9±20.5nmol/L; 94.1% of participants had serum 25OHD levels of 50nmol/L or greater. Median (interquartile range) serum PTH level was 4.1pmol/L (3.1-5.5pmol/L). After adjustment for potential confounding factors, serum 25OHD levels were not associated with baseline or 4-year change in physical performance measures and ASM. CONCLUSION: In Chinese older men who are vitamin D replete and have a high level of baseline physical function, vitamin D may not have an important role in physical function and muscle mass.
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| 14. |
- Chan, R, et al.
(author)
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Serum 25-hydroxyvitamin D and parathyroid hormone levels in relation to blood pressure in a cross-sectional study in older Chinese men.
- 2012
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In: Journal of human hypertension. - : Springer Science and Business Media LLC. - 1476-5527 .- 0950-9240. ; 26:1, s. 20-27
-
Journal article (peer-reviewed)abstract
- Vitamin D status, parathyroid hormone (PTH) level and their associations with blood pressure in Chinese population are unknown. This study examined these associations in older Chinese men. Blood pressure, serum 25-hydroxyvitamin D (25OHD) and PTH was measured in 939 community-dwelling Chinese men aged 65 years and older. Linear regression analyses were performed with adjustments for age, body mass index, education, season of measurement, medication use, self-reported history of stroke and Parkinson's disease, and other lifestyle factors. In either crude or adjusted models, serum 25OHD was not associated with blood pressure, whereas increasing PTH levels was associated with higher blood pressure. Men in the highest quartile of serum PTH level had a mean difference of 3.4mmHg and 2.8mmHg higher in as systolic blood pressure (SBP) and diastolic blood pressure (DBP), respectively, than men in the lowest quartile of serum PTH level (P(trend)=0.019 for SBP and <0.001 for DBP). In conclusion, the findings support an association between serum PTH and blood pressure, but not for serum 25OHD in older Chinese men whose vitamin D status is optimal. The lack of association between serum 25OHD and blood pressure may possibly because of the relatively high serum 25OHD levels of the study sample.
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| 15. |
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| 16. |
- Cossarizza, A., et al.
(author)
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Guidelines for the use of flow cytometry and cell sorting in immunological studies (second edition)
- 2019
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In: European Journal of Immunology. - : Wiley. - 0014-2980 .- 1521-4141. ; 49:10, s. 1457-1973
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Journal article (peer-reviewed)abstract
- These guidelines are a consensus work of a considerable number of members of the immunology and flow cytometry community. They provide the theory and key practical aspects of flow cytometry enabling immunologists to avoid the common errors that often undermine immunological data. Notably, there are comprehensive sections of all major immune cell types with helpful Tables detailing phenotypes in murine and human cells. The latest flow cytometry techniques and applications are also described, featuring examples of the data that can be generated and, importantly, how the data can be analysed. Furthermore, there are sections detailing tips, tricks and pitfalls to avoid, all written and peer-reviewed by leading experts in the field, making this an essential research companion.
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| 17. |
- Dong, Guangzhong, et al.
(author)
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Active Balancing of Lithium-Ion Batteries Using Graph Theory and A-Star Search Algorithm
- 2021
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In: IEEE Transactions on Industrial Informatics. - 1941-0050 .- 1551-3203. ; 17:4, s. 2587-2599
-
Journal article (peer-reviewed)abstract
- The heterogeneity of cells in a battery pack is inevitable but brings high risks of premature failure and even safety hazards. Accordingly, for safe and long-life operation, it is necessary to adjust the state of charge (SOC) of all in-pack cells to the same level. To address this problem, this article first proposes a battery SOC observer and analyzes its stability and convergence analysis using the Lyapunov direct method. Different to most available estimators is that the proposed method does not require the information of cell capacities. Then, after modeling the equalization system as a directed graph, the equalization problem is cast as a path searching problem. Finally, an A-star algorithm subject to balancing constraints is proposed to find the shortest path in this graph, corresponding to the most efficient SOC equalization. Experimental results show that the steady-state error of the proposed observer is less than 2%. It also demonstrates that the A-star algorithm can decrease the balancing time and energy loss during the balancing process by 9.59% and 19.5%, respectively, relative to the mean-difference-average method.
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| 18. |
- Drake, TM, et al.
(author)
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Surgical site infection after gastrointestinal surgery in children: an international, multicentre, prospective cohort study
- 2020
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In: BMJ global health. - : BMJ. - 2059-7908. ; 5:12
-
Journal article (peer-reviewed)abstract
- Surgical site infection (SSI) is one of the most common healthcare-associated infections (HAIs). However, there is a lack of data available about SSI in children worldwide, especially from low-income and middle-income countries. This study aimed to estimate the incidence of SSI in children and associations between SSI and morbidity across human development settings.MethodsA multicentre, international, prospective, validated cohort study of children aged under 16 years undergoing clean-contaminated, contaminated or dirty gastrointestinal surgery. Any hospital in the world providing paediatric surgery was eligible to contribute data between January and July 2016. The primary outcome was the incidence of SSI by 30 days. Relationships between explanatory variables and SSI were examined using multilevel logistic regression. Countries were stratified into high development, middle development and low development groups using the United Nations Human Development Index (HDI).ResultsOf 1159 children across 181 hospitals in 51 countries, 523 (45·1%) children were from high HDI, 397 (34·2%) from middle HDI and 239 (20·6%) from low HDI countries. The 30-day SSI rate was 6.3% (33/523) in high HDI, 12·8% (51/397) in middle HDI and 24·7% (59/239) in low HDI countries. SSI was associated with higher incidence of 30-day mortality, intervention, organ-space infection and other HAIs, with the highest rates seen in low HDI countries. Median length of stay in patients who had an SSI was longer (7.0 days), compared with 3.0 days in patients who did not have an SSI. Use of laparoscopy was associated with significantly lower SSI rates, even after accounting for HDI.ConclusionThe odds of SSI in children is nearly four times greater in low HDI compared with high HDI countries. Policies to reduce SSI should be prioritised as part of the wider global agenda.
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| 19. |
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| 20. |
- Grundberg, Elin, et al.
(author)
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Vitamin D receptor 3' haplotypes are unequally expressed in primary human bone cells and associated with increased fracture risk: the MrOS Study in Sweden and Hong Kong.
- 2007
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In: Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research. - : Wiley. - 0884-0431. ; 22:6, s. 832-40
-
Journal article (peer-reviewed)abstract
- The VDR is a prime candidate gene for osteoporosis. Here, we studied three common VDR haplotypes in relation to bone phenotypes in 5014 participants of the global MrOS Study. We also studied the relative expression of the haplotypes in human bone cells. One haplotype was associated with increased fracture risk and differently expressed in primary human bone cells. INTRODUCTION: Vitamin D plays an essential role in skeletal metabolism by binding to its nuclear steroid receptor, the vitamin D receptor (VDR). The heritability of BMD is well established, and the VDR gene is considered a prime candidate suggested to partially account for genetically controlled BMD variance in the population. MATERIALS AND METHODS: Here, we reconstructed common haplotypes in the VDR 3' untranslated region (UTR) and studied the association to BMD and risk of vertebral fractures in elderly men from Sweden (n = 3014) and Hong Kong (n = 2000), all participants of the global MrOS Study. To assess any functional implications of the VDR polymorphisms, we studied allele-specific expressions of the different VDR 3' UTR haplotypes in the normal chromosomal context of 70 unrelated human trabecular bone samples. This was performed by quantitative genotyping of coding polymorphisms in RNA samples and in corresponding DNA samples isolated from the bone samples. RESULTS: Three major haplotypes were reconstructed and in agreement with the previously well-defined baT, BAt, and bAT haplotypes, herein denoted Hap1, Hap2, and Hap3. The Hap1 haplotype was independently associated with increased risk of vertebral fractures in Swedish men (OR, 1.655; 95% CI, 1.146-2.391; p < 0.01) and with lower lumbar spine BMD in elderly men from Sweden (p < 0.01) and Hong Kong (p < 0.05). The VDR gene was also shown to exhibit a 3' UTR haplotype dependent allelic imbalance, indicating that the VDR Hap1 allele was overexpressed in human trabecular bone samples. CONCLUSIONS: The results indicate that the relatively overexpressed VDR Hap1 haplotype could be considered a risk allele for osteoporosis regardless of ethnicity.
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| 21. |
- Grundberg, Elin, et al.
(author)
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Vitamin D receptor 3 ' haplotypes are unequally expressed in primary human bone cells and associated with increased fracture risk: The MrOS study in Sweden and Hong kong
- 2007
-
In: Journal of Bone and Mineral Research. - : Wiley. - 1523-4681 .- 0884-0431. ; 22:6, s. 832-840
-
Journal article (peer-reviewed)abstract
- The VDR is a prime candidate gene for osteoporosis. Here, we studied three common VDR haplotypes in relation to bone phenotypes in 5014 participants of the global MrOS Study. We also studied the relative expression of the haplotypes in human bone cells. One haplotype was associated with increased fracture risk and differently expressed in primary human bone cells. Introduction: Vitamin D plays an essential role in skeletal metabolism by binding to its nuclear steroid receptor, the vitamin D receptor (VDR). The heritability of BMD is well established, and the VDR gene is considered a prime candidate suggested to partially account for genetically controlled BMD variance in the population. Materials and Methods: Here, we reconstructed common haplotypes in the VDR 3 ' untranslated region (UTR) and studied the association to BMD and risk of vertebral fractures in elderly men from Sweden (n = 3014) and Hong Kong (n = 2000), all participants of the global MrOS Study. To assess any functional implications of the VDR polymorphisms, we studied allele-specific expressions of the different VDR 3 ' UTR haplotypes in the normal chromosomal context of 70 unrelated human trabecular bone samples. This was performed by quantitative genotyping of coding polymorphisms in RNA samples and in corresponding DNA samples isolated from the bone samples. Results: Three major haplotypes were reconstructed and in agreement with the previously well-defined baT, BAt, and bAT haplotypes, herein denoted Hap1, Hap2, and Hap3. The Hap1 haplotype was independently associated with increased risk of vertebral fractures in Swedish men (OR, 1.655; 95% Cl, 1.146-2.391;p < 0.01) and with lower lumbar spine BMD in elderly men from Sweden (p < 0.01) and Hong Kong (P < 0.05). The VDR gene was also shown to exhibit a 3 ' UTR haplotype dependent allelic imbalance, indicating that the VDR Hap1 allele was overexpressed in human trabecular bone samples. Conclusions: The results indicate that the relatively overexpressed VDR Hap1 haplotype could be considered a risk allele for osteoporosis regardless of ethnicity.
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| 22. |
- Hammaréus, Filip, 1998-, et al.
(author)
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Plasma type I collagen α1 chain in relation to coronary artery disease : findings from a prospective population-based cohort and an acute myocardial infarction prospective cohort in Sweden.
- 2023
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In: BMJ Open. - : BMJ Publishing Group Ltd. - 2044-6055. ; 13:9
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Journal article (peer-reviewed)abstract
- OBJECTIVES: To investigate the association between type I collagen α1 chain (COL1α1) levels and coronary artery disease (CAD) by using absolute quantification in plasma. Also, to investigate the correlates of COL1α1 to clinical characteristics and circulating markers of collagen metabolism.DESIGN: Life conditions, Stress and Health (LSH) study: prospective cohort study, here with a nested case-control design.Assessing Platelet Activity in Coronary Heart Disease (APACHE) study: prospective cohort study.SETTING: LSH: primary care setting, southeast Sweden.APACHE: cardiology department, university hospital, southeast Sweden.PARTICIPANTS: LSH: 1007 randomly recruited individuals aged 45-69 (50% women). Exclusion criteria was serious disease. After 13 years of follow-up, 86 cases with primary endpoint were identified and sex-matched/age-matched to 184 controls.APACHE: 125 patients with myocardial infarction (MI), 73 with ST-elevation MI and 52 with non-ST-elevation MI.EXCLUSION CRITERIA: Intervention study participation, warfarin treatment and short life expectancy.PRIMARY AND SECONDARY OUTCOME MEASURES: Primary outcome was the association between baseline COL1α1 and first-time major event of CAD, defined as fatal/non-fatal MI or coronary revascularisation after 13 years. Secondary outcomes were the association between the collagen biomarkers PRO-C1 (N-terminal pro-peptide of type I collagen)/C1M (matrix metalloproteinase-mediated degradation of type I collagen) and CAD; temporal change of COL1α1 after acute MI up to 6 months and lastly, correlates between COL1α1 and patient characteristics along with circulating markers of collagen metabolism.RESULTS: COL1α1 levels were associated with CAD, both unadjusted (HR=0.69, 95% CI=0.56 to 0.87) and adjusted (HR=0.55, 95% CI=0.41 to 0.75). PRO-C1 was associated with CAD, unadjusted (HR=0.62, 95% CI=0.47 to 0.82) and adjusted (HR=0.61, 95% CI=0.43 to 0.86), while C1M was not. In patients with MI, COL1α1 remained unchanged up to 6 months. COL1α1 was correlated to PRO-C1, but not to C1M.CONCLUSIONS: Plasma COL1α1 was independently and inversely associated with CAD. Furthermore, COL1α1 appeared to reflect collagen synthesis but not degradation. Future studies are needed to confirm whether COL1α1 is a clinically useful biomarker of CAD.
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| 23. |
- Ho, Hung Chak, et al.
(author)
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“Planned greenspace” or “natural greenspace” in a high-density city with compact environment? An empirical study of osteoporosis among senior population
- 2022
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In: Building and Environment. - : Elsevier. - 0360-1323 .- 1873-684X. ; 219
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Journal article (peer-reviewed)abstract
- Osteoporosis is a major physical health issue in healthy ageing among urban populations. However, few studies have investigated how greenspace can influence osteoporosis, especially to those who lived in a compact city with high-density living environment. Furthermore, no studies have investigated how “planned greenspace” and “natural greenspace” can separately influence osteoporosis among senior population. We hereby conducted an empirical study to evaluate the relationship between osteoporosis, “planned greenspace” and “natural greenspace”, based on the use of land use data derived from local geospatial information and satellite images. Our results showed that seniors who were 1) aged, 2) female, 3) less educated, 4) smokers, and 5) with chronic respiratory diseases were associated with osteoporosis. Considering factors of greenspace, a higher percentage of planned greenspace surrounding the residence may be a protective factor while natural greenspace did not influence the individuals. Specifically, a 10% increase of planned greenspace within the 600-m radius area surrounding the residence was negative associated with osteoporosis (−2.8% [-5.1%, −0.5%]). Based on our results, development of planned greenspace may be necessary, as compact built environment of a high-density city often resulted in a lack of planned greenspace for physical activities. Along with the World Health Organization (WHO) guidelines for an age-friendly city, our findings suggest that improving the planned greenspace in a walkable distance around one's neighboring environment is a potential strategy for prevention of osteoporosis and related physical health issues as well as for life quality improvement among the senior population.
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| 24. |
- Hu, Xiping, et al.
(author)
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SAfeDJ : A crowd-cloud codesign approach to situation-aware music delivery for drivers
- 2015
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In: ACM Transactions on Multimedia Computing, Communications, and Applications (TOMCCAP). - : Association for Computing Machinery (ACM). - 1551-6857 .- 1551-6865. ; 12:1s, s. 21:1-24
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Journal article (peer-reviewed)abstract
- Driving is an integral part of our everyday lives, but it is also a time when people are uniquely vulnerable. Previous research has demonstrated that not only does listening to suitable music while driving not impair driving performance, but it could lead to an improved mood and a more relaxed body state, which could improve driving performance and promote safe driving significantly. In this article, we propose SAfeDJ, a smartphone-based situation-aware music recommendation system, which is designed to turn driving into a safe and enjoyable experience. SAfeDJ aims at helping drivers to diminish fatigue and negative emotion. Its design is based on novel interactive methods, which enable in-car smartphones to orchestrate multiple sources of sensing data and the drivers' social context, in collaboration with cloud computing to form a seamless crowdsensing solution. This solution enables different smartphones to collaboratively recommend preferable music to drivers according to each driver's specific situations in an automated and intelligent manner. Practical experiments of SAfeDJ have proved its effectiveness in music-mood analysis, and mood-fatigue detections of drivers with reasonable computation and communication overheads on smartphones. Also, our user studies have demonstrated that SAfeDJ helps to decrease fatigue degree and negative mood degree of drivers by 49.09% and 36.35%, respectively, compared to traditional smartphone-based music player under similar driving situations.
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| 25. |
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| 26. |
- Karlsson, Magnus, et al.
(author)
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Inferior physical performance tests in 10,998 men in the MrOS study is associated with recurrent falls
- 2012
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In: Age and Ageing. - : Oxford University Press (OUP). - 0002-0729 .- 1468-2834. ; 41:6, s. 740-746
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Journal article (peer-reviewed)abstract
- Background: recurrent fallers are at especially high risk for injuries. Objective: to study whether tests of physical performance are associated with recurrent falls. Subjects: a total of 10,998 men aged 65 years or above. Methods: questionnaires evaluated falls sustained 12 months preceding testing of grip strength, timed stand, 6-m walk and 20-cm narrow walk test. Means with 95% confidence interval (95% CI) are reported. P < 0.01 is a statistically significant difference. Results: in comparison to both occasional fallers and non-fallers, recurrent fallers performed more poorly on all the physical ability tests (all P < 0.001). A score below -2 standard deviations (SDs) in the right-hand grip strength test was associated with an odds ratio of 2.4 (95% CI 1.7, 3.4) for having had recurrent falls compared with having had no fall and of 2.0 (95% CI 1.3, 3.4) for having had recurrent falls compared with having had an occasional fall. Conclusion: low performance in physical ability tests are in elderly men associated with recurrent falls.
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| 27. |
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| 28. |
- Kwok, T, et al.
(author)
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ACE inhibitor use was associated with lower serum dehydroepiandrosterone concentrations in older men.
- 2010
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In: Clinica chimica acta. - : Elsevier BV. - 1873-3492 .- 0009-8981. ; 411:15-16, s. 1122-5
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Journal article (peer-reviewed)abstract
- CONTEXT: Angiotensin converting enzyme (ACE) activity may influence the production of adrenal androgen precursors and testosterone. Use of ACE inhibitors may therefore have an influence on serum sex hormone concentrations in older men. DESIGN AND METHODS: 1486 out of 2,000 community-dwelling Chinese men aged 65years who participated in a cohort study were randomly selected to have archived fasting morning serum analyzed for androgen precursors and sex hormones. DNA was extracted from whole blood and analyzed for ACE gene I/D polymorphism. RESULTS: Subjects with the ACE gene D allele (higher ACE activity) had higher serum dehydroepiandrosterone (DHEA) sulphate and DHEA than those with I/I genotype (P=0.014 and 0.018 respectively, Mann Whitney test). These differences were not significant after Bonferroni correction. Among those with history of hypertension, but without diabetes mellitus or cardiac failure, users of ACE inhibitors had significantly lower serum DHEA (median 1.78 versus 1.49ng/ml in non-users, P=0.0074, Mann Whitney test) and also tended to have lower serum androstenedione and androst-5-ene-3beta,17beta-diol (0.68 versus 0.72ng/ml in non-users; 552.4 versus 624.1pg/ml respectively, both P values <0.05). Serum testosterone and estradiol were not significantly changed. CONCLUSIONS: ACE inhibitor use was associated with lower serum DHEA in older men.
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| 29. |
- McCloskey, Eugene V, et al.
(author)
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A meta-analysis of trabecular bone score in fracture risk prediction and its relationship to FRAX
- 2016
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In: Journal of Bone and Mineral Research. - : Wiley. - 0884-0431 .- 1523-4681. ; 31:5, s. 940-948
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Journal article (peer-reviewed)abstract
- Trabecular bone score (TBS) is a grey-level textural index of bone microarchitecture derived from lumbar spine dual-energy X-ray absorptiometry (DXA) images. TBS is a BMD-independent predictor of fracture risk. The objective of this meta-analysis was to determine whether TBS predicted fracture risk independently of FRAX probability and to examine their combined performance by adjusting the FRAX probability for TBS. We utilized individual level data from 17,809 men and women in 14 prospective population-based cohorts. Baseline evaluation included TBS and the FRAX risk variables and outcomes during follow up (mean 6.7 years) comprised major osteoporotic fractures. The association between TBS, FRAX probabilities and the risk of fracture was examined using an extension of the Poisson regression model in each cohort and for each sex and expressed as the gradient of risk (GR; hazard ratio per 1SD change in risk variable in direction of increased risk). FRAX probabilities were adjusted for TBS using an adjustment factor derived from an independent cohort (the Manitoba Bone Density Cohort). Overall, the GR of TBS for major osteoporotic fracture was 1.44 (95% CI: 1.35-1.53) when adjusted for age and time since baseline and was similar in men and women (p > 0.10). When additionally adjusted for FRAX 10-year probability of major osteoporotic fracture, TBS remained a significant, independent predictor for fracture (GR 1.32, 95%CI: 1.24-1.41). The adjustment of FRAX probability for TBS resulted in a small increase in the GR (1.76, 95%CI: 1.65, 1.87 vs. 1.70, 95%CI: 1.60-1.81). A smaller change in GR for hip fracture was observed (FRAX hip fracture probability GR 2.25 vs. 2.22). TBS is a significant predictor of fracture risk independently of FRAX. The findings support the use of TBS as a potential adjustment for FRAX probability, though the impact of the adjustment remains to be determined in the context of clinical assessment guidelines.
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| 30. |
- Ong, Kwok Leung, et al.
(author)
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Association of omega 3 polyunsaturated fatty acids with incident chronic kidney disease : pooled analysis of 19 cohorts
- 2023
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In: BMJ. British Medical Journal. - : BMJ Publishing Group Ltd. - 0959-8146 .- 0959-535X. ; 380
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Journal article (peer-reviewed)abstract
- OBJECTIVE: To assess the prospective associations of circulating levels of omega 3 polyunsaturated fatty acid (n-3 PUFA) biomarkers (including plant derived a linolenic acid and seafood derived eicosapentaenoic acid, docosapentaenoic acid, and docosahexaenoic acid) with incident chronic kidney disease (CKD).DESIGN: Pooled analysis.DATA SOURCES: A consortium of 19 studies from 12 countries identified up to May 2020.STUDY SELECTION: Prospective studies with measured n-3 PUFA biomarker data and incident CKD based on estimated glomerular filtration rate.DATA EXTRACTION AND SYNTHESIS: Each participating cohort conducted de novo analysis with prespecified and consistent exposures, outcomes, covariates, and models. The results were pooled across cohorts using inverse variance weighted meta-analysis.MAIN OUTCOME MEASURES: Primary outcome of incident CKD was defined as new onset estimated glomerular filtration rate <60 mL/ min/1.73 m(2). In a sensitivity analysis, incident CKD was defined as new onset estimated glomerular filtration rate <60 mL/min/1.73 m(2) and <75% of baseline rate.RESULTS: 25 570 participants were included in the primary outcome analysis and 4944 (19.3%) developed incident CKD during follow-up (weighted median 11.3 years). In multivariable adjusted models, higher levels of total seafood n-3 PUFAs were associated with a lower incident CKD risk (relative risk per interquintile range 0.92, 95% confidence interval 0.86 to 0.98; P=0.009, I-2=9.9%). In categorical analyses, participants with total seafood n-3 PUFA level in the highest fifth had 13% lower risk of incident CKD compared with those in the lowest fifth (0.87, 0.80 to 0.96; P=0.005, I-2=0.0%). Plant derived a linolenic acid levels were not associated with incident CKD (1.00, 0.94 to 1.06; P=0.94, I-2=5.8%). Similar results were obtained in the sensitivity analysis. The association appeared consistent across subgroups by age (=60 v <60 years), estimated glomerular filtration rate (60-89 v =90 mL/min/1.73 m(2)), hypertension, diabetes, and coronary heart disease at baseline.CONCLUSIONS: Higher seafood derived n-3 PUFA levels were associated with lower risk of incident CKD, although this association was not found for plant derived n-3 PUFAs. These results support a favourable role for seafood derived n-3 PUFAs in preventing CKD.
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| 31. |
- Ong, Kwok Leung, et al.
(author)
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Usefulness of Certain Protein Biomarkers for Prediction of Coronary Heart Disease
- 2020
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In: American Journal of Cardiology. - : EXCERPTA MEDICA INC-ELSEVIER SCIENCE INC. - 0002-9149 .- 1879-1913. ; 125:4, s. 542-548
-
Journal article (peer-reviewed)abstract
- Identification of biomarkers can help monitor and prevent cardiovascular disease (CVD) risk. We performed an exploratory analysis to identify potential biomarkers for coronary heart disease (CHD) in participants from the Life Conditions, Stress, and Health study. A total of 1,007 participants (50% women), randomly selected from the general population, were followed for incident CHD at 8 and 13 years of follow-up. Plasma levels of 184 CVD-related biomarkers were measured in samples collected at baseline in 86 cases with CHD and 184 age- and sex-matched controls by proximity extension assay. Biomarker levels were presented as normalized protein expression values (log 2 scale). After adjusting for confounding factors, 6 biomarkers showed significant association with incident CHD at 13 years. In a sensitivity analysis, this association remained significant at 8 years for 3 biomarkers; collagen alpha-1(I) chain (COL1A1), bone morphogenetic protein-6 (BMP-6), and interleukin-6 receptor alpha chain (IL-6R alpha). When entering these biomarkers in the full adjustment model simultaneously, their association with incident CHD at 13 years remained significant, hazards ratio being 0.671, 0.335, and 2.854, respectively per unit increase in normalized protein expression values. Subjects with low COL1A1, low BMP-6, and high IL-6R alpha levels had a hazards ratio of 5.097 for incident CHD risk (p = 0.019), compared with those without. In conclusion, we identified COL1A1, BMP-6 and IL-6Ra as biomarkers for incident CHD over a long-term follow-up in this exploratory analysis. For COL1A1 and BMP-6 this has not been previously reported. Further studies are needed to confirm our findings and establish their clinical relevance. (C) 2019 Elsevier Inc. All rights reserved.
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| 32. |
- Qian, Frank, et al.
(author)
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Omega-3 Fatty Acid Biomarkers and Incident Atrial Fibrillation
- 2023
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In: Journal of the American College of Cardiology. - : Elsevier. - 0735-1097 .- 1558-3597. ; 82:4, s. 336-349
-
Journal article (peer-reviewed)abstract
- BACKGROUND: The relationship between omega-3 fatty acids and atrial fibrillation (AF) remains controversial.OBJECTIVES: This study aimed to determine the prospective associations of blood or adipose tissue levels of eicosa-pentaenoic acid (EPA), docosapentaenoic acid (DPA), and docosahexaenoic acid (DHA) with incident AF.METHODS: We used participant-level data from a global consortium of 17 prospective cohort studies, each with baseline data on blood or adipose tissue omega-3 fatty acid levels and AF outcomes. Each participating study conducted a de novo analyses using a prespecified analytical plan with harmonized definitions for exposures, outcome, covariates, and sub-groups. Associations were pooled using inverse-variance weighted meta-analysis.RESULTS: Among 54,799 participants from 17 cohorts, 7,720 incident cases of AF were ascertained after a median 13.3 years of follow-up. In multivariable analysis, EPA levels were not associated with incident AF, HR per interquintile range (ie, the difference between the 90th and 10th percentiles) was 1.00 (95% CI: 0.95-1.05). HRs for higher levels of DPA, DHA, and EPA+DHA, were 0.89 (95% CI: 0.83-0.95), 0.90 (95% CI: 0.85-0.96), and 0.93 (95% CI: 0.87-0.99), respectively.CONCLUSIONS: In vivo levels of omega-3 fatty acids including EPA, DPA, DHA, and EPA+DHA were not associated with increased risk of incident AF. Our data suggest the safety of habitual dietary intakes of omega-3 fatty acids with respect to AF risk. Coupled with the known benefits of these fatty acids in the prevention of adverse coronary events, our study suggests that current dietary guidelines recommending fish/omega-3 fatty acid consumption can be maintained.
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| 33. |
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| 34. |
- Rosengren, Björn, et al.
(author)
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Inferior physical performance test results of 10,998 men in the MrOS Study is associated with high fracture risk.
- 2012
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In: Age and ageing. - : Oxford University Press (OUP). - 1468-2834 .- 0002-0729. ; 41:3, s. 339-44
-
Journal article (peer-reviewed)abstract
- Background: most fractures are preceded by falls. Objective: the aim of this study was to determine whether tests of physical performance are associated with fractures. Subjects: a total of 10,998 men aged 65 years or above were recruited. Methods: questionnaires evaluated falls sustained 12 months before administration of the grip strength test, the timed stand test, the six-metre walk test and the twenty-centimetre narrow walk test. Means with 95% confidence interval (95% CI) are reported. P < 0.05 is a statistically significant difference. Results: fallers with a fracture performed worse than non-fallers on all tests (all P < 0.001). Fallers with a fracture performed worse than fallers with no fractures both on the right-hand-grip strength test and on the six-metre walk test (P < 0.001). A score below –2 standard deviations in the right-hand-grip strength test was associated with an odds ratio of 3.9 (95% CI: 2.1–7.4) for having had a fall with a fracture compared with having had no fall and with an odds ratio of 2.6 (95% CI: 1.3–5.2) for having had a fall with a fracture compared with having had a fall with no fracture. Conclusion: the right-hand-grip strength test and the six-metre walk test performed by old men help discriminate fallers with a fracture from both fallers with no fracture and non-fallers.
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| 35. |
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| 36. |
- Smith, Peter B., et al.
(author)
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Demographic Effects on the Use of Vertical Sources of Guidance by Managers in Widely Differing Cultural Contexts
- 2005
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In: International Journal of Cross Cultural Management. - : Sage Publications. - 1470-5958 .- 1741-2838. ; 5:1, s. 5-26
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Journal article (peer-reviewed)abstract
- Data provided by 7380 middle managers from 60 nations are used to determine whether demographic variables are correlated with managers’ reliance on vertical sources of guidance in different nations and whether these correlations differ depending on national culture characteristics. Significant effects of Hofstede’s national culture scores, age, gender, organization ownership and department function are found. After these main effects have been discounted, significant although weak interactions are found, indicating that demographic effects are stronger in individualist, low power distance nations than elsewhere. Significant non-predicted interaction effects of uncertainty avoidance and masculinity-femininity are also obtained. The implications for theory and practice of the use of demographic attributes in understanding effective management procedures in various parts of the world are discussed.
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| 37. |
- Song, Xin-Yuan, et al.
(author)
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A semiparametric Bayesian approach for structural equation models.
- 2010
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In: Biometrical journal.. - : Wiley. - 1521-4036 .- 0323-3847. ; 52:3, s. 314-32
-
Journal article (peer-reviewed)abstract
- In the development of structural equation models (SEMs), observed variables are usually assumed to be normally distributed. However, this assumption is likely to be violated in many practical researches. As the non-normality of observed variables in an SEM can be obtained from either non-normal latent variables or non-normal residuals or both, semiparametric modeling with unknown distribution of latent variables or unknown distribution of residuals is needed. In this article, we find that an SEM becomes nonidentifiable when both the latent variable distribution and the residual distribution are unknown. Hence, it is impossible to estimate reliably both the latent variable distribution and the residual distribution without parametric assumptions on one or the other. We also find that the residuals in the measurement equation are more sensitive to the normality assumption than the latent variables, and the negative impact on the estimation of parameters and distributions due to the non-normality of residuals is more serious. Therefore, when there is no prior knowledge about parametric distributions for either the latent variables or the residuals, we recommend making parametric assumption on latent variables, and modeling residuals nonparametrically. We propose a semiparametric Bayesian approach using the truncated Dirichlet process with a stick breaking prior to tackle the non-normality of residuals in the measurement equation. Simulation studies and a real data analysis demonstrate our findings, and reveal the empirical performance of the proposed methodology. A free WinBUGS code to perform the analysis is available in Supporting Information.
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| 38. |
- Vandenput, Liesbeth, 1974, et al.
(author)
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High Serum SHBG Predicts Incident Vertebral Fractures in Elderly Men.
- 2016
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In: Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research. - : Wiley. - 1523-4681 .- 0884-0431. ; 31:3, s. 683-689
-
Journal article (peer-reviewed)abstract
- Previous prospective cohort studies have shown that serum levels of sex steroids and sex hormone-binding globulin (SHBG) associate with non-vertebral fracture risk in men. The predictive value of sex hormones and SHBG for vertebral fracture risk specifically is, however, less studied. Elderly men (aged ≥65 years) from Sweden and Hong Kong participating in the MrOS study had baseline estradiol and testosterone analyzed by GC-MS and SHBG by IRMA. Incident clinical vertebral fractures (n=242 cases) were evaluated in 4324 men during an average follow-up of 9.1 years. In a subsample of these men (n=2256), spine X-rays were obtained at baseline and after an average follow-up of 4.3 years to identify incident radiographic vertebral fractures (n=157 cases). The likelihood of incident clinical and radiographic vertebral fractures was estimated by Cox proportional hazards models and logistic regression models, respectively. Neither serum estradiol (HR per SD increase, 95% CI: 0.93, 0.80-1.08) nor testosterone (1.05, 0.91-1.21) predicted incident clinical vertebral fractures in age-adjusted models in the combined data set. High serum SHBG, however, associated with increased clinical vertebral fracture risk (1.24, 1.12-1.37). This association remained significant after further adjustment for FRAX® with or without BMD. SHBG also associated with increased incident radiographic vertebral fracture risk (combined data set; OR per SD increase, 95% CI: 1.23, 1.05-1.44). This association remained significant after adjustment for FRAX® with or without BMD. In conclusion, high SHBG predicts incident clinical and radiographic vertebral fractures in elderly men and adds moderate information beyond FRAX® with BMD for vertebral fracture risk prediction. This article is protected by copyright. All rights reserved.
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| 39. |
- Vandenput, Liesbeth, 1974, et al.
(author)
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Low Testosterone, but Not Estradiol, Is Associated With Incident Falls in Older Men: The International MrOS Study
- 2017
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In: Journal of Bone and Mineral Research. - : Wiley. - 0884-0431 .- 1523-4681. ; 32:6, s. 1174-1181
-
Journal article (peer-reviewed)abstract
- Fracture risk is determined by bone strength and the risk of falls. The relationship between serum sex steroids and bone strength parameters in men is well known, whereas the predictive value of sex steroids for falls is less studied. The aim of this study was to assess the associations between serum testosterone (T) and estradiol (E2) and the likelihood of falls. Older men (aged > 65 years) from the United States (n = 1919), Sweden (n = 2495), and Hong Kong (n = 1469) participating in the Osteoporotic Fractures in Men Study had baseline T and E2 analyzed by mass spectrometry. Bioavailable (Bio) levels were calculated using mass action equations. Incident falls were ascertained every 4 months during a mean follow-up of 5.7 years. Associations between sex steroids and falls were estimated by generalized estimating equations. Fall rate was highest in the US and lowest in Hong Kong (US 0.50, Sweden 0.31, Hong Kong 0.12 fall reports/person/year). In the combined cohort of 5883 men, total T (odds ratio [OR] per SD increase = 0.88, 95% confidence interval [CI] 0.86-0.91) and BioT (OR = 0.86, 95% CI 0.83-0.88) were associated with incident falls in models adjusted for age and prevalent falls. These associations were only slightly attenuated after simultaneous adjustment for physical performance variables (total T: OR = 0.94, 95% CI 0.91-0.96; BioT: OR = 0.91, 95% CI 0.89-0.94). E2, BioE2, and sex hormone-binding globulin (SHBG) were not significantly associated with falls. Analyses in the individual cohorts showed that both total T and BioT were associated with falls in MrOS US and Sweden. No association was found in MrOS Hong Kong, and this may be attributable to environmental factors rather than ethnic differences because total T and BioT predicted falls in MrOS US Asians. In conclusion, low total T and BioT levels, but not E2 or SHBG, are associated with increased falls in older men. (C) 2017 American Society for Bone and Mineral Research.
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| 40. |
- Zhu, Timothy C., et al.
(author)
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Report of AAPM Therapy Physics Committee Task Group 74 : In-air output ratio, Sc, for megavoltage photon beams
- 2009
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In: Medical physics (Lancaster). - : Wiley. - 0094-2405. ; 36:11, s. 5261-5291
-
Research review (peer-reviewed)abstract
- The concept of in-air output ratio (Sc) was introduced to characterize how the incident photon fluence per monitor unit (or unit time for a Co-60 unit) varies with collimator settings. However, there has been much confusion regarding the measurement technique to be used that has prevented the accurate and consistent determination of Sc. The main thrust of the report is to devise a theoretical and measurement formalism that ensures interinstitutional consistency of Sc. The in-air output ratio, Sc, is defined as the ratio of primary collision water kerma in free-space, Kp, per monitor unit between an arbitrary collimator setting and the reference collimator setting at the same location. Miniphantoms with sufficient lateral and longitudinal thicknesses to eliminate electron contamination and maintain transient electron equilibrium are recommended for the measurement of Sc. The authors present a correction formalism to extrapolate the correct Sc from the measured values using high-Z miniphantom. Miniphantoms made of high-Z material are used to measure Sc for small fields (e.g., IMRT or stereotactic radiosurgery). This report presents a review of the components of Sc, including headscatter, source-obscuring, and monitor-backscattering effects. A review of calculation methods (Monte Carlo and empirical) used to calculate Sc for arbitrary shaped fields is presented. The authors discussed the use of Sc in photon dose calculation algorithms, in particular, monitor unit calculation. Finally, a summary of Sc data (from RPC and other institutions) is included for QA purposes.
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