| 1. |
- Beal, Jacob, et al.
(författare)
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Robust estimation of bacterial cell count from optical density
- 2020
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Ingår i: Communications Biology. - : Springer Science and Business Media LLC. - 2399-3642. ; 3:1
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Tidskriftsartikel (refereegranskat)abstract
- Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data.
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| 2. |
- Gao, Menghan, et al.
(författare)
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Associations of perinatal characteristics with endometriosis : a nationwide birth cohort study
- 2020
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Ingår i: International Journal of Epidemiology. - : Oxford University Press (OUP). - 1464-3685 .- 0300-5771. ; 49:2, s. 537-547
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Perinatal characteristics are associated with subsequent risk of several chronic diseases. Previous studies regarding endometriosis were based on small samples and retrospective data and were limited by unmeasured confounding bias, leading to conflicting and inconclusive findings. We investigated the associations of maternal and birth characteristics with risk of endometriosis among Swedish women of reproductive age. METHODS: This total-population register-based cohort study consisted of 628 312 singleton women born in Sweden between 1973 and 1987, who were followed for diagnosed endometriosis from age 15 years until the end of 2012. Multivariable Cox regression was applied to examine associations with perinatal characteristics. Residual unmeasured confounding was assessed through within-family and E-value analyses. RESULTS: During follow-up, 8262 women received an endometriosis diagnosis. There were clear dose-response/linear associations of endometriosis with lower maternal education, endometriosis in the mother [adjusted hazard ratio (aHR): 2.24, 95% confidence interval (CI): 2.04-2.46], maternal smoking during pregnancy (aHR: 1.18, 95% CI: 1.04-1.33 for moderate smoker and aHR: 1.36, 95% CI: 1.18-1.57 for heavy smoker vs non-smoker), lower birthweight, and lower birthweight-for-gestational age (aHR: 0.93 per standard deviation increase, 95% CI: 0.91-0.95). Within-family and E-value analyses suggested that these perinatal characteristics are robust predictors of the incidence of endometriosis. We also found that an estimated 26% of the association between maternal smoking and early-onset endometriosis could be explained by birthweight-for-gestational age. CONCLUSION: This study finds support for fetal origins of endometriosis, in that exposure to adverse environment or restricted development during the perinatal period may increase the risk. Further research is needed to provide an understanding of the underlying mechanisms.
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| 3. |
- Gao, Menghan, et al.
(författare)
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Psychiatric comorbidity among women with endometriosis : nationwide cohort study in Sweden
- 2020
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Ingår i: American Journal of Obstetrics and Gynecology. - : Elsevier BV. - 0002-9378 .- 1097-6868. ; 223:3, s. 415.e1-415.e16
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Tidskriftsartikel (refereegranskat)abstract
- Background Endometriosis is a common gynecologic condition affecting women of reproductive age. It has been linked with greater rates of depression and anxiety in small, cross-sectional, and clinical studies. Other studies have reported that women with endometriosis have increased risk of bipolar disorder. These reports suggest that psychiatric disorders might be more common among women with endometriosis, contributing to increased burden of mental ill-health in this population of women. However, this hypothesis has not been adequately studied.Objectives In this population-based study, we investigated the overall psychiatric comorbidity among women with endometriosis, and the role of familial liability.Study Design Several Swedish national registers were linked and used to follow all women born in Sweden in 1973–1990 for diagnosed psychiatric disorders and endometriosis from age 14 years until year 2016. Sibling comparison analyses were performed in a subsample of 173,650 families.Results After adjustment for birth characteristics and education, women with endometriosis had an increased risk of being later diagnosed with depressive-, anxiety and stress-related disorders, alcohol/drug dependence, and attention-deficit hyperactivity disorder compared with the general population and with their sisters without endometriosis. The adjusted hazard ratios ranged from 1.56 (95% confidence interval, 1.29–1.88) for depressive disorders to 1.98 (95% confidence interval, 1.34–2.93) for attention-deficit hyperactivity disorder in the sibling analysis. Also, women with previous affective psychotic disorders, depressive-, anxiety and stress-related disorders, eating disorders, personality disorders, and attention-deficit hyperactivity disorder were more likely to be later diagnosed with endometriosis. The adjusted hazard ratios ranged from 1.51 (95% confidence interval, 1.30–1.76) for depressive disorders to 1.93 (95% confidence interval, 1.47–2.52) for personality disorders.Conclusion These findings reveal a high degree of comorbidity between endometriosis and many psychiatric disorders that was not entirely explained by shared familial confounding. Clinical practice may consider psychosocial support to women with endometriosis and treating them from a multidisciplinary perspective.
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