| 41. |
- Fries, Johan, et al.
(författare)
-
Key parameters for droplet evaporation and mixing at the cloud edge
- 2021
-
Ingår i: Quarterly Journal of the Royal Meteorological Society. - : Wiley. - 0035-9009 .- 1477-870X. ; 147:737, s. 2160-2172
-
Tidskriftsartikel (refereegranskat)abstract
- The distribution of liquid water in ice-free clouds determines their radiative properties, a significant source of uncertainty in weather and climate models. Evaporation and turbulent mixing cause a cloud to display large variations in droplet number density, but quite small variations in droplet size (Beals et al., Science, 2015, vol. 350, pp. 87-90). However, direct numerical simulations of the joint effect of evaporation and mixing near the cloud edge predict quite different behaviours, and how to reconcile these results with the experimental findings remains an open question. To infer the history of mixing and evaporation from observational snapshots of droplets in clouds is challenging, because clouds are transient systems. We formulated a statistical model that provides a reliable description of the evaporation-mixing process as seen in direct numerical simulations and allows us to infer important aspects of the history of observed droplet populations, highlighting the key mechanisms at work and explaining the differences between observations and simulations.
|
|
| 42. |
- Fries, Johan, et al.
(författare)
-
Lagrangian Supersaturation Fluctuations at the Cloud Edge
- 2023
-
Ingår i: Physical Review Letters. - : American Physical Society (APS). - 1079-7114 .- 0031-9007. ; 131:25
-
Tidskriftsartikel (refereegranskat)abstract
- Evaporation of cloud droplets accelerates when turbulence mixes dry air into the cloud, affecting droplet-size distributions in atmospheric clouds, combustion sprays, and jets of exhaled droplets. The challenge is to model local correlations between droplet numbers, sizes, and supersaturation, which determine supersaturation fluctuations along droplet paths (Lagrangian fluctuations). We derived a statistical model that accounts for these correlations. Its predictions are in quantitative agreement with results of direct numerical simulations, and explain the key mechanisms at play.
|
|
| 43. |
- Funkquist, Anders, 1977-, et al.
(författare)
-
Higher CSF/serum free-T4 ratio is associated with improvement of quality of life during treatment with L-thyroxine
- 2023
-
Ingår i: Journal of Neuroendocrinology. - : Wiley-Blackwell Publishing Inc.. - 0953-8194 .- 1365-2826. ; 35:5
-
Tidskriftsartikel (refereegranskat)abstract
- Up to 20% of individuals with primary hypothyroidism treated with L-thyroxine still suffer from severe symptoms. These are supposedly brain derived and involve both cognitive and emotional domains. Previously, no consistent relationship has been found between thyroid hormones (TH) or TSH levels in blood and quality of life (QoL). Recently, we reported an association between cerebrospinal fluid (CSF)/serum free-thyroxine (f-T4) ratio and QoL, in juvenile hypothyroid patients. Here, we investigated if CSF/serum f-T4 ratio and QoL estimates correlate also during L-thyroxine treatment. Moreover, the CSF biomarker neurogranin (Ng) was used as a biomarker for synaptic function and integrity in clinical research. Ng is partially controlled by TH and therefore we investigated the relationship between QoL parameters and Ng levels. Patients diagnosed with primary hypothyroidism were investigated using vital parameters, serum and CSF analyses of TH, TSH, Ng and QoL questionnaires. Similar procedures were performed after 6 months of treatment. The most marked associations with QoL were found for CSF/serum f-T4 ratio, which was strongly related to several QoL parameters such as the mental subscore of SF-36 (r = 0.83, p < .0005). Ng, which did not differ from that in our healthy controls, was lower in some patients during treatment and higher in others. However, the change in Ng during treatment was significantly correlated with QoL parameters including the mental subscore of SF-36 (r = -0.86, p < .0001). In addition, the CSF/serum f-T4 ratio correlated with the change in Ng (r = -0.75, p = .001). Our results suggest that the ratio between CSF and serum f-T4 is an important biomarker for QoL during treatment of patients with primary hypothyroidism, so far in research, but in the future maybe also in clinical settings. Moreover, this ratio also correlates with the changes in Ng levels during L-thyroxine treatment, further supporting the impact of the TH balance between serum and CSF on QoL.
|
|
| 44. |
- Götherström, Galina, 1962, et al.
(författare)
-
A 10-year, prospective study of the metabolic effects of growth hormone replacement in adults.
- 2007
-
Ingår i: The Journal of clinical endocrinology and metabolism. - : The Endocrine Society. - 0021-972X .- 1945-7197. ; 92:4, s. 1442-5
-
Tidskriftsartikel (refereegranskat)abstract
- CONTEXT: Only a few studies have investigated the effects of GH replacement in adults for more than 5 yr. OBJECTIVE/DESIGN/PATIENTS: In a prospective, open-label, single-center study, the effects of 10-yr GH replacement were determined. Eighty-seven consecutive patients (52 men and 35 women), with a mean age of 44.1 (range 22-74) yr with adult-onset GH deficiency (GHD) were included. RESULTS: The initial mean dose of GH (0.98 mg/d) was reduced during the study and at yr 10 was 0.47 mg/d. The mean IGF-I sd score increased from -1.81 at baseline to 1.29 at study end. The absolute reduction in total body fat was transient. However, after correction for age and sex using a four-compartment model, the reduction in body fat was sustained during the 10-yr study period. There was a sustained improvement in serum lipid profile and after 10 yr, and blood glycosylated hemoglobin level was reduced. The treatment responses in IGF-I sd score, serum high-density lipoprotein cholesterol level, and body composition as measured using dual-energy x-ray absorptiometry were more marked in men, whereas women had a more marked reduction in blood glycosylated hemoglobin level. CONCLUSION: The effect on the absolute amount of body fat was seen early and was transient, which could be due to the normal aging of the patients. The effects on metabolic indices were detected later, but they were sustained and even progressive throughout the study period.
|
|
| 45. |
- Götherström, Galina, 1962, et al.
(författare)
-
Effects of 18 months of GH replacement on cardiovascular risk factors and quality of life in GH deficient adults; a randomized controlled trial using a fixed very low and a standard dose of GH
- 2022
-
Ingår i: Growth Hormone & Igf Research. - : Elsevier BV. - 1096-6374. ; 67
-
Tidskriftsartikel (refereegranskat)abstract
- Objective: Little is known of the effects of a fixed very low dose of growth hormone (GH) replacement on car-diovascular risk factors, bone mass, muscle strength and quality of life (QoL) in hypopituitary patients.Design/patients/methods: This was an open-label randomized study performed at a single center. Consecutive hypopituitary patients with adult onset GH deficiency (GHD) and BMI >= 27 kg/m2 were randomized to receive a very low fixed dose of GH (LG, n = 9) or a standard dose of GH (SG, n = 9). Body composition, glucose and lipid metabolism, bone mineral content (BMC) and density (BMD), muscle strength, and QoL were measured at baseline and after 6, 12 and 18 months. Results: The fixed GH dose in LG was 0.1 mg/day. In SG, the mean baseline GH dose of 0.13 mg/day was gradually increased to 0.31 mg/day at study end. Lean body mass (LBM) as measured using DEXA as well as total body water (TBW) and extracellular water (ECW) were increased only in SG (P < 0.01, P < 0.05, and P < 0.01 vs. LG, respectively). There were no between-groups differences in BMD, BMC, insulin sensitivity, lipids, or muscle strength. Finally, although not significant compared with SG, a sustained improvement in QoL was seen in LG according to the QoL-AGHDA questionnaire. Conclusion: In this pilot study, a fixed very low GH dose improved QoL in GHD adults without any induction of fluid retention. Other effects were comparable to those produced by the standard GH dose. Replacement with a very low GH dose could therefore be a treatment option in hypopituitary patients, especially in patients who do not tolerate higher GH dosage.Trial registrationThis study is registered at ClinicalTrials.gov, EU-nr 2009-016783-37.
|
|
| 46. |
- Götherström, Galina, 1962, et al.
(författare)
-
Muscle strength in elderly adults with GH deficiency after 10 years of GH replacement.
- 2010
-
Ingår i: European journal of endocrinology / European Federation of Endocrine Societies. - 1479-683X. ; 163:2, s. 207-15
-
Tidskriftsartikel (refereegranskat)abstract
- CONTEXT: Only few studies have investigated the effects of GH replacement on muscle strength in elderly patients with GH deficiency (GHD). OBJECTIVE, DESIGN, AND PATIENTS: In this prospective open-labeled study, the effects of 10 years of GH replacement on muscle strength and neuromuscular function were followed in 24 elderly GHD adults (mean age of 65.2 years; range 61-74 years). Muscle strength was compared with reference values obtained from the background population. RESULTS: The mean initial GH dose of 0.72 mg/day was lowered to 0.37 mg/day. The mean IGF1 SDS increased from -1.10 at baseline to 1.17 at study end. GH replacement induced a sustained increase in lean body mass and a transient increase in isometric knee flexor strength. Isometric knee extensor strength was reduced after 10 years. However, after correction for age and gender, using observed/predicted value ratios, there was sustained and even progressive increase in most variables reflecting muscle strength. Measurements of neuromuscular function showed unchanged voluntary motor unit activation after 10 years. CONCLUSIONS: Ten years of GH replacement therapy in elderly GHD adults resulted in a transient increase in isometric knee flexor strength, and provided protection from most of the normal age-related decline in muscle performance and neuromuscular function.
|
|
| 47. |
- Götherström, Galina, 1962, et al.
(författare)
-
Ten-year GH replacement increases bone mineral density in hypopituitary patients with adult onset GH deficiency.
- 2007
-
Ingår i: European journal of endocrinology / European Federation of Endocrine Societies. - : Oxford University Press (OUP). - 0804-4643. ; 156:1, s. 55-64
-
Tidskriftsartikel (refereegranskat)abstract
- There are few studies that have determined the effects of long-term GH replacement on bone mineral density (BMD) in GH-deficient (GHD) adults. In this study, the effects of 10 years of GH replacement on BMD were assessed in 87 GHD adults using dual energy X-ray absorptiometry (DEXA). The results show that GH replacement induced a sustained increase in BMD at all the skeletal sites measured. INTRODUCTION: Little is known of the effect of more than 5 years of GH replacement therapy on bone metabolism in GHD adults. PATIENTS AND METHODS: In this prospective, open-label, single-center study, which included 87 consecutive adults (52 men and 35 women; mean age of 44.1 (range 22-74) years) with adulthood onset GHD, the effect of 10 years of GH replacement on BMD was determined. RESULTS: The mean initial dose of GH was 0.98 mg/day. The dose was gradually lowered and after 10 years the mean dose was 0.47 mg/day. The mean insulin-like growth factor-I (IGF-I) SDS increased from 1.81 at baseline to 1.29 at study end. The GH replacement induced a sustained increase in total, lumbar (L2-L4) and femur neck BMD, and bone mineral content (BMC) as measured by DEXA. The treatment response in IGF-I SDS was more marked in men, whereas women had a more marked increase in the total body BMC and the total body z-score. There was a tendency for women on estrogen treatment to have a larger increase in bone mass and density compared with women without estrogen replacement. CONCLUSIONS: Ten years of GH replacement in hypopituitary adults induced a sustained, and in some variables even a progressive, increase in bone mass and bone density. The study results also suggest that adequate estrogen replacement is needed in order to have an optimal response in BMD in GHD women.
|
|
| 48. |
- Götherström, Galina, 1962, et al.
(författare)
-
Ten years of growth hormone (GH) replacement normalizes muscle strength in GH-deficient adults.
- 2009
-
Ingår i: The Journal of clinical endocrinology and metabolism. - : The Endocrine Society. - 1945-7197 .- 0021-972X. ; 94:3, s. 809-16
-
Tidskriftsartikel (refereegranskat)abstract
- CONTEXT: GH replacement for 1-5 yr improves, but does not fully normalize, muscle strength. OBJECTIVE, DESIGN, AND PATIENTS: In this single-center, open-labeled, prospective study, the effects of 10 yr of GH replacement on muscle strength and neuromuscular function were followed in 109 consecutive adults (61 men; mean age 50.0 yr; range 22-74 yr) with adult-onset GH deficiency. RESULTS: The mean initial GH dose of 0.88 mg/d was gradually lowered to 0.47 mg/d. The mean IGF-I sd score increased from -1.54 at baseline to 1.12 at study end. GH replacement induced a sustained increase in lean mass and isometric knee flexor strength (60 degrees). In most other measures of upper leg and handgrip strength, there were transient increases during the first half of the study (0-5 yr), whereas during the second half (5-10 yr), the absolute values of muscle strength decreased and returned to or even below the baseline values. However, after correction for age and gender using observed/predicted value ratios, there were sustained and, until 7 yr, even progressive increases in the measures of muscle strength. At study end, knee flexor strength had increased to 104-110% of predicted, knee extensor strength to 93-108%, and handgrip strength to 88-93%. Measurements of neuromuscular function showed reduced voluntary motor unit activation after 10 yr. CONCLUSIONS: Ten years of GH replacement therapy increased muscle strength during the first half of the study and thereafter partly protected against the normal age-related decline in muscle strength and neuromuscular function, resulting in approximately normalized muscle strength after 10 yr.
|
|
| 49. |
- Götherström, Galina, 1962, et al.
(författare)
-
The effects of five-year growth hormone replacement therapy on muscle strength in elderly hypopituitary patients.
- 2005
-
Ingår i: Clinical endocrinology. - : Wiley. - 0300-0664 .- 1365-2265. ; 62:1, s. 105-13
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Little is known of the long-term effects of GH replacement therapy on muscle strength in elderly adults with adult onset GH deficiency (GHD). In this study, the effects of 5 years of GH replacement therapy on muscle function were determined in adults over 60 years of age with adult onset GHD. DESIGN: A prospective, open-label, single-centre study. Patients Twenty-six (12 male and 14 female) consecutive hypopituitary adults with adult onset GHD, mean age 65.0 (range 61-74) years. MEASUREMENTS: Upper leg muscle strength was measured using a Kin-Com dynamometer. Right and left handgrip strength were measured using an electronic grip force instrument. RESULTS: The mean insulin-like growth factor-I (IGF-I) SD score increased from -1.10 at baseline to 1.21 at end of the study. Body weight was unchanged during the 5-year study. A sustained increase in lean body mass and a sustained reduction of body fat was observed as measured using dual-energy X-ray absorptiometry (DEXA). The GH replacement therapy induced a sustained increase in isometric (60 degrees ) knee flexor strength. After statistical correction for age and sex variables using observed/predicted value ratios, a sustained increase was also observed in concentric knee flexor strength at an angular velocity of 60 degrees /s, concentric knee extensor strength at 60 degrees /s and 180 degrees /s, and peak right handgrip strength. At baseline, knee flexor strength was 90-96% of predicted, knee extensor strength was 85-87% of predicted, and hand-grip strength was 74-80% of predicted values. At study end, knee flexor strength was 98-106% of predicted, knee extensor strength was 90-100% of predicted, and hand-grip strength was 80-87% of predicted values. CONCLUSION: Elderly patients with adult onset GH deficiency had decreased baseline muscle strength also after correction for age and sex. The 5-year GH replacement therapy normalized knee flexor strength and improved, but did not fully normalize, knee extensor strength and handgrip strength.
|
|
| 50. |
|
|
