| 51. |
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| 52. |
- Carlsson, J, et al.
(författare)
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Time-resolved Studies of Light-propagation In Paper
- 1995
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Ingår i: Applied Optics. - 2155-3165. ; 34:9, s. 1528-1535
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Tidskriftsartikel (refereegranskat)abstract
- A method for time-resolved recording of light scattering in thin, highly scattering media is described. Subpicosecond pulses from a high-power Ti:sapphire laser are used, and single-shot recordings of the scattered light are made with a fast streak camera. The method is applied to the study of light scattering in paper, and a 1-ps resolution is demonstrated. The dependence of the light scattering on the basis of weight and density of the paper has been studied. A white-light continuum generated from the high-power pulses by the use of self phase modulation in water is used to study the wavelength dependence of the scattering process. A model for the propagation of light in paper has been developed and used in Monte Carlo simulations. The experimental results are used for testing this model, and absorption and scattering parameters are determined from that comparison.
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| 53. |
- Carlström, Mattias, 1941-, et al.
(författare)
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Dietary nitrate attenuates oxidative stress, prevents cardiac and renal injuries, and reduces blood pressure in salt-induced hypertension
- 2011
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Ingår i: Cardiovascular Research. - : Oxford University Press (OUP). - 0008-6363 .- 1755-3245. ; 89:3, s. 574-585
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Tidskriftsartikel (refereegranskat)abstract
- Aims Reduced bioavailability of endogenous nitric oxide (NO) is a central pathophysiological event in hypertension and other cardiovascular diseases. Recently, it was demonstrated that inorganic nitrate from dietary sources is converted in vivo to form nitrite, NO, and other bioactive nitrogen oxides. We tested the hypothesis that dietary inorganic nitrate supplementation may have therapeutic effects in a model of renal and cardiovascular disease. Methods and results Sprague-Dawley rats subjected to unilateral nephrectomy and chronic high-salt diet from 3 weeks of age developed hypertension, cardiac hypertrophy and fibrosis, proteinuria, and histological as well as biochemical signs of renal damage and oxidative stress. Simultaneous nitrate treatment (0.1 or 1 mmol nitrate kg(-1) day(-1)), with the lower dose resembling the nitrate content of a diet rich in vegetables, attenuated hypertension dose-dependently with no signs of tolerance. Nitrate treatment almost completely prevented proteinuria and histological signs of renal injury, and the cardiac hypertrophy and fibrosis were attenuated. Mechanistically, dietary nitrate restored the tissue levels of bioactive nitrogen oxides and reduced the levels of oxidative stress markers in plasma (malondialdehyde) and urine (Class VI F2-isoprostanes and 8-hydroxy-2-deoxyguanosine). In addition, the increased circulating and urinary levels of dimethylarginines (ADMA and SDMA) in the hypertensive rats were normalized by nitrate supplementation. Conclusion Dietary inorganic nitrate is strongly protective in this model of renal and cardiovascular disease. Future studies will reveal if nitrate contributes to the well-known cardioprotective effects of a diet rich in vegetables.
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| 54. |
- Carroll, David C., et al.
(författare)
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Dynamic control and enhancement of laser-accelerated protons using multiple laser pulses
- 2009
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Ingår i: Comptes Rendus. Physique. - : Elsevier BV. - 1631-0705. ; 10:2-3, s. 188-196
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Tidskriftsartikel (refereegranskat)abstract
- The use of schemes involving multiple laser pulses to enhance and control the properties of beams of protons accelerated in ultra-intense laser irradiation of planar foil targets is discussed. Specifically, the schemes include the use of a second laser pulse to produce and control preplasma expansion of the target to enhance energy coupling to the proton beam; the use of a second laser pulse to drive shock deformation of the target to change the direction of the proton beam; and a scheme involving dual high intensity laser pulses to change the properties of the sheath field, with the aim of modifying the proton energy spectrum. An overview of our recent experimental and theoretical results is given. The overall aim of this work is to determine the extent to which the properties of the sheath-accelerated proton beam can be optically controlled, to enable beam delivery at high repetition rates. To cite this article: D.C. Carroll et al., C. R. Physique 10 (2009). (C) 2009 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved.
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| 55. |
- Cassou, K., et al.
(författare)
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Optimization toward a high-average-brightness soft-x-ray laser pumped at grazing incidence
- 2007
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Ingår i: Optics Letters. - 0146-9592. ; 32:2, s. 139-141
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Tidskriftsartikel (refereegranskat)abstract
- We report the near-field imaging characterization of a 10 Hz Ni-like 18.9 nm molybdenum soft-x-ray laser pumped in a grazing incidence pumping (GRIP) geometry with a table-top laser driver. We investigate the effect of varying the GRIP angle on the spatial behavior of the soft-x-ray laser source. After multiparameter optimization, we were able to find conditions to generate routinely a high-repetition-rate soft-x-ray laser with an energy level of up to 3 mu J/pulse and to 6 x 10(17) photons/s/mm(2)/mrad(2)/(0.1% bandwidth) average brightness and 1 x 10(28) photons/s/mm(2)/mrad(2)/(0.1% bandwidth) peak brightness. (c) 2006 Optical Society of America.
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| 56. |
- Ceberg, Crister, et al.
(författare)
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A stochastic model for subcellular dosimetry in boron neutron capture therapy
- 1995
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Ingår i: Physics in Medicine and Biology. - : IOP Publishing. - 1361-6560 .- 0031-9155. ; 40:11, s. 1819-1830
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Tidskriftsartikel (refereegranskat)abstract
- The therapeutic effectiveness of boron neutron capture therapy is highly dependent on the microscopic distribution of the administered boron compound. Two boron compounds with different uptake mechanisms in the tumour cells may thus cause effects of different degrees even if the macroscopic boron concentrations in the tumour tissue are the same. This difference is normally expressed quantitatively by the so-called relative local efficiency (RLE). In this work, a stochastic model for the subcellular dosimetry has been developed. This model can be used to calculate the probability for an energy deposition above a certain threshold level in the cell nucleus due to a single neutron capture reaction. If a threshold cell-kill function is assumed, and if the dose is low enough that multiple energy depositions are rare, the model can also be applied to calculations of the survival probability for a cell population. Subcellular boron distributions in rats carrying RG 2 rat gliomas were measured by subcellular fractionation after administration of two different boron compounds: a sulphydryl boron hydride (BSH) and a boronated porphyrin (BOPP). Based on these data, the RLE factors were then calculated for these compounds using the stochastic model.
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| 57. |
- Ceberg, Crister, et al.
(författare)
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Performance of sulfhydryl boron hydride in patients with grade III and IV astrocytoma: a basis for boron neutron capture therapy
- 1995
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Ingår i: Journal of Neurosurgery. - 0022-3085. ; 83:1, s. 79-85
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Tidskriftsartikel (refereegranskat)abstract
- This study investigated the rationale of boron neutron capture therapy (BNCT) for the treatment of Grade III and IV astrocytoma. The European Community joint research program on BNCT plans to use sulfhydryl boron hydride (BSH) in clinical trials. The work presented here, examines the performance of BSH in eight patients with Grade III and IV astrocytoma using a measurement technique which precisely correlates the boron uptake with the histology of the tumor and the peritumoral brain. Astrocytomas are exceptionally heterogeneous and spread migrating tumor cells into the surrounding brain. The patients were infused with 50 mg BSH per kilogram of body weight at 12, 18, 24 or 48 hours before surgery. At the time of operation, specimens were obtained of the tumor, skin, muscle, dura, blood, urine, and, when surgically possible, the brain adjacent to tumor. In three patients the intracellular boron distribution was investigated by subcellular fractionation. The blood clearance was biphasic with half-lives of 0.6 and 8.2 hours. After 3 days, approximately 70% of the dose injected was excreted in the urine. The maximum boron concentration in the tumor was 20 ppm, 12 hours after the infusion. The tumor-to-blood ratios ranged between 0.2 and 1.4, with the highest values after 18 to 24 hours. In the brain specimens the boron concentration never exceeded 1 ppm. This work confirms a selective uptake of boron in the tumor compared to the surrounding brain and that boron, to some extent, is incorporated in the tumor cells.
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| 58. |
- Chantzichristos, Dimitrios, 1976, et al.
(författare)
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Early Clinical Indicators of Addison’s Disease in Adults with Type 1 Diabetes: a Nationwide, Observational, Cohort Study
- 2019
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Ingår i: Journal of Clinical Endocrinology and Metabolism. - : The Endocrine Society. - 0021-972X .- 1945-7197. ; 104:4
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Tidskriftsartikel (refereegranskat)abstract
- Context Patients with type 1 diabetes mellitus (T1DM) have an increased risk of Addison disease (AD) development, but prediction of those at risk is not possible. Objective To determine whether there are early clinical indicators that may denote the development of AD in adults with T1DM. Design Observational, matched-cohort study. Setting Patient data from Swedish national registries [National Diabetes Register (NDR), Inpatient Register, and Prescription Drug Register]. Participants All patients with T1DM diagnosed with concomitant AD (n = 66) among the 36,514 adult patients with T1DM in the NDR between 1998 and 2013. Each case was matched to five controls with T1DM alone (n = 330). Main Outcome Measures Clinical data and drug prescriptions were assessed prior to baseline (inclusion into the study) and prior to AD diagnosis. Analysis of covariance and estimated group proportions were used for comparisons. Results Prior to baseline, cases had a higher frequency of thyroid/antithyroid drug prescription than controls (9.1% vs 1.8%). Prior to AD diagnosis, cases had higher frequencies of diabetic retinopathy (12.1% vs 2.1%), infections requiring hospital admission (16.7% vs 2.1%), thyroid/antithyroid drug prescription (28.8% vs 7.0%), and glucagon prescription (18.2% vs 6.4%). There was no difference in glycated Hb between the groups prior to baseline or prior to AD diagnosis. Conclusions These data suggest that medical treatment of thyroid disease, a severe infection, and glucagon prescription for severe hypoglycemia should raise the suspicion of AD development in adults with T1DM. Development of diabetic retinopathy might also be associated with glucocorticoid deficiency and the development of AD among patients with T1DM.
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| 59. |
- Chantzichristos, Dimitrios, 1976, et al.
(författare)
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Incidence, prevalence and seasonal onset variation of Addison's disease among persons with type 1 diabetes mellitus: nationwide, matched cohort studies.
- 2018
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Ingår i: European journal of endocrinology. - 1479-683X. ; 178:1, s. 115-122
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Tidskriftsartikel (refereegranskat)abstract
- We determined the incidence and prevalence of Addison's disease (AD) among persons with or without type 1 diabetes mellitus (T1DM) in nationwide, matched cohort studies.Persons with T1DM were identified from the Swedish National Diabetes Register and each was matched for age, sex, year and county to five controls randomly selected from the general population. Persons with AD were identified from the Swedish National Inpatient Register. Baseline demographics and seasonal onset variation of AD were presented by descriptive statistics. Prevalence and incidence were estimated by proportions and incidence rates, respectively. Times to AD were analyzed using the Cox proportional hazard model.Between 1998 and 2013, 66 persons with T1DM were diagnosed with AD at a mean age (s.d.) of 36.4 (13.0) years among 36 514 persons with T1DM, while 32 were diagnosed with AD at a mean age of 42.7 (15.2) years among 182 570 controls. The difference in mean age at diagnosis of AD between the groups was 6.3 years (P value = 0.036). The incidence of AD for a person with or without T1DM was therefore 193 and 18 per million person-years, respectively. The adjusted relative risk increase of developing AD in T1DM was 10.8 (95% CI: 7.1-16.5). The highest incidence of AD was observed during February-March and September-October. The prevalence of AD in persons with or without T1DM in December 2012 was 3410 and 208 per million, respectively. The odds ratio for AD in persons with T1DM vs controls was 16.5 (95% CI: 11.1-24.5).The risk to develop AD among persons with T1DM is more than 10 times higher than in persons without T1DM. Persons with T1DM develop AD at a younger age. The incidence of AD may have a seasonal pattern.
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| 60. |
- Chantzichristos, Dimitrios, 1976, et al.
(författare)
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Mortality in patients with diabetes mellitus and Addison's disease: a nationwide, matched, observational cohort study.
- 2017
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Ingår i: European journal of endocrinology. - 1479-683X. ; 176:1, s. 31-39
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Tidskriftsartikel (refereegranskat)abstract
- Our hypothesis was that patients with diabetes mellitus obtain an additional risk of death if they develop Addison's disease (AD).Nationwide, matched, observational cohort study cross-referencing the Swedish National Diabetes Register with Inpatient, Cancer and Cause of Death Registers in patients with diabetes (type 1 and 2) and AD and matched controls with diabetes. Clinical characteristics at baseline, overall, and cause-specific mortality were assessed. The relative risk of death was assessed using a Cox proportional hazards regression model.Between January 1996 and December 2012, 226 patients with diabetes and AD were identified and matched with 1129 controls with diabetes. Median (interquartile range) follow-up was 5.9 (2.7-8.6) years. When patients with diabetes were diagnosed with AD, they had an increased frequency of diabetes complications, but both medical history of cancer and coronary heart disease did not differ compared with controls. Sixty-four of the 226 patients with diabetes and AD (28%) died, while 112 of the 1129 controls (10%) died. The estimated relative risk increase (hazard ratio) in overall mortality in the diabetes and AD group was 3.89 (95% confidence interval 2.84-5.32) compared with controls with diabetes. The most common cause of death was cardiovascular in both groups, but patients with diabetes and AD showed an increased death rate from diabetes complications, infectious diseases and unknown causes.Patients with the rare combination of diabetes and AD showed a markedly increased mortality and died more frequently from infections and unknown causes than patients with diabetes alone. Improved strategy for the management of this combination of metabolic disorders is needed.
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