The Quiescent X-Ray Spectrum of the Neutron Star in Cen X-4 Observed with Chandra/ACIS-S

We report on spectral and intensity variability analysis from a Chandra/ACIS-S observation of the transient, type-I X-ray bursting low-mass X-ray binary Cen X-4. The quiescent X-ray spectrum during this observation is statistically identical to one observed previously with Beppo/SAX, and close, but not identical, to one observed previously with ASCA. The X-ray spectrum is best described as a pure Hydrogen atmosphere thermal spectrum plus a power-law component that dominates the spectrum above 2 keV. The best-fit radius of the neutron star is r=12.9+/-2.6 (d/1.2 kpc) km if the interstellar absorption is fixed at the value implied by the optical reddening. Allowing the interstellar absorption to be a free parameter yields r=19+45-10 (d/1.2 kpc) km (90% confidence). The thermal spectrum from the neutron star surface is inconsistent with a solar metallicity. We find a 3sigma upper-limit of root-mean-square variability <18% (0.2-2.0 keV; 0.0001-1 Hz) during the observation. On the other hand, the 0.5-10.0 keV luminosity decreased by 40+/-8% in the 4.9 years between the Asca and Chandra observations. This variability can be attributed to the power-law component. Moreover, we limit the variation in thermal temperature to <10% over these 4.9 years. The stability of the thermal temperature and emission area radius supports the interpretation that the quiescent thermal emission is due to the hot neutron star core.Comment: 25 pages, 1 figure; ApJ, Accepted for April 10 2001 Issu

Reference programme: Diagnosis and treatment of headache disorders and facial pain. Danish Headache Society, 2nd Edition, 2012

Headache and facial pain are among the most common, disabling and costly disorders in Europe. Correct diagnosis and treatment is important for achieving a high quality of care. As a national organisation whose role is to educate and advocate for the needs of patients with primary headaches, the Danish Headache Society has set up a task force to develop a set of guidelines for the diagnosis, organisation and treatment of the most common types of headaches and for trigeminal neuralgia in Denmark. The guideline was published in Danish in 2010 and has been a great success. The Danish Headache Society decided to translate and publish our guideline in English to stimulate the discussion on optimal organisation and treatment of headache disorders and to encourage other national headache authorities to produce their own guidelines. The recommendations regarding the most common primary headaches and trigeminal neuralgia are largely in accordance with the European guidelines produced by the European Federation of Neurological Societies. The guideline provides a practical tool for use in daily clinical practice for primary care physicians, neurologists with a common interest in headache, as well as other health-care professionals treating headache patients. The guideline first describes how to examine and diagnose the headache patient and how headache treatment is organised in Denmark. This description is followed by individual sections on the characteristics, diagnosis, differential diagnosis and treatment of each of the major headache disorders and trigeminal neuralgia. The guideline includes many tables to facilitate a quick overview. Finally, the particular problems regarding headache in children and headache in relation to female hormones and pregnancy are described

Binary systems and their nuclear explosions

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Genetic background determines renal response to chronic lithium treatment in female mice.

Chronic lithium treatment for bipolar disease causes mainly side effects in the kidney. A subset of lithium users develops nephrogenic diabetes insipidus (NDI), a urinary concentrating disorder, and chronic kidney disease (CKD). Age, lithium dose, and duration of treatment are important risk factors, whereas genetic background might also play an important role. To investigate the role of genetics, female mice of 29 different inbred strains were treated for 1 year with control or lithium chow and urine, blood, and kidneys were analyzed. Chronic lithium treatment increased urine production and/or reduced urine osmolality in 21 strains. Renal histology showed that lithium increased interstitial fibrosis and/or tubular atrophy in eight strains, whereas in none of the strains glomerular injury was induced. Interestingly, lithium did not elevate urinary albumin-creatinine ratio (ACR) in any strain, whereas eight strains even demonstrated a lowered ACR. The protective effect on ACR coincided with a similar decrease in urinary IgG levels, a marker of glomerular function, whereas the adverse effect of lithium on interstitial fibrosis/tubular atrophy coincided with a severe increase in urinary β2-microglobulin (β2M) levels, an indicator of proximal tubule damage. Genetic background plays an important role in the development of lithium-induced NDI and chronic renal pathology in female mice. The strong correlation of renal pathology with urinary β2M levels indicates that β2M is a promising biomarker for chronic renal damage induced by lithium

Lithium reduces blood glucose levels, but aggravates albuminuria in BTBR-<i>ob/ob</i> mice

<div><p>Glycogen synthase kinase 3 (GSK3) plays an important role in the development of diabetes mellitus and renal injury. GSK3 inhibition increases glucose uptake in insulin-insensitive muscle and adipose tissue, while it reduces albuminuria and glomerulosclerosis in acute kidney injury. The effect of chronic GSK3 inhibition in diabetic nephropathy is not known. We tested the effect of lithium, the only clinical GSK3 inhibitor, on the development of diabetes mellitus and kidney injury in a mouse model of diabetic nephropathy. Twelve-week old female BTBR-<i>ob/ob</i> mice were treated for 12 weeks with 0, 10 and 40 mmol LiCl/kg after which the development of diabetes and diabetic nephropathy were analysed. In comparison to BTBR-WT mice, <i>ob/ob</i> mice demonstrated elevated bodyweight, increased blood glucose/insulin levels, urinary albumin and immunoglobulin G levels, glomerulosclerosis, reduced nephrin abundance and a damaged proximal tubule brush border. The lithium-10 and -40 diets did not affect body weight and resulted in blood lithium levels of respectively <0.25 mM and 0.48 mM. The Li-40 diet fully rescued the elevated non-fasting blood glucose levels. Importantly, glomerular filtration rate was not affected by lithium, while urine albumin and immunoglobulin G content were further elevated. While lithium did not worsen the glomerulosclerosis, proximal tubule function seemed affected by lithium, as urinary NGAL levels were significantly increased. These results demonstrate that lithium attenuates non-fasting blood glucose levels in diabetic mice, but aggravates urinary albumin and immunoglobulin G content, possibly resulting from proximal tubule dysfunction.</p></div

Analysis of glomerular injury upon lithium treatment.

<p>12-week old female BTBR-WT and -<i>ob/ob</i> mice received standard chow or chow with lithium supplementation (10 or 40 LiCl mmol/kg) for 12 weeks. After sacrifice, kidneys were isolated and the absence (A) or presence of moderate (B) or severe (C) mesangial matrix expansion was determined using PAS staining. Moderate and severe mesangial matrix expansion was defined as an increased presence of mesangial matrix (indicated by stars) with the moderate form still having some open capillary lumens (indicated by arrows) while these are basically absent in the severe form. Scale bar indicates 10 μM. The percentage of glomeruli with moderate or severe mesangial matrix expansion was scored as follows: 0) 0–1%, 1) 1–5%, 2) 5–20%, 3) 20–50%, 4) >50% (D and E), n = 9 per group. Kidney lysates were used to determine nephrin abundance via immunoblotting (F) and subsequent semi-quantification (G), n = 9 per group. *p<0.05; ***p<0.001. Cm, Coomassie.</p

The effect of lithium on GFR, BUN, and urinary albumin and IgG levels.

<p>12-week old female BTBR-WT and -ob/ob mice received standard chow or chow with lithium supplementation (10 or 40 mmol LiCl/kg) for 12 weeks. After 11 weeks of treatment, mice received a FITC-inulin bolus injection. Inulin clearance was determined via the decay of FITC-inulin in blood (A). At the time of sacrifice, blood was isolated and BUN was determined (B), while spot urine was collected earlier that week to determine (C) albumin-creatinine ratio and (D) IgG content, n = 9 per group. *p<0.05; ***p<0.001; ACR, albumin-creatinine ratio.</p

The effect of lithium on blood glucose and insulin levels.

<p>12-week old female BTBR-WT and -<i>ob/ob</i> mice received standard chow or chow with lithium supplementation (10 or 40 mmol LiCl/kg) for 12 weeks. Two weeks before sacrifice, mice were fasted for 4 hours, after which they received an intraperitoneal injection of 2 mg glucose/g bodyweight. Blood was collected before and 15 minutes after injection and blood glucose levels were determined (A). At the time of sacrifice blood was collected to analyze non-fasting (B) glucose and (C) insulin levels, n = 9 per group. *p<0.05; **p<0.01; ***p<0.001.</p

The effect of lithium on cortical αSMA, CTGF and TGFβ mRNA levels.

<p>12-week old female BTBR-WT and -<i>ob/ob</i> mice received standard chow or chow with lithium supplementation (10 or 40 LiCl/kg) for 12 weeks. After RNA isolation from cortex, mRNA levels of (A) αSMA, (B) CTGF and (C) TGFβ were determined by qPCR using 36B4 as a housekeeping gene. *p<0.05; **p<0.01.</p