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We present a summary of the splinter session 'Sun-like stars unlike the Sun' that was held on June 9, 2016, as part of the Cool Stars 19 conference (Uppsala, Sweden), in which the main limitations (in the theory and observations) in the derivation of very precise stellar parameters and chemical abundances of Sun-like stars were discussed. The most important and most debated processes that can produce chemical peculiarities in solar-type stars were outlined and discussed. Finally, in an open discussion between all the participants, we tried to identify new pathways and prospects toward future solutions of the currently open questions. [ABSTRACT FROM AUTHOR]

Objective: Cerebral white-matter changes (WMCs) are frequently found in dementia and have been proposed to be related to vascular factors and a certain symptomatological profile. However, few studies have included both vascular factors and a broad spectrum of cognitive, neurological and psychiatric symptoms, easily detectable by the physician in the everyday clinical work. The objective was to study the relationships between WMCs on MRI/CT and neuropsychiatric symptoms and vascular factors in patients with cognitive impairment. Methods: One hundred and seventy-six patients with Alzheimer's disease, vascular dementia, mixed dementia, and mild cognitive impairment were included. All patients underwent a standardized examination including medical history, clinical examinations, laboratory tests and brain imaging (CT or MRI). The identification and severity degree of WMCs was assessed blindly to clinical findings, using a semi-quantitative scale. For statistical analyses, patients were grouped based on absence or presence of WMCs. Significant variables in bivariate analyses were included as predictors in stepwise multiple logistic regression analyses. Results: Bivariate analyses showed significant associations between WMCs and age, gender, blood pressure, hypertension, ischaemic heart disease and TIA/RIND. Furthermore, there were significant associations between WMCs and apathy, mental slowness, disinhibition, gait disturbance and focal neurologic symptoms. The multivariate logistic model revealed apathy, mental slowness and age as the most consistent predicting factors for WMCs, together with MRI as a radiological method for the detection of WMCs. Conclusions: The findings indicate that WMCs in patients with dementia are associated with a dysexecutive-related behavioural symptom profile, vascular factors related to small and large vessel diseases and age. [ABSTRACT FROM AUTHOR]

From stellar spectra, a variety of physical properties of stars can be derived. In particular, the chemical composition of stellar atmospheres can be inferred from absorption line analyses. These provide key information on large scales, such as the formation of our Galaxy, down to the small-scale nucleosynthesis processes that take place in stars and supernovae. By extending the observed wavelength range toward bluer wavelengths, we optimize such studies to also include critical absorption lines in metal-poor stars, and allow for studies of heavy elements ( Z ≥ 38) whose formation processes remain poorly constrained. In this context, spectrographs optimized for observing blue wavelength ranges are essential, since many absorption lines at redder wavelengths are too weak to be detected in metal-poor stars. This means that some elements cannot be studied in the visual-redder regions, and important scientific tracers and science cases are lost. The present era of large public surveys will target millions of stars. It is therefore important that the next generation of spectrographs are designed such that they cover a wide wavelength range and can observe a large number of stars simultaneously. Only then, we can gain the full information from stellar spectra, from both metal-poor to metal-rich ones, that will allow us to understand the aforementioned formation scenarios in greater detail. Here we describe the requirements driving the design of the forthcoming survey instrument 4MOST, a multi-object spectrograph commissioned for the ESO VISTA 4 m-telescope. While 4MOST is also intended for studies of active galactic nuclei, baryonic acoustic oscillations, weak lensing, cosmological constants, supernovae and other transients, we focus here on high-density, wide-area survey of stars and the science that can be achieved with high-resolution stellar spectroscopy. Scientific and technical requirements that governed the design are described along with a thorough line blending analysis. For the high-resolution spectrograph, we find that a sampling of ≥2.5 (pixels per resolving element), spectral resolution of 18000 or higher, and a wavelength range covering 393-436 nm, is the most well-balanced solution for the instrument. A spectrograph with these characteristics will enable accurate abundance analysis (±0.1 dex) in the blue and allow us to confront the outlined scientific questions. (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Background and purpose: White matter lesions (WMLs) caused by small vessel disease are common in elderly people and contribute to cognitive impairment. There are no established biochemical markers for WMLs. We aimed to study the relation between degree of WMLs rated on magnetic resonance imaging of the brain and cerebrospinal fluid (CSF) levels of structural biomarkers associated with Alzheimer’s disease (AD) and subcortical vascular dementia. Methods: Fifty-three non-demented elderly individuals with WMLs were subjected to lumbar puncture. Degree of WMLs was rated using the Fazekas scale. Volumetric assessment of WMLs was performed. CSF samples were analyzed for the 40 and 42 amino acid fragments of amyloid β, α- and β-cleaved soluble amyloid precursor protein, total tau (T-tau), hyperphosphorylated tau (P-tau181), neurofilament light protein (NFL), sulfatide and CSF/Serum-albumin ratio. Results: Fifteen subjects had mild, 23 had moderate and 15 had severe degree of WMLs . CSF-NFL levels differed between the groups ( P < 0.001) and correlated with the volume of WMLs ( r = 0.477, P < 0.001). CSF sulfatide concentration displayed similar changes but less strongly. T-tau, P-tau181 and the different amyloid markers as well as CSF/S-albumin ratio did not differ significantly between the groups. Conclusions: The association of increased CSF-NFL levels with increasing severity of WMLs in non-demented subjects suggests that NFL is a marker for axonal damage in response to small vessel disease in the brain. This manifestation may be distinct from or earlier than the neurodegenerative process seen in AD, as reflected by the lack of association between WMLs and AD biomarkers. [ABSTRACT FROM AUTHOR]

Objectives – The aim of the study was to visualize cortical function in Parkinson’s patients with various degrees of cognitive impairment. Materials and methods – Thirty-seven patients with Parkinson’s disease and three with Parkinson plus syndromes underwent cognitive assessment and rCBF using 99mTC-HMPAO-SPECT. Results – Almost no regional reductions in cerebral blood flow were seen in patients without cognitive impairment ( n = 16). Limited, mainly posterior, blood flow reductions were seen in patients with mild cognitive impairment ( n = 14), whereas the reductions were extensive and bilaterally symmetric, involving both anterior and posterior brain regions in patients with dementia ( n = 10). Conclusions – The findings suggest a widespread cortical, mainly posterior type of dysfunction and a relationship between the degree of cognitive impairment and the magnitude of the dysfunction. [ABSTRACT FROM AUTHOR]

ObjectivesThe aim of the present study was to elucidate a possible relationship between depressive symptomatology and regional brain symptomatology in demented patients. Methods170 consecutive inpatients were studied. They suffered from Alzheimer's disease (103 patients), vascular dementia (48 patients), or frontotemporal dementia (19 patients). The patients underwent a neuropsychiatric investigation, which included assessments of (1) depression, and (2) regional brain symptomatology. Depressive symptomatology was assessed as presence of (a) depressed mood, and (b) anxiety. In the further statistical analysis, the presence of depressed mood and/or anxiety was also evaluated. The principle of the regional symptom analysis was the successive aggregation of observable symptom variables, leading to the final determination of four possible regional brain syndromes (frontal, subcortical, parietal and global), by way of the Stepwise comparative status analysis (STEP). The possible correlations between regional brain symptomatology and depressive symptomatology were analysed by means of (a) χ[sup 2] statistics, and (b) a logistic regression analysis in which confounding factors were included (age, degree of dementia, duration). ResultsThe subcortical syndrome correlated with depressed mood (χ[sup 2] , p = 0.002; logistic regression, p = 0.002). A negative correlation was noted between the parietal syndrome and depressed mood (p = 0.010 and p = 0.013, respectively). No other significant correlations between presence of regional brain syndrome and presence of depressive symptomatology could be seen. ConclusionsDemented patients with a clinically established subcortical dysfunction appear to be more susceptible to depressive symptomatology. The results of this study also suggest that posterior brain dysfunction in dementia is not correlated with depressive symptomatology. Copyright © 2002 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In a prospective, randomised, multicentre study, 112 patients with Achilles tendon rupture (ATR) were allocated to surgical treatment ( n=59), followed by early functional rehabilitation using a brace, and non-surgical treatment ( n=53), i.e. eight weeks of plaster treatment. In this study, the results of the isokinetic muscle strength evaluation are presented for contractions in both the concentric and the eccentric mode, plantar flexion and dorsiflexion, two angular velocities and three different positions of the subject. The heel-raise test for endurance, maximum calf circumference and tendon width were also evaluated. The re-rupture rate was 20.8% in the non-surgically-treated group and 1.7% in the surgically-treated group. No significant differences were found between the treatment groups in terms of the isokinetic strength measurements and the endurance test among the patients who did not sustain a re-rupture. If a re-rupture is avoided, both surgical and non-surgical treatment for ATR produce good functional outcome; however, the muscle function was not restored after two years in either group. [ABSTRACT FROM AUTHOR]

In the present study, the torque or work produced during isometric, pure concentric and eccentric–concentric plantar flexions, performed in sitting, standing and prone were measured. The electromyographic (EMG) activity was measured from the soleus, gastrocnemius medialis, tibialis anterior and rectus femoris muscles. The isometric tests showed the highest torques in the standing test. The rectus femoris and gastrocnemius activities were lower in the prone than in the standing test. The sitting test showed lower activities in all muscles of the lower leg compared with the standing test. No differences in work between the prone and sitting tests were found during the concentric phases. Higher rectus femoris activity in the eccentric–concentric test and lower activity in the triceps surae during the concentric phases were seen in the sitting compared with the prone test. We conclude that tests of overall functional ability should be performed in the standing position while specific tests of the plantar flexors should be performed in the prone position. [ABSTRACT FROM AUTHOR]

Functional outcome, stability at radiographic investigation and ankle joint torque after anatomical reconstruction of the lateral ankle ligaments were evaluated in patients with early postoperative mobilization versus those with cast immobilization. Thirty patients with chronic lateral ligament instability of the ankle underwent anatomical reconstruction of the ligaments. Postoperatively the patients were randomly allocated to two groups: Group A (n=15) were immobilized in a below-knee plaster for 6 weeks and Group B (n=15) underwent early controlled range of motion training using an Air-Cast® ankle brace. The functional results were evaluated using a scoring scale and objective results using standardized stress radiographs. Also eccentric and concentric muscle torque at 60°/s was measured in plantar flexion and dorsiflexion, respectively. The functional results were satisfactory in 12/15 ankles in Group A and 14/15 in Group B(n.s.). All the patients with satisfactory results regained normal range of motion. Patients with unsatisfactory results had either residual pain or recurrent instability. In Group B, the strength measurements revealed significantly higher peak torque values after three months in plantar flexion at 60°/s. Six months postoperatively, the torque values did not differ significantly between the groups. Also, there was no group difference in the laxity of the ankle joint, including both anterior talar translation test and talar tilt test, at the two-year follow-up. One patient had a superficial wound infection. We conclude that after the reconstruction of chronic lateral ligament instability of the ankle the functional and stability results were equally good with early postoperative mobilization and 6-week immobilization. However, using early mobilization plantar flexion strength was regained earlier than with cast immobilization, without any risk of short-or medium-term complications, such as increased ankle laxity. We recommend early [ABSTRACT FROM AUTHOR]

Non-fermenting mycoplasma species deplete culture media for arginine through arginase activity linked to their arginine deiminase pathway, resulting in proliferation arrest and cell death in mycoplasma-contaminated cell cultures. The presence of only 2-3 Mycoplasma (M.) arginini-contaminated T cells in a one-way allogeneic mixed-lymphocyte culture (MLC) significantly inhibits development of cytotoxic T-cell activity. Likewise, strong degrees of inhibition are observed after addition of monogram doses of M. arginini extracts (MAE) to MLC or cell proliferation cultures, M. arginini-induced cell inhibition can be reversed by addition of excess arginine to the culture medium. Antisera raised against non-fermenting, but not against fermenting, mycoplasma species block the inhibitory effect of MAE. SDS-PAGE separation of MAE disclosed a broad band at 60 kDa which contained arginase activity when assayed in MLC and cell proliferation culture. SDS PAGE followed by western blotting and reaction with antisera raised against non-fermenting mycoplasma species demonstrated a band at 43 kDa common for these micro-organisms. [ABSTRACT FROM AUTHOR]

Background & Aims: Endoscopic retrograde cholangiography (ERCP) has been considered the gold standard for the diagnosis and follow-up of primary sclerosing cholangitis, but it has been replaced by less invasive magnetic resonance imaging and cholangiopancreatography (MRI-MRCP). However, the role of these two techniques in the evaluation of disease activity and severity needs to be elucidated., Methods: Patients with primary sclerosing cholangitis (n: 48, male 31, median age: 35.7; 28.0-44.2) who underwent ERCP and MRI-MRCP within ±3 months for diagnosis or follow-up, were reviewed. ERCP and MRI-MRCP images were scored using the modified Amsterdam score. Serum and biliary cytology markers of disease activity and severity were related to the imaging findings. Agreement on the assessment of the ERCP/MRCP score was calculated by kappa-statistics. Spearman's ρ was calculated when appropriate., Results: The agreement between ERCP and MRCP in scoring bile duct changes for disease severity was only moderate (weighted kappa: 0.437; 95% CI: 0.211-0.644 for intra- and 0.512; 95% CI: 0.303-0.720 for extra-hepatic bile ducts). ERCP and MRCP intra-hepatic scores were associated to the surrogate marker alkaline phosphatase (P = .02 for both). A weak correlation between MRCP score for extra-hepatic bile ducts and liver transplantation/death was found (Spearman's ρ = .362, 95% CI: 0.080-0.590, P = .022). A weak correlation between intra- (Spearman's ρ = .322, 95% CI: 0.048-0.551, P = .022) and extra-hepatic (Spearman`s ρ = .319, 95% CI: 0.045-0.549, P = .025) peribiliary enhancement on contrast-enhanced MRI and severity of biliary cytologic classification was found., Conclusions: The overall agreement between ERCP and MRI-MRCP in assessing disease severity was moderate for intra- and extra-hepatic bile ducts. MRI-MRCP seems to have a minor role as surrogate marker of disease activity and progression in PSC., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)