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MS SPIDOC is a novel sample delivery system designed for single (isolated) particle imaging at X-ray Free-Electron Lasers that is adaptable towards most large-scale facility beamlines. Biological samples can range from small proteins to MDa particles. Following nano-electrospray ionization, ionic samples can be m/z-filtered and structurally separated before being oriented at the interaction zone. Here, we present the simulation package developed alongside this prototype. The first part describes how the front-to-end ion trajectory simulations have been conducted. Highlighted is a quadrant lens; a simple but efficient device that steers the ion beam within the vicinity of the strong DC orientation field in the interaction zone to ensure spatial overlap with the X-rays. The second part focuses on protein orientation and discusses its potential with respect to diffractive imaging methods. Last, coherent diffractive imaging of prototypical T = 1 and T = 3 norovirus capsids is shown. We use realistic experimental parameters from the SPB/SFX instrument at the European XFEL to demonstrate that low-resolution diffractive imaging data (q < 0.3 nm -1 ) can be collected with only a few X-ray pulses. Such low-resolution data are sufficient to distinguish between both symmetries of the capsids, allowing to probe low abundant species in a beam if MS SPIDOC is used as sample delivery., (© 2023. The Author(s).)

Spontaneous Listeria peritonitis is well described in liver failure, but is uncommon in peritoneal dialysis patients. Atypical cases where peritonitis symptoms develop after systemic manifestations are rare and challenging for diagnostic. A 57-year-old peritoneal dialysis patient with history of ethylic cirrhosis was admitted after epileptic seizure. On admission, patient was soporous without signs of peritonitis and meningitis. Patient's peritoneal effluent was clear, with normal leukocytes. Cranial CT scan showed no abnormalities. Laboratory exams revealed positive inflammatory syndrome. Despite antibiotic therapy, next day, symptoms aggravated with coma development. Peritoneal effluent became cloudy and its leukocyte count rose up. Effluent microscopy revealed Gram-positive bacilli. Patient was started with intraperitoneal Vancomycin and Amikacin. Patient's clinical condition deteriorated with lethal outcome. Post-mortem analysis of effluent and blood culture showed growth of L. monocytogenes. Apart from idiopathic etiology, goat-milk curd, that patient had started consuming 10 days before admission, could theoretically be considered as possible infection vehicle. L. monocytogenes peritonitis in peritoneal dialysis patients is rare, but must be considered in immunocompromised or patients with concomitant liver failure, especially after Gram-positive bacilli identification in peritoneal effluent. In case of suspiscion of Listeria peritonitis, Ampicillin should be initiated, because bacteria often poorly respond to currently recommended empiric regimens.

Introduction: The inferior vena cava collapsibility index is a sign of hypervolemia in hemodialysis patients. Asymptomatic pericardial effusion in these patients can be either a sign of hypervolemia or bad systolic function of the left ventricle, or both. The aim of this study was to assess the incidence of asymptomatic pericardial effusion and its correlation to collapsibility index in haemodialysis patients during 2-year follow-up., Results: Of 115 consecutive hemodialysis patients, at the beginning of the study and on every 6 months we performed: clinical, ECG, echocardiography, laboratory assessment. There was 29 patients with asymptomatic pericardial effusion (25.21%) vs. 86 (74.79%) without asymptomatic pericardial effusion. There was no significant difference considering gender, age, vintage of HD between the groups. Colapsibillity index was statistically significantly lower among the patients with asymptomatic pericardial effusion: 0.39+/-0.09 vs. 0.69+/-0.21 in those without it; p<0.001. Asymptomatic pericardial effusion correlated inversely with colapsibillity index (r=-0.577; p<0.0001) and ejection fraction of left ventricle (r=-0.282; p<0.030) and positively with the dimension of left ventricle in diastole. The colapsibillity index had inverse correlation with asymptomatic pericardial effusion (r=-0.668; p<0.0001), end-diastolic dimension of the left ventricle (r=-0.464; p<0.0001), and only one positive correlation with Kt/V (r=0.294, p<0.002). During the follow-up, 16 pts (13.91%) died: 7 of them had a symptomatic pericardial effusion (43.75%). Factors with greatest relative risk for death were: persistent asymptomatic pericardial effusion (3.48); systolic dysfunction at the second examination (2.95): heart failure (2.88) at the third., Conclusion: Colapsibillity index and asymptomatic pericardial effusion are the closely correlated in inverse manner and both are the sign of hypervolemia. Asymptomatic pericardial effusion is also a sign of a bad systolic function and a very bad prognosis.

Atherosclerosis is significant risk factor for cardiovascular morbidity and mortality in dialysis patients. Aim of the study was ultrasound evaluation of intima media thickness on carotid arteries (as a marker of atherosclerosis), in dialysis patients and its correlation with proposed risk factors. Intima media thickness was measured in 45 dialysis patients with no signs of cardiovascular diseases (15 on peritoneal dialysis, group I, 30 on hemodialysis, group II) and 20 healthy controls. The mean carotid artery intima media thickness was significantly higher in dialysis patients than in control group. According to intima media thickness, dialysis patients were divided in group A (patient with intima media thickness less or equal 0.720 mm) and group B (intima media thickness higher then 0.720 mm). Intima media thickness in bout group was correlated with proposed risk factors. In group A there was not significant correlation of intima media thickness with risk factors. In group B significant correlation have been found between intima media thickness and LDL, VLDL cholesterol, body mass index and systolic, diastolic and mean blood pressure. Although atherosclerosis was not the only cause for cardiovascular morbidity and mortality, it has a dominant role in dialysis patients. Augmented intima media thickness could be early marker of atherosclerosis. The risk factors of great influence on intima media thickness are lipid disturbances, obesity and hypertension.

Introduction: Atherosclerosis is a major risk factor for increased cardiovascular morbidity and mortality in dialysis patients. First clinical symptoms are usually associated with initial atherosclerotic changes of blood vessels. The aim of this study was ultrasound evaluation of intima media thickness (IMT) of carotid arteries in dialysis patients and its correlation with certain risk factors., Patients and Methods: IMT was measured in 45 dialysis patients with no signs of cardiovascular diseases: 15 continuous ambulatory peritoneal dialysis (CAPD) patients, 30 hemodialysis (HD) patients and in 20 healthy controls. IMT was correlated with certain risk factors for atherosclerosis (general parameters--age, gender, duration of dialysis, cause of renal diseases, parameters of nutrition, parameters of calcium and phosphorus metabolism, lipid parameters, blood pressure and smoking)., Results: The mean carotid artery IMT was significantly higher in dialysis patients than in the control group (p < 0.05). In addition, the mean IMT was statistically significantly higher in PD than in HD patients (p < 0.05). In CAPD patients there was a significant correlation between IMT and total and LDL cholesterol. In the second group (HD patients) IMT significantly correlated with diastolic blood pressure, BMI and smoking., Conclusion: Although atherosclerotic cardiovascular disease may not manifest in dialysis patients, IMT of carotid arteries significantly increases. Major risk factors affecting IMT are lipid disturbances in patients on peritoneal dialysis and hypertension, obesity and smoking in HD patients.