Ultrasonography of quadriceps femoris muscle and subcutaneous fat tissue and body composition by BIVA in chronic dialysis patients

Protein Energy Wasting (PEW) in hemodialysis (HD) patients is a multifactorial condition due to specific pathology-related pathogenetic mechanisms, leading to loss of skeletal muscle mass in HD patients. Computed Tomography and Magnetic Resonance Imaging still represent the gold standard techniques for body composition assessment. However, their widespread application in clinical practice is difficult and body composition evaluation in HD patients is mainly based on conventional anthropometric nutritional indexes and bioelectrical impedance vector analysis (BIVA). Little data is currently available on ultrasound (US)-based measurements of muscle mass and fat tissue in this clinical setting. The purpose of our study is to ascertain: (1) if there are differences between quadriceps rectus femoris muscle (QRFM) thickness and abdominal/thigh subcutaneous fat tissue (SFT) measured by US between HD patients and healthy subjects; (2) if there is any correlation between QRFM and abdominal/thigh SFT thickness by US, and BIVA/conventional nutritional indexes in HD patients. We enrolled 65 consecutive HD patients and 33 healthy subjects. Demographic and laboratory were collected. The malnutrition inflammation score (MIS) was calculated. Using B-mode US system, the QRFM and SFT thicknesses were measured at the level of three landmarks in both thighs (superior anterior iliac spine, upper pole of the patella, the midpoint of the tract included between the previous points). SFT was also measured at the level of the periumbilical point. The mono frequency (50 KHz) BIVA was conducted using bioelectrical measurements (Rz, resistance; Xc, reactance; adjusted for height, Rz/H and Xc/H; PA, phase angle). 58.5% were men and the mean age was 69 (SD 13.7) years. QRFM and thigh SFT thicknesses were reduced in HD patients as compared to healthy subjects (p < 0.01). Similarly, also BIVA parameters, expression of lean body mass, were lower (p < 0.001), except for Rz and Rz/H in HD patients. The average QRFM thickness of both thighs at top, mid, lower landmarks were positively correlated with PA and body cell mass (BCM) by BIVA, while negatively correlated with Rz/H (p < 0.05). Abdominal SFT was positively correlated with PA, BCM and basal metabolic rate (BMR) (p < 0.05). Our study shows that ultrasound QRFM and thigh SFT thicknesses were reduced in HD patients and that muscle ultrasound measurements were significantly correlated with BIVA parameters

Plasma and red blood cell pufas in home parenteral nutrition paediatric patients—effects of lipid emulsions

Background: Mixed lipid emulsions (LE) containing fish oil present several advantages compared to the sole soybean oil LE, but little is known about the safety of essential fatty acids (EFA) profile in paediatric patients on long-term Parenteral Nutrition (PN). Aim of the study: to assess glycerophosfolipid polyunsaturated fatty acids (PUFA) levels on plasma and red blood cell (RBC) membrane of children on long term PN with composite LE containing fish oil (SMOF), and to compare it with a group receiving olive oil LE (Clinoleic®) and to the reference range for age, previously determined on a group of healthy children. Results: A total of 38 patients were enrolled, median age 5.56 (0.9–21.86) years, 15 receiving Clinoleic®, 23 receiving SMOF. Patients on SMOF showed significantly higher levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), lower levels of arachidonic acid (ARA) and Mead acid (MEAD)/ARA ratio in plasma and RBC compared with patients on Clinoleic® and with healthy children. Triene:tetraene (T:T) ratio of both groups of patients did not differ from that of healthy children-median plasma (MEAD/ARA: 0.01, interquartile rage (IQR) 0.01, p = 0.61 and 0.02, IQR 0.02, p = 0.6 in SMOF and Clinoleic® patients, respectively), and was considerably lower than Holman index (>0.21). SMOF patients showed no statistically significant differences in growth parameters compared with Clinoleic® patients. Patients of both groups showed stiffness class F0-F1 of liver stiffness measure (LSM) 5.6 (IQR 0.85) in SMOF patients and 5.3 (IQR 0.90) in Clinoleic® patients, p = 0.58), indicating absence of liver fibrosis. Conclusions: Fatty acids, measured as concentrations (mg/L), revealed specific PUFA profile of PN patients and could be an accurate method to evaluate nutritional status and eventually to detect essential fatty acid deficiency (EFAD). SMOF patients showed significantly higher EPA, DHA and lower ARA concentrations compared to Clinoleic® patients. Both LEs showed similar hepatic evolution and growth

On Comon's and Strassen's conjectures

Comon's conjecture on the equality of the rank and the symmetric rank of a symmetric tensor, and Strassen's conjecture on the additivity of the rank of tensors are two of the most challenging and guiding problems in the area of tensor decomposition. We survey the main known results on these conjectures, and, under suitable bounds on the rank, we prove them, building on classical techniques used in the case of symmetric tensors, for mixed tensors. Finally, we improve the bound for Comon's conjecture given by flattenings by producing new equations for secant varieties of Veronese and Segre varieties

On the birational geometry of conic bundles over the projective space

Let π:Z→Pn−1 be a general minimal n-fold conic bundle with a hypersurface BZ⊂Pn−1 of degree d as discriminant. We prove that if d≥4n+1 then −KZ is not pseudo-effective, and that if d=4n then none of the integral multiples of −KZ is effective. Finally, we provide examples of smooth unirational n-fold conic bundles π:Z→Pn−1 with discriminant of arbitrarily high degree.Let (Formula presented.) be a general minimal n-fold conic bundle with a hypersurface (Formula presented.) of degree d as discriminant. We prove that if (Formula presented.), then (Formula presented.) is not pseudo-effective, and that if (Formula presented.), then none of the integral multiples of (Formula presented.) is effective. Finally, we provide examples of smooth unirational n-fold conic bundles (Formula presented.) with a discriminant of arbitrarily high degree

Birational geometry of moduli spaces of configurations of points on the line

In this paper, we study the geometry of GIT configurations of n ordered points on P1 both from the birational and the biregular viewpoint. In particular, we prove that any extremal ray of the Mori cone of effective curves of the quotient.P1/n== PGL.2/, taken with the symmetric polarization, is generated by a one dimensional boundary stratum of the moduli space. Furthermore, we develop some technical machinery that we use to compute the canonical divisor and the Hilbert polynomial of.P1/n== PGL.2/ in its natural embedding, and its automorphism group

Cox rings of blow-ups of multiprojective spaces

Let Xr1,n be the blow-up of P1× Pn in r general points. We describe the Mori cone of Xr1,n for r≤ n+ 2 and for r= n+ 3 when n≤ 4 . Furthermore, we prove that Xn+11,n is log Fano and give an explicit presentation for its Cox ring

Predicting the human behaviour in human-robot co-assemblies: An approach based on suffix trees

Prediction of the human behaviour is essential for allowing an efficient human-robot collaboration. This was confirmed recently showing how scheduling approaches can significantly increase the productivity of a robotic cell by planning the robotic actions in a way as much as possible compliant with the human predicted behaviour. This work proposes an innovative approach for human activity prediction, exploiting both a-priori information and knowledge revealed during operation. The resulting approach is proved to achieve good performance through both off-line simulated sequences and in a realistic co-assembly involving a human operator and a dual arm collaborative robot

Temporal prediction of touch instant during observation of human and robot grasping.

The aim of the present work was to test the ability to predict the instant at which a grasping hand touches an object. Our hypothesis was that, because of the activation of the mirror-neuron system, the same predictive process necessary for action execution should be active during observation. Experimental evidence indicates, however, that not only observed actions but also observed objects automatically activate observer's motor repertoire. What happens, therefore, if the observed action is different from the one automatically evoked by the vision of the object? To answer this question we presented subjects with two different grasping actions: the one most suitable for the presented object and a less appropriate one. Subjects were required to detect the instant at which the demonstrator's hand touched the object. In a further condition, subjects were required to detect the outcome of an action performed by a robotic arm moving with constant kinematics. Results showed that while in the case of robot grasping subjects responded before the touch instant, in the case of human grasping the response followed the touch instant, but occurred much earlier than simple reaction times. This demonstrates that subjects were able to predict the outcome of the seen action. The predictive capability was specifically enhanced during observation of the "suitable" grasping. We interpret these results as an indication of the synergic contribution of both object-related (canonical) and action-related (mirror) neurons during observation of actions directed towards graspable objects

Synthesis and in vitro cytotoxicity of deoxyadenosine-​bile acid conjugates linked with 1,​2,​3-​triazole

We report herein the synthesis and biol. evaluation of novel deoxynucleoside-​bile acid conjugates linked through a 1,​2,​3-​triazole ring. The conjugates were synthesized via Cu(i) mediated 1,​3-​dipolar cycloaddn. reaction ('click' chem.) of 3-​azido bile acid derivs. and terminal alkyne moieties linked to the C-​8 position of deoxyadenosine. All novel mols. were evaluated in vitro for their anti-​proliferative activity against four human cell lines (i.e., leukemic T Jurkat and K562; colon carcinoma HCT116; and ovarian cancer A2780) and their cytotoxicity toward human fibroblast cells. Several conjugates exhibited strong anti-​proliferative activity against human leukemia T cells. The best cytotoxicity was obsd. for HdA-​CDC on both leukemia cell lines with IC50 up to 8.51 μM. The apoptotic activity of several conjugates was also established