Deamidation at Asparagine and Glutamine As a Major Modification upon Deterioration/Aging of Proteinaceous Binders in MuralPaintings

Proteomic strategies are herein proved to be a complementary approach to the well established amino acid composition analysis for the characterization of the aging and deterioration phenomena occurring to proteinaceous materials in works-of-art. Amino acid analyses on several samples demonstrated that proteins in the frescoes from the Camposanto Monumentale in Pisa are deteriorated as revealed by the decrease in Met, Lys, and Tyr content and by the presence in all the samples of amino malonic acid as a result of Ser, Phe, and Cys oxidation. Proteomic analysis identified deamidation at Asn and Gln as a further major event occurred. This work paves the way to the exploitation of proteomic strategies for the investigation of the molecular effects of aging and deterioration in historical objects. Results show that proteomic searches for deamidation by liquid chromatography-tandem mass spectrometry (LC-MS/MS) could constitute a routine analysis for paintings or any artistic and historic objects where proteins are present. Peptides that can be used as molecular markers when casein is present were identified

Nitrogen and energy partitioning in two genetic groups of pigs fed low-protein diets at 130 kg body weight

The aim was to evaluate the effect of low-protein (LP) or low-amino acid diets on digestibility, energy and nitrogen (N) utilisation in 2 genetic groups (GG) of pigs (129±11 kg BW). Duroc×Large White (A) pigs were chosen to represent a traditional GG for ham production, and Danbred Duroc (D) pigs to represent a GG with fast growing rate and high carcass lean yield. Dietary treatments: a conventional diet (CONV) containing 13.2% CP, and two LP diets, one with LP (10.4%) and low essential AA (LP1), the second with LP (9.7%) and high essential AA (LP2). Compared to CONV, LP2 had the same essential AA content per unit feed, while LP1 the same essential AA content per unit CP. Feed was restricted (DMI=6.8% BW0.75). Four consecutive digestibility/balances periods were conducted with 24 barrows, 12 A and 12 D. Metabolic cages and respiration chambers were used. No significant difference between diets was registered for digestibility. Nitrogen excreted: 41.3, 33.4 and 29.0 g/d (P=0.009), for CONV, LP1 and LP2 diets, respectively. Nitrogen retention was similar between the diets. Heat production (HP) was the lowest for LP diets. There was a tendency (P=0.079) for a lower energy digestibility in D group. The D pigs also had a higher HP and hence a lower retained energy in comparison with the A pigs. In conclusion: it is possible to reduce N excretion using very LP diets and LP-low AA diets; Danbred GG have a higher heat production and a lower energy retention than A pigs

SPS-assisted Synthesis of SICp reinforced high entropy alloys: reactivity of SIC and effects of pre-mechanical alloying and post-annealing treatment

In this work a traditional high entropy alloy (FeCoNiCrAl) was reinforced by uniformly distributed reactive silicon carbide (SiC) particles by a powder metallurgy synthetic route, using as precursors simply mixed powders or mechanically prealloyed ones. The reactive sintering produced a single isomorphic BCC structure. The sample microstructure resulted equiassic, more homogenous in samples based on prealloyed powders. The instability of SiC in the presence of metal precursors resulted in the formation of more stable carbides and silicides, as well as in carbon diffusion in the high entropy alloy matrix and partially unreacted SiC particles. The formation of these newly formed fine precipitates, as well as the presence of residual SiC were useful to increase the hardness of the alloy

BsmI, ApaI and TaqI Polymorphisms in the Vitamin D Receptor Gene (VDR) and Association with Lumbar Spine Pathologies: An Italian Case-Control Study.

Three adjacent single nucleotide polymorphisms of the vitamin D receptor gene (VDR) BsmI (rs1544410), ApaI (rs7975232), and TaqI (rs731236) are commonly studied in several pathologies. We aimed to evaluate the distribution of VDR BsmI, ApaI, and TaqI allele, genotype, and haplotype frequencies in an Italian cohort of 266 patients with lumbar spine disorders assessed by Magnetic Resonance Imaging and 252 asymptomatic controls. The exposure to putative risk factors was evaluated by a questionnaire. Polymorphisms were detected by PCR-RFLP and TaqMan\uae SNP Genotyping Assay. The results were statistically adjusted for the identified conventional risk factors. The three SNPs were in linkage disequilibrium. For all cases BbAaTT was a 3-fold risk factor OR = 3.38), whereas bbAATT (OR = 0.22), and bbaaTT (OR = 0.47) genotypes were found to be protective. Specifically, for patients affected by disc herniation only (n = 88) and all lumbar pathologies excluding stenosis and/or spondylolistesis (n = 215) B allele, Bb, Aa, and BbAaTT genotypes were risky, whereas b allele, bb, aa, and bbaaTT genotypes were protective. In patients affected by osteochondrosis with or without disc hernation (n = 50), T allele, Aa, and bbAaTT genotypes were risky, whereas t allele, AA, tt genotypes were protective. In patients affected by stenosis and/or spondylolistesis (n = 51) no significant associations were found. This is the first study showing an association of the three genetic VDR variants BsmI, ApaI, and TaqI and lumbar spine pathologies. Our study contributes to delineate genetic risk factors for specific subgroups of patients with lumbar spine pathologies highlighting the importance of haplotype analysis, and of detailed clinical evaluation of the patients for identification of genetic biomarkers

The influence of oscillations on energy estimates for damped wave models with time-dependent propagation speed and dissipation

The aim of this paper is to derive higher order energy estimates for solutions to the Cauchy problem for damped wave models with time-dependent propagation speed and dissipation. The model of interest is \begin{equation*} u_{tt}-\lambda^2(t)\omega^2(t)\Delta u +\rho(t)\omega(t)u_t=0, \quad u(0,x)=u_0(x), \,\, u_t(0,x)=u_1(x). \end{equation*} The coefficients $\lambda=\lambda(t)$ and $\rho=\rho(t)$ are shape functions and $\omega=\omega(t)$ is an oscillating function. If $\omega(t)\equiv1$ and $\rho(t)u_t$ is an "effective" dissipation term, then $L^2-L^2$ energy estimates are proved in [2]. In contrast, the main goal of the present paper is to generalize the previous results to coefficients including an oscillating function in the time-dependent coefficients. We will explain how the interplay between the shape functions and oscillating behavior of the coefficient will influence energy estimates.Comment: 37 pages, 2 figure

High entropy alloys obtained by field assisted powder metallurgy route: SPS and microwave heating

The aim of this work was to investigate the field assisted powder metallurgy route for producing HEAs at equimolar composition, i.e. FeCoNiCrAl, starting from metal powders. Both mixed, mechanically activated and mechanically alloyed powders have been used. The powders obtained by mechanical alloying were synthesized only by SPS, whereas the remaining ones were sintered by SPS or microwave heating. The investigated field assisted sintering techniques allowed an extremely short alloying time, high energy density on the load and negligible contamination by the surrounding environment. Both the conducted sintering-synthesis technology resulted not definitive to produce chemical homogeneity and to obtain a single stable structure. Thus a subsequently heat treatment was required. The post heat treatment, indeed, led to a single crystalline structure (FCC) and the material was fully recrystallized. After heat treatment samples are isomorphic: they exhibit two different phases with the same FCC cell, but different chemical composition, in detail Fe-Cr richer and Al-Ni richer. SPS-ed samples present a reduced porosity, while microwave processed ones are much more porous and this is reflected in the mechanical properties

High Levels of Circulating Type II Collagen Degradation Marker (CTx-II) Are Associated with Specific VDR Polymorphisms in Patients with Adult Vertebral Osteochondrosis

Both vitamin D and collagen have roles in osteocartilaginous homeostasis. We evaluated the association between the circulating 25-hydroxyvitamin D (25(OH)D) type I and II collagen degradation products (CTx-I, and CTx-II), and four vitamin D receptor gene (VDR) polymorphisms, in Italian males affected by low back pain (LBP) due to herniation/discopathy and/or vertebral osteochondrosis. FokI, BsmI, ApaI, and TaqI VDR-polymorphisms were detected through PCR-restriction fragment length polymorphism (RFLP), and circulating 25(OH)D, CTx-I and CTx-II were measured by immunoassays in 79 patients (of which 26 had osteochondrosis) and 79 age-, sex- and body mass index (BMI)-matched healthy controls. Among all 158 subjects, carriers of FF and Ff genotypes showed lower 25(OH)D than ff, which suggested a higher depletion of vitamin D in F allele carriers. Higher CTx-I concentrations were observed in TT versus Tt among controls, and Tt versus tt among LBP cases, which suggested a higher bone-cartilaginous catabolism in subjects bearing the T allele. Higher CTx-II concentrations were observed in patients with osteochondrosis bearing FF, bb, TT, or Aa genotypes in comparison with hernia/discopathy patients and healthy controls. Vertebral osteochondrosis shows peculiar genotypic and biochemical features related to vitamin D and the osteocartilaginous metabolism. Vitamin D has roles in the pathophysiology of osteochondrosis

Biosynthesis of Mitochondrial Porin and Insertion into the Outer Mitochondrial Membrane of Neuruspora crassa

Mitochondrial porin, the major protein of the outer mitochondrial membrane is synthesized by free cytoplasmic polysomes. The apparent molecular weight of the porin synthesized in homologous or heterologous cell-free systems is the same as that of the mature porin. Transfer in vitro of mitochondrial porin from the cytosolic fraction into the outer membrane of mitochondria could be demonstrated. Before membrane insertion, mitochondrial porin is highly sensitive to added proteinase; afterwards it is strongly protected. Binding of the precursor form to mitochondria occurs at 4°C and appears to precede insertion into the membrane. Unlike transfer of many precursor proteins into or across the inner mitochondrial membrane, assembly of the porin is not dependent on an electrical potential across the inner membrane