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We study the tomographic clustering properties of the photometric cluster catalogue derived from the third data release of the Kilo Degree Survey (KiDS), focusing on the angular correlation function and its spherical harmonic counterpart: the angular power spectrum. We measured the angular correlation function and power spectrum from a sample of 5162 clusters, with an intrinsic richness of λ* ≥ 15, in the photometric redshift range of z ∈ [0.1, 0.6]. We compared our measurements with theoretical models, within the framework of the Λ cold dark matter cosmology. We performed a Markov chain Monte Carlo (MCMC) analysis to constrain the cosmological parameters, Ωm and σ8, as well as the structure growth parameter, S8 ≡ σ8√Ωm/0.3. We adopted Gaussian priors on the parameters of the mass-richness relation, based on the posterior distributions derived from a previous joint analysis of cluster counts and weak-lensing mass measurements carried out on the basis of the same catalogue. From the angular correlation function, we obtained Ωm = 0.32−0.04+0.05, σ8 = 0.77−0.09+0.13, and S8 = 0.80−0.06+0.08, which are in agreement, within 1σ, with the 3D clustering result based on the same cluster sample and with existing complementary studies on other data sets. For the angular power spectrum, we checked the validity of the Poissonian shot noise approximation, also considering the mode-mode coupling induced by the mask. We derived statistically consistent results, in particular, Ωm = 0.24−0.04+0.05 and S8 = 0.93−0.12+0.11; while the constraint on σ8 alone is weaker with respect to the one provided by the angular correlation function, σ8 = 1.01−0.17+0.25. Our results show that the 2D clustering from photometric cluster surveys can provide competitive cosmological constraints with respect to the full 3D clustering statistics. We also demonstrate that they can be successfully applied to ongoing and forthcoming spectrometric and photometric surveys. [ABSTRACT FROM AUTHOR]

Nucleophosmin 1 (NPM1) is an abundant phosphoprotein mainly located in the nucleolus but also shuttling between the nucleus and cytoplasm. NPM1 has been proposed to be involved in synthesis and processing of ribosomal RNA, regulation of chromatin structure and transport of rRNA and ribosomal proteins. NPM1 gene is considered to be implicated in human cancer as it is a frequent target of genetic alterations, primarily in haematopoietic neoplasms. We describe a case of a therapy-responder acute myeloid leukaemia (AML) patient bearing two novel NPM1 mutations. Cells' transfection studies indicate that the presence of one of these mutations is associated to an abnormal nucleolar structure, suggesting that NPM1 may contribute to the control of nucleolar integrity. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This study analyzes the relationship between the function of femoral regions in the rat and the extent of collagen type I posttranslational modifications, to assess whether the different functional roles, i.e., mechanical or metabolic, of the bone tissues are related to the molecular structure of the matrix. For this purpose, 18 female, 100-day-old Sprague-Dawley rats were sacrificed, under anesthesia, and their femurs were removed and dissected free of adhering tissue. The spongy bone of the proximal metaphysis and the diaphysis were then selected as regions exerting prevalently a mechanical function, and the spongy bone of the distal metaphysis was selected as mainly related to metabolic function. Bone prepared from these regions was used to extract and purify the major component of the matrix, type I collagen. The content of hydroxyproline, hydroxylysine, glycosylated hydroxylysine, and pyridinium crosslinks was evaluated and the amount of each compound was expressed as a molar ratio to hydroxyproline. The amount of glycosylated hydroxylysine and pyridinium crosslinks in the distal metaphysis are significantly different from the amounts measured both in the diaphysis and the proximal metaphysis. On the contrary, the amounts of the same compounds in the diaphysis and the proximal metaphysis are statistically the same. The amount of free hydroxylysine, however, appears to be different in the proximal metaphysis and in the diaphysis. The conclusion is that matrix composition differs among different skeletal regions according to the main function they exert. [ABSTRACT FROM AUTHOR]

In Dicentrarchus labrax (the sea bass) the differentiation of lateral muscle fibres occurs at different stages and in different ways in the superficial (red), intermediate (pink) and deep (white) regions of the myotome. At hatching the myotomes are composed of presumptive white and red fibres, the latter forming a superficial monolayer present only near the transverse septum. At this stage, differences between the fibre types are mainly ultrastructural. From their different reactions with isoform-specific antibodies to mullet myosin, and the appearance of histochemical mATPase activity, it appears that in both red and white muscle fibres there is a transition in myosin composition from an early larval form (L1R and L1W respectively) to a late larval form (L2R and L2W) and then to the isoforms typical of adult red and white muscle. The transition from L1W to L2W in the deep muscle occurs very rapidly and early in larval life (between 10 and 28 days), whereas the equivalent transition in the superficial muscle (from L1R to L2R) is a gradual process beginning in fibres near the trasverse septum and spreading hypo- and epi-axially as this layer grows around the deep muscle. The definitive adult forms (AR and AW), distinguishable by the appearance of characteristic histochemical myosin ATPase activity, are present in the superficial red muscle by 80 days, but later in the deep white muscle (by 20 months), respectively. Compared to the superficial red and deep white muscle, the intermediate (pink) muscle layer first appears relatively late (80 days), but then acquires the histo- and immunohistochemical profile characteristic of the adult form much more rapidly. The mosaic appearance of the deep white muscle is first seen during larval life. However, at this stage the smaller fibres of the mosaic have a different histo- and immunohistochemical profile from that seen in the adult small white fibres, which may indicate different mechanisms of histogenesis of new fibres in the deep muscle layer in the early and adult stages. [ABSTRACT FROM AUTHOR]

This study sought to evaluate whether the architecture of the matrix of cortical and trabecular bone is exactly the same. For this purpose we analyzed the extent of some posttranslational modifications of type I collagen, which is the major component of bone matrix. Ten female and 10 male 100-day-old rats were sacrificed and the content of hydroxylysine, glycosylated hydroxylysine, and pyridinium cross-links of collagen from cortical and trabecular bone was determined. The amount of each compound was expressed as a molar ratio with hydroxyproline. The collagen posttranslational modification pattern appears to be the same in both sexes but with a higher extent of differences in females compared with males. Comparing cortical and trabecular bone, the former contains a higher amount of hydroxylysine residues whereas in the latter, glycosylation of hydroxylysine is higher and pyridinium cross-link concentration is lower. Moreover, an inverse linear relationship between glycosylated hydroxylysine and pyridinium cross-links concentration was established, both for female (r = -0.455, P = 0.04) and male rats (r = -0.426; P = 0.06). This paper discusses what these findings may mean in functional terms. [ABSTRACT FROM AUTHOR]

This study evaluated whether pyridinium cross-links, which are positively charged, besides renal clearance are also cleared by the liver into bile. In 13 human bile samples tested, we were able to detect both pyridinoline (PYD) and deoxypyridinoline (DPD) in small amounts which were estimated to be about 1-2% of the amount usually found in urine. To further evaluate the amount of pyridinium cross-links excreted through bile, we studied the stability of these compounds at the alkaline pH of bile. No effect on their stability was detected over a 6-hour incubation. The origin of these molecules in bile and the significance of this finding in the use of PYD and DPD as bone resorption markers are discussed. [ABSTRACT FROM AUTHOR]

The pink muscle of several Teleosts was examined immunohistochemically using antisera specific for the myosins of red and white muscle, and histochemically using various methods for demonstrating myosin ATPase (in ATPase) activity. In the catfish the pink muscle consists of 2 different layers of fibres. The superficial layer has a low mATPase activity after both acid and alkali pre-incubation, whereas the deeper layer has a high mATPase activity after acid and alkali pre-incubation, being more resistent to these conditions even than is the white muscle. In the trout the pink muscle is composed of fibres with the same mATPase activity as in the superficial pink muscle of the catfish, whereas in the rock goby, goldfish, mullet and guppy the pink muscle is like the deep pink layer of the catfish. Immunohistochemically the fibres of the pink muscle behave like the white muscle fibres except in the guppy and rock goby in which at the level of the lateral line there occurs a transition zone between red and pink fibres. The fibres of this region react with both anti-fast and (to a lesser extent) anti-slow myosin antisera, and have a mATPase activity which, going from the superficial to the deeper fibres, gradually loses the red muscle characteristics to acquire those of the main pink muscle layer. [ABSTRACT FROM AUTHOR]