Left ventricular concentric remodelling and extracardiac target organ damage in essential hypertension

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Short-term reproducibility of nocturnal non-dipping pattern in recently diagnosed essential hypertensives.

Objective: To investigate in a selected population of patients with a recently diagnosed essential hypertension the short-term intrasubject variability of diurnal changes in blood pressure (BP). Methods: Two hundred and eight consecutive, recently diagnosed, never treated essential hypertensives (119 men, 89 women, 46 ± 12 years) underwent 24-h ambulatory BP monitoring (ABPM) twice within 3 weeks. Dipping pattern was defined as a reduction in average systolic and diastolic BP at night greater than 10% compared to average daytime values. Results: 177 subjects (85%) showed no change in their diurnal variations in BP. Of the 159 subjects who had a dipping pattern on first ABPM, 134 (90.6%) confirmed this type of profile on the second ABPM, while 15 (9.4%) showed a non-dipping pattern. Of the 59 subjects who had a non-dipping pattern on the first ABPM, 43 (72.2%) confirmed their initial profile on the second ABPM, while 16 (28.8%) did not. Conclusion: These findings indicate that short-term reproducibility of diurnal changes in BP in early phases of untreated essential hypertension, characterized by a large prevalence of dipping pattern, is overall satisfactory. However, our study underlines that also in this particularly selected population of hypertensives the definition of non-dipping status on the basis of a single ABPM remains unreliable in about one-third of patients

Regional Selection Acting on the OFD1 Gene Family

The OFD1 (oral-facial-digital, type 1) gene is implicated in several developmental disorders in humans. The X-linked OFD1 (OFD1X) is conserved in Eutheria. Knowledge about the Y-linked paralog (OFD1Y) is limited. In this study, we identified an OFD1Y on the bovine Y chromosome, which is expressed differentially from the bovine OFD1X. Phylogenetic analysis indicated that: a) the eutherian OFD1X and OFD1Y were derived from the pair of ancestral autosomes during sex chromosome evolution; b) the autosomal OFD1 pseudogenes, present in Catarrhini and Murinae, were derived from retropositions of OFD1X after the divergence of primates and rodents; and c) the presence of OFD1Y in the ampliconic region of the primate Y chromosome is an indication that the expansion of the ampliconic region may initiate from the X-degenerated sequence. In addition, we found that different regions of OFD1/OFD1X/OFD1Y are under differential selection pressures. The C-terminal half of OFD1 is under relaxed selection with an elevated Ka/Ks ratio and clustered positively selected sites, whereas the N-terminal half is under stronger constraints. This study provides some insights into why the OFD1X gene causes OFD1 (male-lethal X-linked dominant) and SGBS2 & JSRDs (X-linked recessive) syndromes in humans, and reveals the origin and evolution of the OFD1 family, which will facilitate further clinical investigation of the OFD1-related syndromes

Effect of eluent composition and pH and chemiluminescent reagent pH on ion chromatographic selectivity and luminol-based chemiluminescence detection of Co2+, Mn2+ and Fe2+ at trace levels

The alkaline-luminol/H2O2-based chemiluminescent (CL) detection of Fe2+, Co2+, andMn2+, separated with a Dionex CS5A ion chromatographic phase was studied by means of a multi-pump flow system allowing the variation of the post-column solution composition. A perchlorate gradient at pH 1.9 (with HCl) was used to separate cations partially complexed with 5.6mM oxalate present in the eluent and necessary for the chosen separation phase. A 0.91mM luminol, 3.3mM H2O2 in 0.25M carbonate buffer at pH 10.5 composition was chosen as CL reagent solution. The chosen pH value warrants signal repeatability and wider linearity range although absolute signal is not maximum. The CL signal was related to the pH of the two post-column mixing solutions. Calibration plots of Co2+ and Fe2+ were linear in the chosen concentration range whilst a parabolic model was the best fit for Mn2+. Detection limits were 0.24, 0.50 and 375nM for Co2+, Fe2+ and Mn2+, respectively. The method was used to determine Co2+ at trace level in commercial copper chelates used for animal feeding. A comparison with a chromatographic method with spectrophotometric detection was made giving results comparable both in absolute values and accuracy

A pH-stat study of the reaction of some transition metal cations with disodium ethylenedinitrilotetraacetate (EDTA) and its analytical application

The pH-stat titration technique is an autonomous and very powerful tool for performing and monitoring chelatometric titrations of metal cations with great accuracy, poorly known, however, and seldom exploited. Based on measurement of the amount of strong base required to keep the pH of the test solution at a selected value during stepwise known additions of ethylenedinitrilotetraacetate (EDTA), it requires a glass electrode as the only sensor and is easily implemented on potentiometric titrators. It was introduced a quarter of century ago on an empirical basis for a very peculiar purpose (determination of calcium in diary products), but only very recently it was generalised and its fundamentals were thoroughly examined. In this work, pH-static titrations of some transition metal cations of analytical relevance (Co2(+), Cu2+, Mn2+, Zn2+) were thoroughly investigated in the acid pH range between 2.3 and 5 or 7 (the highest pH depending on the metal hydroxide or carbonate solubility). The results at higher acidity showed unsuspected properties of such chelation reactions. At moderately acid pH (generally >= 4), indeed, pH-static titrations yield results of high precision and accuracy. On decreasing pH, however, the reaction stoichiomety deviates more and more from the 1:1 ratio between chelating agent and cation, seemingly because of formation of binuclear complexes, an occurrence very seldom mentioned in the current literature. The optimal titration conditions for each metal are defined, and directions for establishing a laboratory protocol for quantitative determinations are given. (c) 2006 Elsevier B.V All rights reserved

An order-adaptive compact approximation Taylor method for systems of conservation laws

We present a new family of high-order shock-capturing finite difference numerical methods for systems of conservation laws. These methods, called Adaptive Compact Approximation Taylor (ACAT) schemes, use centered (2p+1)-point stencils, where p may take values in {1,2,…,P} according to a new family of smoothness indicators in the stencils. The methods are based on a combination of a robust first order scheme and the Compact Approximate Taylor (CAT) methods of order 2p-order, p=1,2,…,P so that they are first order accurate near discontinuities and have order 2p in smooth regions, where (2p+1) is the size of the biggest stencil in which large gradients are not detected. CAT methods, introduced in [3], are an extension to nonlinear problems of the Lax-Wendroff methods in which the Cauchy-Kovalesky (CK) procedure is circumvented following the strategy introduced in [22] that allows one to compute time derivatives in a recursive way using high-order centered differentiation formulas combined with Taylor expansions in time. The expression of ACAT methods for 1D and 2D systems of conservative laws is given and the performance is checked in a number of test cases for several linear and nonlinear systems of conservation laws, including Euler equations for gas dynamics