High prevalence of early repolarization in the paediatric relatives of sudden arrhythmic death syndrome victims and in normal controls

AIMS: Elevation of the ECG J-point in the inferior and lateral leads (early repolarization) has been described in survivors of ventricular fibrillation (VF) arrest and occurs in adult first-degree relatives of sudden cardiac death (SCD) probands at a frequency significantly greater than in controls, raising the possibility that this could represent an independent risk factor in the aetiology of SCD. However, data on early repolarization in the paediatric population are lacking. This study aimed to assess the prevalence of early repolarization in paediatric first-degree relatives of sudden arrhythmic death syndrome (SADS) victims. METHODS AND RESULTS: Paediatric relatives (aged 1 mV from baseline. The ECGs of 77 consecutive paediatric first-degree relatives of SADS victims from 46 families were reviewed by two assessors. J-point elevation was present in 24 patients (31%) of this patient group compared with the reported prevalence of 5–13% in the published general paediatric population (P = 0.02) and that of 19% in the internal control group (P = 0.07). Subgroup analysis according to J-point elevation and ST segment morphologies showed a significantly higher prevalence of inferior early repolarization 0.1–0.2 mV in the study group compared with controls (75 vs. 38%; P = 0.02). CONCLUSION: Inferolateral J-point elevation occurs in a substantial proportion of paediatric first-degree relatives of SADS probands with a similar prevalence to that described in adults. This suggests that early repolarization could be an important inherited trait when evaluating relatives of SADS victims. However, prospective follow-up of this group of children is important to establish the implication of this finding in future risk stratification, given the apparently high prevalence in normal individuals

Calcitization of aragonitic bryozoans in Cenozoic tropical carbonates from East Kalimantan, Indonesia

© The Author(s) 2016. Open Access. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The file attached is the published version of the article

Vascular responses of the extremities to transdermal application of vasoactive agents in Caucasian and African descent individuals

This is an accepted manuscript of an article published by Springer in European Journal of Applied Physiology on 04/04/2015, available online: https://doi.org/10.1007/s00421-015-3164-2 The accepted version of the publication may differ from the final published version.© 2015, Springer-Verlag Berlin Heidelberg. Purpose: Individuals of African descent (AFD) are more susceptible to non-freezing cold injury than Caucasians (CAU) which may be due, in part, to differences in the control of skin blood flow. We investigated the skin blood flow responses to transdermal application of vasoactive agents. Methods: Twenty-four young males (12 CAU and 12 AFD) undertook three tests in which iontophoresis was used to apply acetylcholine (ACh 1 w/v %), sodium nitroprusside (SNP 0.01 w/v %) and noradrenaline (NA 0.5 mM) to the skin. The skin sites tested were: volar forearm, non-glabrous finger and toe, and glabrous finger (pad) and toe (pad). Results: In response to SNP on the forearm, AFD had less vasodilatation for a given current application than CAU (P = 0.027–0.004). ACh evoked less vasodilatation in AFD for a given application current in the non-glabrous finger and toe compared with CAU (P = 0.043–0.014) with a lower maximum vasodilatation in the non-glabrous finger (median [interquartile], AFD n = 11, 41[234] %, CAU n = 12, 351[451] %, P = 0.011) and non-glabrous toe (median [interquartile], AFD n = 9, 116[318] %, CAU n = 12, 484[720] %, P = 0.018). ACh and SNP did not elicit vasodilatation in the glabrous skin sites of either group. There were no ethnic differences in response to NA. Conclusion: AFD have an attenuated endothelium-dependent vasodilatation in non-glabrous sites of the fingers and toes compared with CAU. This may contribute to lower skin temperature following cold exposure and the increased risk of cold injuries experienced by AFD.Published versio

Road to evolution? Local adaptation to road adjacency in an amphibian (Ambystoma maculatum)

The network of roads on the landscape is vast, and contributes a suite of negative ecological effects on adjacent habitats, ranging from fragmentation to contamination by runoff. In addition to the immediate consequences faced by biota living in roaded landscapes, road effects may further function as novel agents of selection, setting the stage for contemporary evolutionary changes in local populations. Though the ecological consequences of roads are well described, evolutionary outcomes remain largely unevaluated. To address these potential responses in tandem, I conducted a reciprocal transplant experiment on early life history stages of a pool-breeding salamander. My data show that despite a strong, negative effect of roadside pools on salamander performance, populations adjacent to roads are locally adapted. This suggests that the response of species to human-altered environments varies across local populations, and that adaptive processes may mediate this response

Relaxation of Adaptive Evolution during the HIV-1 Infection Owing to Reduction of CD4+ T Cell Counts

Background: the first stages of HIV-1 infection are essential to establish the diversity of virus population within host. It has been suggested that adaptation to host cells and antibody evasion are the leading forces driving HIV evolution at the initial stages of AIDS infection. in order to gain more insights on adaptive HIV-1 evolution, the genetic diversity was evaluated during the infection time in individuals contaminated by the same viral source in an epidemic cluster. Multiple sequences of V3 loop region of the HIV-1 were serially sampled from four individuals: comprising a single blood donor, two blood recipients, and another sexually infected by one of the blood recipients. the diversity of the viral population within each host was analyzed independently in distinct time points during HIV-1 infection.Results: Phylogenetic analysis identified multiple HIV-1 variants transmitted through blood transfusion but the establishing of new infections was initiated by a limited number of viruses. Positive selection (d(N)/d(S)>1) was detected in the viruses within each host in all time points. in the intra-host viruses of the blood donor and of one blood recipient, X4 variants appeared respectively in 1993 and 1989. in both patients X4 variants never reached high frequencies during infection time. the recipient, who X4 variants appeared, developed AIDS but kept narrow and constant immune response against HIV-1 during the infection time.Conclusion: Slowing rates of adaptive evolution and increasing diversity in HIV-1 are consequences of the CD4+ T cells depletion. the dynamic of R5 to X4 shift is not associated with the initial amplitude of humoral immune response or intensity of positive selection.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fed Univ Para, Inst Biotechnol, BR-66059 Belem, Para, BrazilUniv São Paulo, Inst Trop Med, São Paulo, SP, BrazilCDC, Ctr Dis Control & Prevent, Branch Lab, Atlanta, GA 30333 USAUniv Calif San Francisco, Dept Lab Med, San Francisco, CA 94143 USABlood Syst Res Inst, San Francisco, CA USABlood Syst Inc, San Francisco, CA USAUniversidade Federal de São Paulo, São Paulo, BrazilUniversidade Federal de São Paulo, São Paulo, BrazilFAPESP: 07/52841-8Web of Scienc

High-temperature performance of ferritic steels in fireside corrosion regimes: temperature and deposits

The paper reports high temperature resistance of ferritic steels in fireside corrosion regime in terms of temperature and deposits aggressiveness. Four candidate power plant steels: 15Mo3, T22, T23 and T91 were exposed under simulated air-fired combustion environment for 1000 h. The tests were conducted at 600, 650 and 700 °C according to deposit-recoat test method. Post-exposed samples were examined via dimensional metrology (the main route to quantify metal loss), and mass change data were recorded to perform the study of kinetic behavior at elevated temperatures. Microstructural investigations using ESEM-EDX were performed in order to investigate corrosion degradation and thickness of the scales. The ranking of the steels from most to the least damage was 15Mo3 > T22 > T23 > T91 in all three temperatures. The highest rate of corrosion in all temperatures occurred under the screening deposit

Is Mn-Bound Substrate Water Protonated in the S2 State of Photosystem II?

In spite of great progress in resolving the geometric structure of the water-splitting Mn4OxCa cluster in photosystem II, the binding sites and modes of the two substrate water molecules are still insufficiently characterized. While time-resolved membrane-inlet mass spectrometry measurements indicate that both substrate water molecules are bound to the oxygen-evolving complex (OEC) in the S2 and S3 states (Hendry and Wydrzynski in Biochemistry 41:13328–13334, 2002), it is not known (1) if they are both Mn-bound, (2) if they are terminal or bridging ligands, and (3) in what protonation state they are bound in the different oxidation states Si (i = 0, 1, 2, 3, 4) of the OEC. By employing 17O hyperfine sublevel correlation (HYSCORE) spectroscopy we recently demonstrated that in the S2 state there is only one (type of) Mn-bound oxygen that is water exchangeable. We therefore tentatively identified this oxygen as one substrate ‘water’ molecule, and on the basis of the finding that it has a hyperfine interaction of about 10 MHz with the electron spin of the Mn4OxCa cluster, we suggest that it is bound as a Mn–O–Mn bridge within a bis-μ2 oxo-bridged unit (Su et al. in J Am Chem Soc 130:786–787, 2008). Employing pulse electron paramagnetic resonance, 1H/2H Mims electron-nuclear double resonance and 2H-HYSCORE spectroscopies together with 1H/2H-exchange here, we test this hypothesis by probing the protonation state of this exchangeable oxygen. We conclude that this oxygen is fully deprotonated. This result is discussed in the light of earlier reports in the literature

Gene Expression Profiles Distinguish the Carcinogenic Effects of Aristolochic Acid in Target (Kidney) and Non-target (Liver) Tissues in Rats

BACKGROUND: Aristolochic acid (AA) is the active component of herbal drugs derived from Aristolochia species that have been used for medicinal purposes since antiquity. AA, however, induced nephropathy and urothelial cancer in people and malignant tumors in the kidney and urinary tract of rodents. Although AA is bioactivated in both kidney and liver, it only induces tumors in kidney. To evaluate whether microarray analysis can be used for distinguishing the tissue-specific carcinogenicity of AA, we examined gene expression profiles in kidney and liver of rats treated with carcinogenic doses of AA. RESULTS: Microarray analysis was performed using the Rat Genome Survey Microarray and data analysis was carried out within ArrayTrack software. Principal components analysis and hierarchical cluster analysis of the expression profiles showed that samples were grouped together according to the tissues and treatments. The gene expression profiles were significantly altered by AA treatment in both kidney and liver (p < 0.01; fold change > 1.5). Functional analysis with Ingenuity Pathways Analysis showed that there were many more significantly altered genes involved in cancer-related pathways in kidney than in liver. Also, analysis with Gene Ontology for Functional Analysis (GOFFA) software indicated that the biological processes related to defense response, apoptosis and immune response were significantly altered by AA exposure in kidney, but not in liver. CONCLUSION: Our results suggest that microarray analysis is a useful tool for detecting AA exposure; that analysis of the gene expression profiles can define the differential responses to toxicity and carcinogenicity of AA from kidney and liver; and that significant alteration of genes associated with defense response, apoptosis and immune response in kidney, but not in liver, may be responsible for the tissue-specific toxicity and carcinogenicity of AA