Associative connection of infectious and inflammatory diseases in pregnancy and severe preeclampsia

Materials and methods. This retrospective case-control study enrolled 50 women with severe preeclampsia and 50 control women with spontaneous singleton pregnancy. Median age of women ranged from 20 to 35 years. All women did not have a history of hypertension, autoimmune, metabolic, renal, or cardiac diseases, and preeclampsia before this pregnancy. We have analyzed χ2, odds ratio (OR) and its 95% confidence intervals (95% Cl). Results. We found significant association between maternal systemic infectious and severe preeclampsia (OR = 49.6; 95% Cl 13.05-188.64). The risk of severe preeclampsia were significantly lower in patients with local infections of the lower genital tract (OR = 4.5; 95% Cl 1.49-6.71). Asymptomatic bacteriuria is associated with the highest risk of severe preeclampsia (OR = 17.0; 95% Cl 4.66-61.81). Acute gravidarum pyelonephritis showed lower association with severe preeclampsia (OR = 5.4; 95% Cl 1.69-10.54). We did not observe increased risk of severe preeclampsia with acute respiratory infections (OR = 2.0; 95% Cl 0.71-4.69). Acute non-specific bacterial vaginitis and acute candidiasis vulvovaginitis were found to be risk factors of severe preeclampsia (OR = 6.7; 95% Cl 1.90-11.02 and OR = 4.3; 95% Cl 1.45-9.99 respectively). Cytomegalovirus infection (2 %), toxoplasmosis (2 %), Chlamydia trachomatis cervicitis (4 %), acute Trichomonas colpitis (2 %) and bacterial vaginosis (4 %) were found only in patients with severe preeclampsia. Conclusion. Our data support that acute maternal infection is associated with an increased risk of severe preeclampsia in healthy women with singleton pregnancy. Systemic inflammatory response might be the main potential mechanisms related to infections and enhanced development of severe preeclampsia. Further research is required to elucidate the underlying mechanism of this association

Donor states in modulation-doped Si/SiGe heterostructures

We present a unified approach for calculating the properties of shallow donors inside or outside heterostructure quantum wells. The method allows us to obtain not only the binding energies of all localized states of any symmetry, but also the energy width of the resonant states which may appear when a localized state becomes degenerate with the continuous quantum well subbands. The approach is non-variational, and we are therefore also able to evaluate the wave functions. This is used to calculate the optical absorption spectrum, which is strongly non-isotropic due to the selection rules. The results obtained from calculations for Si/Si$_{1-x}$Ge$_x$ quantum wells allow us to present the general behavior of the impurity states, as the donor position is varied from the center of the well to deep inside the barrier. The influence on the donor ground state from both the central-cell effect and the strain arising from the lattice mismatch is carefully considered.Comment: 17 pages, 10 figure

Mass spectrometric simultaneous quantification of tau species in plasma shows differential associations with amyloid and tau pathologies

Blood phosphorylated tau (p-tau) biomarkers, at differing sites, demonstrate high accuracy to detect Alzheimerʼs disease (AD). However, knowledge on the optimal marker for disease identification across the AD continuum and the link to pathology is limited. This is partly due to heterogeneity in analytical methods. In this study, we employed an immunoprecipitation mass spectrometry method to simultaneously quantify six phosphorylated (p-tau181, p-tau199, p-tau202, p-tau205, p-tau217 and p-tau231) and two non-phosphorylated plasma tau peptides in a total of 214 participants from the Paris Lariboisière and Translational Biomarkers of Aging and Dementia cohorts. Our results indicate that p-tau217, p-tau231 and p-tau205 are the plasma tau forms that best reflect AD-related brain changes, although with distinct emergences along the disease course and correlations with AD features—amyloid and tau. These findings support the differential association of blood p-tau variants with AD pathology, and our method offers a potential tool for disease staging in clinical trials

Energy spectra of fractional quantum Hall systems in the presence of a valence hole

The energy spectrum of a two-dimensional electron gas (2DEG) in the fractional quantum Hall regime interacting with an optically injected valence band hole is studied as a function of the filling factor $\nu$ and the separation $d$ between the electron and hole layers. The response of the 2DEG to the hole changes abruptly at $d$ of the order of the magnetic length $\lambda$. At $d<\lambda$, the hole binds electrons to form neutral ($X$) or charged ($X^-$) excitons, and the photoluminescence (PL) spectrum probes the lifetimes and binding energies of these states rather than the original correlations of the 2DEG. The ``dressed exciton'' picture (in which the interaction between an exciton and the 2DEG was proposed to merely enhance the exciton mass) is questioned. Instead, the low energy states are explained in terms of Laughlin correlations between the constituent fermions (electrons and $X^-$'s) and the formation of two-component incompressible fluid states in the electron--hole plasma. At $d>2\lambda$, the hole binds up to two Laughlin quasielectrons (QE) of the 2DEG to form fractionally charged excitons $h$QE$_n$. The previously found ``anyon exciton'' $h$QE$_3$ is shown to be unstable at any value of $d$. The critical dependence of the stability of different $h$QE$_n$ complexes on the presence of QE's in the 2DEG leads to the observed discontinuity of the PL spectrum at $\nu={1\over3}$ or ${2\over3}$.Comment: 16 pages, 14 figures, submitted to PR

Electron transport through double quantum dots

Electron transport experiments on two lateral quantum dots coupled in series are reviewed. An introduction to the charge stability diagram is given in terms of the electrochemical potentials of both dots. Resonant tunneling experiments show that the double dot geometry allows for an accurate determination of the intrinsic lifetime of discrete energy states in quantum dots. The evolution of discrete energy levels in magnetic field is studied. The resolution allows to resolve avoided crossings in the spectrum of a quantum dot. With microwave spectroscopy it is possible to probe the transition from ionic bonding (for weak inter-dot tunnel coupling) to covalent bonding (for strong inter-dot tunnel coupling) in a double dot artificial molecule. This review on the present experimental status of double quantum dot studies is motivated by their relevance for realizing solid state quantum bits.Comment: 32 pages, 31 figure

Cytisus scoparius link - A natural antioxidant

BACKGROUND: Recent investigations have shown that the antioxidant properties of plants could be correlated with oxidative stress defense and different human diseases. In this respect flavonoids and other polyphenolic compounds have gained the greatest attention. The plant Cytisus scoparius contains the main constituent of flavone and flavonals. The present study was undertaken to evaluate the in vitro antioxidant activities of extract of aerial part of Cytisus scoparius. METHODS: The plant extract was tested for DPPH (1, 1-diphenyl, 2-picryl hydrazyl) radical scavenging, nitric oxide radical scavenging, superoxide anion radical scavenging, hydroxyl radical scavenging, antilipid peroxidation assay, reducing power and total phenol content. RESULTS: The extract exhibited scavenging potential with IC(50 )value of 1.5 μg/ml, 116.0 μg/ml and 4.7 μg/ml for DPPH, nitric oxide and superoxide anion radicals. The values were found to lesser than those of vitamin C, rutin, and curcumin, as standards. The extract showed 50% protection at the dose of 104.0 μg/ml in lipid peroxidation induced by Fe(2+)/ ascorbate system in rat liver microsomal preparation. There is decrease in hydroxyl radical generation with IC(50 )value of 27.0 μg/ml when compared with standard vitamin E. The reducing power of the extract depends on the amount of extract. A significant amount of polyphenols could be detected by the equivalent to 0.0589 μg of pyrocatechol from 1 mg of extract. CONCLUSION: The results obtained in the present study indicate that hydro alcoholic extract of aerial part of Cytisus scoparius is a potential source of natural antioxidants

Viral to metazoan marine plankton nucleotide sequences from the Tara Oceans expedition

A unique collection of oceanic samples was gathered by the Tara Oceans expeditions (2009-2013), targeting plankton organisms ranging from viruses to metazoans, and providing rich environmental context measurements. Thanks to recent advances in the field of genomics, extensive sequencing has been performed for a deep genomic analysis of this huge collection of samples. A strategy based on different approaches, such as metabarcoding, metagenomics, single-cell genomics and metatranscriptomics, has been chosen for analysis of size-fractionated plankton communities. Here, we provide detailed procedures applied for genomic data generation, from nucleic acids extraction to sequence production, and we describe registries of genomics datasets available at the European Nucleotide Archive (ENA, www.ebi.ac.uk/ena). The association of these metadata to the experimental procedures applied for their generation will help the scientific community to access these data and facilitate their analysis. This paper complements other efforts to provide a full description of experiments and open science resources generated from the Tara Oceans project, further extending their value for the study of the world's planktonic ecosystems

Unbound states in quantum heterostructures

We report in this review on the electronic continuum states of semiconductor Quantum Wells and Quantum Dots and highlight the decisive part played by the virtual bound states in the optical properties of these structures. The two particles continuum states of Quantum Dots control the decoherence of the excited electron – hole states. The part played by Auger scattering in Quantum Dots is also discussed

Biological features on epibiosis of Amphibalanus improvisus (Cirripedia) on Macrobrachium acanthurus (Decapoda)

This study aimed to describe the epibiosis of barnacles Amphibalanus improvisus on eight adult Macrobrachium acanthurus males from the Mundaú Lagoon, state of Alagoas, Brazil. The number of epibiont barnacles varied from 247 to 1,544 specimens per prawn; these were distributed predominantly on the cephalothorax and pereiopods, but also on the abdomen and other appendices. Although some were already reproducing, most barnacles had been recruited recently or were still sexually immature; this suggests recent host arrival in that estuarine environment. Despite the fact that other barnacles occur in this region, A. improvisus is the only species reported as an epibiont on Macrobrachium acanthurus; this was also the first record of epibiosis on this host. The occurrence of innumerable specimens in the pereiopods' articulations and the almost complete covering of the carapace of some prawns (which also increased their weight) suggest that A. improvisus is adapted to fixate this kind of biogenic substrate and that the relationship between the two species biologically damages the basibiont.O objetivo deste trabalho foi relatar a epibiose de cirrípedes Amphibalanus improvisus em oito camarões machos adultos da espécie Macrobrachium acanthurus provenientes da Laguna Mundaú, Alagoas, Brasil. O número de cirrípedes epibiontes variou desde 247 até 1.544 espécimes por camarão, distribuídos predominantemente no cefalotórax e pereiópodos, mas presentes também no abdome e demais apêndices. A grande maioria dos cirrípedes era recém-recrutada ou ainda estava sexualmente imatura, embora de alguns estivessem já em reprodução, sugerindo a chegada recente de seu hospedeiro no ambiente estuarino. Apesar de ocorrem outros cirrípedes na região, A. improvisus foi à única espécie relatada como epibionte em Macrobrachium acanthurus e isto se constituiu o primeiro registro de epibiose de Amphibalanus improvisus A ocorrência de inúmeros espécimes nas articulações dos pereiópodos e o recobrimento quase total da carapaça de alguns camarões (incrementando peso aos mesmos) indicam que a espécie epibionte está adaptada à fixação neste substrato biogênico e que a relação entre estas duas espécies traz prejuízos biológicos ao basibionte