1,103 research outputs found
Association of Exposure to Phthalates with Endometriosis and Uterine Leiomyomata: Findings from NHANES, 1999-2004
BACKGROUND. Phthalates are ubiquitous chemicals used in consumer products. Some phthalates are reproductive toxicants in experimental animals, but human data are limited. OBJECTIVE. We conducted a cross-sectional study of urinary phthalate metabolite concentrations in relation to self-reported history of endometriosis and uterine leiomyomata among 1,227 women 20-54 years of age from three cycles of the National Health and Nutrition Examination Survey (NHANES), 1999-2004. METHODS. We examined four phthalate metabolites: mono(2-ethylhexyl) phthalate (MEHP), monobutyl phthalate (MBP), monoethyl phthalate (MEP), and monobenzyl phthalate (MBzP). From the last two NHANES cycles, we also examined mono(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP) and mono(2-ethyl-5-oxohexyl) phthalate (MEOHP). We used logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (CIs), adjusting for potential confounders. RESULTS. Eighty-seven (7%) and 151 (12%) women reported diagnoses of endometriosis and leiomyomata, respectively. The ORs comparing the highest versus lowest three quartiles of urinary MBP were 1.36 (95% CI, 0.77-2.41) for endometriosis, 1.56 (95% CI, 0.93-2.61) for leiomyomata, and 1.71 (95% CI, 1.07-2.75) for both conditions combined. The corresponding ORs for MEHP were 0.44 (95% CI, 0.19-1.02) for endometriosis, 0.63 (95% CI, 0.35-1.12) for leiomyomata, and 0.59 (95% CI, 0.37-0.95) for both conditions combined. Findings for MEHHP and MEOHP agreed with findings for MEHP with respect to endometriosis only. We observed null associations for MEP and MBzP. Associations were similar when we excluded women diagnosed > 7 years before their NHANES evaluation. CONCLUSION. The positive associations for MBP and inverse associations for MEHP in relation to endometriosis and leiomyomata warrant investigation in prospective studies
Multiplexed, High Density Electrophysiology with Nanofabricated Neural Probes
Extracellular electrode arrays can reveal the neuronal network correlates of behavior with single-cell, single-spike, and sub-millisecond resolution. However, implantable electrodes are inherently invasive, and efforts to scale up the number and density of recording sites must compromise on device size in order to connect the electrodes. Here, we report on silicon-based neural probes employing nanofabricated, high-density electrical leads. Furthermore, we address the challenge of reading out multichannel data with an application-specific integrated circuit (ASIC) performing signal amplification, band-pass filtering, and multiplexing functions. We demonstrate high spatial resolution extracellular measurements with a fully integrated, low noise 64-channel system weighing just 330 mg. The on-chip multiplexers make possible recordings with substantially fewer external wires than the number of input channels. By combining nanofabricated probes with ASICs we have implemented a system for performing large-scale, high-density electrophysiology in small, freely behaving animals that is both minimally invasive and highly scalable
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Weight management during teenage pregnancy: Issues to consider when developing appropriate support
Teenage pregnancy is more prevalent in areas of high obesity, compared to areas where obesity levels are low. Risks associated with maternal obesity in pregnant teenagers include pre-eclampsia and caesarean delivery. To reduce these risks, pregnant teenagers need to be supported to gain a healthy weight in pregnancy. This includes encouraging these women to eat healthily through providing appropriate information including online or smartphone apps in conjunction with face-to-face support. These young women also need encouragement to be physically active. This support must be tailored to the teenage population considering their specific barriers and facilitators to behaviour change. Midwives with the aid of a multidisciplinary team play a key role in encouraging these healthy behaviours
Ezrin interacts with the SARS coronavirus spike protein and restrains infection at the entry stage
© 2012 Millet et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Background: Entry of Severe Acute Respiratory Syndrome coronavirus (SARS-CoV) and its envelope fusion with host cell membrane are controlled by a series of complex molecular mechanisms, largely dependent on the viral envelope glycoprotein Spike (S). There are still many unknowns on the implication of cellular factors that regulate the entry process. Methodology/Principal Findings: We performed a yeast two-hybrid screen using as bait the carboxy-terminal endodomain of S, which faces the cytosol during and after opening of the fusion pore at early stages of the virus life cycle. Here we show that the ezrin membrane-actin linker interacts with S endodomain through the F1 lobe of its FERM domain and that both the eight carboxy-terminal amino-acids and a membrane-proximal cysteine cluster of S endodomain are important for this interaction in vitro. Interestingly, we found that ezrin is present at the site of entry of S-pseudotyped lentiviral particles in Vero E6 cells. Targeting ezrin function by small interfering RNA increased S-mediated entry of pseudotyped particles in epithelial cells. Furthermore, deletion of the eight carboxy-terminal amino acids of S enhanced S-pseudotyped particles infection. Expression of the ezrin dominant negative FERM domain enhanced cell susceptibility to infection by SARS-CoV and S pseudotyped particles and potentiated S-dependent membrane fusion. Conclusions/Significance: Ezrin interacts with SARS-CoV S endodomain and limits virus entry and fusion. Our data present a novel mechanism involving a cellular factor in the regulation of S-dependent early events of infection.This work was supported by the Research Grant Council of Hong Kong (RGC#760208)and the RESPARI project of the International Network of Pasteur Institutes
Imaging the Two Gaps of the High-TC Superconductor Pb-Bi2Sr2CuO6+x
The nature of the pseudogap state, observed above the superconducting
transition temperature TC in many high temperature superconductors, is the
center of much debate. Recently, this discussion has focused on the number of
energy gaps in these materials. Some experiments indicate a single energy gap,
implying that the pseudogap is a precursor state. Others indicate two,
suggesting that it is a competing or coexisting phase. Here we report on
temperature dependent scanning tunneling spectroscopy of Pb-Bi2Sr2CuO6+x. We
have found a new, narrow, homogeneous gap that vanishes near TC, superimposed
on the typically observed, inhomogeneous, broad gap, which is only weakly
temperature dependent. These results not only support the two gap picture, but
also explain previously troubling differences between scanning tunneling
microscopy and other experimental measurements.Comment: 6 page
The Distribution of Dust and Gas in Elliptical Galaxies
Results from IRAS and recent optical CCD surveys are examined to discuss the
distribution and origin of dust and ionized gas in elliptical galaxies. In
strong contrast with the situation among spiral galaxies, masses of dust in
elliptical galaxies as derived from optical extinction are an order of
magnitude LOWER than those derived from IRAS data. I find that this dilemma can
be resolved by assuming the presence of a diffusely distributed component of
dust which is not detectable in optical data.
The morphology of dust lanes and their association with ionized gas in
elliptical galaxies argues for an external origin of BOTH components of the
ISM.Comment: Invited talk given at conference on "NEW EXTRAGALACTIC PERSPECTIVES
IN THE NEW SOUTH AFRICA: Changing Perceptions of the Morphology, Dust Content
and Dust-Gas Ratios in Galaxies", Held in Johannesburg, South Africa, during
January 22-26, 1996. Proceedings will be edited by D.L. Block and published
by Kluwer, Dordrecht, The Netherlands. uuencoded, gzipped LaTeX file of 8
pages; figures included as PostScript files (enclosed). Uses crckapb.sty
(enclosed) and psfig.st
STM imaging of symmetry-breaking structural distortion in the Bi-based cuprate superconductors
A complicating factor in unraveling the theory of high-temperature (high-Tc)
superconductivity is the presence of a "pseudogap" in the density of states,
whose origin has been debated since its discovery [1]. Some believe the
pseudogap is a broken symmetry state distinct from superconductivity [2-4],
while others believe it arises from short-range correlations without symmetry
breaking [5,6]. A number of broken symmetries have been imaged and identified
with the pseudogap state [7,8], but it remains crucial to disentangle any
electronic symmetry breaking from pre-existing structural symmetry of the
crystal. We use scanning tunneling microscopy (STM) to observe an orthorhombic
structural distortion across the cuprate superconducting Bi2Sr2Can-1CunO2n+4+x
(BSCCO) family tree, which breaks two-dimensional inversion symmetry in the
surface BiO layer. Although this inversion symmetry breaking structure can
impact electronic measurements, we show from its insensitivity to temperature,
magnetic field, and doping, that it cannot be the long-sought pseudogap state.
To detect this picometer-scale variation in lattice structure, we have
implemented a new algorithm which will serve as a powerful tool in the search
for broken symmetry electronic states in cuprates, as well as in other
materials.Comment: 4 figure
Cerebral activations related to ballistic, stepwise interrupted and gradually modulated movements in parkinson patients
Patients with Parkinson's disease (PD) experience impaired initiation and inhibition of movements such as difficulty to start/stop walking. At single-joint level this is accompanied by reduced inhibition of antagonist muscle activity. While normal basal ganglia (BG) contributions to motor control include selecting appropriate muscles by inhibiting others, it is unclear how PD-related changes in BG function cause impaired movement initiation and inhibition at single-joint level. To further elucidate these changes we studied 4 right-hand movement tasks with fMRI, by dissociating activations related to abrupt movement initiation, inhibition and gradual movement modulation. Initiation and inhibition were inferred from ballistic and stepwise interrupted movement, respectively, while smooth wrist circumduction enabled the assessment of gradually modulated movement. Task-related activations were compared between PD patients (N = 12) and healthy subjects (N = 18). In healthy subjects, movement initiation was characterized by antero-ventral striatum, substantia nigra (SN) and premotor activations while inhibition was dominated by subthalamic nucleus (STN) and pallidal activations, in line with the known role of these areas in simple movement. Gradual movement mainly involved antero-dorsal putamen and pallidum. Compared to healthy subjects, patients showed reduced striatal/SN and increased pallidal activation for initiation, whereas for inhibition STN activation was reduced and striatal-thalamo-cortical activation increased. For gradual movement patients showed reduced pallidal and increased thalamo-cortical activation. We conclude that PD-related changes during movement initiation fit the (rather static) model of alterations in direct and indirect BG pathways. Reduced STN activation and regional cortical increased activation in PD during inhibition and gradual movement modulation are better explained by a dynamic model that also takes into account enhanced responsiveness to external stimuli in this disease and the effects of hyper-fluctuating cortical inputs to the striatum and STN in particular
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