755 research outputs found
Use of flucinolone acetonide for patients with diabetic macular oedema:patient selection criteria and early outcomes in real world setting
Introduction: Fluocinolone acetonide slow release implant (Iluvien®) was approved in December 2013 in UK for treatment of eyes which are pseudophakic with DMO that is unresponsive to other available therapies. This approval was based on evidence from FAME trials which were conducted at a time when ranibizumab was not available. There is a paucity of data on implementation of guidance on selecting patients for this treatment modality and also on the real world outcome of fluocinolone therapy especially in those patients that have been unresponsive to ranibizumab therapy. Method: Retrospective study of consecutive patients treated with fluocinolone between January and August 2014 at three sites were included to evaluate selection criteria used, baseline characteristics and clinical outcomes at 3-month time point. Results: Twenty two pseudophakic eyes of 22 consecutive patients were included. Majority of patients had prior therapy with multiple intravitreal anti-VEGF injections. Four eyes had controlled glaucoma. At baseline mean VA and CRT were 50.7 letters and 631 μm respectively. After 3 months, 18 patients had improved CRT of which 15 of them also had improved VA. No adverse effects were noted. One additional patient required IOP lowering medication. Despite being unresponsive to multiple prior therapies including laser and anti-VEGF injections, switching to fluocinolone achieved treatment benefit. Conclusion: The patient level selection criteria proposed by NICE guidance on fluocinolone appeared to be implemented. This data from this study provides new evidence on early outcomes following fluocinolone therapy in eyes with DMO which had not responded to laser and other intravitreal agents
Suv4-20h Histone Methyltransferases Promote Neuroectodermal Differentiation by Silencing the Pluripotency-Associated Oct-25 Gene
Post-translational modifications (PTMs) of histones exert fundamental roles in regulating gene expression. During development, groups of PTMs are constrained by unknown mechanisms into combinatorial patterns, which facilitate transitions from uncommitted embryonic cells into differentiated somatic cell lineages. Repressive histone modifications such as H3K9me3 or H3K27me3 have been investigated in detail, but the role of H4K20me3 in development is currently unknown. Here we show that Xenopus laevis Suv4-20h1 and h2 histone methyltransferases (HMTases) are essential for induction and differentiation of the neuroectoderm. Morpholino-mediated knockdown of the two HMTases leads to a selective and specific downregulation of genes controlling neural induction, thereby effectively blocking differentiation of the neuroectoderm. Global transcriptome analysis supports the notion that these effects arise from the transcriptional deregulation of specific genes rather than widespread, pleiotropic effects. Interestingly, morphant embryos fail to repress the Oct4-related Xenopus gene Oct-25. We validate Oct-25 as a direct target of xSu4-20h enzyme mediated gene repression, showing by chromatin immunoprecipitaton that it is decorated with the H4K20me3 mark downstream of the promoter in normal, but not in double-morphant, embryos. Since knockdown of Oct-25 protein significantly rescues the neural differentiation defect in xSuv4-20h double-morphant embryos, we conclude that the epistatic relationship between Suv4-20h enzymes and Oct-25 controls the transit from pluripotent to differentiation-competent neural cells. Consistent with these results in Xenopus, murine Suv4-20h1/h2 double-knockout embryonic stem (DKO ES) cells exhibit increased Oct4 protein levels before and during EB formation, and reveal a compromised and biased capacity for in vitro differentiation, when compared to normal ES cells. Together, these results suggest a regulatory mechanism, conserved between amphibians and mammals, in which H4K20me3-dependent restriction of specific POU-V genes directs cell fate decisions, when embryonic cells exit the pluripotent state
Thermodynamic analysis of black hole solutions in gravitating nonlinear electrodynamics
We perform a general study of the thermodynamic properties of static
electrically charged black hole solutions of nonlinear electrodynamics
minimally coupled to gravitation in three space dimensions. The Lagrangian
densities governing the dynamics of these models in flat space are defined as
arbitrary functions of the gauge field invariants, constrained by some
requirements for physical admissibility. The exhaustive classification of these
theories in flat space, in terms of the behaviour of the Lagrangian densities
in vacuum and on the boundary of their domain of definition, defines twelve
families of admissible models. When these models are coupled to gravity, the
flat space classification leads to a complete characterization of the
associated sets of gravitating electrostatic spherically symmetric solutions by
their central and asymptotic behaviours. We focus on nine of these families,
which support asymptotically Schwarzschild-like black hole configurations, for
which the thermodynamic analysis is possible and pertinent. In this way, the
thermodynamic laws are extended to the sets of black hole solutions of these
families, for which the generic behaviours of the relevant state variables are
classified and thoroughly analyzed in terms of the aforementioned boundary
properties of the Lagrangians. Moreover, we find universal scaling laws (which
hold and are the same for all the black hole solutions of models belonging to
any of the nine families) running the thermodynamic variables with the electric
charge and the horizon radius. These scale transformations form a one-parameter
multiplicative group, leading to universal "renormalization group"-like
first-order differential equations. The beams of characteristics of these
equations generate the full set of black hole states associated to any of these
gravitating nonlinear electrodynamics...Comment: 51 single column pages, 19 postscript figures, 2 tables, GRG tex
style; minor corrections added; final version appearing in General Relativity
and Gravitatio
Sexual risk behavior and pregnancy in detained adolescent females: a study in Dutch detention centers
<p>Abstract</p> <p>Background</p> <p>The purpose of this study was to investigate the lifetime prevalence of teenage pregnancy in the histories of detained adolescent females and to examine the relationship between teenage pregnancy on the one hand and mental health and sexuality related characteristics on the other.</p> <p>Methods</p> <p>Of 256 admitted detained adolescent females aged 12–18 years, a representative sample (N = 212, 83%) was examined in the first month of detention. Instruments included a semi-structured interview, standardized questionnaires and file information on pregnancy, sexuality related characteristics (sexual risk behavior, multiple sex partners, sexual trauma, lack of assertiveness in sexual issues and early maturity) and mental health characteristics (conduct disorder, alcohol and drug use disorder and suicidality).</p> <p>Results</p> <p>Approximately 20% of the participants reported having been pregnant (before detention), although none had actually given birth. Sexuality related characteristics were more prevalent in the pregnancy group, while this was not so for the mental health characteristics. Age at assessment, early maturity, sexual risk behavior, and suicidality turned out to be the best predictors for pregnancy.</p> <p>Conclusion</p> <p>The lifetime prevalence of pregnancy in detained adolescent females is high and is associated with both sexuality related risk factors and mental health related risk factors. Therefore, prevention and intervention programs targeting sexual risk behavior and mental health are warranted during detention.</p
Hepatitis C Virus Infection May Lead to Slower Emergence of P. falciparum in Blood
International audienceBACKGROUND: Areas endemic for Plasmodium falciparum, hepatitis B virus (HBV) and hepatitis C virus (HCV) overlap in many parts of sub-Saharan Africa. HBV and HCV infections develop in the liver, where takes place the first development stage of P. falciparum before its further spread in blood. The complex mechanisms involved in the development of hepatitis may potentially influence the development of the liver stage of malaria parasites. Understanding the molecular mechanisms of these interactions could provide new pathophysiological insights for treatment strategies in Malaria. METHODOLOGY: We studied a cohort of 319 individuals living in a village where the three infections are prevalent. The patients were initially given a curative antimalarial treatment and were then monitored for the emergence of asexual P. falciparum forms in blood, fortnightly for one year, by microscopy and polymerase chain reaction. PRINCIPAL FINDINGS: At inclusion, 65 (20.4%) subjects had detectable malaria parasites in blood, 36 (11.3%) were HBV chronic carriers, and 61 (18.9%) were HCV chronic carriers. During follow-up, asexual P. falciparum forms were detected in the blood of 203 patients. The median time to P. falciparum emergence in blood was respectively 140 and 120 days in HBV- and HBV+ individuals, and 135 and 224 days in HCV- and HCV+ individuals. HCV carriage was associated with delayed emergence of asexual P. falciparum forms in blood relative to patients without HCV infection. CONCLUSIONS: This pilot study represents first tentative evidence of a potential epidemiological interaction between HBV, HCV and P. falciparum infections. Age is an important confounding factor in this setting however multivariate analysis points to an interaction between P. falciparum and HCV at the hepatic level with a slower emergence of P. falciparum in HCV chronic carriers. More in depth analysis are necessary to unravel the basis of hepatic interactions between these two pathogens, which could help in identifying new therapeutic approaches against malaria
Foundations of Black Hole Accretion Disk Theory
This review covers the main aspects of black hole accretion disk theory. We
begin with the view that one of the main goals of the theory is to better
understand the nature of black holes themselves. In this light we discuss how
accretion disks might reveal some of the unique signatures of strong gravity:
the event horizon, the innermost stable circular orbit, and the ergosphere. We
then review, from a first-principles perspective, the physical processes at
play in accretion disks. This leads us to the four primary accretion disk
models that we review: Polish doughnuts (thick disks), Shakura-Sunyaev (thin)
disks, slim disks, and advection-dominated accretion flows (ADAFs). After
presenting the models we discuss issues of stability, oscillations, and jets.
Following our review of the analytic work, we take a parallel approach in
reviewing numerical studies of black hole accretion disks. We finish with a few
select applications that highlight particular astrophysical applications:
measurements of black hole mass and spin, black hole vs. neutron star accretion
disks, black hole accretion disk spectral states, and quasi-periodic
oscillations (QPOs).Comment: 91 pages, 23 figures, final published version available at
http://www.livingreviews.org/lrr-2013-
Detection of sexually transmitted infection and human papillomavirus in negative cytology by multiplex-PCR
<p>Abstract</p> <p>Background</p> <p>The aim of this study was to determine the prevalence of human papillomavirus (HPV) and 15 species that cause sexually transmitted infections (STIs) in negative cytology. In addition, we compared the diagnostic performance of multiplex polymerase chain reaction (PCR) with widely available techniques used to detect HPV.</p> <p>Methods</p> <p>We recruited 235 women of reproductive age who had negative cytology findings in a liquid-based cervical smear. STIs were identified by multiplex PCR, and HPV genotypes by multiplex PCR, hybrid capture 2, and DNA microaray; discordant results were analyzed by direct sequencing.</p> <p>Results</p> <p>Approximately 96.6% of patients with negative cytology results were positive for pathogens that cause STIs. The pathogens most frequently detected were <it>Gardnerella vaginalis, Ureaplasma urealyticum</it>. The incidence of HPV in negative cytology was 23.3%. Low-risk HPV infection was significantly correlated with <it>Chalmaydia trachomatis</it>, and high-risk HPV infection was significantly correlated with <it>Group β streptococcus</it>. The analytical sensitivities of the multiplex PCR and DNA microarray were higher than 80%, and the analytical specificity was nearly 100% for all tests.</p> <p>Conclusions</p> <p>Multiplex PCR yielded results that most of patients with negative cytology were positive for pathogens that cause STIs, and were more similar to that of DNA microarray, than that of hybrid capture 2 in terms of analytical sensitivity and prediction value of HPV infection.</p
Determining the interviewer effect on CQ Index outcomes: a multilevel approach
<p>Abstract</p> <p>Background</p> <p>The CQ Index for the elderly, a quality-of-care questionnaire administered by conducting interviews, is used to assess clients' experiences in Dutch nursing homes and homes for the elderly. This article describes whether inter-interviewer differences influence the perceived quality of healthcare services reported by residents, the size of this interviewer effect and the influence of the interviewer characteristics on CQ Index dimensions for public reporting.</p> <p>Methods</p> <p>Data from 4345 questionnaires was used. Correlations were calculated, reliability analyses were performed, and a multilevel analysis was used to calculate the degree of correlation between two interviewers within one health care institution. Five models were constructed and the Intra Class Correlation (ICC) was calculated. Healthcare institutions were given 1-5 stars on every quality dimensions (1 = worst and 5 = best), adjusted for resident and interviewer characteristics. The effect of these characteristics on the assignment of the stars was investigated.</p> <p>Results</p> <p>In a multilevel approach, the ICC showed a significant amount of variance on five quality dimensions. Of the interviewer characteristics, only previous interviewing experience, the reason of interviewing and general knowledge of health care had a significant effect on the quality dimensions. Adjusting for interviewer characteristics did not affect the overall star assignment to the institutions regarding 7 of 12 quality dimensions. For the other five dimensions (Shared decision-making, Meals, Professional competency, Autonomy, and Availability of personnel) a minor effect was found.</p> <p>Conclusions</p> <p>We have shown that training, the use of experienced interviewers, written instructions, supervision and educational meetings do not automatically prevent interviewer effects. While the results of this study can be used to improve the quality of services provided by these institutions, several CQ index dimensions should be interpreted with caution for external purposes (accountability and transparency).</p
Characteristics of ascitic fluid from patients with suspected spontaneous bacterial peritonitis in emergency units at a tertiary hospital
- …