Kisspeptins are products of the Kiss1 gene, which bind to GPR54, a G protein-coupled receptor. Kisspeptins and GPR54 have been implicated in the neuroendocrine regulation of GnRH secretion. To test ...the hypothesis that testosterone regulates Kiss1 gene expression, we compared the expression of KiSS-1 mRNA among groups of intact, castrated, and castrated/testosterone (T)-treated male mice. In the arcuate nucleus (Arc), castration resulted in a significant increase in KiSS-1 mRNA, which was completely reversed with T replacement, whereas in the anteroventral periventricular nucleus, the results were the opposite, i.e. castration decreased and T increased KiSS-1 mRNA expression. In the Arc, the effects of T on KiSS-1 mRNA were completely mimicked by estrogen but only partially mimicked by dihydrotestosterone, a nonaromatizable androgen, suggesting that both estrogen receptor (ER) and androgen receptor (AR) play a role in T-mediated regulation of KiSS-1. Studies of the effects of T on KiSS-1 expression in mice with either a deletion of the ERα or a hypomorphic allele to the AR revealed that the effects of T are mediated by both ERα and AR pathways, which was confirmed by the presence of either ERα or AR coexpression in most KiSS-1 neurons in the Arc. These observations suggest that KiSS-1 neurons in the Arc, whose transcriptional activity is inhibited by T, are targets for the negative feedback regulation of GnRH secretion, whereas KiSS-1 neurons in the anteroventral periventricular nucleus, whose activity is stimulated by T, may mediate other T-dependent processes.
We present a combined TEVA-DGA chromatography chemistry to purify single-element fractions of Pu, Am, and Np from bulk (mg-level) U materials. Plutonium and Np are first sorbed onto TEVA resin using ...a 4 + redox adjustment with a hydroxylamine hydrochloride and sodium nitrite treatment, with U + Am eluting directly onto DGA resin. Americium is then purified from U on DGA using 0.1 M HNO
3
as a U eluent. A subsequent TEVA column is used to separate Pu from Np using hydrogen peroxide to oxidize Np into the 5 + oxidation state for elution through TEVA. Our presented TEVA-DGA method is able to produce high-purity, single-element fractions of Pu (90% recovery), Am (98% recovery), and Np (62% recovery) from mg-levels of U, and does so in three days of column chemistry.
In the course of the Fukushima nuclear accident, radionuclides were released in various forms, including so-called radiocesium-bearing microparticles (CsMP). So far, four types of CsMP were ...described: Type A is smaller in size (< 10 μm), Types B, C, and D are larger (> 100 μm). In this work, we present a novel type of CsMP (proclaimed Type E). Three particles of Type E were extracted from a contaminated blade of grass that was sampled 1.5 km from the Fukushima Daiichi nuclear power plant in late 2011. They were located using autoradiography, isolated using an optical microscope and micromanipulator, and characterized using scanning electron microscopy, energy dispersive x-ray spectroscopy, and low-level gamma-ray spectrometry. Type E CsMPs are 10–20 μm in size and exhibit an unusually low and barely detectable
137
Cs activity of only ≤ 10 mBq per particle. Their brittle and fragile character may indicate a high surface tension.
Uranium isotopic composition can provide valuable information about the history and provenance of a nuclear material; therefore, uranium isotopic analyses are frequently made in the nuclear ...forensics, safeguards, and environmental monitoring communities. These measurements have always presented challenges due to the extreme variability in the relative abundance between the major (235U, 238U) and minor (233U, 234U, 236U) isotopes of uranium. The recently developed ATONA (Atto- to Nano-Amp) amplification system paired with Faraday cup detectors has a large dynamic range and low noise floor making it ideal for measuring uranium isotopic ratios in materials of both natural and anthropogenic origin. A wide variety of certified reference materials were analyzed to investigate the utility of the ATONA amplification system for determining uranium isotopic composition in samples ranging from depleted to highly enriched. The ATONA amplifiers provide nearly an order of magnitude improvement in external reproducibility over 1011 Ω amplifiers when measuring the minor 234U/238U ratio in isotopically natural and depleted samples and when paired with a secondary electron multiplier can measure very low relative abundance uranium isotopes (i.e., 236U).
Former inmates are at high risk for death from drug overdose, especially in the immediate post-release period. The purpose of the study is to understand the drug use experiences, perceptions of ...overdose risk, and experiences with overdose among former prisoners.
This qualitative study included former prison inmates (N=29) who were recruited within two months after their release. Interviewers conducted in-person, semi-structured interviews which explored participants' experiences and perceptions. Transcripts were analyzed utilizing a team-based method of inductive analysis.
The following themes emerged: 1) Relapse to drugs and alcohol occurred in a context of poor social support, medical co-morbidity and inadequate economic resources; 2) former inmates experienced ubiquitous exposure to drugs in their living environments; 3) intentional overdose was considered "a way out" given situational stressors, and accidental overdose was perceived as related to decreased tolerance; and 4) protective factors included structured drug treatment programs, spirituality/religion, community-based resources (including self-help groups), and family.
Former inmates return to environments that strongly trigger relapse to drug use and put them at risk for overdose. Interventions to prevent overdose after release from prison may benefit from including structured treatment with gradual transition to the community, enhanced protective factors, and reductions of environmental triggers to use drugs.
Summary Background Human retinal pigment epithelial (RPE) cells produce levodopa and their transplantation into the striatum might improve continuity of administration compared with that achieved ...with oral levodopa. We aimed to assess the safety, tolerability, and efficacy of transplantation of microcarrier-bound human RPE cells versus a sham surgery control in patients with advanced Parkinson's disease. Methods In this randomised, double-blind study eligible patients were aged 36–70 years, had been symptomatic for at least 5 years, were in Hoehn and Yahr stage 3–4 and had unified Parkinson's disease rating scale (UPDRS) motor scores of 38–70 when off medication (off state), and had symptoms that responded to oral levodopa but were insufficiently controlled by optimised pharmacotherapy. Randomisation was done in a 1:1 ratio. Only the neurosurgical team was aware of treatment assignments. During stereotactic transplantation around 325 000 cells per side were injected into the postcommissural putamen; sham surgery patients received partial burr holes. The primary efficacy endpoint was change in UPDRS off-state motor score at 12 months. This study is registered with ClinicalTrials.gov , number NCT00206687. Findings Of 71 enrolled patients, 35 underwent cell transplantation and 36 sham surgery. Change in mean motor scores did not differ significantly between groups (−10·5 SD 10·26 for transplantation vs −10·1 SD 12·26 for sham surgery, p=0·9). The overall rate of adverse events was similar in the two study groups, although the number attributable to surgery or RPE cells (mostly neurological or psychiatric) was higher in transplant recipients. Two and seven patients died in the sham surgery and transplantation group, respectively; one death in the latter group was possibly related to surgery or RPE cells. Interpretation Transplantation of human RPE cells provided no antiparkinsonian benefits compared with sham surgery. Funding Bayer HealthCare AG.
A nuclear forensics investigation involving a uranium ore concentrate relies on accurate and precise analysis of impurities. Analytical data defensibility requires the use of reference materials as ...part of quality control. This study presents a compilation of trace element concentration results of the CUP-2 Uranium Ore Concentrate Standard measured by 11 different laboratories. The laboratories employed various dissolution methods, analytical preparation methods, and instrumental platforms. The data presented here contain concentrations of 66 impurities with up to 138 individual data points for each impurity. Consensus values have been assigned to each impurity following a statistical analysis of the data set.
In many states, budget constraints are prompting earlier release of prison inmates. Prior studies have demonstrated elevated mortality rates in the post-release period but little is known about the ...health experiences of former inmates in the transition from prison to the community. The objective of this study was to understand the health-seeking experiences, perceptions of risk, and medical and mental health needs of former prisoners in the first two months after release from prison. Participants consisted of 29 former inmates within the first two months after their release from prison to the Denver, Colorado area. Using qualitative methods, trained interviewers conducted individual, in-person, semi-structured interviews exploring participants' experiences with health, mental health, and health care since release. Interview transcripts were coded and analyzed utilizing a team-based approach to inductive analysis. We found that health-related behavior occurred in the context of a complex life experience, with logistical problems exacerbated by emotional distress. Major themes included 1) transitional challenges; 2) cognitive responses including perceptions about personal risk, knowledge and priorities; 3) emotional responses including pronounced stress, fear, anxiety, disappointment; and 4) health behaviors. Former inmates reported multiple challenges, poor transitional preparation preceding release, and inadequate or absent continuity of mental and physical health care in the context of significant emotional distress and anxiety. Improved release planning, coordination between the medical, mental health and criminal justice systems may reduce the risk of poor health outcomes for this population.
Particulate isotopic analysis in nuclear forensics has developed rapidly during the past two decades due to technical advances in determining the isotopic composition of individual particles. This ...paper introduces basic statistical concepts that can be applied by analysts to understand the importance of statistical adequacy when interpretating particle data. While these basic statistical methods provide a useful point-of-entry to particle data analysis, more sophisticated statistical and modeling approaches are needed to extract maximal information from such datasets in the future.
Modern mass spectrometry and separation techniques have made measurement of major uranium isotope ratios a routine task; however accurate and precise measurement of the minor uranium isotopes remains ...a challenge as sample size decreases. One particular challenge is the presence of isobaric interferences and their impact on the accuracy of minor isotope
234
U and
236
U measurements. We present techniques used for routine U isotopic analysis of environmental nuclear safeguards samples and evaluate polyatomic interferences that negatively impact accuracy as well as methods to mitigate their impacts.
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