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B[e] supergiants (sgB[e]) are rare objects whose evolutionary stage remains uncertain. Observationally, they display strong Balmer emission lines, infrared excess, and intrinsic polarization, indicating a non-spherical circumstellar envelope. We present a study of the sgB[e] RMC 82, using new spectropolarimetric data complemented by photometry from the ultraviolet (UV) to the mid-infrared. Our two-component model comprises a slow, dense equatorial wind wherein dust grains form and a fast polar wind. We applied the hdust radiative transfer code and Bayesian statistics to infer the parameters from a grid of 3240 pre-computed models. The model accurately reproduces the spectral energy distribution and polarized spectrum, but struggles to match the H α emission. Our results suggest a large mass-loss rate of |$6.6 \times 10^{-6}\, \mathrm{{\rm M}_{\odot }\, yr^{-1}\, sr^{-1}}$|⁠. The dense wind is confined within an opening angle of 11°. The hottest dust grains are located at 277  R * with a temperature of 870 K. The dust grains are porous, with a density of 0.051  |$\rm {g\, cm^{-3}}$|⁠. The central star was found to be significantly hotter than previous estimates (T eff =  |$27\, 000$|  K). By comparing models with different components, we find that gas reprocesses a significant amount of UV radiation, shielding the dust. However, the dust also scatters UV photons back to the inner disc, increasing its temperature and H α emission. We conclude that self-consistent models, that account for the gas–dust interplay in the envelope, are essential for studying sgB[e] and similar objects. [ABSTRACT FROM AUTHOR]

A novel Positron Emission Tomography system, based on plastic scintillators, is being developed by the J-PET Collaboration. In this article, we present the simulation results of the scatter fraction, representing one of the parameters crucial for background studies defined in the NEMA-NU-2- 2012 norm. We elaborate an event selection methods allowing to suppress events in which gamma quanta were scattered in the phantom or underwent the multiple scattering in the detector. The estimated scatter fraction for the single-layer J-PET scanner varies from 37% to 53% depending on the applied energy threshold. [ABSTRACT FROM AUTHOR]

Anemia is a common complication of chronic kidney disease (CKD) and is associated with increased mortality and reduced health-related quality of life. Anemia is characterized by a decrease in hemoglobin, the iron-rich protein that the body uses for oxygen transport. Iron is required to produce hemoglobin, and disruptions in the iron homeostasis can lead to iron-deficiency anemia. Management of anemia in individuals with CKD is typically performed by a team of physicians, nurse practitioners, physician assistants, or registered nurses. Throughout the care continuum, the management can be enhanced by multidisciplinary care, and individuals with CKD can benefit from the involvement of other specialties, with dietitians/nutritionists playing an important role. However, a key area of unmet clinical need is how to assess and address iron-deficiency anemia. This review aims to provide an overview of iron-deficiency anemia in CKD and how this may be diagnosed and managed by the entire kidney care team, such as describing the mechanisms underlying iron homeostasis, the complications of iron-deficiency anemia, and the current challenges associated with its diagnosis and treatment in CKD. Opportunities for each multidisciplinary team member to add value to the care of individuals with CKD and iron-deficiency anemia are also described., (© 2023 The Authors.)

With an increased emphasis on home dialysis therapies (HDTs), and to ensure nephrology nurses have a voice in health policy discussions and decisions, the American Nephrology Nurses Association (ANNA) initiated the Home Dialysis Therapies Task Force. ANNA fully supports the increased utilization of HDTs and wants to ensure every individual has the option of HDT and deserves an RN in their care. Careful consideration must be given to the impact of legislative initiatives aimed at the nursing shortage and increasing the use of HDTs on delivery of safe care and RN practice. The HDT Task Force implemented a Think Tank to explore and delineate the role of nephrology RNs in HDT to ensure a safe and informed transition to HDT for individuals with kidney failure. The mission was to gather and analyze information on the role of the nephrology RN in HDTs, clarify RN-specific tasks versus tasks that may be delegated to support staff, and gather and gain insight into barriers to HDTs., Competing Interests: The authors reported no actual or potential conflict of interest in relation to this nursing continuing professional development (NCPD) activity., (Copyright© by the American Nephrology Nurses Association.)

The End-Stage Renal Disease Treatment (ETC) Model, an aspect of the Advancing American Kidney Health Initiative implemented by the Centers for Medicare and Medicaid Services (CMS) in 2019, is designed to shift the predominant in-center hemodialysis dialysis model in the United States to a home dialysis model. This shift represents a monumental change in the treatment of end stage kidney failure and is occurring amid a strained nursing workforce. The CMS Conditions for Coverage for dialysis facilities mandate registered nurse responsibility for the conduct of patients' home dialysis training, and the current nursing shortage presents challenges because the need for nephrology nurses will increase to meet the growing demand for home dialysis during the ETC implementation period. As the ETC Model is implemented in randomly selected dialysis facilities across the United States, nephrology nurses must have leading roles as full partners with CMS and other stakeholders for the mutual determination of short- and long-term solutions for meeting the growing home dialysis training demands., Competing Interests: The authors reported no actual or potential conflict of interest in relation to this nursing continuing professional development (NCPD) activity., (Copyright© by the American Nephrology Nurses Association.)

This paper is part of the Clinical Trial Endpoints for Dialysis Vascular Access Project of the American Society of Nephrology Kidney Health Initiative. The purpose of this project is to promote research in vascular access by clarifying trial end points which would be best suited to inform decisions in those situations in which supportive clinical data are required. The focus of a portion of the project is directed toward arteriovenous access. There is a potential for interventional studies to be directed toward any of the events that may be associated with an arteriovenous access' evolution throughout its life cycle, which has been divided into five distinct phases. Each one of these has the potential for relatively unique problems. The first three of these correspond to three distinct stages of arteriovenous access development, each one of which has been characterized by objective direct and/or indirect criteria. These are characterized as: stage 1-patent arteriovenous access, stage 2-physiologically mature arteriovenous access, and stage 3-clinically functional arteriovenous access. Once the requirements of a stage 3-clinically functional arteriovenous access have been met, the fourth phase of its life cycle begins. This is the phase of sustained clinical use from which the arteriovenous access may move back and forth between it and the fifth phase, dysfunction. From this phase of its life cycle, the arteriovenous access requires a maintenance procedure to preserve or restore sustained clinical use. Using these definitions, clinical trial end points appropriate to the various phases that characterize the evolution of the arteriovenous access life cycle have been identified. It is anticipated that by using these definitions and potential end points, clinical trials can be designed that more closely correlate with the goals of the intervention and provide appropriate supportive data for clinical, regulatory, and coverage decisions., (Copyright © 2018 by the American Society of Nephrology.)

Background/aims: The calcium-sensing receptor gene (CASR) rs1801725 variant is responsible for a non-conservative amino-acid change (A986S) in the calcium-sensing receptor cytoplasmic tail. We hypothesized that rs1801725 polymorphism might be helpful in understanding Ca-related abnormalities in HD patients., Methods: In 1215 subjects (245 on cinacalcet), we determined the associations of rs1801725 with secondary hyperparathyroidism (sHPT)-related laboratory parameters, PTH-decreasing effect of cinacalcet hydrochloride, coronary artery disease (CAD), myocardial infarction (MI), nephrolithiasis-related ESRD, and mortality. CASR rs7652589(AT) haplotypes and rs1801725 epistatic interactions with vitamin D signaling pathway genes were examined for associations with selected phenotypes., Results: The rs1801725 variant allele showed an increasing independent effect on plasma PTH (Pcorrected = 0.009). CASR rs7652589_rs1801725 AT haplotype was associated with 1.7-fold higher frequency of PTH levels over 437 pg/mL than the reference haplotype GG (P = 0.001). CASR rs7652589_rs1801725 AG haplotype was 1.5-fold more frequent in nephrolithiasis-related ESRD than the GG haplotype (P = 0.004). There were no significant associations between rs1801725, CAD, MI, and response to cinacalcet. Variant homozygosity of rs1801725 correlated independently with higher infection-related mortality compared with heterozygosity (HR 7.95, 95%CI 2.15 - 29.37, P = 0.003) and major homozygosity (HR 5.89, 95%CI 1.69 - 20.55, P = 0.040). CASR rs1801725 did not show epistatic interactions with vitamin D signaling pathway genes concerning tested associations., Conclusion: The variant allele of CASR rs1801725 solely and together with the variant allele of rs7652589 increases risk of more advanced sHPT. Homozygosity of the rs1801725 variant allele contributes to infection-related mortality in HD patients., (© 2018 The Author(s). Published by S. Karger AG, Basel.)

Background: To evaluate arteriovenous graft patency when failing grafts are treated with Viabahn covered stents vs percutaneous angioplasty (PTA) alone., Methods: A retrospective review of all patients that underwent endovascular interventions for failing grafts at a single institution between January 2010 and July 2013 was performed. Forty-four patients were identified who were treated with PTA alone (11) and with Viabahn stent grafts (33) for stenoses in the venous to graft anastomoses. Patient demographics, procedural success, and intraoperative complications were recorded as well as graft patency at 3, 6, and 12 months. Graft patency was reviewed and compared with PTA alone., Results: There was no statistically significant difference between the 2 groups regarding gender, frequency of diabetes, hypertension, coronary artery disease, or peripheral arterial disease. Primary technical success defined as residual stenosis 10% or less was achieved in 100% of the cases. Follow-up was determined by flow velocities during dialysis and ultrasound imaging in the vascular laboratory. At 12 months 87.8% (29/33) grafts with stents were functional vs 36.4% (4/11) of those with PTA alone. Primary patency of the stent group was 61%, 52%, and 42% at 3, 6, and 12 months respectively vs the PTA group 64%, 45%, and 9%., Conclusions: Grafts treated with Viabahn covered stents for outflow stenosis have a superior patency to PTA alone, 12 months after treatment; although earlier post treatment results are comparable., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Herein we report the dependency of the performance (uptake, activity, stability) of hydrophilic glucose-6-phosphate dehydrogenase (G6PDH) onto mesoporous cellular foams (MCF) grafted with aminosilanes of different chain length. The resulting hydrophobic-hydrophilic contrast was carefully evaluated by combined argon and water sorption and quantified with a newly developed hydrophilicity index suitable for the characterization of large-pore materials. The enzymatic behaviour was influenced by electrostatic and hydrophobic interactions between both reaction partners due to the creation of specific microenvironments inside the pore system. The microenvironment created by the materials with high hydrophobicity did not contribute to the beneficial electrostatic interactions of the charged amine groups by increased hydrophobic forces instead a competition of both forces was present. Thus an improved biocatalytic performance was not observed for materials with high hydrophobicity but short-chain functionalized MCFs led to highly stable and active biocatalysts.

End-of-life care is underutilized in patients with kidney failure despite high mortality and multiple comorbid conditions. Recent revisions in the Medicare Benefit Policy Manual and the Conditions for Coverage for End-Stage Renal Disease provide a clearer understanding for referral to palliative and hospice care. There are recommendations to improve end-of-life care in this complicated population.

Gene expression is regulated by a complex interplay between binding and the three-dimensional arrangement of transcription factors with RNA polymerase and DNA. Previous studies have supported a direct role for DNA bending and conformation in gene expression, which suggests that agents that induce bends in DNA might be able to control gene expression. To test this hypothesis, we examined the effect of triple-helix-forming oligonucleotide (TFO) bending agents on the transcription of luciferase in an in vitro transcriptional/translational system. We find that transcription is regulated only by a TFO that induces a bend in the DNA. Related TFOs that do not induce bends in DNA have no effect on transcription. Reporter expression can be increased by as much as 80 % or decreased by as much as 50 % depending on the phasing of the upstream bend relative to the promoter. We interpret the results as follows: when the bend is positioned such that the upstream DNA is curved toward the RNA polymerase on the same DNA face, transcription is enhanced. When the upstream DNA is curved away, transcription is attenuated. These results support the hypothesis that DNA-bending agents might have the capability to regulate gene expression, thereby opening up a previously undervalued avenue in research on the artificial control of gene expression.

Because it provides greater and more durable weight reduction than behavioral and pharmacological interventions for the morbidly obese, the number of bariatric surgeries is increasing - one such procedure is the Roux-en-Y gastric bypass. A cross-sectional study was conducted to examine incision care knowledge and discharge concerns of patients who had undergone this type of gastric bypass bariatric surgery. Participants (N = 31; 28 women, three men; mean age 45 years), recruited from a bariatric surgery center in a large, urban teaching hospital, had undergone a Roux-en-Y gastric bypass by either the open (n = 29) or laparoscopic (n = 2) method. Patients scheduled to be discharged home, 21 years of age or older, and able to understand and respond in English were eligible to participate. Participants completed questionnaires that included demographic information and rating scales regarding incision care knowledge, fears, and discharge concerns. Mean time from hospital admission to study participation was 1.1 days (SD = 3 days). Knowledge of incision care and amount of information received about incision care were rated low. The five most frequently mentioned postdischarge concerns included bowel trouble at home, wound pain at home, looking for wound complications, watching for wound infection, and activity limitations. The higher the amount of information received about incision care, the higher the patient's knowledge (r = .57, P <.001). Lower incision care knowledge scores were correlated with a higher fear of incision care (r = .46, P = .008) and patients reporting greater pain had more concerns about discharge (r = .49, P <.005). Little is known about preparing the bariatric surgery patient for discharge home. To improve outcomes, research that examines issues including discharge teaching methods, patient concerns, and information for persons undergoing bariatric surgery is needed.

A novel DNA binding agent based upon a triaza-cyclopenta[b]phenanthrene scaffold, compound 1, has been synthesized. dsDNA binding analysis of this compound using the ethidium bromide displacement assay indicated a preference for GC-rich sequences. However, equilibrium dialysis experiments against a variety of nucleic acids showed that the target compound bound about 20-fold tighter to G-quartet DNA than to dsDNA under physiological salt concentrations. The binding of 1 to G-quartet DNA was verified by the ability of the compound to promote the formation of the quartet and to compete with TmPyP4 for binding to the quadruplex. Given the importance of G-quartet binding agents in the treatment of cancer and in the understanding of drug-DNA interactions, 1 and its related analogs should find utility as a new class of G-quartet specific agents.

Comparative hybridization of cDNA arrays is a powerful tool for the measurement of differences in gene expression between two or more tissues. We optimized this technique and employed it to discover genes with potential for the diagnosis of ovarian cancer. This cancer is rarely identified in time for a good prognosis after diagnosis. An array of 21,500 unknown ovarian cDNAs was hybridized with labeled first-strand cDNA from 10 ovarian tumors and six normal tissues. One hundred and thirty-four clones are overexpressed in at least five of the 10 tumors. These cDNAs were sequenced and compared to public sequence databases. One of these, the gene HE4, was found to be expressed primarily in some ovarian cancers, and is thus a potential marker of ovarian carcinoma.