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Patient-Related Barriers to Timely Dialysis Access Preparation: A Qualitative Study of the Perspectives of Patients, Family Members, and Health Care Providers
Rational & Objective
A key aspect of smooth transition to dialysis is the timely creation of a permanent access. Despite early referral to kidney care, initiation onto dialysis is still suboptimal for many patients, which has clinical and cost implications. This study aimed to explore perspectives of various stakeholders on barriers to timely access creation.
Study Design
Qualitative study.
Setting & Participants
Semi-structured interviews with 96 participants (response rate, 67%), including patients with stage 4 chronic kidney disease (n = 30), new hemodialysis patients with (n = 18) and without (n = 20) permanent access (arteriovenous fistula), family members (n = 19), and kidney health care providers (n = 9).
Analytical Approach
Thematic analysis.
Results
Patients reported differential levels of behavioral activation toward access creation: avoidance/denial, wait and see, or active intention. 6 core themes were identified: (1) lack of symptoms, (2) dialysis fear and practical concerns (exaggerated fear, pain, cost, lifestyle disruptions, work-related concerns, burdening their families), (3) evaluating value against costs/risks of access creation (benefits, threat of operation, viability, prompt for early initiation), (4) preference for alternatives, (5) social influences (hearsay, family involvement, experiences of others), and (6) health care provider interactions (mistrust, interpersonal tension, lack of clarity on information). Themes were common to all groups, whereas nuanced perspectives of family members and health care providers were noted in some subthemes.
Limitations
Response bias.
Conclusions
Individual, interpersonal, and psychosocial factors compromise dialysis preparation and contribute to suboptimal dialysis initiation. Our findings support the need for interventions to improve patient and family engagement and address emotional concerns and misperceptions about preparing for dialysis
A novel route to phase formation of cobalt oxyhydrates using KMnO4 as an oxidizing agent
We have first succeefully synthesized the sodium cobalt oxyhydrate
superconductors using KMnO4 as a de-intercalating and oxidizing agent. It is a
novel route to form the superconductive phase of NaxCoO2.yH2O without resorting
to the commonly used Br2/CH3CN solution. The role of the KMnO4 is to
de-intercalate the Na+ from the parent compound Na0.7CoO2 and oxidize the Co
ion as a result. The higher molar ratio of KMnO4 relative to the sodium content
tends to remove more Na+ from the parent compound and results in a slight
expansion of the c-axis in the unit cell. The superconducting transition
temperature is 4.6-3.8 K for samples treated by the aqueous KMnO4 solution with
the molar ratio of KMnO4 relative to the sodium content in the range of 0.3 and
2.29.Comment: 10 pages, 3 figure
Magnetic and Metal-Insulator Transitions in beta-Na0.5CoO2 and gamma-K0.5CoO2 -NMR and Neutron Diffraction Studies-
Co-oxides beta-Na0.5CoO2 and gamma-K0.5CoO2 have been prepared by the Na
de-intercalation from alpha-NaCoO2 and by the floating-zone method,
respectively. It has been found that successive phase transitions take place at
temperatures Tc1 and Tc2 in both systems. The appearance of the internal
magnetic field at Tc1 with decreasing temperature T indicates that the
antiferromagnetic order exists at T < Tc1, as in gamma-Na0.5CoO2. For
beta-Na0.5CoO2, the transition temperatures and the NMR parameters determined
from the data taken for magnetically ordered state are similar to those of
gamma-Na0.5CoO2, indicating that the difference of the stacking ways of the
CoO2 layers between these systems do not significantly affect their physical
properties. For gamma-K0.5CoO2, the quantitative difference of the physical
quantities are found from those of beta- and gamma-Na0.5CoO2. The difference
between the values of Tci (i = 1 and 2) of these systems might be explained by
considering the distance between CoO2 layers.Comment: 8 pages, 14 figures, 1 Tabl
Thermal and Electrical Properties of gamma-NaxCoO2 (0.70 < x < 0.78)
We have performed specific heat and electric resistivity measurements of
NaCoO (-0.78). Two anomalies have been observed in the
specific heat data for , corresponding to magnetic transitions at
K and K reported previously. In the electrical
resistivity, a steep decrease at and a bending-like variation at
(=120K for ) have been observed. Moreover, we have investigated
the -dependence of these parameters in detail. The physical properties of
this system are very sensitive to , and the inconsistent results of previous
reports can be explained by a small difference in . Furthermore, for a
higher value, a phase separation into Na-rich and Na-poor domains occurs as
we previously proposed, while for a lower value, from characteristic
behaviors of the specific heat and the electrical resistivity at the
low-temperature region, the system is expected to be in the vicinity of the
magnetic instability which virtually exists below .Comment: 4 pages (3 figures included) and an extra figure (gif), to be
published in J. Phys. Soc. Jpn. 73 (9) with possible minor revision
Large enhancement of the thermopower in NaCoO at high Na doping
Research on the oxide perovskites has uncovered electronic properties that
are strikingly enhanced compared with those in conventional metals. Examples
are the high critical temperatures of the cuprate superconductors and the
colossal magnetoresistance in the manganites. The conducting layered cobaltate
displays several interesting electronic phases as is varied
including water-induced superconductivity and an insulating state that is
destroyed by field. Initial measurements showed that, in the as-grown
composition, displays moderately large thermopower and
conductivity . However, the prospects for thermoelectric cooling
applications faded when the figure of merit was found to be small at this
composition (0.60.7). Here we report that, in the poorly-explored
high-doping region 0.75, undergoes an even steeper enhancement. At the
critical doping 0.85, (at 80 K) reaches values 40 times
larger than in the as-grown crystals. We discuss prospects for low-temperature
thermoelectric applications.Comment: 6 pages, 7 figure
Effect of Condensed Tannin in Lotus Corniculatus and Lotus Pedunculatus on Digestion of Rubisco in the Rumen
The in vitro precipitation of ribulose-1,5-bisphosphate carboxylase (Rubisco) by condensed tannin (CT) extracted from Lotus corniculatus and Lotus pedunculatus and the effect of these CT on the in vitro rumen degradation of Rubisco was used to compare the reactivity of these CT. The chemical structure of CT from Lotus corniculatus was homogenous with epicatechin stereochemistry and mostly procyanidin units. The CT from Lotus pedunculatus was heterogenous with mostly prodelphinidin units. The amount of CT required to precipitate all the Rubisco when total soluble leaf protein was incubated with CT from Lotus corniculatus and Lotus pedunculatus was similar. Although CT from both species were able to reduce the in vitro degradation of Rubisco, CT from Lotus corniculatus was less effective than CT from Lotus pedunculatus at reducing this degradation
Extended magic phase in twisted graphene multilayers
Theoretical and experimental studies have verified the existence of ``magic
angles'' in twisted bilayer graphene, where the twist between layers gives rise
to flat bands and consequently highly correlated phases. Narrow bands can also
exist in multilayers with alternating twist angles, and recent theoretical work
suggests that they can also be found in trilayers with twist angles between
neighboring layers in the same direction. We show here that flat bands exist in
a variety of multilayers where the ratio between twist angles is close to
coprime integers. We generalize previous analyses, and, using the chiral limit
for interlayer coupling, give examples of many combinations of twist angles in
stacks made up of three and four layers which lead to flat bands. The technique
we use can be extended to systems with many layers. Our results suggest that
flat bands can exist in graphene multilayers with angle disorder, that is,
narrow samples of turbostatic graphite.Comment: Main text: 4 pages, 4 figures -- Supplementary Material: 15 pages, 13
figure
IL-33 ameliorates Alzheimer’s disease-like pathology and cognitive decline
Alzheimer’s disease (AD) is a devastating condition with no known effective treatment. AD is characterized by memory loss as well as impaired locomotor ability, reasoning, and judgment. Emerging evidence suggests that the innate immune response plays a major role in the pathogenesis of AD. In AD, the accumulation of β-amyloid (Aβ) in the brain perturbs physiological functions of the brain, including synaptic and neuronal dysfunction, microglial activation, and neuronal loss. Serum levels of soluble ST2 (sST2), a decoy receptor for interleukin (IL)-33, increase in patients with mild cognitive impairment, suggesting that impaired IL-33/ST2 signaling may contribute to the pathogenesis of AD. Therefore, we investigated the potential therapeutic role of IL-33 in AD, using transgenic mouse models. Here we report that IL-33 administration reverses synaptic plasticity impairment and memory deficits in APP/PS1 mice. IL-33 administration reduces soluble Aβ levels and amyloid plaque deposition by promoting the recruitment and Aβ phagocytic activity of microglia; this is mediated by ST2/p38 signaling activation. Furthermore, IL-33 injection modulates the innate immune response by polarizing microglia/macrophages toward an antiinflammatory phenotype and reducing the expression of proinflammatory genes, including IL-1β, IL-6, and NLRP3, in the cortices of APP/PS1 mice. Collectively, our results demonstrate a potential therapeutic role for IL-33 in AD
NMR studies of Successive Phase Transitions in Na0.5CoO2 and K0.5CoO2
59Co- and 23Na-NMR measurements have been carried out on polycrystalline and
c-axis aligned samples of Na0.5CoO2, which exhibits successive transitions at
temperatures T = 87 K (= Tc1) and T = 53 K (= Tc2). 59Co-NMR has also been
carried out on c-axis aligned crystallites of K0.5CoO2 with similar successive
transitions at Tc1 ~ 60 K and Tc2 ~ 20 K. For Na0.5CoO2, two sets of three NMR
lines of 23Na nuclei explained by considering the quadrupolar frequencies nuQ
~1.32 and 1.40 MHz have been observed above Tc1, as is expected from the
crystalline structure. Rather complicated but characteristic variation of the
23Na-NMR spectra has been observed with varying T through the transition
temperatures, and the internal fields at two crystallographically distinct Na
sites are discussed on the basis of the magnetic structures reported
previously. The internal fields at two distinct Co sites observed below Tc1 and
the 591/T1-T curves of Na0.5CoO2 and K0.5CoO2 are also discussed in a
comparative way.Comment: 7 pages, 10 figures, submitted to J. Phys. Soc. Jpn, correction is
made in right colum of p6 (35th line) as K0.5CoO2-->Na0.5CoO
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