The BAR domain protein superfamily is involved in membrane invagination and endocytosis, but its role in organizing membrane proteins has not been explored. In particular, the membrane scaffolding ...protein BIN1 functions to initiate T-tubule genesis in skeletal muscle cells. Constitutive knockdown of BIN1 in mice is perinatal lethal, which is associated with an induced dilated hypertrophic cardiomyopathy. However, the functional role of BIN1 in cardiomyocytes is not known. An important function of cardiac T-tubules is to allow L-type calcium channels (Cav1.2) to be in close proximity to sarcoplasmic reticulum-based ryanodine receptors to initiate the intracellular calcium transient. Efficient excitation-contraction (EC) coupling and normal cardiac contractility depend upon Cav1.2 localization to T-tubules. We hypothesized that BIN1 not only exists at cardiac T-tubules, but it also localizes Cav1.2 to these membrane structures. We report that BIN1 localizes to cardiac T-tubules and clusters there with Cav1.2. Studies involve freshly acquired human and mouse adult cardiomyocytes using complementary immunocytochemistry, electron microscopy with dual immunogold labeling, and co-immunoprecipitation. Furthermore, we use surface biotinylation and live cell confocal and total internal fluorescence microscopy imaging in cardiomyocytes and cell lines to explore delivery of Cav1.2 to BIN1 structures. We find visually and quantitatively that dynamic microtubules are tethered to membrane scaffolded by BIN1, allowing targeted delivery of Cav1.2 from the microtubules to the associated membrane. Since Cav1.2 delivery to BIN1 occurs in reductionist non-myocyte cell lines, we find that other myocyte-specific structures are not essential and there is an intrinsic relationship between microtubule-based Cav1.2 delivery and its BIN1 scaffold. In differentiated mouse cardiomyocytes, knockdown of BIN1 reduces surface Cav1.2 and delays development of the calcium transient, indicating that Cav1.2 targeting to BIN1 is functionally important to cardiac calcium signaling. We have identified that membrane-associated BIN1 not only induces membrane curvature but can direct specific antegrade delivery of microtubule-transported membrane proteins. Furthermore, this paradigm provides a microtubule and BIN1-dependent mechanism of Cav1.2 delivery to T-tubules. This novel Cav1.2 trafficking pathway should serve as an important regulatory aspect of EC coupling, affecting cardiac contractility in mammalian hearts.
Purpose
The aim of this study was to examine what personally mattered to 24 patients who received immuno-oncology (IO) therapy for stage IV non-small cell lung cancer (NSCLC), as well as their ...families and friends, to understand how they evaluated their cancer treatments and the determinants of the quality of life (QoL) of long-term survivors.
Methods
Ethnographic research was conducted with 24 patients who had responded to IO (pembrolizumab, nivolumab, atezolizumab, or durvalumab) for stage IV NSCLC, and their families and friends, evenly split among field sites in Denmark, the USA, and the UK. Data were collected using in-depth qualitative interviews, written exercises, and participant observation. Data analysis methods included interpretative phenomenological analysis, coding, and the development of grounded theory. Researchers spent 2 days with participants in their homes and accompanied them on health-related outings.
Results
Our findings reveal that long-term survivors on IO experienced their journey in two phases: one in which their cancer had taken over their lives mentally, physically, and spiritually, and another in which their cancer consumed only a part of their everyday lives. Patients who survived longer than their initial prognosis existed in a limbo state in which they were able to achieve some semblance of normalcy in spite of being identified as having a terminal condition. This limbo state impacted their life priorities, decision-making, experience of patient support, and health information-seeking behaviors, all of which shaped their definitions and experience of QoL.
Conclusions
The results of this study, which identify the specific challenges of living in limbo, where patients are able to reclaim a portion of their pre-cancer lives while continuing to wrestle with a terminal prognosis, may inform how cancer research can more effectively define and measure the QoL impacts of IO treatments. Also, they may identify approaches that the cancer community can use to support the needs of patients living in a limbo state. These experiences may not be adequately understood by the cancer community or captured by existing QoL measures, which were designed prior to the emergence of IO and without sufficient incorporation of contextual, patient-driven experience.
Implications for Cancer Survivors
Increased awareness of the specific experiences that come with long-term survival on IO may direct how resources should be spent for cancer support for patients and their families. Expanding how QoL is evaluated based on patients’ lived experiences of IO can reflect a more accurate depiction of the treatment’s benefits and harms.
Purpose: The EQ-5D is a brief, multiattribute, preference-based health status measure. This article describes the development of a statistical model for generating US population-based EQ-5D ...preference weights. Methods: A multistage probability sample was selected from the US adult civilian noninstitutional population. Respondents valued 13 of 243 EQ-5D health states using the time trade-off (TTO) method. Data for 12 states were used in econometric modeling. The TTO valuations were linearly transformed to lie on the interval -1, 1. Methods were investigated to account for interaction effects caused by having problems in multiple EQ-5D dimensions. Several alternative model specifications (eg, pooled least squares, random effects) also were considered. A modified split-sample approach was used to evaluate the predictive accuracy of the models. All statistical analyses took into account the clustering and disproportionate selection probabilities inherent in our sampling design. Results: Our D1 model for the EQ-5D included ordinal terms to capture the effect of departures from perfect health as well as interaction effects. A random effects specification of the D1 model yielded a good fit for the observed TTO data, with an overall R2 of 0.38, a mean absolute error of 0.025, and 7 prediction errors exceeding 0.05 in absolute magnitude. Conclusions: The D1 model best predicts the values for observed health states. The resulting preference weight estimates represent a significant enhancement of the EQ-5D's utility for health status assessment and economic analysis in the US.
Background
We aimed to assess the standing of acupuncture as a clinical tool in the management of trigeminal neuralgia against the current first-line drug treatment (carbamazepine) and the most ...effective surgery (microvascular decompression (MVD)).
Methods
Data regarding efficacy, side effects and cost were compiled for each of these three modalities from the PubMed and Cochrane Library databases. Patient stress was estimated according to Holmes and Rahe’s Social Readjustment Rating Scale (SRRS).
Results
Acupuncture was not significantly more effective than its corresponding control (p = 0.088), but had the greatest efficacy (mean ± 95% confidence interval) of the modalities considered (86.5% ± 5.6% compared to surgery (79.3% ± 7.7%) and pharmacotherapy (71.7% ± 2.5%), respectively). Acupuncture also had fewer mean reported side effects (22.7% ± 5.9%) compared with surgery (25.3% ± 12.6%) and pharmacotherapy (88.8% ± 25.0%), and the lowest cost; after 5 years, the cost of acupuncture was estimated to be £750, compared to £1507.73 for carbamazepine and £4878.42 for MVD. Acupuncture was the least stressful according to the SRRS (53 points), whereas surgery was second most stressful (153 points) and pharmacotherapy was the most stressful intervention to patients (217 points).
Conclusion
Acupuncture appears more effective than pharmacotherapy or surgery. Statistical analysis of side effects was not possible due to inconsistent reporting protocols, but the data suggest that acupuncture is considerably safer than pharmacotherapy or surgery. Acupuncture also appears to be the least expensive therapeutic modality to deliver long-term (65 weeks onwards), and our analysis indicated that it was less stressful to patients than pharmacotherapy or surgery. Further study into these areas and the practicality of its availability in the UK National Health Service (NHS) and other health systems is recommended.
The solid‐state packing and polymer orientation relative to the substrate are key properties to control in order to achieve high charge carrier mobilities in organic field effect transistors (OFET). ...Intuitively, shorter side chains are expected to yield higher charge carrier mobilities because of a denser solid state packing motif and a higher ratio of charge transport moieties. However our findings suggest that the polymer chain orientation plays a crucial role in high‐performing diketopyrrolopyrrole‐based polymers. By synthesizing a series of DPP‐based polymers with different branched alkyl side chain lengths, it is shown that the polymer orientation depends on the branched alkyl chain lengths and that the highest carrier mobilities are obtained only if the polymer adopts a mixed face‐on/edge‐on orientation, which allows the formation of 3D carrier channels in an otherwise edge‐on‐oriented polymer chain network. Time‐of‐flight measurements performed on the various polymer films support this hypothesis by showing higher out‐of‐plane carrier mobilities for the partially face‐on‐oriented polymers. Additionally, a favorable morphology is mimicked by blending a face‐on polymer into an exclusively edge‐on oriented polymer, resulting in higher charge carrier mobilities and opening up a new avenue for the fabrication of high performing OFET devices.
The solid state packing and morphology of semiconducting polymers play a key role in achieving high charge carrier mobilities in field effect transistors. In this work, the creation of 3D transport pathways in organic semiconductors is found to be beneficial for charge transport, and can be artificially engineered by blending polymers with different solid state packing motifs.
Heart failure is a growing epidemic, and a typical aspect of heart failure pathophysiology is altered calcium transients. Normal cardiac calcium transients are initiated by Cav1.2 channels at cardiac ...T tubules. Bridging integrator 1 (BIN1) is a membrane scaffolding protein that causes Cav1.2 to traffic to T tubules in healthy hearts. The mechanisms of Cav1.2 trafficking in heart failure are not known.
To study BIN1 expression and its effect on Cav1.2 trafficking in failing hearts.
Intact myocardium and freshly isolated cardiomyocytes from nonfailing and end-stage failing human hearts were used to study BIN1 expression and Cav1.2 localization. To confirm Cav1.2 surface expression dependence on BIN1, patch-clamp recordings were performed of Cav1.2 current in cell lines with and without trafficking-competent BIN1. Also, in adult mouse cardiomyocytes, surface Cav1.2 and calcium transients were studied after small hairpin RNA-mediated knockdown of BIN1. For a functional readout in intact heart, calcium transients and cardiac contractility were analyzed in a zebrafish model with morpholino-mediated knockdown of BIN1.
BIN1 expression is significantly decreased in failing cardiomyocytes at both mRNA (30% down) and protein (36% down) levels. Peripheral Cav1.2 is reduced to 42% by imaging, and a biochemical T-tubule fraction of Cav1.2 is reduced to 68%. The total calcium current is reduced to 41% in a cell line expressing a nontrafficking BIN1 mutant. In mouse cardiomyocytes, BIN1 knockdown decreases surface Cav1.2 and impairs calcium transients. In zebrafish hearts, BIN1 knockdown causes a 75% reduction in calcium transients and severe ventricular contractile dysfunction.
The data indicate that BIN1 is significantly reduced in human heart failure, and this reduction impairs Cav1.2 trafficking, calcium transients, and contractility.
People of lower social status tend to have greater emotional responses to stress. The present study assessed whether lower social status was related to greater emotional responses in anticipation of ...a naturalistic stressor: academic exams among college students.
College students in an introductory statistics class (N = 252; 75.81% female; 18.41% Latino, 25.10% White, 43.93% Asian, 12.56% different racial backgrounds) completed two course exams as part of this naturalistic prepost-experimental design. They provided four reports of positive, depressive, and anxious emotion - one the day before and one immediately after each exam.
As hypothesized, multilevel models (ratings nested within participants) predicting emotion indicated that students with lower mother's education had less positive emotion, more depressive emotion, and more anxious emotion the day prior to academic exams than students with higher mother's education (proportional reductions in variance PRV = .013-.020). Specifically, lower mother's education was associated with poorer well-being before but not after the exam. Exploratory models revealed that differences in emotion by mother's education were strongest for students with lower exam scores (PRV = .030-.040).
Socioeconomic status may influence college students' anticipatory distress prior to academic exams, which may impact health and academic performance.
The aim is to identify the extent to which EQ-5D is used as a clinical outcome assessment (COA) endpoint in a non-economic context in health technology assessment (HTA) decisions, regulatory ...labelling claims and published literature. Drug technology appraisals (TAs) published by HTA agencies in England, France, Germany and the USA between 2019 and 2021 were identified. Product labelling for drugs approved by the European Medicines Agency (EMA) and US Food and Drug Administration (FDA) between 2016 and 2021 were also identified. A systematic literature review (SLR) was also performed. Documents reporting EQ-5D in the context of economic evaluation only were excluded. EQ-5D data were reported for COA in 195 of 1072 (18%) published TAs, with the majority reported for Germany (
n
= 138). The EQ-5D visual analogue scale (EQ-VAS) was reported most frequently, in 68% of all TAs, and accounted for 100% of Institut für Qualität und Wirtschaftlichkeit im Gesundheitswesen (IQWiG) and 94% of Gemeinsamer Bundesausschuss (G-BA) TAs. In total, 320 drugs were approved or reviewed by the EMA and 735 by the FDA. Of these, 15 reported EQ-5D data from the EMA and 35 from the FDA; however, all EQ-5D data submitted to the FDA were reported in supporting documentation. Reporting of both EQ-5D index and EQ-VAS was most frequent, occurring in 32% of all documents. For the SLR, 329 of 4248 (8%) retrieved records were included. Reporting of both EQ-5D index and EQ-VAS was most frequent, occurring in 36% of studies. Clinical evaluation of recent drug approvals, based on regulatory, HTA and systematic literature reviews, demonstrated limited use of EQ-5D outside the context of economic evaluations. This may be due to the likelihood that the EQ-5D may lack sensitivity to detect improvement in conditions with small expected therapeutic benefit, or because the EQ-5D is not considered an adequate COA tool for clinical evaluation of treatment benefit. EQ-5D, as a COA, was more likely to be used in clinical evaluation of cancer drugs than drugs for treatment in any other disease category. HTA bodies were more likely to use the EQ-5D for COA, especially in Germany.
RATIONALE:The intracellular trafficking of connexin 43 (Cx43) hemichannels presents opportunities to regulate cardiomyocyte gap junction coupling. Although it is known that Cx43 hemichannels are ...transported along microtubules to the plasma membrane, the role of actin in Cx43 forward trafficking is unknown.
OBJECTIVE:We explored whether the actin cytoskeleton is involved in Cx43 forward trafficking.
METHODS AND RESULTS:High-resolution imaging reveals that Cx43 vesicles colocalize with nonsarcomeric actin in adult cardiomyocytes. Live-cell fluorescence imaging reveals Cx43 vesicles as stationary or traveling slowly (average speed 0.09 μm/s) when associated with actin. At any time, the majority (81.7%) of vesicles travel at subkinesin rates, suggesting that actin is important for Cx43 transport. Using Cx43 containing a hemagglutinin tag in the second extracellular loop, we developed an assay to detect transport of de novo Cx43 hemichannels to the plasma membrane after release from Brefeldin A-induced endoplasmic reticulum/Golgi vesicular transport block. Latrunculin A (for specific interference of actin) was used as an intervention after reinitiation of vesicular transport. Disruption of actin inhibits delivery of Cx43 to the cell surface. Moreover, using the assay in primary cardiomyocytes, actin inhibition causes an 82% decrease (P<0.01) in de novo endogenous Cx43 delivery to cell–cell borders. In Langendorff-perfused mouse heart preparations, Cx43/β-actin complexing is disrupted during acute ischemia, and inhibition of actin polymerization is sufficient to reduce levels of Cx43 gap junctions at intercalated discs.
CONCLUSIONS:Actin is a necessary component of the cytoskeleton-based forward trafficking apparatus for Cx43. In cardiomyocytes, Cx43 vesicles spend a majority of their time pausing at nonsarcomeric actin rest stops when not undergoing microtubule-based transport to the plasma membrane. Deleterious effects on this interaction between Cx43 and the actin cytoskeleton during acute ischemia contribute to losses in Cx43 localization at intercalated discs.
Background— Heart disease is a leading cause of mortality throughout the world. Tissue damage from vascular occlusive events results in the replacement of contractile myocardium by nonfunctional scar ...tissue. The potential of new technologies to regenerate damaged myocardium is significant, although cell-based therapies must overcome several technical barriers. One possible cell-independent alternative is the direct administration of small proteins to damaged myocardium. Methods and Results— Here we show that the secreted signaling protein stromal cell–derived factor-1α (SDF-1α), which activates the cell-survival factor protein kinase B (PKB/Akt) via the G protein–coupled receptor CXCR4, protected tissue after an acute ischemic event in mice and activated Akt within endothelial cells and myocytes of the heart. Significantly better cardiac function than in control mice was evident as early as 24 hours after infarction as well as at 3, 14, and 28 days after infarction. Prolonged survival of hypoxic myocardium was followed by an increase in levels of vascular endothelial growth factor protein and neoangiogenesis. Consistent with improved cardiac function, mice exposed to SDF-1α demonstrated significantly decreased scar formation than control mice. Conclusion— These findings suggest that SDF-1α may serve a tissue-protective and regenerative role for solid organs suffering a hypoxic insult.
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