A DNA-binding Molecule Targeting the Adaptive Hypoxic Response in Multiple Myeloma has Potent Anti-tumor Activity

Multiple myeloma is incurable and invariably becomes resistant to chemotherapy. Although the mechanisms remain unclear, hypoxic conditions in the bone marrow have been implicated in contributing to multiple myeloma progression, angiogenesis, and resistance to chemotherapy. These effects occur via adaptive cellular responses mediated by hypoxia-inducible transcription factors (HIF), and targeting HIFs can have anticancer effects in both solid and hematologic malignancies. Here, it was found that in most myeloma cell lines tested, HIF1α, but not HIF2α expression was oxygen dependent, and this could be explained by the differential expression of the regulatory prolyl hydroxylase isoforms. The anti–multiple myeloma effects of a sequence-specific DNA-binding pyrrole-imidazole (Py-Im) polyamide (HIF-PA), which disrupts the HIF heterodimer from binding to its cognate DNA sequences, were also investigated. HIF-PA is cell permeable, localizes to the nuclei, and binds specific regions of DNA with an affinity comparable with that of HIFs. Most of the multiple myeloma cells were resistant to hypoxia-mediated apoptosis, and HIF-PA treatment could overcome this resistance in vitro. Using xenograft models, it was determined that HIF-PA significantly decreased tumor volume and increased hypoxic and apoptotic regions within solid tumor nodules and the growth of myeloma cells engrafted in the bone marrow. This provides a rationale for targeting the adaptive cellular hypoxic response of the O_2-dependent activation of HIFα using polyamides

An Assessment of Blood Vessel Remodeling of Nanofibrous Poly(ε-Caprolactone) Vascular Grafts in a Rat Animal Model

The development of an ideal vascular prosthesis represents an important challenge in terms of the treatment of cardiovascular diseases with respect to which new materials are being considered that have produced promising results following testing in animal models. This study focuses on nanofibrous polycaprolactone-based grafts assessed by means of histological techniques 10 days and 6 months following suturing as a replacement for the rat aorta. A novel stereological approach for the assessment of cellular distribution within the graft thickness was developed. The cellularization of the thickness of the graft was found to be homogeneous after 10 days and to have changed after 6 months, at which time the majority of cells was discovered in the inner layer where the regeneration of the vessel wall was found to have occurred. Six months following implantation, the endothelialization of the graft lumen was complete, and no vasa vasorum were found to be present. Newly formed tissue resembling native elastic arteries with concentric layers composed of smooth muscle cells, collagen, and elastin was found in the implanted polycaprolactone-based grafts. Moreover, the inner layer of the graft was seen to have developed structural similarities to the regular aortic wall. The grafts appeared to be well tolerated, and no severe adverse reaction was recorded with the exception of one case of cartilaginous metaplasia close to the junctional suture

Lifetime risk of atrial fibrillation according to optimal, borderline, or elevated levels of risk factors: cohort study based on longitudinal data from the Framingham Heart Study

OBJECTIVE: To examine the association between risk factor burdens-categorized as optimal, borderline, or elevated-and the lifetime risk of atrial fibrillation. DESIGN: Community based cohort study. SETTING: Longitudinal data from the Framingham Heart Study. PARTICIPANTS: Individuals free of atrial fibrillation at index ages 55, 65, and 75 years were assessed. Smoking, alcohol consumption, body mass index, blood pressure, diabetes, and history of heart failure or myocardial infarction were assessed as being optimal (that is, all risk factors were optimal), borderline (presence of borderline risk factors and absence of any elevated risk factor), or elevated (presence of at least one elevated risk factor) at index age. MAIN OUTCOME MEASURE: Lifetime risk of atrial fibrillation at index age up to 95 years, accounting for the competing risk of death. RESULTS: At index age 55 years, the study sample comprised 5338 participants (2531 (47.4%) men). In this group, 247 (4.6%) had an optimal risk profile, 1415 (26.5%) had a borderline risk profile, and 3676 (68.9%) an elevated risk profile. The prevalence of elevated risk factors increased gradually when the index ages rose. For index age of 55 years, the lifetime risk of atrial fibrillation was 37.0% (95% confidence interval 34.3% to 39.6%). The lifetime risk of atrial fibrillation was 23.4% (12.8% to 34.5%) with an optimal risk profile, 33.4% (27.9% to 38.9%) with a borderline risk profile, and 38.4% (35.5% to 41.4%) with an elevated risk profile. Overall, participants with at least one elevated risk factor were associated with at least 37.8% lifetime risk of atrial fibrillation. The gradient in lifetime risk across risk factor burden was similar at index ages 65 and 75 years. CONCLUSIONS: Regardless of index ages at 55, 65, or 75 years, an optimal risk factor profile was associated with a lifetime risk of atrial fibrillation of about one in five; this risk rose to more than one in three a third in individuals with at least one elevated risk factor

Colouration in amphibians as a reflection of nutritional status : the case of tree frogs in Costa Rica

Colouration has been considered a cue for mating success in many species; ornaments in males often are related to carotenoid mobilization towards feathers and/or skin and can signal general health and nutrition status. However, there are several factors that can also link with status, such as physiological blood parameters and body condition, but there is not substantial evidence which supports the existence of these relationships and interactions in anurans. This study evaluated how body score and blood values interact with colouration in free-range Agalychnis callidryas and Agalychnis annae males. We found significant associations between body condition and plasmatic proteins and haematocrit, as well as between body condition and colour values from the chromaticity diagram. We also demonstrated that there is a significant relation between the glucose and plasmatic protein values that were reflected in the ventral colours of the animals, and haematocrit inversely affected most of those colour values. Significant differences were found between species as well as between populations of A. callidryas, suggesting that despite colour variation, there are also biochemical differences within animals from the same species located in different regions. These data provide information on underlying factors for colouration of male tree frogs in nature, provide insights about the dynamics of several nutrients in the amphibian model and how this could affect the reproductive output of the animals

Regenerative peripheral nerve interfaces for real-time, proportional control of a Neuroprosthetic hand

Abstract Introduction Regenerative peripheral nerve interfaces (RPNIs) are biological constructs which amplify neural signals and have shown long-term stability in rat models. Real-time control of a neuroprosthesis in rat models has not yet been demonstrated. The purpose of this study was to: a) design and validate a system for translating electromyography (EMG) signals from an RPNI in a rat model into real-time control of a neuroprosthetic hand, and; b) use the system to demonstrate RPNI proportional neuroprosthesis control. Methods Animals were randomly assigned to three experimental groups: (1) Control; (2) Denervated, and; (3) RPNI. In the RPNI group, the extensor digitorum longus (EDL) muscle was dissected free, denervated, transferred to the lateral thigh and neurotized with the residual end of the transected common peroneal nerve. Rats received tactile stimuli to the hind-limb via monofilaments, and electrodes were used to record EMG. Signals were filtered, rectified and integrated using a moving sample window. Processed EMG signals (iEMG) from RPNIs were validated against Control and Denervated group outputs. Results Voluntary reflexive rat movements produced signaling that activated the prosthesis in both the Control and RPNI groups, but produced no activation in the Denervated group. Signal-to-Noise ratio between hind-limb movement and resting iEMG was 3.55 for Controls and 3.81 for RPNIs. Both Control and RPNI groups exhibited a logarithmic iEMG increase with increased monofilament pressure, allowing graded prosthetic hand speed control (R2 = 0.758 and R2 = 0.802, respectively). Conclusion EMG signals were successfully acquired from RPNIs and translated into real-time neuroprosthetic control. Signal contamination from muscles adjacent to the RPNI was minimal. RPNI constructs provided reliable proportional prosthetic hand control.https://deepblue.lib.umich.edu/bitstream/2027.42/146521/1/12984_2018_Article_452.pd

A facilitated home-based cardiac rehabilitation intervention for people with heart failure and their caregivers:a research programme including the REACH-HF RCT

Background: Rates of participation in centre (hospital)-cardiac rehabilitation by patients with heart failure are suboptimal. Heart failure has two main phenotypes differing in underlying pathophysiology: Heart failure with reduced ejection fraction is characterised by depressed left ventricular systolic function (‘reduced ejection fraction’), whereas heart failure with preserved ejection fraction is diagnosed after excluding other causes of dyspnoea with normal ejection fraction. This programme aimed to develop and evaluate a facilitated home-based cardiac rehabilitation intervention that could increase the uptake of cardiac rehabilitation while delivering the clinical benefits of centre-based cardiac rehabilitation. Objectives: To develop an evidence-informed, home-based, self-care cardiac rehabilitation programme for patients with heart failure and their caregivers [the REACH-HF (Rehabilitation Enablement in Chronic Heart Failure) intervention]. To conduct a pilot randomised controlled trial to assess the feasibility of a full trial of the clinical effectiveness and cost-effectiveness of the REACH-HF intervention in addition to usual care in patients with heart failure with preserved ejection fraction. To assess the short- and long-term clinical effectiveness and cost-effectiveness of the REACH-HF intervention in addition to usual care in patients with heart failure with reduced ejection fraction and their caregivers. Design: Intervention mapping to develop the REACH-HF intervention; uncontrolled feasibility study; pilot randomised controlled trial in those with heart failure with preserved ejection fraction; randomised controlled trial with a trial-based cost-effectiveness analysis in those with heart failure with reduced ejection fraction; qualitative studies including process evaluation; systematic review of cardiac rehabilitation in heart failure; and modelling to assess long-term cost-effectiveness (in those with heart failure with reduced ejection fraction). Setting: Four centres in England and Wales (Birmingham, Cornwall, Gwent and York); one centre in Scotland (Dundee) for a pilot randomised controlled trial. Participants: Adults aged ≥ 18 years with heart failure with reduced ejection fraction (left ventricular ejection fraction &lt; 45%) for the main randomised controlled trial (n = 216), and those with heart failure with preserved ejection fraction (left ventricular ejection fraction ≥ 45%) for the pilot randomised controlled trial (n = 50). Intervention: A self-care, facilitated cardiac rehabilitation manual was offered to patients (and participating caregivers) at home over 12 weeks by trained health-care professionals in addition to usual care or usual care alone. Main outcome measures: The primary outcome was disease-specific health-related quality of life measured using the Minnesota Living with Heart Failure Questionnaire at 12 months. Secondary outcomes included deaths and hospitalisations. Results: The main randomised controlled trial recruited 216 participants with heart failure with reduced ejection fraction and 97 caregivers. A significant and clinically meaningful between-group difference in the Minnesota Living with Heart Failure Questionnaire score (primary outcome) at 12 months (–5.7 points, 95% confidence interval –10.6 to –0.7 points) favoured the REACH-HF intervention (p = 0.025). Eight (4%) patients (four in each group) had died at 12 months. There was no significant difference in hospital admissions, at 12 months, with 19 participants in the REACH-HF intervention group having at least one hospital admission, compared with 24 participants in the control group (odds ratio 0.72, 95% confidence interval 0.35 to 1.51; p = 0.386). The mean cost of the intervention was £418 per participant with heart failure with reduced ejection fraction. The costs at 12 months were, on average, £401 higher in the intervention group than in the usual care alone group. Model-based economic evaluation, extrapolating from the main randomised controlled trial in those with heart failure with reduced ejection fraction over 4 years, found that adding the REACH-HF intervention to usual care had an estimated mean cost per participant of £15,452 (95% confidence interval £14,240 to £16,780) and a mean quality-adjusted lifeyear gain of 4.47 (95% confidence interval 3.83 to 4.91) years, compared with £15,051 (95% confidence interval £13,844 to £16,289) and 4.24 (95% confidence interval 4.05 to 4.43) years, respectively, for usual care alone. This gave an incremental cost per quality-adjusted life-year of £1721. The probabilistic sensitivity analysis indicated 78% probability that the intervention plus usual care versus usual care alone has a cost-effectiveness below the willingness-to-pay threshold of £20,000 per quality-adjusted life-year gained. The intervention was well received by participants with heart failure with reduced ejection fraction and those with heart failure with preserved ejection fraction, as well as their caregivers. Both randomised controlled trials recruited to target, with &gt; 85% retention at follow-up. Limitations: Key limitations included (1) lack of blinding – given the nature of the intervention and the control we could not mask participants to treatments, so our results may reflect participant expectation bias; (2) that we were not able to capture consistent participant-level data on level of intervention adherence; (3) that there may be an impact on the generalisability of findings due to the demographics of the trial patients, as most were male (78%) and we recruited only seven people from ethnic minorities. Conclusions: Evaluation of the comprehensive, facilitated, home-based REACH-HF intervention for participants with heart failure with reduced ejection fraction and caregivers indicated clinical effectiveness in terms of health-related quality of life and patient self-care but no other secondary outcomes. Although the economic analysis conducted alongside the full randomised controlled trial did not produce significant differences on the EuroQol-5 Dimensions or in quality-adjusted life-years, economic modelling suggested greater cost-effectiveness of the intervention than usual care. Our REACH-HF intervention offers a new evidence-based cardiac rehabilitation option that could increase uptake of cardiac rehabilitation in patients with heart failure not attracted to or able to access hospital-based programmes. Future work: Systematic collection of real-world data would track future changes in uptake of and adherence to alternative cardiac rehabilitation interventions in heart failure with reduced ejection fraction and increase understanding of how changes in service delivery might affect clinical and health economic outcomes. The findings of our pilot randomised controlled trial in patients with heart failure with preserved ejection fraction support progression to a full multicentre randomised controlled trial. </p

A facilitated home-based cardiac rehabilitation intervention for people with heart failure and their caregivers:a research programme including the REACH-HF RCT

Background: Rates of participation in centre (hospital)-cardiac rehabilitation by patients with heart failure are suboptimal. Heart failure has two main phenotypes differing in underlying pathophysiology: Heart failure with reduced ejection fraction is characterised by depressed left ventricular systolic function (‘reduced ejection fraction’), whereas heart failure with preserved ejection fraction is diagnosed after excluding other causes of dyspnoea with normal ejection fraction. This programme aimed to develop and evaluate a facilitated home-based cardiac rehabilitation intervention that could increase the uptake of cardiac rehabilitation while delivering the clinical benefits of centre-based cardiac rehabilitation. Objectives: To develop an evidence-informed, home-based, self-care cardiac rehabilitation programme for patients with heart failure and their caregivers [the REACH-HF (Rehabilitation Enablement in Chronic Heart Failure) intervention]. To conduct a pilot randomised controlled trial to assess the feasibility of a full trial of the clinical effectiveness and cost-effectiveness of the REACH-HF intervention in addition to usual care in patients with heart failure with preserved ejection fraction. To assess the short- and long-term clinical effectiveness and cost-effectiveness of the REACH-HF intervention in addition to usual care in patients with heart failure with reduced ejection fraction and their caregivers. Design: Intervention mapping to develop the REACH-HF intervention; uncontrolled feasibility study; pilot randomised controlled trial in those with heart failure with preserved ejection fraction; randomised controlled trial with a trial-based cost-effectiveness analysis in those with heart failure with reduced ejection fraction; qualitative studies including process evaluation; systematic review of cardiac rehabilitation in heart failure; and modelling to assess long-term cost-effectiveness (in those with heart failure with reduced ejection fraction). Setting: Four centres in England and Wales (Birmingham, Cornwall, Gwent and York); one centre in Scotland (Dundee) for a pilot randomised controlled trial. Participants: Adults aged ≥ 18 years with heart failure with reduced ejection fraction (left ventricular ejection fraction &lt; 45%) for the main randomised controlled trial (n = 216), and those with heart failure with preserved ejection fraction (left ventricular ejection fraction ≥ 45%) for the pilot randomised controlled trial (n = 50). Intervention: A self-care, facilitated cardiac rehabilitation manual was offered to patients (and participating caregivers) at home over 12 weeks by trained health-care professionals in addition to usual care or usual care alone. Main outcome measures: The primary outcome was disease-specific health-related quality of life measured using the Minnesota Living with Heart Failure Questionnaire at 12 months. Secondary outcomes included deaths and hospitalisations. Results: The main randomised controlled trial recruited 216 participants with heart failure with reduced ejection fraction and 97 caregivers. A significant and clinically meaningful between-group difference in the Minnesota Living with Heart Failure Questionnaire score (primary outcome) at 12 months (–5.7 points, 95% confidence interval –10.6 to –0.7 points) favoured the REACH-HF intervention (p = 0.025). Eight (4%) patients (four in each group) had died at 12 months. There was no significant difference in hospital admissions, at 12 months, with 19 participants in the REACH-HF intervention group having at least one hospital admission, compared with 24 participants in the control group (odds ratio 0.72, 95% confidence interval 0.35 to 1.51; p = 0.386). The mean cost of the intervention was £418 per participant with heart failure with reduced ejection fraction. The costs at 12 months were, on average, £401 higher in the intervention group than in the usual care alone group. Model-based economic evaluation, extrapolating from the main randomised controlled trial in those with heart failure with reduced ejection fraction over 4 years, found that adding the REACH-HF intervention to usual care had an estimated mean cost per participant of £15,452 (95% confidence interval £14,240 to £16,780) and a mean quality-adjusted lifeyear gain of 4.47 (95% confidence interval 3.83 to 4.91) years, compared with £15,051 (95% confidence interval £13,844 to £16,289) and 4.24 (95% confidence interval 4.05 to 4.43) years, respectively, for usual care alone. This gave an incremental cost per quality-adjusted life-year of £1721. The probabilistic sensitivity analysis indicated 78% probability that the intervention plus usual care versus usual care alone has a cost-effectiveness below the willingness-to-pay threshold of £20,000 per quality-adjusted life-year gained. The intervention was well received by participants with heart failure with reduced ejection fraction and those with heart failure with preserved ejection fraction, as well as their caregivers. Both randomised controlled trials recruited to target, with &gt; 85% retention at follow-up. Limitations: Key limitations included (1) lack of blinding – given the nature of the intervention and the control we could not mask participants to treatments, so our results may reflect participant expectation bias; (2) that we were not able to capture consistent participant-level data on level of intervention adherence; (3) that there may be an impact on the generalisability of findings due to the demographics of the trial patients, as most were male (78%) and we recruited only seven people from ethnic minorities. Conclusions: Evaluation of the comprehensive, facilitated, home-based REACH-HF intervention for participants with heart failure with reduced ejection fraction and caregivers indicated clinical effectiveness in terms of health-related quality of life and patient self-care but no other secondary outcomes. Although the economic analysis conducted alongside the full randomised controlled trial did not produce significant differences on the EuroQol-5 Dimensions or in quality-adjusted life-years, economic modelling suggested greater cost-effectiveness of the intervention than usual care. Our REACH-HF intervention offers a new evidence-based cardiac rehabilitation option that could increase uptake of cardiac rehabilitation in patients with heart failure not attracted to or able to access hospital-based programmes. Future work: Systematic collection of real-world data would track future changes in uptake of and adherence to alternative cardiac rehabilitation interventions in heart failure with reduced ejection fraction and increase understanding of how changes in service delivery might affect clinical and health economic outcomes. The findings of our pilot randomised controlled trial in patients with heart failure with preserved ejection fraction support progression to a full multicentre randomised controlled trial. </p

Distributed Dendritic Processing Facilitates Object Detection: A Computational Analysis on the Visual System of the Fly

Hennig P, Möller R, Egelhaaf M. Distributed Dendritic Processing Facilitates Object Detection: A Computational Analysis on the Visual System of the Fly. PLoS ONE. 2008;3(8): e3092.Background: Detecting objects is an important task when moving through a natural environment. Flies, for example, may land on salient objects or may avoid collisions with them. The neuronal ensemble of Figure Detection cells (FD-cells) in the visual system of the fly is likely to be involved in controlling these behaviours, as these cells are more sensitive to objects than to extended background structures. Until now the computations in the presynaptic neuronal network of FD-cells and, in particular, the functional significance of the experimentally established distributed dendritic processing of excitatory and inhibitory inputs is not understood. Methodology/Principal Findings: We use model simulations to analyse the neuronal computations responsible for the preference of FD-cells for small objects. We employed a new modelling approach which allowed us to account for the spatial spread of electrical signals in the dendrites while avoiding detailed compartmental modelling. The models are based on available physiological and anatomical data. Three models were tested each implementing an inhibitory neural circuit, but differing by the spatial arrangement of the inhibitory interaction. Parameter optimisation with an evolutionary algorithm revealed that only distributed dendritic processing satisfies the constraints arising from electrophysiological experiments. In contrast to a direct dendro-dendritic inhibition of the FD-cell (Direct Distributed Inhibition model), an inhibition of its presynaptic retinotopic elements (Indirect Distributed Inhibition model) requires smaller changes in input resistance in the inhibited neurons during visual stimulation. Conclusions/Significance: Distributed dendritic inhibition of retinotopic elements as implemented in our Indirect Distributed Inhibition model is the most plausible wiring scheme for the neuronal circuit of FD-cells. This microcircuit is computationally similar to lateral inhibition between the retinotopic elements. Hence, distributed inhibition might be an alternative explanation of perceptual phenomena currently explained by lateral inhibition networks

MicroRNAs in pulmonary arterial remodeling

Pulmonary arterial remodeling is a presently irreversible pathologic hallmark of pulmonary arterial hypertension (PAH). This complex disease involves pathogenic dysregulation of all cell types within the small pulmonary arteries contributing to vascular remodeling leading to intimal lesions, resulting in elevated pulmonary vascular resistance and right heart dysfunction. Mutations within the bone morphogenetic protein receptor 2 gene, leading to dysregulated proliferation of pulmonary artery smooth muscle cells, have been identified as being responsible for heritable PAH. Indeed, the disease is characterized by excessive cellular proliferation and resistance to apoptosis of smooth muscle and endothelial cells. Significant gene dysregulation at the transcriptional and signaling level has been identified. MicroRNAs are small non-coding RNA molecules that negatively regulate gene expression and have the ability to target numerous genes, therefore potentially controlling a host of gene regulatory and signaling pathways. The major role of miRNAs in pulmonary arterial remodeling is still relatively unknown although research data is emerging apace. Modulation of miRNAs represents a possible therapeutic target for altering the remodeling phenotype in the pulmonary vasculature. This review will focus on the role of miRNAs in regulating smooth muscle and endothelial cell phenotypes and their influence on pulmonary remodeling in the setting of PAH