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1.
Circ Res ; 134(10): 1306-1326, 2024 May 10.
Article in English | MEDLINE | ID: mdl-38533639

ABSTRACT

BACKGROUND: Ventricular arrhythmias (VAs) demonstrate a prominent day-night rhythm, commonly presenting in the morning. Transcriptional rhythms in cardiac ion channels accompany this phenomenon, but their role in the morning vulnerability to VAs and the underlying mechanisms are not understood. We investigated the recruitment of transcription factors that underpins transcriptional rhythms in ion channels and assessed whether this mechanism was pertinent to the heart's intrinsic diurnal susceptibility to VA. METHODS AND RESULTS: Assay for transposase-accessible chromatin with sequencing performed in mouse ventricular myocyte nuclei at the beginning of the animals' inactive (ZT0) and active (ZT12) periods revealed differentially accessible chromatin sites annotating to rhythmically transcribed ion channels and distinct transcription factor binding motifs in these regions. Notably, motif enrichment for the glucocorticoid receptor (GR; transcriptional effector of corticosteroid signaling) in open chromatin profiles at ZT12 was observed, in line with the well-recognized ZT12 peak in circulating corticosteroids. Molecular, electrophysiological, and in silico biophysically-detailed modeling approaches demonstrated GR-mediated transcriptional control of ion channels (including Scn5a underlying the cardiac Na+ current, Kcnh2 underlying the rapid delayed rectifier K+ current, and Gja1 responsible for electrical coupling) and their contribution to the day-night rhythm in the vulnerability to VA. Strikingly, both pharmacological block of GR and cardiomyocyte-specific genetic knockout of GR blunted or abolished ion channel expression rhythms and abolished the ZT12 susceptibility to pacing-induced VA in isolated hearts. CONCLUSIONS: Our study registers a day-night rhythm in chromatin accessibility that accompanies diurnal cycles in ventricular myocytes. Our approaches directly implicate the cardiac GR in the myocyte excitability rhythm and mechanistically link the ZT12 surge in glucocorticoids to intrinsic VA propensity at this time.


Subject(s)
Circadian Rhythm , Myocytes, Cardiac , Receptors, Glucocorticoid , Animals , Receptors, Glucocorticoid/metabolism , Receptors, Glucocorticoid/genetics , Mice , Myocytes, Cardiac/metabolism , Male , Arrhythmias, Cardiac/metabolism , Arrhythmias, Cardiac/physiopathology , Arrhythmias, Cardiac/genetics , Mice, Inbred C57BL , NAV1.5 Voltage-Gated Sodium Channel/metabolism , NAV1.5 Voltage-Gated Sodium Channel/genetics , Connexin 43/metabolism , Connexin 43/genetics , Mice, Knockout , Action Potentials
2.
Am J Physiol Renal Physiol ; 327(1): F113-F127, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38660712

ABSTRACT

The kidneys maintain fluid-electrolyte balance and excrete waste in the presence of constant fluctuations in plasma volume and systemic blood pressure. The kidneys perform these functions to control capillary perfusion and glomerular filtration by modulating the mechanisms of autoregulation. An effect of these modulations are spontaneous, natural fluctuations in glomerular perfusion. Numerous other mechanisms can lead to fluctuations in perfusion and flow. The ability to monitor these spontaneous physiological fluctuations in vivo could facilitate the early detection of kidney disease. The goal of this work was to investigate the use of resting-state magnetic resonance imaging (rsMRI) to detect spontaneous physiological fluctuations in the kidney. We performed rsMRI of rat kidneys in vivo over 10 min, applying motion correction to resolve time series in each voxel. We observed spatially variable, spontaneous fluctuations in rsMRI signal between 0 and 0.3 Hz, in frequency bands associated with autoregulatory mechanisms. We further applied rsMRI to investigate changes in these fluctuations in a rat model of diabetic nephropathy. Spectral analysis was performed on time series of rsMRI signals in the kidney cortex and medulla. The power from spectra in specific frequency bands from the cortex correlated with severity of glomerular pathology caused by diabetic nephropathy. Finally, we investigated the feasibility of using rsMRI of the human kidney in two participants, observing the presence of similar, spatially variable fluctuations. This approach may enable a range of preclinical and clinical investigations of kidney function and facilitate the development of new therapies to improve outcomes in patients with kidney disease.NEW & NOTEWORTHY This work demonstrates the development and use of resting-state MRI to detect low-frequency, spontaneous physiological fluctuations in the kidney consistent with previously observed fluctuations in perfusion and potentially due to autoregulatory function. These fluctuations are detectable in rat and human kidneys, and the power of these fluctuations is affected by diabetic nephropathy in rats.


Subject(s)
Diabetic Nephropathies , Kidney , Magnetic Resonance Imaging , Rats, Sprague-Dawley , Animals , Diabetic Nephropathies/physiopathology , Diabetic Nephropathies/diagnostic imaging , Magnetic Resonance Imaging/methods , Male , Kidney/physiopathology , Kidney/diagnostic imaging , Rats , Diabetes Mellitus, Experimental/physiopathology , Diabetes Mellitus, Experimental/diagnostic imaging , Renal Circulation , Humans , Homeostasis/physiology
3.
Pain Med ; 24(8): 963-973, 2023 08 01.
Article in English | MEDLINE | ID: mdl-36975607

ABSTRACT

OBJECTIVE: We developed and used a discrete-choice measure to study patient preferences with regard to the risks and benefits of nonsurgical treatments when they are making treatment selections for chronic low back pain. METHODS: "CAPER TREATMENT" (Leslie Wilson) was developed with standard choice-based conjoint procedures (discrete-choice methodology that mimics an individual's decision-making process). After expert input and pilot testing, our final measure had 7 attributes (chance of pain relief, duration of relief, physical activity changes, treatment method, treatment type, treatment time burden, and risks of treatment) with 3-4 levels each. Using Sawtooth software (Sawtooth Software, Inc., Provo, UT, USA), we created a random, full-profile, balanced-overlap experimental design. Respondents (n = 211) were recruited via an emailed online link and completed 14 choice-based conjoint choice pairs; 2 fixed questions; and demographic, clinical, and quality-of-life questions. Analysis was performed with random-parameters multinomial logit with 1000 Halton draws. RESULTS: Patients cared most about the chance of pain relief, followed closely by improving physical activity, even more than duration of pain relief. There was comparatively less concern about time commitment and risks. Gender and socioeconomic status influenced preferences, especially with relation to strength of expectations for outcomes. Patients experiencing a low level of pain (Pain, Enjoyment, and General Activity Scale [PEG], question 1, numeric rating scale score<4) had a stronger desire for maximally improved physical activity, whereas those in a high level of pain (PEG, question 1, numeric rating scale score>6) preferred both maximum and more limited activity. Highly disabled patients (Oswestry Disability Index score>40) demonstrated distinctly different preferences, placing more weight on achieving pain control and less on improving physical activity. CONCLUSIONS: Individuals with chronic low back pain were willing to trade risks and inconveniences for better pain control and physical activity. Additionally, different preference phenotypes exist, which suggests a need for clinicians to target treatments to particular patients.


Subject(s)
Low Back Pain , Humans , Low Back Pain/therapy , Choice Behavior , Patient Preference , Pain Management
4.
Exp Eye Res ; 223: 109198, 2022 10.
Article in English | MEDLINE | ID: mdl-35921962

ABSTRACT

Post-infectious uveitis describes the condition of chronic immune mediated ocular inflammation associated with pathogens such as Mycobacterium tuberculosis (Mtb). Mtb associated post-infectious uveitis can be modeled in mice by intravitreal injection of heat-killed Mtb (HKMtb). To better understand how prior systemic exposure to the pathogen alters the local immune response to Mtb, we used flow cytometry and multiplex ELISAs to compare ocular responses to intravitreal HKMtb in the presence or absence of a systemic "prime" of HKMtb. Priming resulted in exacerbation of local inflammation with significantly increased clinical and histologic inflammation scores and increased vitreous cytokines concentrations one day after intravitreal injection of HKMtb. Seven days after injection, uveitis in unprimed animals had largely resolved. In contrast in primed animals, clinical signs of chronic inflammation were associated with a significant increase in the number of ocular T cells, NK cells, and Ly6Chi macrophages and increasing vitreous concentrations of IL-17, VEGF, MIG(CXCL9), IP-10(CXCL10), IL-12p40 and MIP-1α(CCL3). In mice lacking mature T and B cells (RAG2 deficient), the impact of priming on the ocular immune response was ameliorated with significantly lower vitreous cytokine concentrations and spontaneous resolution of uveitis. Altogether these results suggest that the ocular response to Mtb is exacerbated by prior systemic Mtb infection and chronic post-infectious uveitis is mediated by local production of cytokines and chemokines that amplify Th17 and Th1 responses. This mouse model of chronic Mtb associated uveitis will help elucidate mechanisms of disease in patients with post-infectious uveitis.


Subject(s)
Mycobacterium tuberculosis , Uveitis , Animals , Chemokine CCL3 , Chemokine CXCL10 , Cytokines , Hot Temperature , Immunity , Inflammation , Interleukin-12 Subunit p40 , Interleukin-17 , Mice , Vascular Endothelial Growth Factor A
5.
Eur J Cancer Care (Engl) ; 31(6): e13740, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36239065

ABSTRACT

OBJECTIVE: We evaluate cost-effectiveness of primary treatments for localised prostate cancer by uniquely combining prospectively collected real-world outcomes and costs from UCSF Cancer of Prostate Strategic Urologic Research Endeavor (CaPSURE™). METHODS: Markov models assessed cost-effectiveness of radical prostatectomy (RP), brachytherapy, electron beam radiation therapy (EBRT) and brachytherapy with EBRT by risk from US payers perspective over 8 years. Treatment costs included office visits, hospitalisation, procedures, medication and long-term care. Patients' surveyed HRQoL were mapped into utilities. Incremental cost-effectiveness ratios (ICERs) used cost per quality-adjusted life years (QALYs) and willingness-to-pay of $150,000/QALY. RESULTS: Cost-effectiveness analysis (CEA) showed for low-risk prostate cancer, EBRT dominated the lowest cost brachytherapy, but RPns and brachytherapy plus EBRT were cost-effective compared to brachytherapy with ICERs of $18,926 and $41,662 per QALY. In medium-risk patients, RP, EBRT and brachytherapy plus EBRT all were cost-effective compared with brachytherapy, with ICERs of $30,604, $22,588 and $21,627/QALY. In high-risk, brachytherapy dominated all treatments. Procedure cost and utility are driving ICER, but probabilistic sensitivity analysis showed the model was robust across variables. CONCLUSION: This first CEA combining prospective real-world evidence for HRQOL outcomes with costs shows cost-effectiveness of treatments vary by risk groups, providing new evidence for treatment decisions.


Subject(s)
Prostatic Neoplasms , Male , Humans , Cost-Benefit Analysis , Prospective Studies , Prostatic Neoplasms/therapy , Quality-Adjusted Life Years , Prostatectomy
6.
Toxicol Appl Pharmacol ; 421: 115534, 2021 06 15.
Article in English | MEDLINE | ID: mdl-33852878

ABSTRACT

Monomethyl auristatin E (MMAE) is a potent anti-cancer microtubule-targeting agent (MTA) used as a payload in three approved MMAE-containing antibody drug conjugates (ADCs) and multiple ADCs in clinical development to treat different types of cancers. Unfortunately, MMAE-ADCs can induce peripheral neuropathy, a frequent adverse event leading to treatment dose reduction or discontinuation and subsequent clinical termination of many MMAE-ADCs. MMAE-ADC-induced peripheral neuropathy is attributed to non-specific uptake of the ADC in peripheral nerves and release of MMAE, disrupting microtubules (MTs) and causing neurodegeneration. However, molecular mechanisms underlying MMAE and MMAE-ADC effects on MTs remain unclear. Here, we characterized MMAE-tubulin/MT interactions in reconstituted in vitro soluble tubulin or MT systems and evaluated MMAE and vcMMAE-ADCs in cultured human MCF7 cells. MMAE bound to soluble tubulin heterodimers with a maximum stoichiometry of ~1:1, bound abundantly along the length of pre-assembled MTs and with high affinity at MT ends, introduced structural defects, suppressed MT dynamics, and reduced the kinetics and extent of MT assembly while promoting tubulin ring formation. In cells, MMAE and MMAE-ADC (via nonspecific uptake) suppressed proliferation, mitosis and MT dynamics, and disrupted the MT network. Comparing MMAE action to other MTAs supports the hypothesis that peripheral neuropathy severity is determined by the precise mechanism(s) of each individual drug-MT interaction (location of binding, affinity, effects on morphology and dynamics). This work demonstrates that MMAE binds extensively to tubulin and MTs and causes severe MT dysregulation, providing convincing evidence that MMAE-mediated inhibition of MT-dependent axonal transport leads to severe peripheral neuropathy.


Subject(s)
Breast Neoplasms/drug therapy , Microtubules/drug effects , Oligopeptides/toxicity , Peripheral Nervous System Diseases/chemically induced , Peripheral Nervous System/drug effects , Tubulin Modulators/toxicity , Tubulin/metabolism , Axonal Transport/drug effects , Binding Sites , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Cell Cycle/drug effects , Cell Proliferation/drug effects , Female , Humans , MCF-7 Cells , Microtubules/metabolism , Microtubules/pathology , Mitosis/drug effects , Oligopeptides/metabolism , Peripheral Nervous System/metabolism , Peripheral Nervous System/pathology , Peripheral Nervous System Diseases/metabolism , Peripheral Nervous System Diseases/pathology , Protein Binding , Risk Assessment , Spindle Apparatus/drug effects , Spindle Apparatus/metabolism , Spindle Apparatus/pathology , Tubulin Modulators/metabolism
7.
J Biol Chem ; 294(33): 12265-12280, 2019 08 16.
Article in English | MEDLINE | ID: mdl-31266806

ABSTRACT

The microtubule (MT)-associated protein tau regulates the critical growing and shortening behaviors of MTs, and its normal activity is essential for neuronal development and maintenance. Accordingly, aberrant tau action is tightly associated with Alzheimer's disease and is genetically linked to several additional neurodegenerative diseases known as tauopathies. Although tau is known to promote net MT growth and stability, the precise mechanistic details governing its regulation of MT dynamics remain unclear. Here, we have used the slowly-hydrolyzable GTP analog, guanylyl-(α,ß)-methylene-diphosphonate (GMPCPP), to examine the structural effects of tau at MT ends that may otherwise be too transient to observe. The addition of both four-repeat (4R) and three-repeat (3R) tau isoforms to pre-formed GMPCPP MTs resulted in the formation of extended, multiprotofilament-wide projections at MT ends. Furthermore, at temperatures too low for assembly of bona fide MTs, both tau isoforms promoted the formation of long spiral ribbons from GMPCPP tubulin heterodimers. In addition, GMPCPP MTs undergoing cold-induced disassembly in the presence of 4R tau (and to a much lesser extent 3R tau) also formed spirals. Finally, three pathological tau mutations known to cause neurodegeneration and dementia were differentially compromised in their abilities to stabilize MT disassembly intermediates. Taken together, we propose that tau promotes the formation/stabilization of intermediate states in MT assembly and disassembly by promoting both longitudinal and lateral tubulin-tubulin contacts. We hypothesize that these activities represent fundamental aspects of tau action that normally occur at the GTP-rich ends of GTP/GDP MTs and that may be compromised in neurodegeneration-causing tau variants.


Subject(s)
Microtubules/chemistry , Tubulin/chemistry , tau Proteins/chemistry , Dementia/metabolism , Humans , Microtubules/genetics , Microtubules/metabolism , Mutation , Neurodegenerative Diseases/genetics , Neurodegenerative Diseases/metabolism , Protein Isoforms/chemistry , Protein Isoforms/genetics , Protein Isoforms/metabolism , Tubulin/genetics , Tubulin/metabolism , tau Proteins/genetics , tau Proteins/metabolism
8.
Small ; 16(37): e2001240, 2020 09.
Article in English | MEDLINE | ID: mdl-32794304

ABSTRACT

By virtue of their native structures, tubulin dimers are protein building blocks that are naturally preprogrammed to assemble into microtubules (MTs), which are cytoskeletal polymers. Here, polycation-directed (i.e., electrostatically tunable) assembly of tubulins is demonstrated by conformational changes to the tubulin protofilament in longitudinal and lateral directions, creating tubulin double helices and various tubular architectures. Synchrotron small-angle X-ray scattering and transmission electron microscopy reveal a remarkable range of nanoscale assembly structures: single- and double-layered double-helix tubulin tubules. The phase transitions from MTs to the new assemblies are dependent on the size and concentration of polycations. Two characteristic scales that determine the number of observed phases are the size of polycation compared to the size of tubulin (≈4 nm) and to MT diameter (≈25 nm). This work suggests the feasibility of using polycations that have scissor- and glue-like properties to achieve "programmable breakdown" of protein nanotubes, tearing MTs into double-stranded tubulins and building up previously undiscovered nanostructures. Importantly, a new role of tubulins is defined as 2D shape-controllable building blocks for supramolecular architectures. These findings provide insight into the design of protein-based functional materials, for example, as metallization templates for nanoscale electronic devices, molecular screws, and drug delivery vehicles.


Subject(s)
Microtubules , Tubulin , Cytoskeleton , Polymers
9.
J Cardiovasc Electrophysiol ; 31(7): 1672-1677, 2020 07.
Article in English | MEDLINE | ID: mdl-32298025

ABSTRACT

INTRODUCTION: Transseptal puncture is an integral step in various catheter-based cardiac procedures and can be performed with either the conventional mechanical needle or an FDA-cleared device utilizing radiofrequency (RF) energy. Although a previous randomized trial suggested that the RF transseptal device may be faster and more often successful, the increased equipment costs may dissuade operators from routine use. This analysis compares the cost-effectiveness of the mechanical needle to the RF device during pulmonary vein isolation. METHODS: The rates of successful transseptal punctures for each device and transseptal-related complications were determined from the peer-reviewed medical literature. Procedural, equipment, and complication costs were obtained from peer-reviewed medical literature and the Healthcare Cost and Utilization Project. The effectiveness was defined as the probability of 30-day survival following a successful transseptal puncture. Monte Carlo probabilistic analyses tested variable effects of costs and complication rates on the incremental cost-effectiveness ratio. RESULTS: The 30-day effectiveness of the RF device vs the mechanical needle was 99.7% and 98.8%, respectively. After accounting for all costs of performing a single transseptal puncture, the cost at 30 days associated with the RF device was $41 less than the mechanical needle ($21 096 vs $21 137). The RF device was similarly dominant to the mechanical needle in double transseptal puncture scenarios. Finally, the RF device was more cost-effective than the mechanical needle at any willingness-to-pay in Monte Carlo probabilistic sensitivity analyses. CONCLUSIONS: Despite greater equipment costs, the RF device costs less and provides better effectiveness at 30 days than the conventional mechanical needle.


Subject(s)
Atrial Fibrillation , Catheter Ablation , Atrial Fibrillation/diagnosis , Atrial Fibrillation/surgery , Catheter Ablation/adverse effects , Cost-Benefit Analysis , Humans , Needles , Punctures , Treatment Outcome
10.
Vet Dermatol ; 31(4): 317-e80, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32249514

ABSTRACT

BACKGROUND: Cutaneous histiocytomas (CH) are derived from epidermal Langerhans cells. Single CH are generally associated with a good prognosis in dogs because most undergo spontaneous remission. However, aggressive behaviour and lymph node metastasis have been reported in a small number of dogs with single CH. OBJECTIVE: To describe the clinical presentation, treatment and disease progression of an aggressive CH located in the ear canal of a dog. ANIMAL: An 8-year-old intact male Rottweiler dog. METHODS AND MATERIALS: A unilateral ear canal mass was identified as a CH on routine haematoxylin and eosin stained samples. The diagnosis was confirmed by the demonstration of markers associated with Langerhans cells (Iba-1, E-cadherin and CD18) and the absence of markers associated with B cells (CD79a, CD20, Pax5), T cells (CD3), plasma cells (Mum-1) and macrophages (CD11d, CD204). RESULTS: A total ear canal ablation was performed, but tumour cells extended throughout the horizontal canal and to the deep surgical margin. Due to the locally invasive nature of the mass and incomplete excision, adjunctive chemotherapy with CCNU was pursued. No measurable local disease was appreciable at the time of the last treatment. At 250 days post-surgery the dog was euthanized owing to the development of multiple abdominal masses. No evidence of local tumour recurrence was noted. CONCLUSIONS AND CLINICAL IMPORTANCE: Although single CH are typically associated with benign behaviour, the mass in this dog demonstrated locally invasive behaviour. Cutaneous histiocytomas in the ear canals of dogs may represent a particularly aggressive variant of the condition.


Subject(s)
Dog Diseases/diagnosis , Ear Canal/pathology , Ear Neoplasms/veterinary , Histiocytoma/veterinary , Skin/pathology , Tomography, X-Ray Computed/veterinary , Animals , Disease Progression , Dogs , Ear Neoplasms/diagnostic imaging , Ear Neoplasms/pathology , Euthanasia, Animal , Head/diagnostic imaging , Histiocytoma/diagnostic imaging , Histiocytoma/pathology , Male , Neoplasm Metastasis
11.
Langmuir ; 35(48): 15970-15978, 2019 12 03.
Article in English | MEDLINE | ID: mdl-31539262

ABSTRACT

In this minireview, which is part of a special issue in honor of Jacob N. Israelachvili's remarkable research career on intermolecular forces and interfacial science, we present studies of structures, phase behavior, and forces in reaction mixtures of microtubules (MTs) and tubulin oligomers with either intrinsically disordered protein (IDP) Tau, cationic vesicles, or the polyamine spermine (4+). Bare MTs consist of 13 protofilaments (PFs), on average, where each PF is made of a linear stack of αß-tubulin dimers (i.e., tubulin oligomers). We begin with a series of experiments which demonstrate the flexibility of PFs toward shape changes in response to local environmental cues. First, studies show that MT-associated protein (MAP) Tau controls the diameter of microtubules upon binding to the outer surface, implying a shape change in the cross-sectional area of PFs forming the MT perimeter. The diameter of a MT may also be controlled by the charge density of a lipid bilayer membrane that coats the outer surface. We further describe an experimental study where it is unexpectedly found that the biologically relevant polyamine spermine (+4e) is able to depolymerize taxol-stabilized microtubules with efficiency that increases with decreasing temperature. This MT destabilization drives a dynamical structural transition where inside-out curving of PFs, during the depolymerization peeling process, is followed by reassembly of ring-like curved PF building blocks into an array of helical inverted tubulin tubules. We finally turn to a very recent study on pressure-distance measurements in bundles of MTs employing the small-angle X-ray scattering (SAXS)-osmotic pressure technique, which complements the surface-forces-apparatus technique developed by Jacob N. Israelachvili. These latter studies are among the very few which are beginning to shed light on the precise nature of the interactions between MTs mediated by MAP Tau in 37 °C reaction mixtures containing GTP and lacking taxol.


Subject(s)
Biopolymers/chemistry , Intrinsically Disordered Proteins/chemistry , Microtubules/chemistry , Tubulin/chemistry , tau Proteins/chemistry , Cations , Paclitaxel/chemistry , Protein Conformation
12.
BMC Med Inform Decis Mak ; 19(1): 6, 2019 01 09.
Article in English | MEDLINE | ID: mdl-30626400

ABSTRACT

BACKGROUND: The Personal Patient Profile-Prostate (P3P) is a web-based decision support system for men newly diagnosed with localized prostate cancer that has demonstrated efficacy in reducing decisional conflict. Our objective was to estimate willingness-to-pay (WTP) for men's decisional preparation activities. METHODS: In a multicenter, randomized trial of P3P, usual care group participants received typical preparation for decision making plus referral to publicly-available, educational websites. Intervention group participants received the same, plus online P3P educational media specific to the user's personal preferences and values, and a communication coaching component tailored to race\ethnicity, age and language. WTP data were collected one week after physician consultation. An iterative bidding direct contingent valuation survey format was used, randomly assigning participants to high or low starting values (SV). Tobit models were used to explore associations between SV-adjusted WTP and age, education, marital and work-status, insurance, decision-control preference and decision-making stage. RESULTS: Of 392 participants enrolled, 141 P3P and 107 usual care (UC) provided a WTP value. Men were willing to pay a median $25 (IQR $10-100) for P3P in addition to usual care preparation materials. In the final multivariable tobit regression model, SV, marital status, stage of decision making and income were significantly associated with WTP for P3P. Decision control preference was considered marginally significant (p = 0.11). Men were WTP a median $30 (IQR $10-$200) for usual care material alone. In the final multivariable model, SV, education, and stage of decision making were significantly associated with WTP in usual care. CONCLUSION: WTP was similar for UC and for the addition of P3P to UC decision preparation. The WTP values were associated with demographic and preference variables. Findings can help focus decision support on future patients who would benefit most: those without strong support systems, at earlier stages of decision making, and open to a shared-decision style. TRIAL REGISTRATION: NCT NCT01844999 . Registered May 3, 2013.


Subject(s)
Decision Making , Decision Support Techniques , Patient Acceptance of Health Care , Patient Education as Topic , Prostatic Neoplasms , Aged , Humans , Male , Middle Aged , Prostatic Neoplasms/economics
13.
Alzheimers Dement ; 15(7): 899-906, 2019 07.
Article in English | MEDLINE | ID: mdl-31175026

ABSTRACT

INTRODUCTION: Dementia is among the costliest of medical conditions, but it is not known how these costs vary by dementia subtype. METHODS: The effect of dementia diagnosis subtype on direct health care costs and utilization was estimated using 2015 California Medicare fee-for-service data. Potential drivers of increased costs in Lewy body dementia (LBD), in comparison to Alzheimer's disease, were tested. RESULTS: 3,001,987 Medicare beneficiaries were identified, of which 8.2% had a dementia diagnosis. Unspecified dementia was the most common diagnostic category (59.6%), followed by Alzheimer's disease (23.2%). LBD was the costliest subtype to Medicare, on average, followed by vascular dementia. The higher costs in LBD were explained in part by falls, urinary incontinence or infection, depression, anxiety, dehydration, and delirium. DISCUSSION: Dementia subtype is an important predictor of health care costs. Earlier identification and targeted treatment might mitigate the costs associated with co-occurring conditions in LBD.


Subject(s)
Dementia , Fee-for-Service Plans/economics , Health Care Costs , Health Services for the Aged/statistics & numerical data , Medicare/economics , Aged , Aged, 80 and over , California , Dementia/classification , Dementia/economics , Dementia, Vascular , Female , Health Services for the Aged/economics , Humans , Lewy Body Disease/economics , Male , United States
14.
Clin Infect Dis ; 67(5): 751-759, 2018 08 16.
Article in English | MEDLINE | ID: mdl-29474546

ABSTRACT

Background: Text messaging is a promising strategy to support human immunodeficiency virus (HIV) care engagement, but little is known about its efficacy in urban safety-net HIV clinics. Methods: We conducted a randomized controlled trial of a supportive and motivational text messaging intervention, Connect4Care (C4C), among viremic patients who had a history of poor retention or were new to the clinic. Participants were randomized (stratified by new or established HIV diagnosis status) to receive either of the following for 12 months: (1) thrice-weekly intervention messages, plus texted primary care appointment reminders and a monthly text message requesting confirmation of study participation or (2) texted reminders and monthly messages alone. Viral load was assessed at 6 and 12 months. The primary outcome was virologic suppression (<200 copies/mL) at 12 months, estimated via repeated-measures log-binomial regression, adjusted for new-diagnosis status. The secondary outcome was retention in clinic care. Results: Between August 2013 and November 2015, a total of 230 participants were randomized. Virologic suppression at 12 months was similar in intervention and control participants (48.8% vs 45.8%, respectively), yielding a rate ratio of 1.07 (95% confidence interval, .82-1.39). Suppression was higher in those with newly diagnosed infection (78.3% vs 45.3%). There were no intervention effects on the secondary outcome. Exploratory analyses suggested that patients with more responses to study text messages had better outcomes, regardless of arm. Conclusions: The C4C text messaging intervention did not significantly increase virologic suppression or retention in care. Response to text messages may be a useful way for providers to gauge risk for poor HIV outcomes. Clinical Trials Registration: NCT01917994.


Subject(s)
Appointments and Schedules , HIV Infections/therapy , Retention in Care , Sustained Virologic Response , Text Messaging , Adult , Aged , Ambulatory Care Facilities , Cell Phone , Early Medical Intervention , Female , Humans , Male , Middle Aged , Motivation , Research Design , San Francisco , Urban Population , Viral Load , Viremia/prevention & control , Young Adult
15.
Anal Chem ; 90(1): 888-895, 2018 01 02.
Article in English | MEDLINE | ID: mdl-29191006

ABSTRACT

Hydrogen peroxide (H2O2) is an endogenous molecule that plays several important roles in brain function: it is generated in cellular respiration, serves as a modulator of dopaminergic signaling, and its presence can indicate the upstream production of more aggressive reactive oxygen species (ROS). H2O2 has been implicated in several neurodegenerative diseases, including Parkinson's disease (PD), creating a critical need to identify mechanisms by which H2O2 modulates cellular processes in general and how it affects the dopaminergic nigrostriatal pathway, in particular. Furthermore, there is broad interest in selective electrochemical quantification of H2O2, because it is often enzymatically generated at biosensors as a reporter for the presence of nonelectroactive target molecules. H2O2 fluctuations can be monitored in real time using fast-scan cyclic voltammetry (FSCV) coupled with carbon-fiber microelectrodes. However, selective identification is a critical issue when working in the presence of other molecules that generate similar voltammograms, such as adenosine and histamine. We have addressed this problem by fabricating a robust, H2O2-selective electrode. 1,3-Phenylenediamine (mPD) was electrodeposited on a carbon-fiber microelectrode to create a size-exclusion membrane, rendering the electrode sensitive to H2O2 fluctuations and pH shifts but not to other commonly studied neurochemicals. The electrodes are described and characterized herein. The data demonstrate that this technology can be used to ensure the selective detection of H2O2, enabling confident characterization of the role this molecule plays in normal physiological function as well as in the progression of PD and other neuropathies involving oxidative stress.


Subject(s)
Carbon/chemistry , Electrochemical Techniques/instrumentation , Hydrogen Peroxide/analysis , Phenylenediamines/chemistry , Animals , Corpus Striatum/metabolism , Electrochemical Techniques/methods , Male , Microelectrodes , Rats, Sprague-Dawley
16.
J Urol ; 199(1): 89-97, 2018 01.
Article in English | MEDLINE | ID: mdl-28754540

ABSTRACT

PURPOSE: We evaluated the efficacy of the web based P3P (Personal Patient Profile-Prostate) decision aid vs usual care with regard to decisional conflict in men with localized prostate cancer. MATERIALS AND METHODS: A randomized (1:1), controlled, parallel group, nonblinded trial was performed in 4 regions of the United States. Eligible men had clinically localized prostate cancer and an upcoming consultation, and they spoke and read English or Spanish. Participants answered questionnaires to report decision making stage, personal characteristics, concerns and preferences plus baseline symptoms and decisional conflict. A randomization algorithm allocated participants to receive tailored education and communication coaching, generic teaching sheets and external websites plus a 1-page summary to clinicians (intervention) or the links plus materials provided in clinic (usual care). Conflict outcomes and the number of consultations were measured at 1 month. Univariate and multivariable models were used to analyze outcomes. RESULTS: A total of 392 men were randomized, including 198 to intervention and 194 to usual care, of whom 152 and 153, respectively, returned 1-month outcomes. The mean ± SD 1-month decisional conflict scale (score range 0 to 100) was 10.9 ± 16.7 for intervention and 9.9 ± 18.0 for usual care. The multivariable model revealed significantly reduced conflict in the intervention group (-5.00, 95% CI -9.40--0.59). Other predictors of conflict included income, marital or partner status, decision status, number of consultations, clinical site and D'Amico risk classification. CONCLUSIONS: In this multicenter trial the decision aid significantly reduced decisional conflict. Other variables impacted conflict and modified the effect of the decision aid, notably risk classification, consultations and resources. P3P is an effective adjunct for shared decision making in men with localized prostate cancer.


Subject(s)
Decision Support Techniques , Internet , Prostatic Neoplasms/therapy , Adult , Aged , Algorithms , Biopsy , Demography , Humans , Male , Middle Aged , Prostatic Neoplasms/pathology , Surveys and Questionnaires , United States
17.
Proc Natl Acad Sci U S A ; 112(47): E6416-25, 2015 Nov 24.
Article in English | MEDLINE | ID: mdl-26542680

ABSTRACT

Microtubules (MTs) are hollow cytoskeletal filaments assembled from αß-tubulin heterodimers. Tau, an unstructured protein found in neuronal axons, binds to MTs and regulates their dynamics. Aberrant Tau behavior is associated with neurodegenerative dementias, including Alzheimer's. Here, we report on a direct force measurement between paclitaxel-stabilized MTs coated with distinct Tau isoforms by synchrotron small-angle X-ray scattering (SAXS) of MT-Tau mixtures under osmotic pressure (P). In going from bare MTs to MTs with Tau coverage near the physiological submonolayer regime (Tau/tubulin-dimer molar ratio; ΦTau = 1/10), isoforms with longer N-terminal tails (NTTs) sterically stabilized MTs, preventing bundling up to PB ∼ 10,000-20,000 Pa, an order of magnitude larger than bare MTs. Tau with short NTTs showed little additional effect in suppressing the bundling pressure (PB ∼ 1,000-2,000 Pa) over the same range. Remarkably, the abrupt increase in PB observed for longer isoforms suggests a mushroom to brush transition occurring at 1/13 < ΦTau < 1/10, which corresponds to MT-bound Tau with NTTs that are considerably more extended than SAXS data for Tau in solution indicate. Modeling of Tau-mediated MT-MT interactions supports the hypothesis that longer NTTs transition to a polyelectrolyte brush at higher coverages. Higher pressures resulted in isoform-independent irreversible bundling because the polyampholytic nature of Tau leads to short-range attractions. These findings suggest an isoform-dependent biological role for regulation by Tau, with longer isoforms conferring MT steric stabilization against aggregation either with other biomacromolecules or into tight bundles, preventing loss of function in the crowded axon environment.


Subject(s)
Biophysical Phenomena , Microtubules/metabolism , tau Proteins/metabolism , Animals , Cattle , Humans , Models, Molecular , Osmotic Pressure , Protein Binding , Protein Isoforms/metabolism
18.
Adm Policy Ment Health ; 45(5): 741-750, 2018 09.
Article in English | MEDLINE | ID: mdl-29480503

ABSTRACT

We conducted a cost-effectiveness analysis (CEA) of two behavioral psychosocial interventions for children with ADHD-inattentive type: Child Life and Attention Skills (CLAS) program and parent-focused treatment (PFT) compared to community-based treatment as usual (TAU). The CEA evaluated cost per ADHD case resolved measured by parent and teacher reports of ADHD inattentive symptoms. Total cost per patient for CLAS, PFT, and TAU were $1559, $710, and $0. CLAS, the costliest treatment, was more effective than PFT and TAU. The incremental cost-effectiveness ratios (ICER) per disordered case resolved are: $3997 for CLAS versus TAU, $3227 for PFT versus TAU, and $4994 for CLAS versus PFT. PFT is the more cost-effective option based on initial CEA. However, CLAS may be comparably cost-effective by streamlining the model, which resulted in an ICER of $29 compared to PFT. Notably, cost for CLAS is substantially below the annual cost for unresolved ADHD.


Subject(s)
Attention Deficit Disorder with Hyperactivity/therapy , Behavior Therapy/methods , Parents/education , School Health Services/organization & administration , Behavior Therapy/economics , Child , Cost-Benefit Analysis , Female , Health Expenditures , Humans , Male , Models, Economic , Parenting , School Health Services/economics , Time Factors
20.
Biochim Biophys Acta Gen Subj ; 1861(1 Pt A): 3456-3463, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27632200

ABSTRACT

BACKGROUND: Microtubules (MTs) are protein nanotubes comprised of straight protofilaments (PFs), head to tail assemblies of αß-tubulin heterodimers. Previously, it was shown that Tau, a microtubule-associated protein (MAP) localized to neuronal axons, regulates the average number of PFs in microtubules with increasing inner radius observed for increasing Tau/tubulin-dimer molar ratio ΦTau at paclitaxel/tubulin-dimer molar ratio ΛPtxl=1/1. METHODS: We report a synchrotron SAXS and TEM study of the phase behavior of microtubules as a function of varying concentrations of paclitaxel (1/32≤ΛPtxl≤1/4) and Tau (human isoform 3RS, 0≤Φ3RS≤1/2) at room temperature. RESULTS: Tau and paclitaxel have opposing regulatory effects on microtubule bundling architectures and microtubule diameter. Surprisingly and in contrast to previous results at ΛPtxl=1/1 where microtubule bundles are absent, in the lower paclitaxel concentration regime (ΛPtxl≤1/4), we observe both microtubule doublets and triplets with increasing Tau. Furthermore, increasing paclitaxel concentration (up to ΛPtxl=1/1) slightly decreased the average microtubule diameter (by ~1 PF) while increasing Tau concentration (up to Φ3RS=1/2) significantly increased the diameter (by ~2-3 PFs). CONCLUSIONS: The suppression of Tau-mediated microtubule bundling with increasing paclitaxel is consistent with paclitaxel seeding more, but shorter, microtubules by rapidly exhausting tubulin available for polymerization. Microtubule bundles require the aggregate Tau-Tau attractions along the microtubule length to overcome individual microtubule thermal energies disrupting bundles. GENERAL SIGNIFICANCE: Investigating MAP-mediated interactions between microtubules (as it relates to in vivo behavior) requires the elimination or minimization of paclitaxel.


Subject(s)
Microtubules/metabolism , Paclitaxel/pharmacology , tau Proteins/metabolism , Animals , Cattle , Microtubules/drug effects , Microtubules/ultrastructure , Scattering, Small Angle , X-Ray Diffraction
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