ABSTRACT
BACKGROUND: Limited evidence exists on the safety of pharmacokinetic interactions of cytochrome P450 (CYP) 2D6 (CYP2D6)-metabolized opioids with antidepressants among older nursing home (NH) residents. OBJECTIVE: To investigate the associations of concomitant use of CYP2D6-metabolized opioids and antidepressants with clinical outcomes and opioid-related adverse events (ORAEs). DESIGN: Retrospective cohort study using a target trial emulation framework. SETTING: 100% Medicare NH sample linked to Minimum Data Set (MDS) from 2010 to 2021. PARTICIPANTS: Long-term residents aged 65 years and older receiving CYP2D6-metabolized opioids with a disease indication for antidepressant use. INTERVENTION: Initiating CYP2D6-inhibiting versus CYP2D6-neutral antidepressants that overlapped with use of CYP2D6-metabolized opioids for 1 day or more. MEASUREMENTS: Clinical outcomes were worsening pain, physical function, and depression from baseline to quarterly MDS assessments and were analyzed using modified Poisson regression models. The ORAE outcomes included counts of pain-related hospitalizations and emergency department (ED) visits, opioid use disorder (OUD), and opioid overdose and were analyzed with negative binomial or Poisson regression models. All models were adjusted for baseline covariates via inverse probability of treatment weighting. RESULTS: Among 29 435 identified residents, use of CYP2D6-metabolized opioids concomitantly with CYP2D6-inhibiting (vs. CYP2D6-neutral) antidepressants was associated with a higher adjusted rate ratio of worsening pain (1.13 [95% CI, 1.09 to 1.17]) and higher adjusted incidence rate ratios of pain-related hospitalization (1.37 [CI, 1.19 to 1.59]), pain-related ED visit (1.49 [CI, 1.24 to 1.80]), and OUD (1.93 [CI, 1.37 to 2.73]), with no difference in physical function, depression, and opioid overdose. LIMITATION: Findings are generalizable to NH populations only. CONCLUSION: Use of CYP2D6-metabolized opioids concomitantly with CYP2D6-inhibiting (vs. CYP2D6-neutral) antidepressants was associated with worsening pain and increased risk for most assessed ORAEs among older NH residents. PRIMARY FUNDING SOURCE: National Institute on Aging.
Subject(s)
Analgesics, Opioid , Antidepressive Agents , Cytochrome P-450 CYP2D6 , Nursing Homes , Humans , Analgesics, Opioid/adverse effects , Analgesics, Opioid/therapeutic use , Aged , Male , Female , Antidepressive Agents/adverse effects , Antidepressive Agents/therapeutic use , Antidepressive Agents/pharmacokinetics , Retrospective Studies , Cytochrome P-450 CYP2D6/metabolism , Aged, 80 and over , Drug Interactions , Depression/drug therapy , Cytochrome P-450 CYP2D6 Inhibitors/adverse effects , Pain/drug therapy , Hospitalization , United States , Homes for the Aged , Emergency Service, HospitalABSTRACT
The glycocalyx, a complex carbohydrate layer on cell surfaces, plays a crucial role in various biological processes. Understanding native glycocalyces' complexity is challenging due to their intricate and dynamic nature. Simplified mimics of native glycocalyces offer insights into glycocalyx functions but often lack molecular precision and fail to replicate key features of the natural analogues like molecular crowding and heteromultivalency. We introduce membrane-anchoring precision glycomacromolecules synthesized via solid-phase polymer synthesis (SPPoS) and thiol-induced, light-activated controlled radical polymerization (TIRP), enabling the construction of crowded and heteromultivalent glycocalyx mimetics with varying molecular weights and densities in giant unilamellar vesicles (GUVs). The incorporation and dynamics of glycomacromolecules in the GUVs are examined via microscopy and fluorescence correlation spectroscopy (FCS) and studies on lectin-carbohydrate-mediated adhesion of GUVs reveal inhibitory and promotional adhesion effects corresponding to different glycocalyx mimetic compositions, bridging the gap between synthetic models and native analogues.
ABSTRACT
Escherichia coli and other bacteria use adhesion receptors, such as FimH, to attach to carbohydrates on the cell surface as the first step of colonization and infection. Efficient inhibitors that block these interactions for infection treatment are multivalent carbohydrate-functionalized scaffolds. However, these multivalent systems often lead to the formation of large clusters of bacteria, which may pose problems for clearing bacteria from the infected site. Here, we present Man-containing Janus particles (JPs) decorated on one side with glycomacromolecules to target Man-specific adhesion receptors of E. coli. On the other side, poly(N-isopropylacrylamide) is attached to the particle hemisphere, providing temperature-dependent sterical shielding against binding and cluster formation. While homogeneously functionalized particles cluster with multiple bacteria to form large aggregates, glycofunctionalized JPs are able to form aggregates only with individual bacteria. The formation of large aggregates from the JP-decorated single bacteria can still be induced in a second step by increasing the temperature and making use of the collapse of the PNIPAM hemisphere. This is the first time that carbohydrate-functionalized JPs have been derived and used as inhibitors of bacterial adhesion. Furthermore, the developed JPs offer well-controlled single bacterial inhibition in combination with cluster formation upon an external stimulus, which is not achievable with conventional carbohydrate-functionalized particles.
Subject(s)
Bacterial Adhesion , Multifunctional Nanoparticles , Humans , Escherichia coli/chemistry , Carbohydrates/chemistry , TemperatureABSTRACT
BACKGROUND: Limited evidence exists on the short- and long-term safety of discontinuing versus continuing chronic opioid therapy (COT) among patients with Alzheimer's disease and related dementias (ADRD). METHODS: This cohort study was conducted among 162,677 older residents with ADRD and receipt of COT using a 100% Medicare nursing home sample. Discontinuation of COT was defined as no opioid refills for ≥90 days. Primary outcomes were rates of pain-related hospitalisation, pain-related emergency department visit, injury, opioid use disorder (OUD) and opioid overdose (OD) measured by diagnosis codes at quarterly intervals during 1- and 2-year follow-ups. Poisson regression models were fit using generalised estimating equations with inverse probability of treatment weights to model quarterly outcome rates between residents who discontinued versus continued COT. RESULTS: The study sample consisted of 218,040 resident episodes with COT; of these episodes, 180,916 residents (83%) continued COT, whereas 37,124 residents (17%) subsequently discontinued COT. Discontinuing (vs. continuing) COT was associated with higher rates of all outcomes in the first quarter, but these associations attenuated over time. The adjusted rates of injury, OUD and OD were 0, 69 and 60% lower at the 1-year follow-up and 11, 81 and 79% lower at the 2-year follow-up, respectively, for residents who discontinued versus continued COT, with no difference in the adjusted rates of pain-related hospitalisations or emergency department visits. CONCLUSIONS: The rates of adverse outcomes were higher in the first quarter but lower or non-differential at 1-year and 2-year follow-ups between COT discontinuers versus continuers among older residents with ADRD.
Subject(s)
Alzheimer Disease , Opioid-Related Disorders , Humans , Aged , United States/epidemiology , Analgesics, Opioid/adverse effects , Cohort Studies , Alzheimer Disease/diagnosis , Alzheimer Disease/drug therapy , Alzheimer Disease/epidemiology , Medicare , Opioid-Related Disorders/drug therapy , Pain/drug therapy , Retrospective StudiesABSTRACT
Inflammation drives the pathology of many neurological diseases. d-mannose has been found to exert an antiinflammatory effect in peripheral diseases, but its effects on neuroinflammation and inflammatory cells in the central nervous system have not been studied. We aimed to determine the effects of d-mannose on key macrophage/microglial functions-oxidative stress and phagocytosis. In murine experimental autoimmune encephalomyelitis (EAE), we found d-mannose improved EAE symptoms compared to phosphate-buffered saline (PBS)-control mice, while other monosaccharides did not. Multiagent molecular MRI performed to assess oxidative stress (targeting myeloperoxidase [MPO] using MPO-bis-5-hydroxytryptamide diethylenetriaminepentaacetate gadolinium [Gd]) and phagocytosis (using cross-linked iron oxide [CLIO] nanoparticles) in vivo revealed that d-mannose-treated mice had smaller total MPO-Gd+ areas than those of PBS-control mice, consistent with decreased MPO-mediated oxidative stress. Interestingly, d-mannose-treated mice exhibited markedly smaller CLIO+ areas and much less T2 shortening effect in the CLIO+ lesions compared to PBS-control mice, revealing that d-mannose partially blocked phagocytosis. In vitro experiments with different monosaccharides further confirmed that only d-mannose treatment blocked macrophage phagocytosis in a dose-dependent manner. As phagocytosis of myelin debris has been known to increase inflammation, decreasing phagocytosis could result in decreased activation of proinflammatory macrophages. Indeed, compared to PBS-control EAE mice, d-mannose-treated EAE mice exhibited significantly fewer infiltrating macrophages/activated microglia, among which proinflammatory macrophages/microglia were greatly reduced while antiinflammatory macrophages/microglia increased. By uncovering that d-mannose diminishes the proinflammatory response and boosts the antiinflammatory response, our findings suggest that d-mannose, an over-the-counter supplement with a high safety profile, may be a low-cost treatment option for neuroinflammatory diseases such as multiple sclerosis.
Subject(s)
Encephalomyelitis, Autoimmune, Experimental/drug therapy , Mannose/therapeutic use , Oxidative Stress/drug effects , Phagocytosis/drug effects , Animals , Drug Evaluation, Preclinical , Female , Mannose/pharmacology , Mice, Inbred C57BL , Molecular ImagingABSTRACT
Pathogens including viruses, bacteria, fungi, and parasites continue to shape our lives in profound ways every day. As we have learned to live in parallel with pathogens, we have gained a better understanding of the rules of engagement for how they bind, adhere, and invade host cells. One such mechanism involves the exploitation of host cell surface glycans for attachment/adhesion, one of the first steps of infection. This knowledge has led to the development of glycan-based diagnostics and therapeutics for the treatment and prevention of infection. One class of compounds that has become increasingly important are the glycopolymers. Glycopolymers are macromolecules composed of a synthetic scaffold presenting carbohydrates as side chain motifs. Glycopolymers are particularly attractive because their properties can be tuned by careful choice of the scaffold, carbohydrate/glycan, and overall presentation. In this review, we highlight studies over the past ten years that have examined the role of glycopolymers in pathogen adhesion and host cell infection, biofilm formation and removal, and drug delivery with the aim of examining the direct effects of these macromolecules on pathogen engagement. In addition, we also examine the role of glycopolymers as diagnostics for the detection and monitoring of pathogens.
Subject(s)
Carbohydrates , Polysaccharides , Carbohydrates/chemistry , Polysaccharides/chemistry , Polymers/chemistry , Drug Delivery SystemsABSTRACT
Nature is rich with examples of highly specialized biological materials produced by organisms for functions, including defense, hunting, and protection. Along these lines, velvet worms (Onychophora) expel a protein-based slime used for hunting and defense that upon shearing and dehydration forms fibers as stiff as thermoplastics. These fibers can dissolve back into their precursor proteins in water, after which they can be drawn into new fibers, providing biological inspiration to design recyclable materials. Elevated phosphorus content in velvet worm slime was previously observed and putatively ascribed to protein phosphorylation. Here, we show instead that phosphorus is primarily present as phosphonate moieties in the slime of distantly related velvet worm species. Using high-resolution nuclear magnetic resonance (NMR), natural abundance dynamic nuclear polarization (DNP), and mass spectrometry (MS), we demonstrate that 2-aminoethyl phosphonate (2-AEP) is associated with glycans linked to large slime proteins, while transcriptomic analyses confirm the expression of 2-AEP synthesizing enzymes in slime glands. The evolutionary conservation of this rare protein modification suggests an essential functional role of phosphonates in velvet worm slime and should stimulate further study of the function of this unusual chemical modification in nature.
Subject(s)
Organophosphonates , Proteins , Proteins/chemistry , Magnetic Resonance Spectroscopy , Phosphorus , Mass SpectrometryABSTRACT
For prey capture and defense, velvet worms eject an adhesive slime which has been established as a model system for recyclable complex liquids. Triggered by mechanical agitation, the liquid bio-adhesive rapidly transitions into solid fibers. In order to understand this mechanoresponsive behavior, here, the nanostructural organization of slime components are studied using small-angle scattering with neutrons and X-rays. The scattering intensities are successfully described with a three-component model accounting for proteins of two dominant molecular weight fractions and nanoscale globules. In contrast to the previous assumption that high molecular weight proteins-the presumed building blocks of the fiber core-are contained in the nanoglobules, it is found that the majority of slime proteins exist freely in solution. Only less than 10% of the slime proteins are contained in the nanoglobules, necessitating a reassessment of their function in fiber formation. Comparing scattering data of slime re-hydrated with light and heavy water reveals that the majority of lipids in slime are contained in the nanoglobules with homogeneous distribution. Vibrating mechanical impact under exclusion of air neither leads to formation of fibers nor alters the bulk structure of slime significantly, suggesting that interfacial phenomena and directional shearing are required for fiber formation.
Subject(s)
Nanostructures , Proteins , Proteins/chemistry , Scattering, Small Angle , Adhesives/chemistry , Scattering, RadiationABSTRACT
This study presents the preparation and phase behavior of glycan-functionalized polyelectrolytes for capturing carbohydrate-binding proteins and bacteria in liquid condensate droplets. The droplets are formed by complex coacervation of poly(active ester)-derived polyanions and polycations. This approach allows for a straightforward modular introduction of charged motifs and specifically interacting units; mannose and galactose oligomers are used here as first examples. The introduction of carbohydrates has a notable effect on the phase separation and the critical salt concentration, potentially by reducing the charge density. Two mannose binding species, concanavalin A (ConA) and Escherichia coli, are shown to not only specifically bind to mannose-functionalized coacervates but also to some degree to unfunctionalized, carbohydrate-free coacervates. This suggests non-carbohydrate-specific charge-charge interactions between the protein/bacteria and the droplets. However, when mannose interactions are inhibited or when non-binding galactose-functionalized polymers are used, interactions are significantly weakened. This confirms specific mannose-mediated binding functionalization and suggests that introducing carbohydrates reduces non-specific charge-charge interactions by a so far unidentified mechanism. Overall, the presented route toward glycan-presenting polyelectrolytes enables new functional liquid condensate droplets with specific biomolecular interactions.
Subject(s)
Lectins , Mannose , Lectins/metabolism , Polyelectrolytes/chemistry , Mannose/chemistry , Galactose/chemistry , Carbohydrates/chemistry , PolysaccharidesABSTRACT
PURPOSE: The aim of this work was to integrate the Therapeutic Drug Monitoring (TDM) with the model-informed precision dosing (MIPD) approach, using Physiologically-based Pharmacokinetic/Pharmacodynamic (PBPK/PD) modelling and simulation, to explore the relationship between amikacin exposure and estimated glomerular filtration rate (GFR) in critically ill patients with cancer. METHODS: In the TDM study, samples from 51 critically-ill patients with cancer treated with amikacin were analysed. Patients were stratified according to renal function based on GFR status. A full-body PBPK model with 12 organs model was developed using Simcyp V. 21, including steady-state volume of distribution of 0.21 L/kg and renal clearance of 6.9 L/h in healthy adults. PK parameters evaluated were within the 2-fold error range. RESULTS: During the validation step, predicted vs observed amikacin clearance values after single infusion dose in patients with normal renal function, mild and moderate renal impairment were 7.6 vs 8.1 L/h (7.5 mg/kg dose); 3.8 vs 4.5 L/h (1500 mg dose) and 2.2 vs 3.1 L/h (25 mg/kg dose), respectively. However, predicted vs observed amikacin clearance after a single dose infusion of 1400 mg in critically-ill patients with cancer were 1.46 vs 1.63 (P = 0.6406) L/h (severe), 2.83 vs 1.08 (P < 0.05) L/h (moderate), 4.23 vs 2.49 (P = 0.0625) L/h (mild) and 7.41 vs 3.36 (P < 0.05) L/h (normal renal function). CONCLUSION: This study demonstrated that estimated GFR did not predict amikacin elimination in critically-ill patients with cancer. Further studies are necessary to find amikacin PK covariates to optimize the pharmacotherapy in this population. Therefore, TDM of amikacin is imperative in cancer patients.
Subject(s)
Amikacin , Neoplasms , Adult , Humans , Amikacin/therapeutic use , Critical Illness/therapy , Glomerular Filtration Rate , Drug Monitoring , Neoplasms/drug therapy , Anti-Bacterial Agents/therapeutic useABSTRACT
PURPOSE: Statins are among the most prevalent medications prescribed and associated with adverse events that may prompt additional treatment (i.e., a prescribing cascade). No comprehensive assessment of statin-related prescribing cascades has been performed to our knowledge. METHODS: We utilized sequence symmetry analysis to iteratively screen prescribing sequences of all therapeutic classes ("marker" classes) based on Level 4 Anatomical Therapeutic Chemical codes among adult statin initiators, using IBM Marketscan commercial and Medicare supplemental claims databases (2005-2019). Order of initiation and secular trend-adjusted sequence ratios were calculated for each statin-marker class dyad, among marker class initiators ±90 days of statin initiation. Among signals classified as prescribing cascades, we calculated naturalistic number needed to harm (NNTH) within 1 year as the inverse of the excess risk among exposed. RESULTS: We identified 2 265 519 statin initiators (mean ± SD age, 56.4 ± 12.0 years; 48.7% women; 7.5% with cardiovascular disease). Simvastatin (34.4% of statin initiators) and atorvastatin (33.9%) were the most commonly initiated statins. We identified 160 significant statin-marker class dyad signals, of which 35.6% (n = 57) were classified as potential prescribing cascades. Of the top 25 strongest signals (lowest NNTH), 12 were classified as potential prescribing cascades, including osmotically acting laxatives (NNTH, 44, 95% CI 43-46), opioids + non-opioid combination analgesics (81, 95% CI 74-91), and first-generation cephalosporins (204, 95% CI 175-246). CONCLUSIONS: Using high-throughput sequence symmetry analysis screening, we identified previously known prescribing cascades as well as potentially new prescribing cascades based on known and unknown statin-related adverse events.
Subject(s)
Hydroxymethylglutaryl-CoA Reductase Inhibitors , Aged , Adult , Humans , Female , United States , Middle Aged , Male , Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use , High-Throughput Screening Assays , Medicare , Simvastatin/adverse effects , AtorvastatinABSTRACT
The homotrimeric P2X7 receptor (P2X7R) is expressed by virtually all cells of the innate and adaptive immune system and plays a crucial role in various pathophysiological processes such as autoimmune and neurodegenerative diseases, inflammation, neuropathic pain and cancer. Consequently, the P2X7R is considered a promising target for therapy and diagnosis. As the development of tracers comes hand-in-hand with the development of potent and selective receptor ligands, there is a rising number of PET tracers available in preclinical and clinical studies. This review analyzes the development of P2X7R positron emission tomography (PET) tracers and their potential in various PET imaging applications.
Subject(s)
Neoplasms , Neurodegenerative Diseases , Humans , Receptors, Purinergic P2X7 , Positron-Emission Tomography/methods , Inflammation/diagnostic imaging , Inflammation/drug therapy , Neoplasms/diagnostic imaging , Neoplasms/drug therapyABSTRACT
Mycobacterium tuberculosis (Mtb) exists in various metabolic states, including a nonreplicating persister (NRP) phenotype which may affect response to therapy. We have adopted a model-informed strategy to accelerate discovery of effective Mtb treatment regimens and previously found pretomanid (PMD), moxifloxacin (MXF), and bedaquiline (BDQ) to readily kill logarithmic- and acid-phase Mtb. Here, we studied multiple concentrations of each drug in flask-based, time-kill studies against NRP Mtb in single-, two- and three-drug combinations, including the active M2 metabolite of BDQ. We used nonparametric population algorithms in the Pmetrics package for R to model the data and to simulate the 95% confidence interval of bacterial population decline due to the two-drug combination regimen of PMD + MXF and compared this to observed declines with three-drug regimens. PMD + MXF at concentrations equivalent to average or peak human concentrations effectively eradicated Mtb. Unlike other states for Mtb, we observed no sustained emergence of less susceptible isolates for any regimen. The addition of BDQ as a third drug significantly (P < 0.05) shortened time to total bacterial suppression by 3 days compared to the two-drug regimen, similar to our findings for Mtb in logarithmic or acid growth phases.
Subject(s)
Mycobacterium tuberculosis , Animals , Humans , Antitubercular Agents/pharmacology , Moxifloxacin/pharmacology , Drug Combinations , PhenotypeABSTRACT
The biomolecular interaction of ligand-presenting switchable microgels is studied with respect to the polymer type, composition, and structure of the microgels. Monodisperse microgels are prepared through precipitation polymerization of N-isopropylacrylamide (PNIPAM microgels) or oligo(ethylene glycol methacrylamide)s (POEGMA microgels) in the presence of crosslinkers or in their absence (self-crosslinked). Functionalization with mannose or biotin as model ligands and affinity measurements upon heating/cooling are conducted to obtain mechanistic insights into how the microgel phase transition affects the specific interactions. In particular, we are interested in adjusting the crosslinking, swelling degree, and ligand density of mannose-functionalized microgels to reversibly catch and release mannose binding Escherichia coli by setting the temperature below or above the microgels' volume phase transition temperature (VPTT). The increased mannose density for collapsed microgels above the VPTT results in stronger E. coli binding. Detachment of E. coli by reswelling the microgels below the VPTT is achieved only for self-crosslinked microgels showing a stronger decrease in ligand density compared to microgels with dedicated crosslinkers. Owing to a reduced mannose density in the shell of POEGMA microgels, their E. coli binding was lower compared to PNIPAM microgels, as supported by ultraresolution microscopy. Importantly, an inverse temperature-controlled binding of microgels decorated with hydrophilic mannose and hydrophobic biotin ligands is observed. This indicates that hydrophobic ligands are inaccessible in the collapsed hydrophobic network above the VPTT, whereas hydrophilic mannose units are then enriched at the microgel-water interface and thus are more accessible.
Subject(s)
Microgels , Biotin , Escherichia coli , Gels/chemistry , Hydrophobic and Hydrophilic Interactions , Ligands , MannoseABSTRACT
BACKGROUND: A variety of management options (e.g., disease-modifying therapy, lifestyle interventions, rehabilitation) are available for persons with relapsing-remitting multiple sclerosis (MS). Besides coping with the diagnosis, persons with MS have to make complex decisions, e.g., regarding disease-modifying therapies. In addition to factual information, reports of patient experiences may support other patients in their decision-making. Therefore, we developed a website presenting patient experiences illustrated by video, audio and text files. This study aimed to test the acceptability and usability of a website with patient experiences with MS. METHODS: A mixed-methods approach was applied. A total of 69 participants visited the German "Patient Experiences with MS (PExMS)" website and among them, 50 persons with MS and 6 experts completed an online survey. In total, 18 participants took part in telephone interviews or focus groups. Data from the survey were analysed using descriptive statistics. Qualitative data were analysed using thematic analysis. RESULTS: Both quantitative and qualitative responses suggest that the PExMS website was viewed positively by patients and experts. 94% of persons with MS agreed that the information was comprehensible and reliable. 54% felt encouraged to share their health problems with others after having studied the website. 74% claimed to use the website if they had to make a decision regarding their health. Qualitative responses deduced from the website fell into 5 key themes: (1) web design, appearance, and functionality, (2) content, (3) usability, (4) satisfaction, and (5) loyalty. The search for persons of similar age and with comparable experiences was a major driving force to navigate the website. The material on the website was perceived as diverse, covering both positive and negative experiences in daily living with MS. All participants greatly appreciated having access to other people's experiences online and judged the material on the website as particularly helpful in decision-making for disease-modifying therapies. CONCLUSIONS: The findings suggest that the PExMS website might have the potential to be a useful source of audio-visual information for persons with MS. Given the lack of websites available to patients with experiential information, health care professionals may be encouraged to routinely inform patients about this website at regular appointments.
Subject(s)
Multiple Sclerosis, Relapsing-Remitting , Multiple Sclerosis , Focus Groups , Humans , Multiple Sclerosis, Relapsing-Remitting/therapy , Surveys and QuestionnairesABSTRACT
Dimethyl fumarate, an approved treatment for relapsing-remitting multiple sclerosis, exerts pleiotropic effects on immune cells as well as CNS resident cells. Here, we show that dimethyl fumarate exerts a profound alteration of the metabolic profile of human CD4+ as well as CD8+ T cells and restricts their antioxidative capacities by decreasing intracellular levels of the reactive oxygen species scavenger glutathione. This causes an increase in mitochondrial reactive oxygen species levels accompanied by an enhanced mitochondrial stress response, ultimately leading to impaired mitochondrial function. Enhanced mitochondrial reactive oxygen species levels not only result in enhanced T-cell apoptosis in vitro as well as in dimethyl fumarate-treated patients, but are key for the well-known immunomodulatory effects of dimethyl fumarate both in vitro and in an animal model of multiple sclerosis, i.e. experimental autoimmune encephalomyelitis. Indeed, dimethyl fumarate immune-modulatory effects on T cells were completely abrogated by pharmacological interference of mitochondrial reactive oxygen species production. These data shed new light on dimethyl fumarate as bona fide immune-metabolic drug that targets the intracellular stress response in activated T cells, thereby restricting mitochondrial function and energetic capacity, providing novel insight into the role of oxidative stress in modulating cellular immune responses and T cell-mediated autoimmunity.
Subject(s)
Antioxidants/pharmacology , Autoimmunity/drug effects , CD4-Positive T-Lymphocytes/drug effects , CD8-Positive T-Lymphocytes/drug effects , Dimethyl Fumarate/pharmacology , Immunosuppressive Agents/pharmacology , Adult , Animals , Antioxidants/therapeutic use , Autoimmunity/physiology , CD4-Positive T-Lymphocytes/physiology , CD8-Positive T-Lymphocytes/physiology , Cohort Studies , Dimethyl Fumarate/therapeutic use , Female , Humans , Immunosuppressive Agents/therapeutic use , Male , Mice , Mice, Inbred C57BL , Middle Aged , Multiple Sclerosis, Relapsing-Remitting/drug therapy , Multiple Sclerosis, Relapsing-Remitting/immunology , Multiple Sclerosis, Relapsing-Remitting/metabolism , Young AdultABSTRACT
BACKGROUND: Managing multiple sclerosis (MS) includes different treatment approaches. Rehabilitation is a key strategy in MS for improving functioning, activity and participation. As part of a larger study on overall patient experiences with different treatment approaches, this study aims to give an overview of different patients' experiences and perspectives on inpatient rehabilitation in MS. METHODS: We conducted problem-centered interviews in 50 persons with MS in Germany, of whom most had relapsing-remitting MS. We used the maximum variation sampling method during recruitment. Data were analyzed thematically. RESULTS: As a result of the analysis, three major themes were identified: 1) factors contributing to the decision-making concerning rehabilitation, 2) experience with the rehabilitation setting, 3) benefits of rehabilitation treatments. The treating physicians' attitude had a major impact on the decision to either opt for rehabilitation or not. Setting goals prior to rehabilitation was given a high priority. Exchanging experiences with other persons with MS presented a major benefit from rehabilitation while for some being separated from regular daily life resulted in a more ambiguous attitude ranging from appreciation of escaping daily hassles to substantial behavioral change management. CONCLUSION: Patients reported various experiences in the process of decision-making with regard to rehabilitation. Physicians´ advice, goal setting and the selection of the most suitable rehabilitation clinic were considered most relevant.
Subject(s)
Multiple Sclerosis, Relapsing-Remitting , Multiple Sclerosis , Germany , Humans , Qualitative Research , Research DesignABSTRACT
The repurposed agent moxifloxacin has become an important addition to the physician's armamentarium for the therapy of Mycobacterium tuberculosis When a drug is administered, we need to have metrics for success. As for most antimicrobial chemotherapy, we contend that for Mycobacterium tuberculosis therapy, these metrics should be a decline in the susceptible bacterial burden and the suppression of amplification of less-susceptible populations. To achieve optimal outcomes relative to these metrics, a dose and schedule of administration need to be chosen. For large populations of patients, there are true between-patient differences in important pharmacokinetic parameters. These distributions of parameter values may have an impact on these metrics, depending on what measure of drug exposure drives the metrics. To optimize dose and schedule choice of moxifloxacin, we performed a dose fractionation experiment in the hollow fiber infection model. We examined 12-, 24-, and 48-h dosing intervals with doses of 200, 400, and 800 mg for each interval, respectively. Within each interval, we had an arm where half-lives of 12, 8, and 4 h were simulated. We attempted to keep the average concentration (Cavg) or area under the concentration-time curve (AUC) constant across arms. We found that susceptible bacterial load decline was linked to Cavg, as we had indicated previously. Resistance suppression, a nonmonotonic function, had minimum concentration (Cmin) as the linked index. The 48-h interval with the 4-h half-life had the largest less-susceptible population. Balancing bacterial kill, resistance suppression, toxicity (linked to peak concentration [Cpeak]), and adherence, we conclude that the dose of 400 mg daily is optimal for moxifloxacin.
Subject(s)
Antitubercular Agents , Tuberculosis , Antitubercular Agents/therapeutic use , Area Under Curve , Fluoroquinolones , Half-Life , Humans , Microbial Sensitivity Tests , Moxifloxacin , Tuberculosis/drug therapyABSTRACT
Mycobacterium tuberculosis metabolic state affects the response to therapy. Quantifying the effect of antimicrobials in the acid and nonreplicating metabolic phases of M. tuberculosis growth will help to optimize therapy for tuberculosis. As a brute-force approach to all possible drug combinations against M. tuberculosis in all different metabolic states is impossible, we have adopted a model-informed strategy to accelerate the discovery. Using multiple concentrations of each drug in time-kill studies, we examined single drugs and two- and three-drug combinations of pretomanid, moxifloxacin, and bedaquiline plus its active metabolite against M. tuberculosis in its acid-phase metabolic state. We used a nonparametric modeling approach to generate full distributions of interaction terms between pretomanid and moxifloxacin for susceptible and less susceptible populations. From the model, we could predict the 95% confidence interval of the simulated total bacterial population decline due to the 2-drug combination regimen of pretomanid and moxifloxacin and compare this to observed declines with 3-drug regimens. We found that the combination of pretomanid and moxifloxacin at concentrations equivalent to average or peak human concentrations effectively eradicated M. tuberculosis in its acid growth phase and prevented emergence of less susceptible isolates. The addition of bedaquiline as a third drug shortened time to total and less susceptible bacterial suppression by 8 days compared to the 2-drug regimen, which was significantly faster than the 2-drug kill.
Subject(s)
Mycobacterium tuberculosis , Animals , Antitubercular Agents/therapeutic use , Drug Combinations , Drug Therapy, Combination , Humans , MoxifloxacinABSTRACT
The Mycobacterium tuberculosis drug discovery effort has generated a substantial number of new/repurposed drugs for therapy for this pathogen. The arrival of these drugs is welcome, but another layer of difficulty has emerged. Single agent therapy is insufficient for patients with late-stage tuberculosis because of resistance emergence. To achieve our therapeutic ends, it is requisite to identify optimal combination regimens. These regimens go through a lengthy and expensive evaluative process. If we have a modest group of 6 to 8 new or repurposed agents, this translates into 15 to 28 possible 2-drug combinations. There is neither time nor resources to give an extensive evaluation for all combinations. We sought a screening procedure that would identify combinations that had a high likelihood of achieving good bacterial burden decline. We examined pretomanid, moxifloxacin, linezolid, and bedaquiline in log-phase growth, acid-phase growth, and nonreplicative persister (NRP) phase in the Greco interaction model. We employed the interaction term α and the calculated bacterial burden decline as metrics to rank different regimens in different metabolic states. No relationship was found between α and bacterial kill. We chose bacterial kill as the prime metric. The combination of pretomanid plus moxifloxacin emerged as the clear frontrunner, as the largest bacterial declines were seen in log phase and acid phase with this regimen and it was second best in NRP phase. Bedaquiline also produced good kill. This screening process may identify optimal combinations that can be further evaluated in both the hollow-fiber infection model and in animal models of Mycobacterium tuberculosis infection.