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1.
Eur J Appl Physiol ; 2024 May 02.
Article in English | MEDLINE | ID: mdl-38695912

ABSTRACT

PURPOSE: We compared the effects of low-volume combined aerobic and resistance high-intensity interval training (C-HIIT), combined moderate-intensity continuous training (C-MICT) and waitlist control (CON) on vascular health after 8-weeks of supervised training, and an additional 10-months of self-directed training, in adults with type 2 diabetes (T2D). METHODS: Sixty-nine low active adults with T2D were randomised to 8-weeks of supervised C-HIIT (3 times/week, 78-min/week), C-MICT (current exercise guidelines, 4 times/week, 210-min/week) or CON. CON underwent usual care for 8-weeks before being re-randomised to C-HIIT or C-MICT. This was followed by 10-months of self-directed training for participants in C-HIIT and C-MICT. Vascular outcomes were evaluated at baseline, 8-weeks, and 12-months. RESULTS: After 8-weeks, supervised C-HIIT significantly improved relative flow-mediated dilation (FMD) compared with CON (mean difference [MD] 0.8% [0.1, 1.4], p = 0.025). Although not significantly different from CON, the magnitude of change in relative FMD following 8-weeks of supervised C-MICT was similar (MD 0.8% [-0.1, 1.7], p = 0.080). There were no differences in haemodynamic indices, carotid-femoral pulse wave velocity (cfPWV), or aortic reservoir pressure between groups at 8-weeks. After 12-months, there was a significant reduction in haemodynamic indices (time effect, p < 0.05) for both C-HIIT and C-MICT, with no between-group difference. The reduction in cfPWV over 12-months was significantly greater in C-MICT than C-HIIT (group × time effect, p = 0.018). There was no difference in FMD over time or between groups at 12-months. CONCLUSIONS: Short-term supervised C-HIIT and C-MICT both increased brachial artery FMD compared with CON. Long-term C-HIIT and C-MICT were beneficial for improving haemodynamic indices, but not brachial artery FMD. C-MICT was superior to C-HIIT for improving cfPWV at 12-months. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry Identifier ACTRN12615000475549.

2.
Proc Natl Acad Sci U S A ; 118(39)2021 09 28.
Article in English | MEDLINE | ID: mdl-34551980

ABSTRACT

As a common protein modification, asparagine-linked (N-linked) glycosylation has the capacity to greatly influence the biological and biophysical properties of proteins. However, the routine use of glycosylation as a strategy for engineering proteins with advantageous properties is limited by our inability to construct and screen large collections of glycoproteins for cataloguing the consequences of glycan installation. To address this challenge, we describe a combinatorial strategy termed shotgun scanning glycomutagenesis in which DNA libraries encoding all possible glycosylation site variants of a given protein are constructed and subsequently expressed in glycosylation-competent bacteria, thereby enabling rapid determination of glycosylatable sites in the protein. The resulting neoglycoproteins can be readily subjected to available high-throughput assays, making it possible to systematically investigate the structural and functional consequences of glycan conjugation along a protein backbone. The utility of this approach was demonstrated with three different acceptor proteins, namely bacterial immunity protein Im7, bovine pancreatic ribonuclease A, and human anti-HER2 single-chain Fv antibody, all of which were found to tolerate N-glycan attachment at a large number of positions and with relatively high efficiency. The stability and activity of many glycovariants was measurably altered by N-linked glycans in a manner that critically depended on the precise location of the modification. Structural models suggested that affinity was improved by creating novel interfacial contacts with a glycan at the periphery of a protein-protein interface. Importantly, we anticipate that our glycomutagenesis workflow should provide access to unexplored regions of glycoprotein structural space and to custom-made neoglycoproteins with desirable properties.


Subject(s)
Asparagine/chemistry , Carrier Proteins/metabolism , Escherichia coli Proteins/metabolism , Glycoproteins/metabolism , Polysaccharides/metabolism , Protein Processing, Post-Translational , Ribonuclease, Pancreatic/metabolism , Single-Chain Antibodies/metabolism , Amino Acid Sequence , Animals , Carrier Proteins/chemistry , Carrier Proteins/genetics , Cattle , Escherichia coli Proteins/chemistry , Escherichia coli Proteins/genetics , Glycoproteins/chemistry , Glycoproteins/genetics , Glycosylation , Humans , Polysaccharides/chemistry , Polysaccharides/genetics , Protein Conformation , Protein Engineering , Receptor, ErbB-2/antagonists & inhibitors , Receptor, ErbB-2/immunology , Ribonuclease, Pancreatic/chemistry , Ribonuclease, Pancreatic/genetics , Single-Chain Antibodies/chemistry , Single-Chain Antibodies/genetics
3.
Pharmacol Rev ; 73(2): 847-859, 2021 04.
Article in English | MEDLINE | ID: mdl-33712517

ABSTRACT

The popularity of botanical and other purported medicinal natural products (NPs) continues to grow, especially among patients with chronic illnesses and patients managed on complex prescription drug regimens. With few exceptions, the risk of a given NP to precipitate a clinically significant pharmacokinetic NP-drug interaction (NPDI) remains understudied or unknown. Application of static or dynamic mathematical models to predict and/or simulate NPDIs can provide critical information about the potential clinical significance of these complex interactions. However, methods used to conduct such predictions or simulations are highly variable. Additionally, published reports using mathematical models to interrogate NPDIs are not always sufficiently detailed to ensure reproducibility. Consequently, guidelines are needed to inform the conduct and reporting of these modeling efforts. This recommended approach from the Center of Excellence for Natural Product Drug Interaction Research describes a systematic method for using mathematical models to interpret the interaction risk of NPs as precipitants of potential clinically significant pharmacokinetic NPDIs. A framework for developing and applying pharmacokinetic NPDI models is presented with the aim of promoting accuracy, reproducibility, and generalizability in the literature. SIGNIFICANCE STATEMENT: Many natural products (NPs) contain phytoconstituents that can increase or decrease systemic or tissue exposure to, and potentially the efficacy of, a pharmaceutical drug; however, no regulatory agency guidelines exist to assist in predicting the risk of these complex interactions. This recommended approach from a multi-institutional consortium designated by National Institutes of Health as the Center of Excellence for Natural Product Drug Interaction Research provides a framework for modeling pharmacokinetic NP-drug interactions.


Subject(s)
Biological Products , Pharmaceutical Preparations , Drug Interactions , Humans , Reproducibility of Results
4.
Hosp Pharm ; 59(3): 359-366, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38764999

ABSTRACT

Background: Volume overload (VO) is common in the intensive care unit (ICU) and associated with negative outcomes. Approaches have been investigated to curtail VO; however, none specifically focused on medication diluent volume optimization. Objective: Investigate the impact of a pharmacist-driven medication diluent volume optimization protocol on fluid balance in critically ill patients. Methods: A prospective, pilot study was conducted in a medical ICU during October 2021 to December 2021 (pre) and February 2022 to April 2022 (post). A pharmacist-driven medication diluent volume optimization protocol focusing on vasopressor and antimicrobial diluent volumes was implemented. Demographics and clinical data were collected during ICU admission up to 7 days. The primary outcome was net fluid balance on day 3. Secondary outcomes were medication volumes administered, net fluid balance, ICU length of stay, and mortality. Results: Supply chain shortages caused the study to stop at the end of February 2022. Overall, 152 patients were included (123 pre group, 29 post group). The most common admission diagnosis was acute respiratory failure (35%). Vasopressors and antimicrobials were utilized in 47% and 66% of patients, respectively. Net fluid balance on day 3 was greater but not significant in the post group (227.1 mL [-1840.3 to 3483.7] vs 2012.3 mL [-2686.0 to 4846.0]; P = .584). Antimicrobial diluent volumes were significantly less in the post group. No differences were seen in other secondary outcomes. Protocol group assignment was not associated with net fluid balance on day 3. Conclusion: Despite decreasing antimicrobial volume contributions, optimizing diluent volumes alone did not significantly impact overall volume status. Future studies should focus on comprehensive approaches to medication diluent optimization and fluid stewardship.

5.
Dig Dis Sci ; 68(5): 2123-2139, 2023 05.
Article in English | MEDLINE | ID: mdl-36538276

ABSTRACT

BACKGROUND: High-Intensity Interval Training (HIIT) involves bursts of high-intensity exercise interspersed with lower-intensity exercise recovery. HIIT may benefit cardiometabolic health in people with nonalcoholic steatohepatitis (NASH). AIMS: We aimed to examine the safety, feasibility, and efficacy of 12-weeks of supervised HIIT compared with a sham-exercise control (CON) for improving aerobic fitness and peripheral insulin sensitivity in biopsy-proven NASH. METHODS: Participants based in the community [(n = 14, 56 ± 10 years, BMI 39.2 ± 6.7 kg/m2, 64% male), NAFLD Activity Score 5 (range 3-7)] were randomized to 12-weeks of supervised HIIT (n = 8, 4 × 4 min at 85-95% maximal heart rate, interspersed with 3 min active recovery; 3 days/week) or CON (n = 6, stretching; 3 days/week). Safety (adverse events) and feasibility determined as ≥ 70% program completion and ≥ 70% global adherence (including session attendance, interval intensity adherence, and duration adherence) were assessed. Changes in cardiorespiratory fitness (V̇O2peak), exercise capacity (time-on-test) and peripheral insulin sensitivity (euglycemic hyperinsulinemic clamp) were assessed. Data were analysed using ANCOVA with baseline value as the covariate. RESULTS: There were no HIIT-related adverse events and HIIT was globally feasible [program completion 75%, global adherence 100% (including adherence to session 95.4 ± 7.3%, interval intensity 95.3 ± 6.0% and duration 96.8 ± 2.4%)]. A large between-group effect was observed for exercise capacity [mean difference 134.2 s (95% CI 19.8, 248.6 s), ƞ2 0.44, p = 0.03], improving in HIIT (106.2 ± 97.5 s) but not CON (- 33.4 ± 43.3 s), and for peripheral insulin sensitivity [mean difference 3.4 mg/KgLegFFM/min (95% CI 0.9,6.8 mg/KgLegFFM/min), ƞ2 0.32, p = 0.046], improving in HIIT (1.0 ± 0.8 mg/KgLegFFM/min) but not CON (- 3.1 ± 1.2 mg/KgLegFFM/min). CONCLUSIONS: HIIT is safe, feasible and efficacious for improving exercise capacity and peripheral insulin sensitivity in people with NASH. CLINICAL TRIAL REGISTRATION NUMBER: Australian New Zealand Clinical Trial Registry (anzctr.org.au) identifier ACTRN12616000305426 (09/03/2016).


Subject(s)
High-Intensity Interval Training , Insulin Resistance , Non-alcoholic Fatty Liver Disease , Humans , Male , Female , Non-alcoholic Fatty Liver Disease/therapy , Australia , Exercise/physiology
6.
Nat Chem Biol ; 16(10): 1062-1070, 2020 10.
Article in English | MEDLINE | ID: mdl-32719555

ABSTRACT

A major objective of synthetic glycobiology is to re-engineer existing cellular glycosylation pathways from the top down or construct non-natural ones from the bottom up for new and useful purposes. Here, we have developed a set of orthogonal pathways for eukaryotic O-linked protein glycosylation in Escherichia coli that installed the cancer-associated mucin-type glycans Tn, T, sialyl-Tn and sialyl-T onto serine residues in acceptor motifs derived from different human O-glycoproteins. These same glycoengineered bacteria were used to supply crude cell extracts enriched with glycosylation machinery that permitted cell-free construction of O-glycoproteins in a one-pot reaction. In addition, O-glycosylation-competent bacteria were able to generate an antigenically authentic Tn-MUC1 glycoform that exhibited reactivity with antibody 5E5, which specifically recognizes cancer-associated glycoforms of MUC1. We anticipate that the orthogonal glycoprotein biosynthesis pathways developed here will provide facile access to structurally diverse O-glycoforms for a range of important scientific and therapeutic applications.


Subject(s)
Escherichia coli/metabolism , Glycoproteins/biosynthesis , Polysaccharides/metabolism , Protein Engineering , Antigens, Tumor-Associated, Carbohydrate/biosynthesis , Cell-Free System , Flow Cytometry/methods , Glycosylation , Humans , Polysaccharides/genetics
7.
J Interv Cardiol ; 2022: 9926423, 2022.
Article in English | MEDLINE | ID: mdl-35832534

ABSTRACT

Objectives: This study was conducted to determine why heart teams recommended transcatheter aortic valve replacement (TAVR) versus surgical AVR (SAVR) for patients at low predicted risk of mortality (PROM) and describe outcomes of these cases. Background: Historically, referral to TAVR was based predominately on the Society of Thoracic Surgeons (STS) risk model's PROM >3%. In selected cases, heart teams had latitude to overrule these scores. The clinical reasons and outcomes for these cases are unclear. Methods: Retrospective data were gathered for all TAVR and SAVR cases conducted by 9 hospitals between 2013 and 2017. Results: Cases included TAVR patients with STS PROM >3% (n = 2,711) and ≤3% (n = 415) and SAVR with STS PROM ≤3% (n = 1,438). Leading reasons for recommending TAVR in the PROM ≤3% group were frailty (57%), hostile chest (22%), severe lung disease (16%), and morbid obesity (13%), and 44% of cases had multiple reasons. Most postoperative and 30-day outcomes were similar between TAVR groups, but the STS PROM ≤3% group had a one-day shorter length of stay (2.5 ± 3.4 vs. 3.5 ± 4.7 days; p ≤ 0.001) and higher one-year survival (91.6% vs. 86.0%, p=0.002). In patients with STS PROM ≤3%, 30-day mortality was higher for TAVR versus SAVR (2.0% vs. 0.6%; p < 0.001). Conclusions: Heart teams recommended TAVR in patients with STS PROM ≤3% primarily due to frailty, hostile chest, severe lung disease, and/or morbid obesity. Similar postoperative outcomes between these patients and those with STS PROM >3% suggest that decisions to overrule STS PROM ≤3% were merited and may have reduced SAVR 30-day mortality rate.


Subject(s)
Aortic Valve Stenosis , Frailty , Heart Valve Prosthesis Implantation , Lung Diseases , Obesity, Morbid , Transcatheter Aortic Valve Replacement , Aortic Valve/surgery , Aortic Valve Stenosis/surgery , Frailty/etiology , Frailty/surgery , Heart Valve Prosthesis Implantation/adverse effects , Humans , Lung Diseases/etiology , Lung Diseases/surgery , Retrospective Studies , Risk Factors , Transcatheter Aortic Valve Replacement/adverse effects , Treatment Outcome
8.
J Ultrasound Med ; 41(1): 33-40, 2022 Jan.
Article in English | MEDLINE | ID: mdl-33797767

ABSTRACT

Point-of-care ultrasound (POCUS) is becoming an essential skill for internists. To date, there are no professional guidelines for how POCUS skills should be taught to medical students. A panel of POCUS experts from seven academic medical centers in the United States was convened to describe the components of independently developed IM clerkship POCUS training programs, identify areas of similarity and difference, and propose recommendations for alignment.


Subject(s)
Point-of-Care Systems , Humans
9.
Risk Anal ; 42(7): 1472-1487, 2022 07.
Article in English | MEDLINE | ID: mdl-33651900

ABSTRACT

Reaching net-zero for global greenhouse gas emissions by the year 2050 will require a portfolio of new technologies and approaches, potentially requiring direct removal and sequestration of atmospheric carbon dioxide using negative emissions technologies (NETs). Since energy and climate systems are fundamentally interconnected it is important that we understand the impacts of policy decisions and their associated controversies in other related technologies and sectors. Using a secondary analysis of data from a series of deliberative workshops conducted with lay publics in the United Kingdom, we suggest that perceptions of CO2 removal technologies were negatively impacted by risk perceptions and recent policy decisions surrounding shale gas and fracking. Using the social amplification of risk framework, we argue that heightened risk perceptions have extended via "ripple effects" across these technologies. Participants' attitudes were underpinned by deeper misgivings regarding the actions and motives of experts and policymakers; a pervasive discourse of "but they told us it was safe" regarding fracking negatively affected people's trust in assurances of the safety and efficacy of CO2 removal. This has the potential to undermine attempts to build societal agreement around future deployment of CO2 removal technologies.


Subject(s)
Carbon Dioxide , Hydraulic Fracking , Carbon Dioxide/analysis , Climate , Greenhouse Effect , Humans , Natural Gas
10.
J Biomed Sci ; 28(1): 37, 2021 May 13.
Article in English | MEDLINE | ID: mdl-33985508

ABSTRACT

BACKGROUND: Low cardiorespiratory fitness (V̇O2peak) is highly associated with chronic disease and mortality from all causes. Whilst exercise training is recommended in health guidelines to improve V̇O2peak, there is considerable inter-individual variability in the V̇O2peak response to the same dose of exercise. Understanding how genetic factors contribute to V̇O2peak training response may improve personalisation of exercise programs. The aim of this study was to identify genetic variants that are associated with the magnitude of V̇O2peak response following exercise training. METHODS: Participant change in objectively measured V̇O2peak from 18 different interventions was obtained from a multi-centre study (Predict-HIIT). A genome-wide association study was completed (n = 507), and a polygenic predictor score (PPS) was developed using alleles from single nucleotide polymorphisms (SNPs) significantly associated (P < 1 × 10-5) with the magnitude of V̇O2peak response. Findings were tested in an independent validation study (n = 39) and compared to previous research. RESULTS: No variants at the genome-wide significance level were found after adjusting for key covariates (baseline V̇O2peak, individual study, principal components which were significantly associated with the trait). A Quantile-Quantile plot indicates there was minor inflation in the study. Twelve novel loci showed a trend of association with V̇O2peak response that reached suggestive significance (P < 1 × 10-5). The strongest association was found near the membrane associated guanylate kinase, WW and PDZ domain containing 2 (MAGI2) gene (rs6959961, P = 2.61 × 10-7). A PPS created from the 12 lead SNPs was unable to predict V̇O2peak response in a tenfold cross validation, or in an independent (n = 39) validation study (P > 0.1). Significant correlations were found for beta coefficients of variants in the Predict-HIIT (P < 1 × 10-4) and the validation study (P < × 10-6), indicating that general effects of the loci exist, and that with a higher statistical power, more significant genetic associations may become apparent. CONCLUSIONS: Ongoing research and validation of current and previous findings is needed to determine if genetics does play a large role in V̇O2peak response variance, and whether genomic predictors for V̇O2peak response trainability can inform evidence-based clinical practice. Trial registration Australian New Zealand Clinical Trials Registry (ANZCTR), Trial Id: ACTRN12618000501246, Date Registered: 06/04/2018, http://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=374601&isReview=true .


Subject(s)
Cardiorespiratory Fitness/physiology , Exercise/physiology , Genetic Variation , Genome-Wide Association Study , Adult , Aged , Cohort Studies , Female , Humans , Male , Middle Aged
11.
Psychol Med ; 50(8): 1233-1240, 2020 06.
Article in English | MEDLINE | ID: mdl-32404224

ABSTRACT

Increasing evidence suggests that circulating factors and immune dysfunction may contribute to the pathogenesis of schizophrenia. In particular, proinflammatory cytokines, complement and autoantibodies against CNS epitopes have recently been associated with psychosis. Related concepts in previous decades led to several clinical trials of dialysis and plasmapheresis as treatments for schizophrenia. These trials may have relevance for the current understanding of schizophrenia. We aimed to identify whether dialysis or plasmapheresis are beneficial interventions in schizophrenia. We conducted a systematic search in major electronic databases for high-quality studies (double-blinded randomised trials with sham controls) applying either haemodialysis or plasmapheresis as an intervention in patients with schizophrenia, published in English from the start of records until September 2018. We found nine studies meeting inclusion criteria, reporting on 105 patients in total who received either sham or active intervention. One out of eight studies reported a beneficial effect of haemodialysis on schizophrenia, one a detrimental effect and six no effect. The sole trial of plasmapheresis found it to be ineffective. Adverse events were reported in 23% of patients. Studies were at unclear or high risk of bias. It is unlikely that haemodialysis is a beneficial treatment in schizophrenia, although the studies were of small size and could not consider potential subgroups. Plasmapheresis was only addressed by one study and warrants further exploration as a treatment modality in schizophrenia.


Subject(s)
Plasmapheresis , Renal Dialysis/methods , Schizophrenia/therapy , Autoimmune Diseases/immunology , Bias , Humans , Randomized Controlled Trials as Topic , Renal Dialysis/adverse effects , Schizophrenia/immunology
12.
Epilepsy Behav ; 113: 107518, 2020 12.
Article in English | MEDLINE | ID: mdl-33217665

ABSTRACT

INTRODUCTION: It has been suggested for over 100 years that patterns of neurological symptoms and signs in functional neurological disorders may be shaped at a neural level by underlying ideas or preconceptions how neurological symptoms present. This study used experimental simulation to probe ideas about seizures in healthy volunteers, with a view to compare with features commonly observed in functional and epileptic seizure disorders. METHODS: Sixty healthy volunteers were instructed to simulate an epileptic seizure. The episodes were video-recorded and assessed by three qualified markers for the presence of clinical features commonly observed in functional seizures (FS), epileptic seizures, and syncope. RESULTS: Simulated seizures were hyperkinetic (83%), hypokinetic (7%), or staring (10%). Fifty-two percent had their eyes open and 45% eyes closed. Tremor was observed in 70%, while clonic jerking was only present in 17%. The majority of volunteers maintained a normal or floppy body posture. Head shaking side-to-side was observed in 38%, while guttural cries, stertorous breathing, tearfulness, and hyperventilation were absent in all volunteers. DISCUSSION: Our results suggest that simulated seizures not only resemble FS more closely than epileptic seizures but also show some important differences. Subjective seizure experiences in people with FS, not captured by this experimental simulation, remain a core determinant of semiology.


Subject(s)
Epilepsy , Mental Disorders , Electroencephalography , Humans , Seizures , Syncope
13.
J Card Surg ; 35(8): 1871-1876, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32652703

ABSTRACT

BACKGROUND AND AIM: Mitral valve (MV) surgeries create electrophysiological substrates that give rise to postoperative arrhythmias. MV surgical procedures have been associated with macro- and microreentrant arrhythmogenic circuits, as well as circuits involving the atrial roof. It is not well understood why such arrhythmias develop; therefore, the aim of this study was to describe clinical and procedure characteristics associated with atrial arrhythmias in patients with prior MV surgery. METHODS: This retrospective chart review evaluated patients who had prior MV surgery and ablation procedures for atrial tachycardia between 2014 and 2018 (n = 20). Patients were classified into those exhibiting typical atrial flutter or another atrial tachyarrhythmia. RESULTS: Within the 20 patient cases reviewed, 30 arrhythmias were documented. Two-thirds of arrhythmias were typical atrial flutter; the percent incidence of arrhythmias originating in the right atrial (RA) roof, around the right atriotomy scar, in the left atrium, and at the crista terminalis was 20%, 3%, 7%, and 7%, respectively. Nearly every case of RA roof flutter (n = 5/6) and most arrhythmias (n = 20/30) occurred in patients who had a transseptal approach during MV surgery. Voltage maps did not show clear differences in scarring between groups. CONCLUSION: Results from this study suggest that an arrhythmogenic substrate for RA roof tachycardias is generated by transseptal approaches for MV surgery. This substrate is not clearly related to a surgical scar. These data suggest that other approaches should be considered for MV surgeries. Additionally, more research is needed to determine the mechanism for this nonscar-related arrhythmia substrate.


Subject(s)
Arrhythmias, Cardiac/epidemiology , Mitral Valve/surgery , Postoperative Complications/epidemiology , Humans , Prevalence , Retrospective Studies
14.
Bioconjug Chem ; 30(6): 1702-1710, 2019 06 19.
Article in English | MEDLINE | ID: mdl-31083974

ABSTRACT

Antibody-drug conjugates utilize the antigen specificity of antibodies and the potency of chemotherapeutic and antibiotic drugs for targeted therapy. However, as cancers and bacteria evolve to resist the action of drugs, innovative controlled release methods must be engineered to deliver multidrug cocktails. In this work, we engineer lipoate-acid ligase A (LplA) acceptor peptide (LAP) tags into the constant heavy and light chain of a humanized Her2 targeted antibody, trastuzumab. These engineered LAP tags, along with the glutamine 295 (Q295) residue in the heavy chain, were used to generate orthogonally cleavable site-specific antibody conjugates via a one-pot chemoenzymatic ligation with microbial transglutaminase (mTG) and LplA. We demonstrate orthogonal cargo release from these dual-labeled antibody bioconjugates via matrix metalloproteinase-2 and cathepsin-B-mediated bond cleavage. To the best of our knowledge, this is the first demonstration of temporal control on dual-labeled antibody conjugates, and we believe this platform will allow for sequential release and cooperative drug combinations on a single antibody bioconjugate.


Subject(s)
Antineoplastic Agents, Immunological/chemistry , Immunoconjugates/chemistry , Trastuzumab/chemistry , Antineoplastic Agents, Immunological/pharmacokinetics , Cell Line, Tumor , Drug Liberation , Humans , Immunoconjugates/pharmacokinetics , Models, Molecular , Peptide Synthases/chemistry , Peptides/chemistry , Trastuzumab/pharmacokinetics
15.
Drug Metab Dispos ; 47(7): 724-731, 2019 07.
Article in English | MEDLINE | ID: mdl-31028057

ABSTRACT

Midazolam is a widely used index substrate for assessing effects of xenobiotics on CYP3A activity. A previous study involving human hepatocytes showed the primary route of midazolam metabolism, 1'-hydroxylation, shifted to N-glucuronidation in the presence of the CYP3A inhibitor ketoconazole, which may lead to an overprediction of the magnitude of a xenobiotic-midazolam interaction. Because ketoconazole is no longer recommended as a clinical CYP3A inhibitor, indinavir was selected as an alternate CYP3A inhibitor to evaluate the contribution of the N-glucuronidation pathway to midazolam metabolism. The effects of indinavir on midazolam 1'-hydroxylation and N-glucuronidation were first characterized in human-derived in vitro systems. Compared with vehicle, indinavir (10 µM) inhibited midazolam 1'-hydroxylation by recombinant CYP3A4, human liver microsomes, and high-CYP3A activity cryopreserved human hepatocytes by ≥70%; the IC50 obtained with hepatocytes (2.7 µM) was within reported human unbound indinavir Cmax (≤5 µM). Midazolam N-glucuronidation in hepatocytes increased in the presence of indinavir in both a concentration-dependent (1-33 µM) and time-dependent (0-4 hours) manner (by up to 2.5-fold), prompting assessment in human volunteers (n = 8). As predicted by these in vitro data, indinavir was a strong inhibitor of the 1'-hydroxylation pathway, decreasing the 1'-hydroxymidazolam/midazolam area under the plasma concentration versus time curve (AUC)0-12h ratio by 80%. Although not statistically significant, the midazolam N-glucuronide/midazolam AUC0-12h ratio increased by 40%, suggesting a shift to the N-glucuronidation pathway. The amount of midazolam N-glucuronide recovered in urine increased 4-fold but remained <10% of the oral midazolam dose (2.5 mg). A powered clinical study would clarify whether N-glucuronidation should be considered when assessing the magnitude of a xenobiotic-midazolam interaction.


Subject(s)
Cytochrome P-450 CYP3A Inhibitors/pharmacology , Glucuronides/metabolism , HIV Protease Inhibitors/pharmacology , Indinavir/pharmacology , Midazolam/pharmacokinetics , Cross-Over Studies , Drug Interactions , Female , Hepatocytes/metabolism , Humans , Hydroxylation , In Vitro Techniques , Male , Midazolam/blood , Midazolam/urine , Prospective Studies
16.
Muscle Nerve ; 60(5): 513-519, 2019 11.
Article in English | MEDLINE | ID: mdl-31397910

ABSTRACT

BACKGROUND: Our pilot study tested the feasibility and performance of an eye-controlled power wheelchair for amyotrophic lateral sclerosis (ALS) patients. METHODS: In this prospective pilot study, participants drove the wheelchair three times around an indoor course. We assessed the time to complete the course; starting and stopping on command; turning 90, 135, and 180 degrees; time to backup; and obstacle negotiation. Following their use of the wheelchair, subjects were given a questionnaire to assess user experience. RESULTS: Twelve patients participated, and all were able to complete three trials without difficulty. Eight participants completed all of the individual tasks (eg, turning, stopping, etc.) without any errors. Overall performance ratings were high across all participants (4.6/5-excellent). CONCLUSIONS: Our eye-controlled power wheelchair prototype is feasible and has a very favorable user experience. This system has the potential to improve the mobility and independence of ALS patients, and other groups with motor impairments.


Subject(s)
Amyotrophic Lateral Sclerosis/rehabilitation , Equipment Design , Eye Movements , Patient Satisfaction , Wheelchairs , Adult , Aged , Feasibility Studies , Female , Humans , Male , Middle Aged , Pilot Projects , Prospective Studies
17.
Biol Blood Marrow Transplant ; 24(10): 2094-2100, 2018 10.
Article in English | MEDLINE | ID: mdl-29753836

ABSTRACT

We previously demonstrated a lower rate of cytomegalovirus (CMV) reactivation and disease among seropositive umbilical cord blood transplantation (CBT) recipients receiving an intensive prophylaxis strategy consisting of ganciclovir on days -8 to -2 pretransplantation, high-dose valacyclovir post-transplantation, and twice-weekly serum CMV polymerase chain reaction testing. We hypothesized that a modified intensive strategy excluding pretransplantation ganciclovir would be similarly effective. We compared the risk of CMV reactivation, occurrence of CMV disease, and duration of anti-CMV therapy by day 100 post-CBT in patients receiving the modified intensive and intensive strategies. Forty patients received the modified intensive strategy, and 43 received the intensive strategy. There was no difference in the hazard for CMV reactivation (hazard ratio, 1.1; P = .77). No patients in the modified intensive cohort, but 2 patients in the intensive cohort, developed CMV disease (P = .53). There was no difference in the hazard for early (≤30 days post-CBT; P = .76) or high-level (>1000 IU/mL; P = .37) CMV reactivation. Patients in the modified intensive cohort had marginally higher CMV viral loads and percentage of days of CMV detection and treatment, although the contribution of pretransplantation ganciclovir to these differences is unclear. The overall percentage of treatment days was 32% in both cohorts after accounting for pretransplantation ganciclovir. In conclusion, exclusion of prophylactic ganciclovir before CBT did not impact the risk of CMV reactivation or disease, although CMV kinetics appeared to differ by prevention strategy. Best practices for CMV prevention will need further study as new prophylactic strategies become available.


Subject(s)
Cord Blood Stem Cell Transplantation , Cytomegalovirus Infections/prevention & control , Cytomegalovirus , Ganciclovir/administration & dosage , Adolescent , Adult , Allografts , Child , Cytomegalovirus Infections/etiology , Female , Humans , Male , Middle Aged
18.
Biol Blood Marrow Transplant ; 23(3): 412-419, 2017 Mar.
Article in English | MEDLINE | ID: mdl-28007666

ABSTRACT

Cord blood transplantation (CBT) recipients are at increased risk for delayed engraftment and primary graft failure, complications that are often indistinguishable early post-transplantation. Current assays fail to accurately identify recipients with slow hematopoietic recovery and distinguish them from those with pending graft failure. To address this, we prospectively examined the kinetics of immune cell subset recovery in the peripheral blood of 39 patients on days +7 and +14 after double-unit CBT (dCBT) by multiparametric flow cytometry analysis, which we term real-time immunophenotyping (RTIP). RTIP analysis at day +14 revealed distinctive patterns of reconstitution and, importantly, identified patients with slow hematopoietic recovery who went on to engraft. Strikingly, higher absolute numbers of circulating monocytes and natural killer cells at day +14 were predictive of engraftment, but only the absolute number of circulating monocytes was significantly correlated with time to engraftment. This is the first evidence that RTIP on patient peripheral blood mononuclear cells early after dCBT is technically feasible and can be used as a "signature" for predicting the kinetics of hematopoietic recovery. Furthermore, RTIP is a time- and cost-efficient methodology that has the potential to become a clinically feasible diagnostic tool to guide therapeutic interventions in high-risk patients; therefore, its utility should be evaluated in a large cohort of patients.


Subject(s)
Cord Blood Stem Cell Transplantation/methods , Graft Survival , Immunophenotyping , Leukocytes/cytology , Adolescent , Adult , Child , Cord Blood Stem Cell Transplantation/standards , Delayed Graft Function , Female , Flow Cytometry , Humans , Kinetics , Leukocytes/immunology , Leukocytes, Mononuclear/cytology , Leukocytes, Mononuclear/immunology , Male , Middle Aged , Prognosis , Prospective Studies , Young Adult
19.
Am J Physiol Regul Integr Comp Physiol ; 306(8): R519-26, 2014 Apr 15.
Article in English | MEDLINE | ID: mdl-24523346

ABSTRACT

Diets high in sugar and saturated fat (Western diet) contribute to obesity and pathophysiology of metabolic syndrome. A common physiological response to obesity is hypertension, which induces cardiac remodeling and hypertrophy. Hypertrophy is regulated at the level of chromatin by repressor element 1-silencing transcription factor (REST), and pathological hypertrophy is associated with reexpression of a fetal cardiac gene program. Reactivation of fetal genes is commonly observed in hypertension-induced hypertrophy; however, this response is blunted in diabetic hearts, partially due to upregulation of the posttranslational modification O-linked-ß-N-acetylglucosamine (O-GlcNAc) to proteins by O-GlcNAc transferase (OGT). OGT and O-GlcNAc are found in chromatin-modifying complexes, but it is unknown whether they play a role in Western diet-induced hypertrophic remodeling. Therefore, we investigated the interactions between O-GlcNAc, OGT, and the fetal gene-regulating transcription factor complex REST/mammalian switch-independent 3A/histone deacetylase (HDAC). Five-week-old male C57BL/6 mice were fed a Western (n = 12) or control diet (n = 12) for 2 wk to examine the early hypertrophic response. Western diet-fed mice exhibited fasting hyperglycemia and increased body weight (P < 0.05). As expected for this short duration of feeding, cardiac hypertrophy was not yet evident. We found that REST is O-GlcNAcylated and physically interacts with OGT in mouse hearts. Western blot analysis showed that HDAC protein levels were not different between groups; however, relative to controls, Western diet hearts showed increased REST and decreased ANP and skeletal α-actin. Transcript levels of HDAC2 and cardiac α-actin were decreased in Western diet hearts. These data suggest that REST coordinates regulation of diet-induced hypertrophy at the level of chromatin.


Subject(s)
Diet, High-Fat , Gene Expression Regulation , Myocytes, Cardiac/metabolism , Actins/genetics , Actins/metabolism , Animals , Cardiomegaly/genetics , Cardiomegaly/metabolism , Gene Expression Regulation/physiology , Male , Mice , Mice, Inbred C57BL , Myocytes, Cardiac/pathology , N-Acetylglucosaminyltransferases/genetics , N-Acetylglucosaminyltransferases/metabolism , Obesity/genetics , Obesity/metabolism , Protein Processing, Post-Translational/physiology , Transcriptional Activation/genetics
20.
Cardiovasc Diabetol ; 12: 101, 2013 Jul 09.
Article in English | MEDLINE | ID: mdl-23835259

ABSTRACT

BACKGROUND: Exercise causes physiological cardiac hypertrophy and benefits the diabetic heart. Mammalian switch-independent 3A (mSin3A) and histone deacetylases (HDACs) 1 and 2 regulate hypertrophic genes through associations with the DNA binding proteins repressor element-1 silencing transcription factor (REST) and O-linked ß-N-acetylglucosamine transferase (OGT). O-linked ß-N-acetylglucosamine (O-GlcNAc) is a glucose derivative that is chronically elevated in diabetic hearts, and a previous study showed that exercise reduces cardiac O-GlcNAc. We hypothesized that O-GlcNAc and OGT would physically associate with mSin3A/HDAC1/2 in the heart, and that this interaction would be altered by diabetes and exercise. METHODS: 8-week-old type 2 diabetic db/db (db) and non-diabetic C57 mice were randomized to treadmill exercise or sedentary groups for 1 or 4 weeks. RESULTS: O-GlcNAc was significantly higher in db hearts and increased with exercise. Db hearts showed lower levels of mSin3A, HDAC1, and HDAC2 protein, but higher levels of HDAC2 mRNA and HDAC1/2 deacetylase activity. Elevated HDAC activity was associated with significantly blunted expression of α-actin and brain natriuretic peptide in db hearts. In sedentary db hearts, co-immunoprecipitation assays showed that mSin3A and OGT were less associated with HDAC1 and HDAC2, respectively, compared to sedentary C57 controls; however, exercise removed these differences. CONCLUSIONS: These data indicate that diabetes and exercise oppositely affect interactions between pro-hypertrophic transcription factors, and suggest that an increase in total cardiac O-GlcNAc is a mechanism by which exercise benefits type 2 diabetic hearts.


Subject(s)
Acetylglucosamine/metabolism , Diabetes Mellitus, Type 2/therapy , Diabetic Cardiomyopathies/therapy , Exercise Therapy , Histone Deacetylase 1/metabolism , Histone Deacetylase 2/metabolism , Myocardium/metabolism , Repressor Proteins/metabolism , Animals , Blood Glucose/metabolism , Cardiomegaly/metabolism , Cardiomegaly/therapy , Diabetes Mellitus, Type 2/diagnosis , Diabetes Mellitus, Type 2/genetics , Diabetes Mellitus, Type 2/metabolism , Diabetic Cardiomyopathies/diagnosis , Diabetic Cardiomyopathies/genetics , Diabetic Cardiomyopathies/metabolism , Disease Models, Animal , Gene Expression Regulation , Glycosylation , Histone Deacetylase 1/genetics , Histone Deacetylase 2/genetics , Mice, Inbred C57BL , N-Acetylglucosaminyltransferases/metabolism , Obesity/metabolism , Obesity/therapy , Protein Processing, Post-Translational , RNA, Messenger/metabolism , Repressor Proteins/genetics , Running , Sedentary Behavior , Sin3 Histone Deacetylase and Corepressor Complex , Time Factors
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