Publications by authors named "Matthew Halquist"

The development of highly potent and selective μ opioid receptor (MOR) modulators with favorable drug-like properties has always been a focus in the opioid domain. Our previous efforts led to the discovery of a lead compound designated as NAT, a potent centrally acting MOR modulator. However, the fact that NAT precipitated considerable withdrawal effects at higher doses largely impaired its further development.

View Article and Find Full Text PDF

High-risk (HR) corneal transplantation presents a formidable challenge, with over 50% of grafts experiencing rejection despite intensive postoperative care involving frequent topical eyedrop administration up to every 2 h, gradually tapering over 6-12 months, and ongoing maintenance dosing. While clinical evidence underscores the potential benefits of inhibiting postoperative angiogenesis, effective antiangiogenesis therapy remains elusive in this context. Here, we engineered controlled-release nanomedicine formulations comprising immunosuppressants (nanoparticles) and antiangiogenesis drugs (nanowafer) and demonstrated that these formulations can prevent HR corneal transplantation rejection for at least 6 months in a clinically relevant rat model.

View Article and Find Full Text PDF

Despite the availability of numerous pain medications, the current array of Food and Drug Administration-approved options falls short in adequately addressing pain states for numerous patients and consequently worsens the opioid crisis. Thus, it is imperative for basic research to develop novel and nonaddictive pain medications. Toward addressing this clinical goal, nalfurafine (NLF) was chosen as a lead and its structure-activity relationship (SAR) systematically studied through design, syntheses, and characterization of 24 analogues.

View Article and Find Full Text PDF

Studies have evaluated vitamin D's therapeutic potential in estrogen-responsive cancers, with conflicting findings. We have shown that the proliferation of breast cancer cells is regulated by 24R,25-dihydroxyvitamin D (24R,25(OH)D) depending on estrogen receptor alpha 66 (ERα66) expression, suggesting that this could also be the case for estrogen-sensitive laryngeal cancer cells. Accordingly, we examined levels of ERα isoforms in ERα66-positive UM-SCC-12 and ERα66-negative UM-SCC-11A cells and their response to 24R,25(OH)D.

View Article and Find Full Text PDF

Hepatic xenobiotic metabolism and transport decline with age, while intact xenobiotic metabolism is associated with longevity. However, few studies have examined the genome-wide impact of epigenetic aging on these processes. We used reduced representation bisulfite sequencing (RRBS) to map DNA methylation changes in liver DNA from mice ages 4 and 24 months.

View Article and Find Full Text PDF

While agonists of mu (MOR) and kappa (KOR) opioid receptors have analgesic effects, they produce euphoria and dysphoria, respectively. Other side effects include respiratory depression and addiction for MOR agonists and sedation for KOR agonists. We reported that 17-cyclopropylmethyl-3,14β-dihydroxy-4,5α-epoxy-6β-{[4'-(2'-cyanopyridyl)]carboxamido}cmorphinan (NCP) displayed potent KOR full agonist and MOR partial agonist activities (58%) with 6.

View Article and Find Full Text PDF

Ketone ester ((R)-3-hydroxybutyl (R)-3-hydroxybutyrate) has gained popularity as an exogenous means to achieve ketosis. Regarding its potential as a therapeutic prodrug, it will be necessary to study its pharmacokinetic profile and its proximal metabolites (beta-hydroxybutyrate, 1,3-butanediol, and acetoacetate) in humans. Here we develop and validate two LC-MS methods for quantifying KE and its metabolites in human plasma.

View Article and Find Full Text PDF

To characterize a molecularly imprinted polymer via precipitation polymerization for the extraction of cotinine in urine. The polymer was created via precipitation polymerization. Physical characteristics of the polymer were assessed via scanning electron microscopy, Fourier transform infrared spectroscopy and thermogravimetric analysis.

View Article and Find Full Text PDF

The role of vitamin D and its metabolites in cancer and especially as a treatment option has been widely disputed. Clinicians noting low serum 25-hydroxyvitamin D [25(OH)D] levels in their patients, recommend vitamin D supplementation as a method of reducing the risk of cancer; however, data supporting this are inconsistent. These studies rely on systemic 25(OH)D as an indicator of hormone status, but 25(OH)D is further metabolized in the kidney and other tissues under regulation by several factors.

View Article and Find Full Text PDF

Currently it is not fully understood how the device settings and electronic liquid (e-liquid) composition, including their form of nicotine content, impact mouth and throat losses, and potentially lead to the variations in total nicotine delivery to the human lungs. An size assessment method was developed for real-time measurements at the mouthpiece and outlet of a biorelevant mouth-throat to account for the dynamic nature of the aerosol. The aerosol size, temperature, and delivery through the mouth-throat replica and the exhaled aerosol between the puff intervals were measured at different wattages using various e-liquid compositions.

View Article and Find Full Text PDF

The U.S. Food and Drug Administration proposed new product standards that would ban characterizing flavors (other than tobacco) in cigars.

View Article and Find Full Text PDF

Eutectic mixtures can be formed by adding drugs other than nicotine (DOTNs) to nicotine-based e-liquids in electronic cigarettes (e-cigarettes). Thus, the interaction between nicotine e-liquids and DOTNs must be evaluated. Presented is the change in e-cigarette aerosolization of nicotine and methadone alone versus a 1:1 nicotine:methadone mixture to evaluate the possible formation of a eutectic mixture that can result in an increase of drug delivery.

View Article and Find Full Text PDF

With the ever-growing abundance of complex therapeutic proteins reaching clinical trials and post-marketing, it is vital to develop highly accurate and robust bioanalytical methods for their quantitative analysis in matrices, to support clinical trial data as well as therapeutic drug monitoring. In bioanalysis, proteins have traditionally been evaluated using ligand binding assays (LBAs). However, in recent years, bottom-up LC-MS/MS methods have begun to gain recognition as an alternative to LBAs in situations where either there is a desire to reduce lengthy development times, or where selectivity issues prevent the immunoassay from reaching the desired outcome.

View Article and Find Full Text PDF

Ranibizumab is an FDA-approved drug used to treat wet age-related macular degeneration (AMD), diabetic retinopathy, macular edema, and myopic choroidal neovascularization. Bevacizumab is another drug often used off-label to treat wet AMD. In order to reduce unwanted angiogenesis, ranibizumab and bevacizumab target circulating VEGF-A in the eye.

View Article and Find Full Text PDF

Molecularly imprinted polymers (MIPs) are synthetic polymers designed to selectively extract target analytes from complex matrices (including biological matrices). The literature shows that MIPs have a degree of cross-selectivity from analytes within the same class of compounds. A commercially available MIP for tobacco-specific nitrosamines (TSNAs) is designed to be class selective for four TSNA compounds.

View Article and Find Full Text PDF

The μ opioid receptor (MOR) has been an intrinsic target to develop treatment of opioid use disorders (OUD). Herein, we report our efforts on developing centrally acting MOR antagonists by structural modifications of 17-cyclopropylmethyl-3,14-dihydroxy-4,5α-epoxy-6β-[(4'-pyridyl) carboxamido] morphinan (NAP), a peripherally acting MOR-selective antagonist. An isosteric replacement concept was applied and incorporated with physiochemical property predictions in the molecular design.

View Article and Find Full Text PDF

Electronic cigarettes are available in a variety of devices with e-liquids also available in many flavors, and nicotine concentrations, albeit less than 20 mg/mL in Europe. Given the dynamics of these products, it is important to evaluate product content, including labeling, nicotine content versus labeled claim, nicotine form, and other aspects that may help policy decisions and align with the Tobacco Product Directive (TPD). Herein, we performed a study on 86 e-liquids from seven European countries (Croatia, Czech Republic, France, Germany, Italy, Poland, and the United Kingdom) with 34 different liquid brands and 57 different flavors.

View Article and Find Full Text PDF

Tobacco specific nitrosamines (TSNAs) are highly carcinogenic by-products in tobacco samples, and their presence is regulated by the Food and Drug Administration. Molecularly imprinted polymers (MIPs) are synthetic polymers that have been "imprinted" with a template analyte in a co-polymer system, and can selectively extract analytes from complex matrices. MIPs can be incorporated into online systems, replacing traditional high performance liquid chromatography (HPLC) columns.

View Article and Find Full Text PDF

Objectives: Phase II drug metabolism is poorly studied in advanced age and older adults may exhibit significant variability in their expression of phase II enzymes. We hypothesized that age-related changes to epigenetic regulation of genes involved in phase II drug metabolism may contribute to these effects.

Methods: We examined published epigenome-wide studies of human blood and identified the SULT1A1 and UGT1A6 genes as the top loci showing epigenetic changes with age.

View Article and Find Full Text PDF

Background: Endogenous serine protease inhibitors are associated with anti-inflammatory and pro-survival signaling mediated via Low-density lipoprotein receptor-related protein 1 (LRP1) signaling. SP16 is a short polypeptide that mimics the LRP1 binding portion of alpha-1 antitrypsin.

Methods: A pilot phase I, first-in-man, randomized, double blind, placebo-controlled safety study was conducted to evaluate a subcutaneous injection at three dose levels of SP16 (0.

View Article and Find Full Text PDF

Introduction: Adolescents are at increased risk of secondhand smoke exposure (SHS) due to the limited control that they have over social and physical environments. Yet, knowledge regarding determinants of SHS among non-smoking adolescents is limited. This study identifies social and environmental factors associated with SHS among non-smoking adolescents.

View Article and Find Full Text PDF

The complexity of Tobradex® ointment formulation (dexamethasone 0.1 wt% and tobramycin 0.3 wt%) and the high cost of pharmacokinetic (PK) studies in human aqueous humor may prevent generic drug companies from moving forward with a Tobradex®-equivalent product development.

View Article and Find Full Text PDF

Background: The free base and protonated nicotine forms in e-cigarette aerosol have shown different absorption profiles in users. Therefore, it is also important to identify the factors which can affect the ratio of these nicotine forms in the aerosol. Such factors may include nicotine concentrations, flavors, PG:VG ratios, types of nicotine chemical compounds and e-cigarette battery power outputs.

View Article and Find Full Text PDF

As biologic based drugs become an increasingly important sector of the pharmaceutical industry, accurate and precision techniques for bioanalysis are required to support clinical trials and beyond. Ranibizumab, a fab therapeutic, is an FDA approved drug to treat wet age-related macular degeneration (AMD), as well as other eye related diseases. Ranibizumab's mAb counterpart, bevacizumab, is often also used off-label to treat wet AMD.

View Article and Find Full Text PDF

A PHP Error was encountered

Severity: Warning

Message: fopen(/var/lib/php/sessions/ci_sessionjv0gfqeg7u04bppghp0vhlhv1nhdbq7k): Failed to open stream: No space left on device

Filename: drivers/Session_files_driver.php

Line Number: 177

Backtrace:

File: /var/www/html/index.php
Line: 316
Function: require_once

A PHP Error was encountered

Severity: Warning

Message: session_start(): Failed to read session data: user (path: /var/lib/php/sessions)

Filename: Session/Session.php

Line Number: 137

Backtrace:

File: /var/www/html/index.php
Line: 316
Function: require_once