Publications by authors named "David Hibbs"

Article Synopsis
  • * Halogen substitutions at the ortho position (chlorine and bromine) were found to decrease QY significantly, with values dropping from 70% for 7-hydroxycoumarin to 61% for ortho-chloro and 30% for ortho-bromo, indicating increased energy dissipation.
  • * The study suggests that the reductions in QY are influenced by factors beyond the heavy-atom effect, involving spin-orbit coupling effects that affect intersystem crossing and phosphorescence rates
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Objective: Androgen insensitivity syndrome (AIS) due to androgen receptor (AR) mutations creates a spectrum of clinical presentations based on residual AR function with the mildest impairment creating mild AIS (MAIS) whose undefined molecular mechanism and subtle clinical features leave it less understood and underdiagnosed.

Design: In silico modeling and in vitro androgen bioassay of the mutated AR are used to identify its structural and physiological mechanism. Clinical features and responses to high-dose testosterone treatment of three cases of MAIS across a six-generation family pedigree are described.

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Unlike small molecule drugs and generic products, the active component of biologics and biosimilars are not identical chemical entities. Despite bioequivalence, there is limited evidence in clinical practice (i.e.

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Background And Objectives: Saliva is a patient-friendly matrix for therapeutic drug monitoring (TDM) but is infrequently used in routine care. This is due to the uncertainty of saliva-based TDM results to inform dosing. This study aimed to retrieve data on saliva-plasma concentration and subsequently determine the physicochemical properties that influence the excretion of drugs into saliva to increase the foundational knowledge underpinning saliva-based TDM.

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Synthetic cannabinoid receptor agonists (SCRAs) comprise the second largest class of new psychoactive substances (NPS), and typically α-amino acid moieties are incorporated as part of their design. Limited investigation has been performed into elucidating structure-activity relationships around commonly used α-amino acid-derived head groups, mainly with valine and -leucine-derived compounds previously described. As such, proactive synthesis, characterisation and pharmacological evaluation were performed to explore structure-activity relationships of 15 α-amino acid derivatives, with both the natural isomers and their enantiomers at CB and CB investigated using a fluorescence-based membrane potential assay.

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Synthetic cannabinoid receptor agonists (SCRAs) are a growing class of new psychoactive substances (NPS) commonly derived from an -alkylated indole, indazole, or 7-azaindole scaffold. Diversification of this core (at the 3-position) with amide-linked pendant amino acid groups and modular -alkylation (of the indole/indazole/7-azaindole core) ensures that novel SCRAs continue to enter the illicit drug market rapidly. In response to the large number of SCRAs that have been detected, pharmacological evaluation of this NPS class has become increasingly common.

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Unlabelled: Candidiasis places a significant burden on human health and can range from common superficial vulvovaginal and oral infections to invasive diseases with high mortality. The most common species implicated in human disease is , but other species like are emerging. The use of azole antifungals for treatment is limited by increasing rates of resistance.

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ADB-HEXINACA has been recently reported as a synthetic cannabinoid receptor agonist (SCRA), one of the largest classes of new psychoactive substances (NPSs). This compound marks the entry of the -hexyl tail group into the SCRA landscape, which has continued in the market with recent, newly detected SCRAs. As such, a proactive characterization campaign was undertaken, including the synthesis, characterization, and pharmacological evaluation of ADB-HEXINACA and a library of 41 closely related analogues.

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Several classes of cannabinoid receptor type 2 radioligands have been evaluated for imaging of neuroinflammation, with successful clinical translation yet to take place. Here we describe the synthesis of fluorinated 5-azaindoles and pharmacological characterization and evaluation of F-radiolabeled analogues. [F] (hCB2 = 96.

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T-cell recognition of antigens is complex, leading to biochemical and cellular events that impart both specific and targeted immune responses. The end result is an array of cytokines that facilitate the direction and intensity of the immune reaction-such as T-cell proliferation, differentiation, macrophage activation, and B-cell isotype switching-all of which may be necessary and appropriate to eliminate the antigen and induce adaptive immunity. Using in silico docking to identify small molecules that putatively bind to the T-cell Cβ-FG loop, we have shown in vitro using an antigen presentation assay that T-cell signalling is altered.

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Here, we show that 3,5-bis[(1E)-2-(2,6-dichlorophenyl)ethenyl]-1H-pyrazole 2l depolymerizes microtubules and reduces the number of growing tips of microtubules. The fluorescence recovery after photobleaching experiment in live MCF-7 cells showed that pyrazole 2l suppresses spindle microtubule dynamics. Further, the compound inhibits chromosome movements, activates the spindle assembly checkpoint and blocks mitosis in MCF-7 cells.

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Article Synopsis
  • Synthetic anion transporters have shown promise in treating serious conditions like cystic fibrosis and cancer, but their design needs to consider solubility and how well they can be delivered in the body.
  • Researchers explored fluorinated versions of tetrapodal (thio)urea transporters to enhance their lipophilicity, solubility, and transport efficiency for anions through specific assays.
  • The most fluorinated variant demonstrated the best transport activity and exhibited a change in anion selectivity compared to earlier tripodal transporter designs, indicating a potential improvement in function.
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The drug discovery process is a rocky path that is full of challenges, with the result that very few candidates progress from hit compound to a commercially available product, often due to factors, such as poor binding affinity, off-target effects, or physicochemical properties, such as solubility or stability. This process is further complicated by high research and development costs and time requirements. It is thus important to optimise every step of the process in order to maximise the chances of success.

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Over 200 synthetic cannabinoid receptor agonists (SCRAs) have been identified as new psychoactive substances. Effective monitoring and characterization of SCRAs are hindered by the rapid pace of structural evolution. Ahead of possible appearance on the illicit drug market, new SCRAs were synthesized to complete a systematic library of cumyl-indole- (, CUMYL-CPrMICA, CUMYL-CPMICA) and cumyl-indazole-carboxamides (, CUMYL-CPrMINACA, CUMYL-CPMINACA), encompassing butyl, pentyl, cyclopropylmethyl, cyclobutylmethyl, cyclopentylmethyl, and cyclohexylmethyl tails.

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Context: The demand of palliative care is increasing due to the aging population and treatment hesitancy or intentional avoidance compromises symptom management.

Objectives: To identify patient beliefs associated with medication hesitancy by using the theory of planned behavior (TPB) namely, attitudes, subjective norms, behavioral intention, and perceived behavioral control associated with medication hesitancy or intentional noncompliance by avoidance.

Methods: The Preferred Reporting Items for Systematic Reviews and Meta-Analysis guideline was followed to conduct a systematic literature search involving the CINAHL, Embase, MEDLINE, and PsycINFO databases from inception until March 2022.

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Antibacterial resistance is a prominent issue with monotherapy often leading to treatment failure in serious infections. Many mechanisms can lead to antibacterial resistance including deactivation of antibacterial agents by bacterial enzymes. Enzymatic drug modification confers resistance to β-lactams, aminoglycosides, chloramphenicol, macrolides, isoniazid, rifamycins, fosfomycin and lincosamides.

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Multi-drug resistance is increasing in the pathogenic bacterium , which is mainly responsible for meningitis and community-acquired pneumonia (CAP), highlighting the need for new anti-pneumococcal agents. We have identified a potential anti-pneumococcal agent, enol , which acts by hindering the cell division process by perturbing Z-ring dynamics inside the cell. Enol was also shown to inhibit FtsZ polymerization and induce its aggregation in vitro but does not affect the activity of tubulin and alkaline phosphatase.

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Synthetic cannabinoid receptor agonists (SCRAs) continue to make up a significant portion new psychoactive substances (NPS) detected and seized worldwide. Due to their often potent activation of central cannabinoid receptors , use of SCRAs can result in severe intoxication, in addition to other adverse health effects. Recent detections of AB-4CN-BUTICA, MMB-4CN-BUTINACA, MDMB-4F-BUTICA and MDMB-4F-BUTINACA mark a continuation in the appearance of SCRAs bearing novel tail substituents.

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Article Synopsis
  • Theophylline (THEO) is a bronchodilator available in tablet and liquid forms but suffers from poor stability due to its hygroscopic nature, impacting its shelf-life as a medication.
  • * Researchers aimed to improve THEO's stability by creating a cocrystal with malonic acid (MA), but tests showed no significant improvement in the cocrystal's hygroscopic properties.
  • * High-resolution X-ray crystallography and Density Functional Theory analysis revealed that while the cocrystal has stable interactions, it does not significantly alter THEO's properties, indicating that returning to the original components (THEO and MA) is equally possible.
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  • This study focused on how adding 2-methylimidazole (2-MIM) affects the fluorescence of a specific compound called ethyl-7-hydroxy-2-oxo-2-chromene-3-carboxylate using low-cost computational methods and X-ray data.
  • It found that at low concentrations of 2-MIM, the fluorescence intensity decreases, but at higher concentrations (above 1:10), the excitation wavelength shifts and the emission intensity significantly increases due to deprotonation of a phenolic group in the compound.
  • The research also revealed that the interactions between 2-MIM and the fluorophore, specifically increased vibronic coupling and charge transfer, led to these fluorescence changes, alongside
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Synthetic cannabinoid receptor agonists (SCRAs) are a large and growing class of new psychoactive substances (NPSs). Two recently identified compounds, MEPIRAPIM and 5F-BEPIRAPIM (NNL-2), have not been confirmed as agonists of either cannabinoid receptor subtype but share structural similarities with both SCRAs and a class of T-type calcium channel (Ca3) inhibitors under development as new treatments for epilepsy and pain. In this study, MEPIRAPIM and 5F-BEPIRAPIM and 10 systematic analogues were synthesized, analytically characterized, and pharmacologically evaluated using cannabinoid receptor and Ca3 assays.

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Synthetic cannabinoid receptor agonists (SCRAs) are a diverse class of new psychoactive substances (NPS). They commonly comprise -alkylated indole, indazole, or 7-azaindole scaffolds with amide-linked pendant amino acid groups. To explore the contribution of the amino acid side chain to the cannabinoid pharmacology of SCRA NPS, a systematic library of side chain-modified SCRAs was prepared based on the recent detections of amino acid derivatives (5F-AB-PINACA), (5F-ADB-PINACA), (PX-1), (PX-2), and (NNL-1).

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Article Synopsis
  • * Researchers created a library of synthetic compounds related to newly detected drugs, studying their interaction and activity with cannabinoid receptors (CB1 and CB2).
  • * Findings showed that certain compounds had high binding affinity and acted as strong or partial agonists for these receptors, with ADB-BUTINACA and ADB-P7AICA displaying significant effects on body temperature in mice, while APP-BUTINACA did not.
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GABAϱ receptors are distinctive GABAergic receptors from other ionotropic GABA and metabotropic GABA receptors in their pharmacological, biochemical, and electrophysiological properties. Although GABA-ϱ1 receptors are the most studied in this subfamily, GABA-ϱ2 receptors are widely distributed in the brain and are considered a potential target for treating neurological disorders such as stroke. The structure of GABA-ϱ2 receptors and their pharmacological features are poorly studied.

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The orthosteric binding site of GABA-gated ion channels has been widely explored. Many residues in the binding site of GABA were studied. The interactions due to the binding of GABA into the binding site drive channel activation and determine the potency and efficacy of GABA response.

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