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1.
J Asthma ; 59(11): 2305-2313, 2022 Nov.
Article in English | MEDLINE | ID: mdl-34806541

ABSTRACT

INTRODUCTION: Both the National Heart, Lung, and Blood Institute (NHLBI) and Global Initiative for Asthma (GINA) asthma practice guidelines recommend that providers routinely check inhaler technique and correct any mistakes that patients may make when using these devices. Providers, however, rarely check inhaler technique during asthma visits. The objectives of this study were to: (1) describe the development of an instrument to measure self-efficacy and outcome expectations regarding inhaler technique patient education, (2) evaluate the internal consistency reliability of the new scales, and (3) provide preliminary evidence of construct validity. Methods: First- and second-year physician assistant (PA) students at two institutions completed an anonymous and voluntary survey evaluating two new instruments, the Teaching Inhalers to Patients: Self-efficacy (TIP-SE) and the Teaching Inhalers to Patients: Outcome Expectations (TIP-OE) scales and sociodemographic characteristics. The data were analyzed using Principal Components Analysis (PCA), Cronbach's α, and multivariable logistic regression. Results: We had usable responses from 146 PA students (71.9% participation rate). The PCA identified one factor for the TIP-SE and TIP-OE, respectively. The internal consistency of the TIP-SE and TIP-OE was α = 0.96 and α = 0.92, respectively. The logistic regression found that second-year PA students who had higher mean TIP-SE scores were significantly more likely to report teaching patients to use inhalers during rotations (OR = 1.8, 95% CI = 1.1, 2.9). There was not a statistically significant relationship between reporting teaching patients to use inhalers during rotations and mean TIP-OE scores. Conclusion: The TIP-SE and TIP-OE show preliminary evidence of reliability and validity.Supplemental data for this article is available online at https://doi.org/10.1080/02770903.2021.2008428 .


Subject(s)
Asthma , Administration, Inhalation , Asthma/drug therapy , Humans , Metered Dose Inhalers , Motivation , Nebulizers and Vaporizers , Psychometrics , Reproducibility of Results , Self Efficacy
2.
ACS Appl Mater Interfaces ; 13(40): 47418-47439, 2021 Oct 13.
Article in English | MEDLINE | ID: mdl-34608803

ABSTRACT

We present a potential solution to the problem of extraction of photogenerated holes from CdS nanocrystals and nanowires. The nanosheet form of C3N5 is a low-band-gap (Eg = 2.03 eV), azo-linked graphenic carbon nitride framework formed by the polymerization of melem hydrazine (MHP). C3N5 nanosheets were either wrapped around CdS nanorods (NRs) following the synthesis of pristine chalcogenide or intercalated among them by an in situ synthesis protocol to form two kinds of heterostructures, CdS-MHP and CdS-MHPINS, respectively. CdS-MHP improved the photocatalytic degradation rate of 4-nitrophenol by nearly an order of magnitude in comparison to bare CdS NRs. CdS-MHP also enhanced the sunlight-driven photocatalytic activity of bare CdS NWs for the decolorization of rhodamine B (RhB) by a remarkable 300% through the improved extraction and utilization of photogenerated holes due to surface passivation. More interestingly, CdS-MHP provided reaction pathway control over RhB degradation. In the absence of scavengers, CdS-MHP degraded RhB through the N-deethylation pathway. When either hole scavenger or electron scavenger was added to the RhB solution, the photocatalytic activity of CdS-MHP remained mostly unchanged, while the degradation mechanism shifted to the chromophore cleavage (cycloreversion) pathway. We investigated the optoelectronic properties of CdS-C3N5 heterojunctions using density functional theory (DFT) simulations, finite difference time domain (FDTD) simulations, time-resolved terahertz spectroscopy (TRTS), and photoconductivity measurements. TRTS indicated high carrier mobilities >450 cm2 V-1 s-1 and carrier relaxation times >60 ps for CdS-MHP, while CdS-MHPINS exhibited much lower mobilities <150 cm2 V-1 s-1 and short carrier relaxation times <20 ps. Hysteresis in the photoconductive J-V characteristics of CdS NWs disappeared in CdS-MHP, confirming surface passivation. Dispersion-corrected DFT simulations indicated a delocalized HOMO and a LUMO localized on C3N5 in CdS-MHP. C3N5, with its extended π-conjugation and low band gap, can function as a shuttle to extract carriers and excitons in nanostructured heterojunctions, and enhance performance in optoelectronic devices. Our results demonstrate how carrier dynamics in core-shell heterostructures can be manipulated to achieve control over the reaction mechanism in photocatalysis.

3.
Adv Mater ; 33(34): e2100978, 2021 Aug.
Article in English | MEDLINE | ID: mdl-34278600

ABSTRACT

Tin iodide phosphide (SnIP), an inorganic double-helix material, is a quasi-1D van der Waals semiconductor that shows promise in photocatalysis and flexible electronics. However, the understanding of the fundamental photophysics and charge transport dynamics of this new material is limited. Here, time-resolved terahertz (THz) spectroscopy is used to probe the transient photoconductivity of SnIP nanowire films and measure the carrier mobility. With insight into the highly anisotropic electronic structure from quantum chemical calculations, an electron mobility as high as 280 cm2 V-1 s-1 along the double-helix axis and a hole mobility of 238 cm2 V-1 s-1 perpendicular to the double-helix axis are detected. Additionally, infrared-active (IR-active) THz vibrational modes are measured, which shows excellent agreement with first-principles calculations, and an ultrafast photoexcitation-induced charge redistribution is observed that reduces the amplitude of a twisting mode of the outer SnI helix on picosecond timescales. Finally, it is shown that the carrier lifetime and mobility are limited by a trap density greater than 1018 cm-3 . The results provide insight into the optical excitation and relaxation pathways of SnIP and demonstrate a remarkably high carrier mobility for such a soft and flexible material, suggesting that it could be ideally suited for flexible electronics applications.

4.
J Pharmacol Exp Ther ; 308(2): 410-8, 2004 Feb.
Article in English | MEDLINE | ID: mdl-14610241

ABSTRACT

In the studies reported here, the ability of atomoxetine hydrochloride (Strattera) to inhibit or induce the metabolic capabilities of selected human isoforms of cytochrome P450 was evaluated. Initially, the potential of atomoxetine and its two metabolites, N-desmethylatomoxetine and 4-hydroxyatomoxetine, to inhibit the metabolism of probe substrates for CYP1A2, CYP2C9, CYP2D6, and CYP3A was evaluated in human hepatic microsomes. Although little inhibition of CYP1A2 and CYP2C9 activity was observed, inhibition was predicted for CYP3A (56% predicted inhibition) and CYP2D6 (60% predicted inhibition) at concentrations representative of high therapeutic doses of atomoxetine. The ability of atomoxetine to induce the catalytic activities of CYP1A2 and CYP3A in human hepatocytes was also evaluated; however, atomoxetine did not induce either isoenzyme. Based on the potential of interaction from the in vitro experiments, drug interaction studies in healthy subjects were conducted using probe substrates for CYP2D6 (desipramine) in CYP2D6 extensive metabolizer subjects and CYP3A (midazolam) in CYP2D6 poor metabolizer subjects. Single-dose pharmacokinetic parameters of desipramine (single dose of 50 mg) were not altered when coadministered with atomoxetine (40 or 60 mg b.i.d. for 13 days). Only modest changes (approximately 16%) were observed in the plasma pharmacokinetics of midazolam (single dose of 5 mg) when coadministered with atomoxetine (60 mg b.i.d. for 12 days). Although at high therapeutic doses of atomoxetine inhibition of CYP2D6 and CYP3A was predicted, definitive in vivo studies clearly indicate that atomoxetine administration with substrates of CYP2D6 and CYP3A does not result in clinically significant drug interactions.


Subject(s)
Aryl Hydrocarbon Hydroxylases/metabolism , Cytochrome P-450 CYP1A2/metabolism , Cytochrome P-450 CYP2D6/metabolism , Microsomes, Liver/metabolism , Propylamines/metabolism , Atomoxetine Hydrochloride , Cytochrome P-450 CYP2C9 , Diclofenac/metabolism , Drug Interactions , Ethanolamines/metabolism , Humans , Hydroxylation , Microsomes, Liver/enzymology , Midazolam/metabolism , Phenacetin/metabolism
5.
J Appl Toxicol ; 23(5): 301-14, 2003.
Article in English | MEDLINE | ID: mdl-12975769

ABSTRACT

Ethylene glycol monohexyl ether (EGHE; CAS no. 112-54-4) is a liquid industrial chemical with a potential for skin contact. The toxicokinetics of EGHE was investigated in Fischer 344 rats and New Zealand White rabbits by intravenous (i.v.) and 48-h occluded epicutaneous dosing. Given i.v. to male rats (2.5-25 mg kg(-1)) [(14)C]EGHE demonstrated fi rst-order kinetics. Carbon-14 was eliminated mainly in urine (68-74%) as metabolites, with no free EGHE. The plasma free EGHE concentration declined rapidly post-dosing and was not detectable by 8 h. Similar results were obtained for [(14)C]EGHE given i.v. to male rabbits in the dosage range 1-10 mg kg(-1), except that the metabolism of EGHE was more rapid, with no free EGHE being detectable in plasma by 1 h post-dosing. After cutaneous dosing of male and female rats with 25 mg kg(-1), there was rapid percutaneous absorption, with >95% of the radiochemical dose being recovered. Percutaneous bioavailability was >75%. Carbon-14 was excreted in urine (21-33%) to a lesser extent than by the i.v. route, and (14)CO(2) and volatiles accounted for 15-18%. Carbon-14 recovery was low from tissues and organs (0.39-0.46%), with no preferential accumulation. Extensive metabolism was indicated by the rapid decline in plasma free EGHE, with none being detectable by 48 h. Free EGHE was not present in urine, and urinary radioactivity was associated with up to seven metabolites. After cutaneous dosing of male and female rabbits (10 mg kg(-1)) ca. 75% of the dose was recovered, most (14)C being in urine (58-60%). Urine radioactivity was associated with up to nine metabolite peaks, but no free EGHE. The toxicokinetic findings indicate a significant percutaneous absorption of EGHE across both rat and rabbit skin, which is rapidly and extensively metabolized, with renal excretion being the principal route of elimination of metabolites. A 9-day repeated skin contact study in the male and female New Zealand White rabbit, using a dosage range of 44-444 mg kg(-1) day(-1), did not show any evidence for percutaneous systemic toxicity.


Subject(s)
Ethylene Glycols/pharmacokinetics , Ethylene Glycols/toxicity , Administration, Cutaneous , Animals , Area Under Curve , Body Weight , Carbon Radioisotopes , Dose-Response Relationship, Drug , Edema/chemically induced , Erythema/chemically induced , Ethylene Glycols/administration & dosage , Female , Half-Life , Injections, Intravenous , Male , Metabolic Clearance Rate , Rabbits , Rats , Rats, Inbred F344 , Sex Factors , Skin Absorption , Species Specificity , Time Factors
6.
Chem Res Toxicol ; 16(7): 912-9, 2003 Jul.
Article in English | MEDLINE | ID: mdl-12870894

ABSTRACT

Dark liver pigmentation was observed in F344 rats in a subchronic toxicology study after daily dosing of LY368842 glycolate. In addition, green-colored urine was observed in some animals. To identify the source of the pigment and its potential for toxic consequences, the liver pigment was isolated from the liver tissue of rats. The resulting material was a dark brown to black powder that was insoluble in water, organic solvents, or a tissue-solubilizing agent. Several techniques, such as chemical degradation, HPLC, tandem mass spectrometry (LC/MS/MS), (1)H NMR, and matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS), were employed to characterize the dark liver pigment. Following oxidative degradation of the isolated pigment, degradation products related to LY368842 were identified or tentatively identified using LC/MS/MS. Two degradation products had the same protonated molecular ion at m/z 505, which is 30 amu higher than that of LY368842. The major m/z 505 product has been identified as the indole-2,3-dione oxidative product based on (1)H NMR data and confirmed by an authentic standard. In addition, monohydroxylated product was also identified in the degradation mixture. These degradation products were consistent with the metabolites found in vivo in rats. MALDI-MS analyses of liver and urine pigment both identified a product with a protonated molecular ion at m/z 977, suggesting formation of indirubin-like and indigo-like pigments. The results obtained suggest that the oxidative metabolites of LY368842 played a key role in the formation of the liver and urine pigments.


Subject(s)
Adrenergic beta-3 Receptor Agonists , Adrenergic beta-Agonists/pharmacology , Indoles/antagonists & inhibitors , Liver/metabolism , Pigments, Biological/metabolism , Pyridines/antagonists & inhibitors , Animals , Isatin/analogs & derivatives , Isatin/analysis , Liver/chemistry , Liver/drug effects , Magnetic Resonance Spectroscopy , Mass Spectrometry , Molecular Structure , Oxidation-Reduction , Pigments, Biological/chemistry , Pigments, Biological/urine , Rats , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
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