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1.
Chemistry ; 29(21): e202203730, 2023 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-36689256

RESUMEN

The development of potent H2 production catalysts is a key aspect in our journey toward the establishment of a sustainable carbon-neutral power infrastructure. Hydrogenase enzymes provide the blueprint for designing efficient catalysts by the rational combination of central metal core and protein scaffold-based outer coordination sphere (OCS). Traditionally, a biomimetic catalyst is crafted by including natural amino acids as OCS features around a synthetic metal motif to functionally imitate the metalloenzyme activity. Here, we have pursued an unconventional approach and implanted two distinct drug molecules (isoniazid and nicotine hydrazide) at the axial position of a cobalt core to create a new genre of synthetic catalysts. The resultant cobalt complexes are active for both electrocatalytic and photocatalytic H2 production in near-neutral water, where they significantly enhance the catalytic performance of the unfunctionalized parent cobalt complex. The drug molecules showcased a dual effect as they influence the catalytic HER by improving the surrounding proton relay along and exerting subtle electronic effects. The isoniazid-ligated catalyst C1 outperformed the nicotine hydrazide-bound complex C2, as it produced H2 from water (pH 6.0) at a rate of 3960 s-1 while exhibiting Faradaic efficiency of about 90 %. This strategy opens up newer avenues of bio-inspired catalyst design beyond amino acid-based OCS features.


Asunto(s)
Hidrógeno , Isoniazida , Hidrógeno/química , Protones , Aminoácidos/química , Metales , Cobalto/química , Agua
2.
POCUS J ; 7(1): 171-178, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36896274

RESUMEN

Purpose: To determine medical student ability to accurately obtain and interpret POCUS exams of varying difficulty in the pediatric population after a short didactic and hands-on POCUS course. Methods: Five medical students were trained in four POCUS applications (bladder volume, long bone for fracture, limited cardiac for left ventricular function, & inferior vena cava collapsibility) and enrolled pediatric ED patients. Ultrasound-fellowship-trained emergency medicine physicians reviewed each scan for image quality and interpretation accuracy using the American College of Emergency Physicians' quality assessment scale. We report acceptable scan frequency and medical student vs. Ultrasound-fellowship-trained emergency medicine physician interpretation agreement with 95% confidence intervals (CI). Results: Ultrasound-fellowship-trained emergency medicine physicians graded 51/53 bladder volume scans as acceptable (96.2%; 95% CI 87.3-99.0%) and agreed with 50/53 bladder volume calculations (94.3%; 95% CI 88.1-100%). Ultrasound-fellowship-trained emergency medicine physicians graded 35/37 long bone scans as acceptable (94.6%; 95% CI 82.3-98.5%) and agreed with 32/37 medical student long bone scan interpretations (86.5%; 95% CI 72.0-94.1%). Ultrasound-fellowship-trained emergency medicine physicians graded 116/120 cardiac scans as acceptable (96.7%; 95% CI 91.7-98.7%) and agreed with 111/120 medical student left ventricular function interpretations (92.5%; 95% CI 86.4-96.0%). Ultrasound-fellowship-trained emergency medicine physicians graded 99/117 inferior vena cava scans as acceptable (84.6%; 95% CI 77.0-90.0%) and agreed with 101/117 medical student interpretations of inferior vena cava collapsibility (86.3%; 95% CI 78.9-91.4%). Conclusions: Medical students demonstrated satisfactory ability within a short period of time in a range of POCUS scans on pediatric patients after a novel curriculum. This supports the incorporation of a formal POCUS education into medical school curricula and suggests that novice POCUS learners can attain a measure of competency in multiple applications after a short training course.

4.
RSC Adv ; 8(9): 4976-4978, 2018 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-35544427

RESUMEN

[This corrects the article DOI: 10.1039/C6RA22719H.].

5.
Phys Chem Chem Phys ; 19(21): 14148-14159, 2017 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-28524921

RESUMEN

The synthesis of novel and efficient catalysts for acetylene hydrogenation exhibiting high selectivity towards ethylene is important due to the presence of selective acetylene hydrogenation reaction in petrochemical processing. Since adsorption of C2 gases constitutes the primary step in catalytic hydrogenation and governs the selectivity of the catalysts, we have explored the C2-adsorption potential of reducible CeO2-based systems. The adsorption of C2-gases over CeO2-based materials was assessed using experimental in situ spectroscopic techniques and in silico theoretical studies based on density functional theory. The effect of Pd2+ substitution on adsorption was studied. The addition of Pd2+-ions was found to enhance the adsorption of the gases. Theoretical calculations provided insights into the modes of adsorption, adsorption energetics and reactant-catalyst interactions. The role of the presence of cationic substitution and anionic vacancies in strengthening the adsorption of gases was established. Pd-substituted reduced CeO2 showed activity for the adsorption of all C2 gases. On the basis of the aforementioned experimental and theoretical observations, the catalysts were tested for acetylene hydrogenation, and Pd-substituted CeO2 was found to be a good catalyst for the reaction with complete acetylene conversion observed below 100 °C.

6.
Am J Manag Care ; 22(6 Spec No.): SP198-204, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27266949

RESUMEN

OBJECTIVES: To study rates and predictors of hepatitis C virus (HCV) cure among human immunodeficiency virus (HIV)/HCV-coinfected patients, and then to evaluate the effect of attendance at clinic visits on HCV cure. METHODS: Retrospective cohort study of adult HIV/HCV-coinfected patients who initiated and completed treatment for HCV with direct-acting antivirals (DAAs) between January 1, 2014, and June 30, 2015. RESULTS: Eighty-four participants reported completing treatment. The median age was 58 years (interquartile ratio, 50-66); 88% were male and 50% were black. One-third were cirrhotic and half were HCV-treatment-experienced. The most commonly used regimen was sofosbuvir/ledipasvir (40%) followed by simeprevir/sofosbuvir (30%). Cure was achieved in 83.3%, 11.9% relapsed, and 2.3% experienced virological breakthrough. Two patients (2.3%) did not complete treatment based on pill counts and follow-up visit documentation. In multivariable analysis, cure was associated with attendance at follow-up clinic visits (odds ratio [OR], 9.0; 95% CI, 2.91-163) and with use of an integrase-based HIV regimen versus other non-integrase regimens, such as non-nucleoside analogues or protease inhibitors (OR, 6.22; 95% CI 1.81-141). Age, race, genotype, presence of cirrhosis, prior HCV treatment, HCV regimen, and pre-treatment CD4 counts were not associated with cure. CONCLUSIONS: Real-world HCV cure rates with DAAs in HCV/HIV coinfection are lower than those seen in clinical trials. Cure is associated with attendance at follow-up clinic visits and with use of an integrase-based HIV regimen. Future studies should evaluate best antiretroviral regimens, predictors of attendance at follow-up visits, impact of different monitoring protocols on medication adherence, and interventions to ensure adequate models of HIV/HCV care.


Asunto(s)
Antirretrovirales/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Hepatitis C Crónica/tratamiento farmacológico , Evaluación de Resultado en la Atención de Salud/estadística & datos numéricos , Anciano , Coinfección/tratamiento farmacológico , Quimioterapia Combinada , Femenino , Inhibidores de Integrasa VIH/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estudios Retrospectivos , Inhibidores de la Transcriptasa Inversa/uso terapéutico , Carga Viral/efectos de los fármacos , Carga Viral/estadística & datos numéricos
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