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1.
Curr Pharm Teach Learn ; 16(9): 102120, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38875752

RESUMO

The overwhelming majority of states require pharmacists to pass the Multistate Pharmacy Jurisprudence Exam (MPJE) prior to licensure, and student performance in the pharmacy law course is the biggest predictor of success on the MPJE. However, wide variation exists regarding the structure and delivery of the pharmacy law course. Evidence-based learning strategies are well described in the literature, including: (1) practice testing, (2) distributed practice, (3) interleaved practice, (4) self-explanation, and (5) interrogative elaboration, and an opportunity may exist to implement them into the pharmacy law course. We translated these five evidence-based learning principles into practice for pharmacy law educators with specific examples. Faculty directing the pharmacy law course may consider implementing evidence-based teaching strategies into their pharmacy law course to further support student success.

2.
Angew Chem Int Ed Engl ; : e202403493, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38662909

RESUMO

Cyclopropane fatty acid synthases (CFAS) are a class of S-adenosylmethionine (SAM) dependent methyltransferase enzymes able to catalyse the cyclopropanation of unsaturated phospholipids. Since CFAS enzymes employ SAM as a methylene source to cyclopropanate alkene substrates, they have the potential to be mild and more sustainable biocatalysts for cyclopropanation transformations than current carbene-based approaches. This work describes the characterisation of E. coli CFAS (ecCFAS) and its exploitation in the stereoselective biocatalytic synthesis of cyclopropyl lipids. ecCFAS was found to convert phosphatidylglycerol (PG) to methyl dihydrosterculate 1 with up to 58 % conversion and 73 % ee and the absolute configuration (9S,10R) was established. Substrate tolerance of ecCFAS was found to be correlated with the electronic properties of phospholipid headgroups and for the first time ecCFAS was found to catalyse cyclopropanation of both phospholipid chains to form dicyclopropanated products. In addition, mutagenesis and in silico experiments were carried out to identify the enzyme residues with key roles in catalysis and to provide structural insights into the lipid substrate preference of ecCFAS. Finally, the biocatalytic synthesis of methyl dihydrosterculate 1 and its deuterated analogue was also accomplished combining recombinant ecCFAS with the SAM regenerating AtHMT enzyme in the presence of CH3I and CD3I respectively.

3.
ACS Catal ; 14(5): 2985-2991, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38449536

RESUMO

The unmatched chemo-, regio-, and stereoselectivity of enzymes renders them powerful catalysts in the synthesis of chiral active pharmaceutical ingredients (APIs). Inspired by the discovery route toward the LPA1-antagonist BMS-986278, access to the API building block (1S,3R)-3-hydroxycyclohexanecarbonitrile was envisaged using an ene reductase (ER) and alcohol dehydrogenase (ADH) to set both stereocenters. Starting from the commercially available cyclohexene-1-nitrile, a C-H oxyfunctionalization step was required to introduce the ketone functional group, yet several chemical allylic oxidation strategies proved unsuccessful. Enzymatic strategies for allylic oxidation are underdeveloped, with few examples on selected substrates with cytochrome P450s and unspecific peroxygenases (UPOs). In this case, UPOs were found to catalyze the desired allylic oxidation with high chemo- and regioselectivity, at substrate loadings of up to 200 mM, without the addition of organic cosolvents, thus enabling the subsequent ER and ADH steps in a three-step one-pot cascade. UPOs even displayed unreported enantioselective oxyfunctionalization and overoxidation of the substituted cyclohexene. After screening of enzyme panels, the final product was obtained at titers of 85% with 97% ee and 99% de, with a substrate loading of 50 mM, the ER being the limiting step. This synthetic approach provides the first example of a three-step, one-pot UPO-ER-ADH cascade and highlights the potential for UPOs to catalyze diverse enantioselective allylic hydroxylations and oxidations that are otherwise difficult to achieve.

4.
Acad Pediatr ; 24(4): 700-704, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38211768

RESUMO

OBJECTIVE: In 2006 the Association of American Medical Colleges recommended standardization of documentation of the contributions of medical educators and guidelines for their academic promotion. The authors characterized current United States (US) medical school promotion guidelines for medical educators. METHODS: Authors collected publicly available data from medical school promotion websites from March through July 2022 after determining categories by traditional-set domains as well as peer-reviewed standards. Extracted data were analyzed using descriptive and inferential statistics, and frequencies were calculated for nominal and categorical data. RESULTS: Of 155 medical schools identified, promotion criteria were publicly available for 143 (92%) schools. Ninety-one (64%) schools identified a distinct educator track. Of those with a defined educator track, 44 (48%) schools consider workshops or other media when evaluating candidates for promotion, and only 52 (57%) of schools with a specified educational track require additional documentation of teaching or education as part of their promotion process. Notably, 34 (37%) of the 91 schools with an educator track specifically require an Educational Portfolio, compared to 27 (52%) of the 52 schools that do not have a specific educator track for promotion. CONCLUSION: This study describes the current lack of clarity and consistency of the promotion criteria for medical educators and indicates that the guidelines proposed by the Association of American Medical Colleges over 15 years ago have not been widely adopted. These data amplify previous calls for a more objective set of criteria for evaluating and recognizing the contributions of medical educators.


Assuntos
Docentes de Medicina , Faculdades de Medicina , Humanos , Estados Unidos , Guias como Assunto , Mobilidade Ocupacional , Educação Médica
5.
Acad Pediatr ; 24(2): 359-368, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37907127

RESUMO

OBJECTIVE: To perform a qualitative content analysis of learning and assessment strategies that pediatric subinterns describe in Individualized Learning Plans (ILPs) and to explore barriers and facilitators to their learning. METHODS: We analyzed ILPs from medical students enrolled in pediatric subinternships at 10 US medical schools that utilized a standardized curriculum and were recruited to reflect diversity in geographic location, funding, and enrollment. Students used an ILP to record 3 or more selected learning objectives, rationale for selection, and reflection on learning and assessment strategies. Investigators used the constant comparative method to perform a content analysis of the ILPs, grouping codes into themes, and verifying relationships between codes within themes. RESULTS: Two hundred and four ILPs that included student reflections on 850 learning objectives were analyzed. Content was analyzed in 5 categories: rationale for selecting objectives, learning strategies, assessment strategies, challenges to learning, and facilitators of learning. Students showed strong commitment to individualized, self-directed learning, developed a wide range of creative learning strategies, and relied heavily on self-reflection to assess their progress. The learning environment both helped and hindered students' ability to make and assess progress on their selected learning objectives. CONCLUSIONS: Through ILP-guided reflection and a formal curriculum, students can choose well-justified learning objectives and demonstrate resourcefulness and independence in developing self-directed learning and assessment strategies. The strategies that students identified in this study provide a menu of learning and assessment options for subinterns. Identified challenges and facilitators of learning provide guidance for educators who seek to enhance the clinical learning environment.


Assuntos
Educação de Graduação em Medicina , Estudantes de Medicina , Humanos , Criança , Aprendizagem , Currículo , Educação de Graduação em Medicina/métodos , Competência Clínica
6.
Catal Sci Technol ; 13(19): 5530-5535, 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-38013840

RESUMO

Biocatalytic asymmetric reduction of alkenes in organic solvent is attractive for enantiopurity and product isolation, yet remains under developed. Herein we demonstrate the robustness of an ene reductase immobilised on Celite for the reduction of activated alkenes in micro-aqueous organic solvent. Full conversion was obtained in methyl t-butyl ether, avoiding hydrolysis and racemisation of products. The immobilised ene reductase showed reusability and a scale-up demonstrated its applicability.

7.
JACS Au ; 3(6): 1642-1649, 2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37388678

RESUMO

Chiral N-heterocycles are a common motif in many active pharmaceutical ingredients; however, their synthesis often relies on the use of heavy metals. In recent years, several biocatalytic approaches have emerged to reach enantiopurity. Here, we describe the asymmetric synthesis of 2-substituted pyrrolidines and piperidines, starting from commercially available ω-chloroketones by using transaminases, which has not yet been comprehensively studied. Analytical yields of up to 90% and enantiomeric excesses of up to >99.5% for each enantiomer were achieved, which has not previously been shown for bulky substituents. This biocatalytic approach was applied to synthesize (R)-2-(p-chlorophenyl)pyrrolidine on a 300 mg scale, affording 84% isolated yield, with >99.5% ee.

8.
Angew Chem Int Ed Engl ; 62(24): e202302844, 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37022339

RESUMO

A peroxygenase-catalysed hydroxylation of organosilanes is reported. The recombinant peroxygenase from Agrocybe aegerita (AaeUPO) enabled efficient conversion of a broad range of silane starting materials in attractive productivities (up to 300 mM h-1 ), catalyst performance (up to 84 s-1 and more than 120 000 catalytic turnovers). Molecular modelling of the enzyme-substrate interaction puts a basis for the mechanistic understanding of AaeUPO selectivity.

9.
Acad Radiol ; 30(8): 1756-1761, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36528427

RESUMO

RATIONALE AND OBJECTIVES: While the ACGME requires Resident as Teacher (RAT) training, curricula in radiology remain limited. Our study was performed to examine radiology residents (RR) and teaching faculty (TF) perceptions about RAT training. MATERIALS AND METHODS: In 2021, anonymous online surveys were administered to all RR (53-item) and to all TF (24-item) of a radiology residency program. Content domains included attitudes about RAT training and learning topics. RESULTS: Response rates were 97% (38/39) for RR and 54% (58/107) for TF. Most RR desired training to become better educators to medical students (MS) (81%) and other residents (83%). Seventy-seven percent of RR reported the importance regarding how to give feedback to other learners, while 94% desired formal training on delivering case presentations. While 94% of RR reported that resident feedback was valuable, only 6% reported always giving feedback to MS. Seventy-two percent of RR did not apply at least some best-practices in their reading room teaching. Fifty-nine percent of RR wanted TF to observe their own teaching skills and provide feedback although 70% reported rarely or never receiving TF feedback. Ninety-three percent of TF reported RR should receive RAT training, while 88% reported that feedback of RR to MS was important. CONCLUSION: RR and TF strongly endorsed the need for RAT training. RR anticipate teaching to be an important part of their careers. We identified learning topics and possible gaps regarding how TF are meeting RR needs, which could inform the development of RAT curricula.


Assuntos
Internato e Residência , Radiologia , Capacitação de Professores , Humanos , Aprendizagem , Currículo , Docentes , Ensino
10.
Chem Commun (Camb) ; 58(75): 10540-10543, 2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36047350

RESUMO

We demonstrate a recycling system for synthetic nicotinamide cofactor analogues using a soluble hydrogenase with turnover number of >1000 for reduction of the cofactor analogues by H2. Coupling this system to an ene reductase, we show quantitative conversion of N-ethylmaleimide to N-ethylsuccinimide. The biocatalyst system retained >50% activity after 7 h.


Assuntos
Hidrogenase , Etilmaleimida , Hidrogênio , Hidrogenase/metabolismo , NAD/metabolismo , Niacinamida , Oxirredução , Oxirredutases/metabolismo , Succinimidas
11.
Nat Commun ; 13(1): 5021, 2022 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-36028482

RESUMO

Noncanonical redox cofactors are attractive low-cost alternatives to nicotinamide adenine dinucleotide (phosphate) (NAD(P)+) in biotransformation. However, engineering enzymes to utilize them is challenging. Here, we present a high-throughput directed evolution platform which couples cell growth to the in vivo cycling of a noncanonical cofactor, nicotinamide mononucleotide (NMN+). We achieve this by engineering the life-essential glutathione reductase in Escherichia coli to exclusively rely on the reduced NMN+ (NMNH). Using this system, we develop a phosphite dehydrogenase (PTDH) to cycle NMN+ with ~147-fold improved catalytic efficiency, which translates to an industrially viable total turnover number of ~45,000 in cell-free biotransformation without requiring high cofactor concentrations. Moreover, the PTDH variants also exhibit improved activity with another structurally deviant noncanonical cofactor, 1-benzylnicotinamide (BNA+), showcasing their broad applications. Structural modeling prediction reveals a general design principle where the mutations and the smaller, noncanonical cofactors together mimic the steric interactions of the larger, natural cofactors NAD(P)+.


Assuntos
NADH NADPH Oxirredutases , NAD , Escherichia coli , NADP , Oxirredução
12.
Chembiochem ; 23(15): e202200293, 2022 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-35648642

RESUMO

Temperature is a crucial parameter for biological and chemical processes. Its effect on enzymatically catalysed reactions has been known for decades, and stereo- and enantiopreference are often temperature-dependent. For the first time, we present the temperature effect on the Baeyer-Villiger oxidation of rac-bicyclo[3.2.0]hept-2-en-6-one by the type II Bayer-Villiger monooxygenase, 2,5-DKCMO. In the absence of a reductase and driven by the hydride-donation of a synthetic nicotinamide analogue, the clear trend for a decreasing enantioselectivity at higher temperatures was observed. "Traditional" approaches such as the determination of the enantiomeric ratio (E) appeared unsuitable due to the complexity of the system. To quantify the trend, we chose to use the 'Shape Language Modelling' (SLM), a tool that allows the reaction to be described at all points in a shape prescriptive manner. Thus, without knowing the equation of the reaction, the substrate ee can be estimated that at any conversion.


Assuntos
Escherichia coli , Oxigenases de Função Mista , Escherichia coli/enzimologia , Oxigenases de Função Mista/metabolismo , Oxirredução , Temperatura
13.
Med Sci Educ ; 32(2): 287-290, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35194522

RESUMO

Medical education conferences offer practical workshops to facilitate physicians' lifelong learning. Little is known about integration of workshop material after conferences. We sought to evaluate the application of workshop content focused on scholarly publication preparation. We developed an email survey to examine participants' progress preparing a publication in 2019, administered 4, 9, and 15 months post-conference. The survey included scaled items and open-ended questions. Thirty-three participants attended the workshop. Participants continued to develop their projects, but noted time, adequate evaluations, and no writing partners as barriers. Following up with workshop participants offers insights into effective application of workshop content.

14.
ACS Catal ; 12(2): 1111-1116, 2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35096467

RESUMO

Biocatalytic pathways for the synthesis of (-)-menthol, the most sold flavor worldwide, are highly sought-after. To access the key intermediate (R)-citronellal used in current major industrial production routes, we established a one-pot bienzymatic cascade from inexpensive geraniol, overcoming the problematic biocatalytic reduction of the mixture of (E/Z)-isomers in citral by harnessing a copper radical oxidase (CgrAlcOx) and an old yellow enzyme (OYE). The cascade using OYE2 delivered 95.1% conversion to (R)-citronellal with 95.9% ee, a 62 mg scale-up affording high yield and similar optical purity. An alternative OYE, GluER, gave (S)-citronellal from geraniol with 95.3% conversion and 99.2% ee.

15.
Chembiochem ; 23(6): e202200017, 2022 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-35023279

RESUMO

In this study, we developed a new bienzymatic reaction to produce enantioenriched phenylethanols. In a first step, the recombinant, unspecific peroxygenase from Agrocybe aegerita (rAaeUPO) was used to oxidise ethylbenzene and its derivatives to the corresponding ketones (prochiral intermediates) followed by enantioselective reduction into the desired (R)- or (S)-phenylethanols using the (R)-selective alcohol dehydrogenase (ADH) from Lactobacillus kefir (LkADH) or the (S)-selective ADH from Rhodococcus ruber (ADH-A). In a one-pot two-step cascade, 11 ethylbenzene derivatives were converted into the corresponding chiral alcohols at acceptable yields and often excellent enantioselectivity.


Assuntos
Álcool Desidrogenase , Álcool Feniletílico , Álcool Desidrogenase/metabolismo , Derivados de Benzeno , Oxigenases de Função Mista , Oxirredução , Estereoisomerismo
16.
Intern Emerg Med ; 17(1): 65-69, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34047911

RESUMO

The relation between long-haul flights (LHF) and venous thromboembolic disease is well established. Nonetheless, the incidence of pulmonary embolisms after these flights is probably underestimated because of the difficulties in case ascertainment. Reunion Island appears to present the ideal geographic conditions for accurately assessing this incidence. We aimed to assess the incidence of pulmonary embolisms in people who had recently taken a LHF to Reunion Island. We conducted a retrospective multi-center descriptive study and included all cases of pulmonary embolisms diagnosed between January 1, 2015, and January 30, 2017 (according to the hospitals' discharge summary database) in the island's four public hospitals within 30 days after taking an LHF to Reunion. We took different delays of diagnosis to calculate the incidence. We have considered the time to diagnosis at 1 month as significant according to the time applied in the Geneva score for risk factors. The study included 45 patients landing on Reunion over a 2-year period. The total number of passengers arriving by LHF during this period was 1,223,001. The incidence of pulmonary embolism after an LHF was thus calculated at 36.8 per million travelers at 1 month. The incidence for PE diagnosed, after 15 days was 29.4 per million travelers, and after 7 days, it was 21.9 per million travelers. The male/female ratio was 0.67. The mean interval between the flight and symptom onset was 7 days. In our population, the incidence of pulmonary embolisms after LHFs in our study is clearly higher than that reported in the literature (36.8 vs 4.8). Our exhaustive data collection probably explains this difference. A case-control study appears necessary to analyze the risk factors for pulmonary embolism after a LHF.


Assuntos
Embolia Pulmonar , Trombose Venosa , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Embolia Pulmonar/complicações , Embolia Pulmonar/etiologia , Estudos Retrospectivos , Fatores de Risco , Viagem , Trombose Venosa/etiologia
17.
Chem Soc Rev ; 51(2): 594-627, 2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-34929722

RESUMO

Biocatalysis has an enormous impact on chemical synthesis. The waves in which biocatalysis has developed, and in doing so changed our perception of what organic chemistry is, were reviewed 20 and 10 years ago. Here we review the consequences of these waves of development. Nowadays, hydrolases are widely used on an industrial scale for the benign synthesis of commodity and bulk chemicals and are fully developed. In addition, further enzyme classes are gaining ever increasing interest. Particularly, enzymes catalysing selective C-C-bond formation reactions and enzymes catalysing selective oxidation and reduction reactions are solving long-standing synthetic challenges in organic chemistry. Combined efforts from molecular biology, systems biology, organic chemistry and chemical engineering will establish a whole new toolbox for chemistry. Recent developments are critically reviewed.


Assuntos
Química Orgânica , Enzimas , Biocatálise , Catálise , Enzimas/metabolismo , Oxirredução
18.
ACS Catal ; 11(18): 11561-11569, 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34557329

RESUMO

Nicotinamide adenine dinucleotide (NAD) and its 2'-phosphorylated form NADP are crucial cofactors for a large array of biocatalytically important redox enzymes. Their high cost and relatively poor stability, however, make them less attractive electron mediators for industrial processes. Nicotinamide cofactor biomimetics (NCBs) are easily synthesized, are inexpensive, and are also generally more stable than their natural counterparts. A bottleneck for the application of these artificial hydride carriers is the lack of efficient cofactor recycling methods. Therefore, we engineered the thermostable F420:NADPH oxidoreductase from Thermobifida fusca (Tfu-FNO), by structure-inspired site-directed mutagenesis, to accommodate the unnatural N1 substituents of eight NCBs. The extraordinarily low redox potential of the natural cofactor F420H2 was then exploited to reduce these NCBs. Wild-type enzyme had detectable activity toward all selected NCBs, with K m values in the millimolar range and k cat values ranging from 0.09 to 1.4 min-1. Saturation mutagenesis at positions Gly-29 and Pro-89 resulted in mutants with up to 139 times higher catalytic efficiencies. Mutant G29W showed a k cat value of 4.2 s-1 toward 1-benzyl-3-acetylpyridine (BAP+), which is similar to the k cat value for the natural substrate NADP+. The best Tfu-FNO variants for a specific NCB were then used for the recycling of catalytic amounts of these nicotinamides in conversion experiments with the thermostable ene-reductase from Thermus scotoductus (TsOYE). We were able to fully convert 10 mM ketoisophorone with BAP+ within 16 h, using F420 or its artificial biomimetic FOP (FO-2'-phosphate) as an efficient electron mediator and glucose-6-phosphate as an electron donor. The generated toolbox of thermostable and NCB-dependent Tfu-FNO variants offers powerful cofactor regeneration biocatalysts for the reduction of several artificial nicotinamide biomimetics at both ambient and high temperatures. In fact, to our knowledge, this enzymatic method seems to be the best-performing NCB-recycling system for BNAH and BAPH thus far.

19.
Catal Sci Technol ; 11(15): 5077-5085, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34381590

RESUMO

Enantioenriched azido alcohols are precursors for valuable chiral aziridines and 1,2-amino alcohols, however their chiral substituted analogues are difficult to access. We established a cascade for the asymmetric azidohydroxylation of styrene derivatives leading to chiral substituted 1,2-azido alcohols via enzymatic asymmetric epoxidation, followed by regioselective azidolysis, affording the azido alcohols with up to two contiguous stereogenic centers. A newly isolated two-component flavoprotein styrene monooxygenase StyA proved to be highly selective for epoxidation with a nicotinamide coenzyme biomimetic as a practical reductant. Coupled with azide as a nucleophile for regioselective ring opening, this chemo-enzymatic cascade produced highly enantioenriched aromatic α-azido alcohols with up to >99% conversion. A bi-enzymatic counterpart with halohydrin dehalogenase-catalyzed azidolysis afforded the alternative ß-azido alcohol isomers with up to 94% diastereomeric excess. We anticipate our biocatalytic cascade to be a starting point for more practical production of these chiral compounds with two-component flavoprotein monooxygenases.

20.
Chembiochem ; 22(14): 2420-2423, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34002919

RESUMO

The fatty acid photodecarboxylase from Chlorella variabilis NC64 A (CvFAP) catalyses the light-dependent decarboxylation of fatty acids. Photoinactivation of CvFAP still represents one of the major limitations of this interesting enzyme en route to practical application. In this study we demonstrate that the photostability of CvFAP can easily be improved by the administration of medium-chain length carboxylic acids such as caprylic acid indicating that the best way of maintaining CvFAP stability is 'to keep the enzyme busy'.


Assuntos
Chlorella , Ácidos Graxos
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