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1.
BMJ Glob Health ; 8(5)2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37230545

RESUMO

Global partnerships offer opportunities for academic departments in the health sciences to achieve mutual benefits. However, they are often challenged by inequities in power, privilege and finances between partners that have plagued the discipline of global health since its founding. In this article, a group of global health practitioners in academic medicine offer a pragmatic framework and practical examples for designing more ethical, equitable and effective collaborative global relationships between academic health science departments, building on the principles laid out by the coalition Advocacy for Global Health Partnerships in the Brocher declaration.


Assuntos
Saúde Global , Humanos
2.
Afr J Prim Health Care Fam Med ; 14(1): e1-e7, 2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-36073127

RESUMO

BACKGROUND:  The Declaration of Astana marked a revived global interest in investing in primary care as a means to achieve universal healthcare. Family medicine clinicians are uniquely trained to provide high-quality, comprehensive primary care throughout the lifespan. Yet little focus has been placed on understanding the needs of family medicine training programs. AIM:  This study aims to assess broad patterns of strengths and resource challenges faced by academic programs that train family medicine clinicians. METHODS:  An anonymous online survey was sent to family medicine faculty using World Organization of Family Doctors (WONCA) listservs. RESULTS:  Twenty-nine representatives of academic family medicine programs from around the globe answered the survey. Respondents cited funding for the program and/or individual trainees as one of either their greatest resources or greatest limitations. Frequently available resources included quality and quantity of faculty and reliable clinical training sites. Frequently noted limitations included recruitment capacity and social capital. Over half of respondents reported their program had at some point faced a disruption or gap in its ability to recruit or train, most often because of loss of government recognition. Reflecting on these patterns, respondents expressed strong interest in partnerships focusing on faculty development and research collaboration. LESSONS LEARNT:  This study provides a better understanding of the challenges family medicine training programs face and how to contribute to their sustainability and growth, particularly in terms of areas for investment, opportunities for government policy and action and areas of collaboration.


Assuntos
Medicina de Família e Comunidade , Assistência de Saúde Universal , Medicina de Família e Comunidade/educação , Humanos , Organizações , Médicos de Família , Inquéritos e Questionários
3.
J Am Chem Soc ; 141(46): 18585-18599, 2019 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-31675221

RESUMO

Hydrogen peroxide is a cosubstrate for the oxidative cleavage of saccharidic substrates by copper-containing lytic polysaccharide monooxygenases (LPMOs). The rate of reaction of LPMOs with hydrogen peroxide is high, but it is accompanied by rapid inactivation of the enzymes, presumably through protein oxidation. Herein, we use UV-vis, CD, XAS, EPR, VT/VH-MCD, and resonance Raman spectroscopies, augmented with mass spectrometry and DFT calculations, to show that the product of reaction of an AA9 LPMO with H2O2 at higher pHs is a singlet Cu(II)-tyrosyl radical species, which is inactive for the oxidation of saccharidic substrates. The Cu(II)-tyrosyl radical center entails the formation of significant Cu(II)-(●OTyr) overlap, which in turn requires that the plane of the d(x2-y2) SOMO of the Cu(II) is orientated toward the tyrosyl radical. We propose from the Marcus cross-relation that the active site tyrosine is part of a "hole-hopping" charge-transfer mechanism formed of a pathway of conserved tyrosine and tryptophan residues, which can protect the protein active site from inactivation during uncoupled turnover.

4.
J Am Chem Soc ; 141(22): 8877-8890, 2019 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-31060358

RESUMO

Copper-dependent amine oxidases produce their redox active cofactor, 2,4,5-trihydroxyphenylalanine quinone (TPQ), via the CuII-catalyzed oxygenation of an active site tyrosine. This study addresses possible mechanisms for this biogenesis process by presenting the geometric and electronic structure characterization of the CuII-bound, prebiogenesis (preprocessed) active site of the enzyme Arthrobacter globiformis amine oxidase (AGAO). CuII-loading into the preprocessed AGAO active site is slow ( kobs = 0.13 h-1), and is preceded by CuII binding in a separate kinetically favored site that is distinct from the active site. Preprocessed active site CuII is in a thermal equilibrium between two species, an entropically favored form with tyrosine protonated and unbound from the CuII site, and an enthalpically favored form with tyrosine bound deprotonated to the CuII active site. It is shown that the CuII-tyrosinate bound form is directly active in biogenesis. The electronic structure determined for the reactive form of the preprocessed CuII active site is inconsistent with a biogenesis pathway that proceeds through a CuI-tyrosyl radical intermediate, but consistent with a pathway that overcomes the spin forbidden reaction of 3O2 with the bound singlet substrate via a three-electron concerted charge-transfer mechanism.


Assuntos
Amina Oxidase (contendo Cobre)/química , Amina Oxidase (contendo Cobre)/metabolismo , Cobre/química , Di-Hidroxifenilalanina/análogos & derivados , Sítios de Ligação , Domínio Catalítico , Di-Hidroxifenilalanina/biossíntese , Modelos Moleculares
5.
Front Public Health ; 5: 174, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28791282

RESUMO

The World Health Organization estimates a global deficit of about 12.9 million skilled health professionals (midwives, nurses, and physicians) by 2035. These shortages limit the ability of countries, particularly resource-constrained countries, to deliver basic health care, to respond to emerging and more complex needs, and to teach, graduate, and retain their future health professionals-a vicious cycle that is perpetuated and has profound implications for health security. The Global Health Service Partnership (GHSP) is a unique collaboration between the Peace Corps, President's Emergency Plan for AIDS Relief, Seed and host-country institutions, which aims to strengthen the breadth and quality of medical and nursing education and care delivery in places with dire shortages of health professionals. Nurse and physician educators are seconded to host institutions to serve as visiting faculty alongside their local colleagues. They serve for 1 year with many staying longer. Educational and clinical best practices are shared, emphasis is placed on integration of theory and practice across the academic-clinical domains and the teaching and learning environment is expanded to include implementation science and dissemination of locally tailored and sustainable practice innovations. In the first 3 years (2013-2016) GHSP placed 97 nurse and physician educators in three countries (Malawi, Tanzania, and Uganda). These educators have taught 454 courses and workshops to 8,321 trainees, faculty members, and practicing health professionals across the curriculum and in myriad specialties. Mixed-methods evaluation included key stakeholder interviews with host institution faculty and students who indicate that the addition of GHSP enhanced clinical teaching (quality and breadth) resulting in improved clinical skills, confidence, and ability to connect theory to practice and critical thinking. The outputs and outcomes from four exemplars which focus on the translation of evidence to practice through implementation science are included. Findings from the first 3 years of GHSP suggest that an innovative, locally tailored and culturally appropriate multi-country academic-clinical partnership program that addresses national health priorities is feasible and generated new knowledge and best practices relevant to capacity building for nursing and medical education. This in turn has implications for improving the health of populations who suffer a disproportionate burden of global disease.

6.
J Am Chem Soc ; 139(12): 4462-4476, 2017 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-28228011

RESUMO

Spectroscopic methods and density functional theory (DFT) calculations are used to determine the geometric and electronic structure of CuZ°, an intermediate form of the Cu4S active site of nitrous oxide reductase (N2OR) that is observed in single turnover of fully reduced N2OR with N2O. Electron paramagnetic resonance (EPR), absorption, and magnetic circular dichroism (MCD) spectroscopies show that CuZ° is a 1-hole (i.e., 3CuICuII) state with spin density delocalized evenly over CuI and CuIV. Resonance Raman spectroscopy shows two Cu-S vibrations at 425 and 413 cm-1, the latter with a -3 cm-1 O18 solvent isotope shift. DFT calculations correlated to these spectral features show that CuZ° has a terminal hydroxide ligand coordinated to CuIV, stabilized by a hydrogen bond to a nearby lysine residue. CuZ° can be reduced via electron transfer from CuA using a physiologically relevant reductant. We obtain a lower limit on the rate of this intramolecular electron transfer (IET) that is >104 faster than the unobserved IET in the resting state, showing that CuZ° is the catalytically relevant oxidized form of N2OR. Terminal hydroxide coordination to CuIV in the CuZ° intermediate yields insight into the nature of N2O binding and reduction, specifying a molecular mechanism in which N2O coordinates in a µ-1,3 fashion to the fully reduced state, with hydrogen bonding from Lys397, and two electrons are transferred from the fully reduced µ4S2- bridged tetranuclear copper cluster to N2O via a single Cu atom to accomplish N-O bond cleavage.


Assuntos
Cobre/metabolismo , Marinobacter/enzimologia , Oxirredutases/metabolismo , Teoria Quântica , Biocatálise , Dicroísmo Circular , Cobre/química , Espectroscopia de Ressonância de Spin Eletrônica , Ligação de Hidrogênio , Cinética , Oxirredutases/química
7.
PRiMER ; 1: 11, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32944697

RESUMO

INTRODUCTION: The proliferation of new family medicine training programs across the globe has increased the demand for faculty development (FD) opportunities in international settings. US-based faculty may partner with international colleagues to support FD. In 2016, the Society of Teachers of Family Medicine Global Health Educators Collaborative (STFM-GHEC) began to develop a toolkit of low-cost FD resources for this purpose. To ensure that the resources appropriately target current FD needs, STFM-GHEC organized a session at the 2016 American Academy of Family Physicians (AAFP) Global Health Workshop (GHW) to collect feedback from internationally-based and US-based faculty. METHODS: The authors presented a list of faculty development topics to attendees of an AAFP GHW session entitled "Global Faculty Development Tool Kit" on September 8, 2016, in Atlanta, Georgia. Workshop participants voted up to five times each using sticky notes for the topics they felt were of greatest need. RESULTS: Forty-five participants cast 157 votes (34 from internationally-based faculty, 123 from US-based faculty). The combined group ranked curriculum development, program evaluation, and teaching methods as the most important FD needs. Both groups identified assessment strategy and time management among the least important FD needs. Other topics such as technology training and research design varied widely between the two groups in relative importance. CONCLUSIONS: This pilot demonstrates that US-based and internationally-based family medicine faculty may differ in their perceived FD needs. This exercise may be utilized by future members in global health partnerships to understand and prioritize faculty development needs.

8.
Nat Chem Biol ; 12(4): 298-303, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26928935

RESUMO

Lytic polysaccharide monooxygenases (LPMOs) are copper-containing enzymes that oxidatively break down recalcitrant polysaccharides such as cellulose and chitin. Since their discovery, LPMOs have become integral factors in the industrial utilization of biomass, especially in the sustainable generation of cellulosic bioethanol. We report here a structural determination of an LPMO-oligosaccharide complex, yielding detailed insights into the mechanism of action of these enzymes. Using a combination of structure and electron paramagnetic resonance spectroscopy, we reveal the means by which LPMOs interact with saccharide substrates. We further uncover electronic and structural features of the enzyme active site, showing how LPMOs orchestrate the reaction of oxygen with polysaccharide chains.


Assuntos
Celulose/metabolismo , Quitina/metabolismo , Oxigenases de Função Mista/metabolismo , Sequência de Aminoácidos , Aspergillus oryzae/enzimologia , Aspergillus oryzae/genética , Sítios de Ligação , Domínio Catalítico , Cobre/metabolismo , Cristalografia por Raios X , Transferência Ressonante de Energia de Fluorescência , Lentinula/enzimologia , Lentinula/genética , Oxigenases de Função Mista/química , Oxigenases de Função Mista/genética , Modelos Moleculares , Dados de Sequência Molecular , Oligossacarídeos/química , Oxirredução , Especificidade por Substrato
9.
Nat Commun ; 6: 10197, 2015 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-26680532

RESUMO

Alcohol oxidases, including carbohydrate oxidases, have a long history of research that has generated fundamental biological understanding and biotechnological applications. Despite a long history of study, the galactose 6-oxidase/glyoxal oxidase family of mononuclear copper-radical oxidases, Auxiliary Activity Family 5 (AA5), is currently represented by only very few characterized members. Here we report the recombinant production and detailed structure-function analyses of two homologues from the phytopathogenic fungi Colletotrichum graminicola and C. gloeosporioides, CgrAlcOx and CglAlcOx, respectively, to explore the wider biocatalytic potential in AA5. EPR spectroscopy and crystallographic analysis confirm a common active-site structure vis-à-vis the archetypal galactose 6-oxidase from Fusarium graminearum. Strikingly, however, CgrAlcOx and CglAlcOx are essentially incapable of oxidizing galactose and galactosides, but instead efficiently catalyse the oxidation of diverse aliphatic alcohols. The results highlight the significant potential of prospecting the evolutionary diversity of AA5 to reveal novel enzyme specificities, thereby informing both biology and applications.


Assuntos
Oxirredutases do Álcool/metabolismo , Proteínas Fúngicas/metabolismo , Galactose Oxidase/metabolismo , Oxirredutases do Álcool/química , Álcoois/metabolismo , Domínio Catalítico , Colletotrichum , Cristalização , Cristalografia por Raios X , Espectroscopia de Ressonância de Spin Eletrônica , Proteínas Fúngicas/química , Fusarium , Galactose Oxidase/química , Mutagênese Sítio-Dirigida , Filogenia , Pichia , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Espectroscopia de Prótons por Ressonância Magnética , Proteínas Recombinantes
10.
Trends Biotechnol ; 33(12): 747-761, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26472212

RESUMO

The derivation of second-generation biofuels from non-edible biomass is viewed as crucial for establishing a sustainable bio-based economy for the future. The inertness of lignocellulosic biomass makes its breakdown for conversion into fuels and other compounds a challenge. Enzyme cocktails can be utilized in the bio-refinery for lignocellulose deconstruction but until recently their costs were regarded as high. Lytic polysaccharide monooxygenases (LPMOs) offer tremendous promise for further process improvements owing to their ability to boost the activity of biomass-degrading enzyme consortia. Combining data from multiple disciplines, progress has been made in understanding the biochemistry of LPMOs. We review the academic literature in this area and highlight some of the key questions that remain.


Assuntos
Biocombustíveis , Biomassa , Biotecnologia/métodos , Oxigenases de Função Mista/metabolismo , Polissacarídeos/metabolismo , Biotecnologia/tendências , Biotransformação
11.
Chem Sci ; 6(10): 5670-5679, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26417423

RESUMO

Spectroscopic and computational methods have been used to determine the protonation state of the edge sulfur ligand in the Cu4S2 CuZ form of the active site of nitrous oxide reductase (N2OR) in its 3CuICuII (1-hole) and 2CuI2CuII (2-hole) redox states. The EPR, absorption, and MCD spectra of 1-hole CuZ indicate that the unpaired spin in this site is evenly delocalized over CuI, CuII, and CuIV. 1-hole CuZ is shown to have a µ2-thiolate edge ligand from the observation of S-H bending modes in the resonance Raman spectrum at 450 and 492 cm-1 that have significant deuterium isotope shifts (-137 cm-1) and are not perturbed up to pH 10. 2-hole CuZ is characterized with absorption and resonance Raman spectroscopies as having two Cu-S stretching vibrations that profile differently. DFT models of the 1-hole and 2-hole CuZ sites are correlated to these spectroscopic features to determine that 2-hole CuZ has a µ2-sulfide edge ligand at neutral pH. The slow two electron (+1 proton) reduction of N2O by 1-hole CuZ is discussed and the possibility of a reaction between 2-hole CuZ and O2 is considered.

13.
J Am Chem Soc ; 136(2): 614-7, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24364717

RESUMO

N2OR has been found to have two structural forms of its tetranuclear copper active site, the 4CuS Cu(Z)* form and the 4Cu2S Cu(Z) form. EPR, resonance Raman, and MCD spectroscopies have been used to determine the redox states of these sites under different reductant conditions, showing that the Cu(Z)* site accesses the 1-hole and fully reduced redox states, while the Cu(Z) site accesses the 2-hole and 1-hole redox states. Single-turnover reactions of N2OR for Cu(Z) and Cu(Z)* poised in these redox states and steady-state turnover assays with different proportions of Cu(Z) and Cu(Z)* show that only fully reduced Cu(Z)* is catalytically competent in rapid turnover with N2O.


Assuntos
Cobre/metabolismo , Marinobacter/enzimologia , Oxirredutases/metabolismo , Enxofre/metabolismo , Cobre/química , Modelos Moleculares , Oxirredutases/química , Enxofre/química
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