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1.
Conserv Biol ; 35(4): 1086-1097, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33244774

RESUMO

Decades of research and policy interventions on biodiversity have insufficiently addressed the dual issues of biodiversity degradation and social justice. New approaches are therefore needed. We devised a research and action agenda that calls for a collective task of revisiting biodiversity toward the goal of sustaining diverse and just futures for life on Earth. Revisiting biodiversity involves critically reflecting on past and present research, policy, and practice concerning biodiversity to inspire creative thinking about the future. The agenda was developed through a 2-year dialogue process that involved close to 300 experts from diverse disciplines and locations. This process was informed by social science insights that show biodiversity research and action is underpinned by choices about how problems are conceptualized. Recognizing knowledge, action, and ethics as inseparable, we synthesized a set of principles that help navigate the task of revisiting biodiversity. The agenda articulates 4 thematic areas for future research. First, researchers need to revisit biodiversity narratives by challenging conceptualizations that exclude diversity and entrench the separation of humans, cultures, economies, and societies from nature. Second, researchers should focus on the relationships between the Anthropocene, biodiversity, and culture by considering humanity and biodiversity as tied together in specific contexts. Third, researchers should focus on nature and economies by better accounting for the interacting structures of economic and financial systems as core drivers of biodiversity loss. Finally, researchers should enable transformative biodiversity research and action by reconfiguring relationships between human and nonhuman communities in and through science, policy, and practice. Revisiting biodiversity necessitates a renewed focus on dialogue among biodiversity communities and beyond that critically reflects on the past to channel research and action toward fostering just and diverse futures for human and nonhuman life on Earth.


Una Agenda para la Investigación y la Acción hacia un Futuro Diverso y Justo para la Vida sobre la Tierra Resumen Las décadas de investigación e intervenciones políticas sobre la biodiversidad han tratado significativamente los temas de la degradación de la biodiversidad y la justicia social. Debido a esto, se requieren nuevas estrategias. Diseñamos una agenda de investigación y acción que llama a la labor colectiva de revisar la biodiversidad hacia el objetivo de sustentar un futuro diverso y justo para la vida sobre la Tierra. Cuando se revisa la biodiversidad, se requiere de una reflexión crítica sobre las investigaciones, políticas y prácticas presentes y pasadas sobre la biodiversidad para inspirar un pensamiento creativo acerca del futuro. Desarrollamos la agenda por medio de un proceso de diálogo de dos años que involucró a casi 300 expertos de diversas disciplinas y localidades. Este proceso estuvo orientado por el conocimiento de las ciencias sociales que muestra cómo la investigación y la acción para la biodiversidad están sostenidas por las opciones de cómo están conceptualizados los problemas. Reconocimos al conocimiento, la acción y la ética como inseparables y sintetizamos un conjunto de principios que ayuda a navegar la labor de revisar la biodiversidad. La agenda articula cuatro áreas temáticas para la investigación en el futuro. Primero, los investigadores necesitan revisar las narrativas de la biodiversidad mediante el cuestionamiento de las conceptualizaciones que excluyen a la diversidad y consolidan la separación entre humanos, culturas, economías y sociedades y la naturaleza. Segundo, los investigadores deberían enfocarse en las relaciones entre el antropoceno, la biodiversidad y la cultura al considerar a la humanidad y la biodiversidad como interconectadas en contextos específicos. Tercero, los investigadores deberían enfocarse en la naturaleza y las economías al tener en mejor cuenta la interacción de las estructuras de los sistemas económico y financiero como conductores nucleares de la pérdida de la biodiversidad. Finalmente, los investigadores deberían permitir la investigación y acción transformadoras de la biodiversidad al reconfigurar las relaciones entre las comunidades humanas y no humanas dentro y a través de la ciencia, la política y la práctica. La revisión de la biodiversidad necesita de un enfoque renovado sobre el diálogo entre las comunidades de la biodiversidad y más allá, que reflexione críticamente sobre el pasado para canalizar a la investigación y acción hacia el fomento del futuro justo y diverso para la vida humana y no humana sobre la Tierra.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Previsões , Humanos , Justiça Social
2.
BJOG ; 124(5): 815-824, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27862882

RESUMO

OBJECTIVE: To examine contraceptive choices among women seeking termination of pregnancy (TOP) and the provision of the chosen methods. DESIGN: Population-based study. SETTING: British Pregnancy Advisory Service (BPAS) clinics in England and Wales. POPULATION: Between 1 January 2011 and 31 December 2014, 211 215 women had a TOP at BPAS, were offered contraceptive counselling, and were eligible to obtain contraception at no cost. METHODS: We examined electronic records from BPAS and assessed the proportions of women who accepted contraceptive counselling and chose a contraceptive method, as well as the distributions of methods chosen, analysed by provider and by TOP type. We calculated the proportions receiving their chosen method and the methods chosen by women using no method at conception. We used logistic regression to examine the factors associated with choice of an intrauterine contraceptive (IUC) or implant. MAIN OUTCOME MEASURES: Post-TOP contraceptive method choice. Receipt of chosen method post-TOP. RESULTS: Eighty-five per cent of women accepted contraceptive counselling and 51% chose to obtain a method from BPAS rather than from a GP or contraception and sexual health clinic post-TOP. [correction added on 25 November 2016 after first online publication: 51% has been inserted in the preceding sentence.] Among those who wanted to receive contraception from BPAS, 51% chose an IUC or implant and 19% chose oral contraceptives. Ninety-one per cent of women who obtained contraception from BPAS received their chosen method. Women were more likely to choose an IUC or implant if they obtained contraception from BPAS, had a surgical TOP, were parous, young, white, or had one or more previous TOPs. CONCLUSIONS: The standards set for patient-centred TOP care should emphasise the need for a full range of contraceptive options to be offered and provided post-TOP. TWEETABLE ABSTRACT: Uptake targets for long-acting reversible methods do not reflect women's post-TOP contraceptive preferences.


Assuntos
Aborto Induzido/estatística & dados numéricos , Comportamento Contraceptivo/estatística & dados numéricos , Anticoncepção/estatística & dados numéricos , Adolescente , Adulto , Criança , Comportamento de Escolha , Aconselhamento , Inglaterra , Serviços de Planejamento Familiar/estatística & dados numéricos , Feminino , Humanos , Pessoa de Meia-Idade , Gravidez , País de Gales , Adulto Jovem
3.
J Mol Biol ; 399(1): 71-93, 2010 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-20361979

RESUMO

Mammalian pyruvate dehydrogenase complex (PDC) is a key multi-enzyme assembly that is responsible for glucose homeostasis maintenance and conversion of pyruvate into acetyl-CoA. It comprises a central pentagonal dodecahedral core consisting of two subunit types (E2 and E3BP) to which peripheral enzymes (E1 and E3) bind tightly but non-covalently. Currently, there are two conflicting models of PDC (E2+E3BP) core organisation: the 'addition' model (60+12) and the 'substitution' model (48+12). Here we present the first ever low-resolution structures of human recombinant full-length PDC core (rE2/E3BP), truncated PDC core (tE2/E3BP) and native bovine heart PDC core (bE2/E3BP) obtained by small-angle X-ray scattering and small-angle neutron scattering. These structures, corroborated by negative-stain and cryo electron microscopy data, clearly reveal open pentagonal core faces, favouring the 'substitution' model of core organisation. The native and recombinant core structures are all similar to the truncated bacterial E2 core crystal structure obtained previously. Cryo-electron microscopy reconstructions of rE2/E3BP and rE2/E3BP:E3 directly confirm that the core has open pentagonal faces, agree with scattering-derived models and show density extending outwards from their surfaces, which is much more structurally ordered in the presence of E3. Additionally, analytical ultracentrifugation characterisation of rE2/E3BP, rE2 (full-length recombinant E2-only) and tE2/E3BP supports the substitution model. Superimposition of the small-angle neutron scattering tE2/E3BP and truncated bacterial E2 crystal structures demonstrates conservation of the overall pentagonal dodecahedral morphology, despite evolutionary diversity. In addition, unfolding studies using circular dichroism and tryptophan fluorescence spectroscopy show that the rE2/E3BP is less stable than its rE2 counterpart, indicative of a role for E3BP in core destabilisation. The architectural complexity and lower stability of the E2/E3BP core may be of benefit to mammals, where sophisticated fine-tuning is required for cores with optimal catalytic and regulatory efficiencies.


Assuntos
Complexo Piruvato Desidrogenase/química , Sequência de Aminoácidos , Sítios de Ligação , Microscopia Crioeletrônica , Humanos , Dados de Sequência Molecular , Conformação Proteica , Subunidades Proteicas/química , Subunidades Proteicas/metabolismo , Complexo Piruvato Desidrogenase/metabolismo , Alinhamento de Sequência
4.
J Org Chem ; 66(19): 6375-80, 2001 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-11559189

RESUMO

A synthetic route has been developed which has allowed us to prepare novel alpha-aminoboronic acids as inhibitors of serine proteases. These compounds were prepared to study the roles of proteases in biological systems. This methodology affords alpha-aminoboronic acids with the general formula R'-NHCH(R)BO(2)-pinanediol, where R = -CH(2)CHF(2), -CH(2)CO(2)tBu, and -(CH(2))(2)CO(2)Me and R' = either H or C(O)R". The latter two compounds are the boronic acid analogues of the natural amino acids aspartic acid and glutamic acid with the side chain carboxylate protected as a tert-butyl or a methyl ester, respectively. Following acylation of the amino group, the side chain tert-butyl ester of boroaspartic acid was removed by treatment with TFA. Boroglutamic acid was obtained as the free boronic acid by hydrolysis with HCl. Prior syntheses of alpha-aminoboronic acids involve the initial addition of an organometallic reagent to a trialkyl borate ester. These conditions do not allow the preparation of compounds with functionalities that are not stable to the strongly basic reaction conditions. The methodology described here allows the preparation of alpha-aminoboronic acids by introducing side chains as electrophiles. This is particularly advantageous for side chains which are prone to elimination or unwanted enolate formation. Specifically, BrCH(2)CHF(2), BrCH(2)COO(t)Bu, and CH(2)=CHCOOMe were allowed to react with the stabilized anion of (phenylthio)methane boronate, PhSCH(2)BO(2)C(6)H(12), to give the substituted boronate. The substituted (phenylthio)methane boronate was converted to the corresponding sulfonium ion by treatment with methyl iodide and subsequently displaced with iodide. The alpha-iodo derivative was converted to the amine by conventional methods.


Assuntos
Aminoácidos/síntese química , Ácidos Borônicos/síntese química , Inibidores de Serina Proteinase/síntese química , Aminoácidos/farmacologia , Ácidos Borônicos/farmacologia , Serina Endopeptidases/efeitos dos fármacos , Serina Endopeptidases/metabolismo , Inibidores de Serina Proteinase/farmacologia
5.
Neonatal Netw ; 17(7): 23-34, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9850193

RESUMO

A primary goal of health care today is finding alternative ways to provide high-quality, cost-effective care. A model of care that addresses these issues is nursing case management. This article describes the development and implementation of nursing case management in a Level III regional center with the primary goal of enhancing coordination for discharge planning. The model involves development of clinical pathways and utilization of nurse practitioners as case managers. Decreased length of stay, charge per case, and readmission rates are demonstrated following implementation of this program.


Assuntos
Administração de Caso/organização & administração , Cuidado do Lactente/organização & administração , Unidades de Terapia Intensiva Neonatal/organização & administração , Alta do Paciente , Procedimentos Clínicos/organização & administração , Humanos , Lactente , Recém-Nascido , North Carolina , Enfermeiros Clínicos/organização & administração , Profissionais de Enfermagem/organização & administração , Equipe de Assistência ao Paciente
6.
Biophys Chem ; 70(2): 161-72, 1998 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-9540207

RESUMO

A high-angle X-ray fibre diffraction study of a tubercidin analogue of the poly[d(A-T)].poly[d(A-T)] DNA double helix has been carried out using station 7.2 at the Daresbury Laboratory synchrotron radiation source. The polymer has been studied for a wide range of salt strengths and hydration conditions and exhibits conformational polymorphism that is quite distinct from that observed for the unmodified polymer. The replacement of deoxyadenosine by deoxytubercidin in the polynucleotide causes only slight alterations to the structure of A-DNA, but significantly alters the structure of the B conformation. Additionally, the modified polymer does not, in any conditions yet identified, adopt the D conformation. In conditions which would normally favour the D conformation of poly[d(A-T)].poly[d(A-T)], the modified polymer adopts an unusual conformation which is designated here as the K conformation. These observations are important for an understanding of major groove interactions involved in the stabilisation of particular DNA conformations and also more generally for an insight into the pharmacological activity of tubercidin which following its incorporation into nucleic acids may cause stereochemical distortions of the DNA double helix.


Assuntos
DNA/química , Poli dA-dT/química , Tubercidina/química , DNA/metabolismo , Conformação Molecular , Estrutura Molecular , Conformação de Ácido Nucleico , Poli dA-dT/metabolismo , Polímeros/química , Tubercidina/metabolismo , Difração de Raios X/instrumentação
7.
Biophys Chem ; 69(1): 85-96, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9440211

RESUMO

A high-angle neutron fibre diffraction study of the hydration of A-DNA has been performed using the single-crystal diffractometer D19 at the Institut Laue-Langevin (Grenoble, France). The sample was prepared using deuterated DNA extracted from E. Coli cells cultured on deuterated nutrients. In common with our previous neutron fibre diffraction studies of DNA, this work exploits the ability to isotopically replace H2O around the DNA by D2O. However this study benefitted additionally from the fact that the hydrogen atoms which are covalently bonded to carbon atoms in the DNA sugars and bases were replaced by deuterium so that incoherent scattering and absorption effects were minimised. Successive cycles of Fourier synthesis and Fourier difference synthesis allowed water peaks to be identified and their positional and occupancy parameters to be refined against the observed diffraction data. The results confirm the main hydration features noted in our earlier studies with a clear network of water running along the inside edge of the major groove linking successive OI phosphate oxygen atoms. The central core of water running along the axis of the double helix is very much clearer in this work. Additionally this study shows chains of ordered water lying in the centre of the major groove.


Assuntos
DNA Bacteriano/química , Deutério , Conformação de Ácido Nucleico , Cristalografia/métodos , Escherichia coli/genética , Estrutura Molecular , Nêutrons , Água/química
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