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1.
J Frailty Aging ; 13(2): 189-192, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38616377

RESUMO

BACKGROUND: Knowledge of frailty is essential for meeting the Accreditation Council for Graduate Medical Education core competencies for US trainees. The UK General Medical Council requires that frailty be included in undergraduate and graduate medical education curricula. Trainees are expected to appropriately modify care plans and help make patient-centered decisions, while incorporating diagnostic uncertainty, such as frailty, in older adults. Little is known about current needs for frailty instruction in graduate medical education in the US and beyond. OBJECTIVE: We sought to capture faculty perceptions on how frailty should be defined and identified, and what aspects and level of detail should be taught to residents. DESIGN: The authors developed a 4-item short response questionnaire, and faculty had the option to respond via electronic survey or via semi-structured interviews. SETTING AND SUBJECTS: Respondents included 24 fellowship-trained geriatricians based at 6 different academic medical centers in a single urban metropolitan area. METHODS: An invitation to participate in either an electronic survey or semi-structured virtual interview was e-mailed to 30 geriatricians affiliated with an academic multi-campus Geriatric Medicine fellowship. Responses were transcribed and coded independently by two authors. RESULTS: Responses were received from 24 geriatricians via a combination of digital questionnaires (n=18) and semi-structured online interviews (n=6), for a response rate of 80%. Responses revealed significant diversity of opinion on how to define and identify frailty and how these concepts should be taught. CONCLUSIONS: As frailty is increasingly incorporated into clinical practice, consensus is needed on how to define and teach frailty to residents.


Assuntos
Fragilidade , Geriatria , Internato e Residência , Humanos , Idoso , Avaliação das Necessidades , Fragilidade/diagnóstico , Docentes
3.
Orig Life Evol Biosph ; 37(1): 1-2, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17203239
5.
Orig Life Evol Biosph ; 30(5): 405-10, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11002886

RESUMO

Electrical discharges in water-saturated N2 containing 1-10% CH4 were shown earlier to reduce phosphate to phosphite. This mechanism was suggested as a possible source of water-soluble phosphorus-containing compounds in volcanic environments on the prebiotic Earth. We have now extended our investigations to gas mixtures in which CO2 and N2 are the main components, and studied the effect of introducing small amounts of H2 and CO. We show that surprisingly high conversions to phosphite occur in reducing mixtures and that several percent reduction of apatite occurs even in the presence of as little as 1% each of H2 and CO. We were also able to confirm a previous report of polyphosphate production as a result of heating the mineral apatite in the presence of other minerals.


Assuntos
Planeta Terra , Evolução Química , Fosfatos , Eletricidade , Metano , Nitrogênio , Fosfatos/química , Água
6.
Scalpel Tongs ; 44: 6-11, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11624306
7.
Scalpel Tongs ; 44(3): 52-3, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11624489
12.
Orig Life Evol Biosph ; 29(6): 555-61, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10666740

RESUMO

If phosphorus played a role in the origin of life, some means of concentrating micromolar levels of phosphate (derived from the calcium phosphate mineral apatite), must first have been available. Here we show that simulated (mini)lightning discharges in model prebiotic atmospheres, including only minimally reducing ones, reduce orthophosphates, including apatite, to produce substantial yields of phosphite. Electrical discharges associated with volcanic eruptions could have provided a particularly suitable environment for this process. Production of relatively soluble and reactive phosphite salts could have supplied a pathway by which the first phosphorus atoms were incorporated into (pre)biological systems.


Assuntos
Apatitas , Origem da Vida , Fosfatos , Desastres , Planeta Terra , Raio , Oxirredução , Fosfitos
13.
J Mol Evol ; 47(5): 501-7, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9797400

RESUMO

Minerals may have played a significant role in chemical evolution. In the course of investigating the chemistry of phosphonoacetaldehyde (PAL), an analogue of glycolaldehyde phosphate, we have observed a striking case of catalysis by the layered hydroxide mineral hydrotalcite ([Mg2Al(OH)6][Cl.nH2O]). In neutral or moderately basic aqueous solutions, PAL is unreactive even at a concentration of 0.1 M. In the presence of a large excess of NaOH (2 M), the compound undergoes aldol condensation to produce a dimer containing a C3-C4 double-bond. In dilute neutral solutions and in the presence of the mineral, however, condensation takes place rapidly, to produce a dimer which is almost exclusively the C2-C3 unsaturated product.


Assuntos
Acetaldeído/análogos & derivados , Aldeídos/química , Hidróxido de Alumínio/química , Evolução Química , Hidróxido de Magnésio/química , Organofosfonatos/química , Acetaldeído/química , Catálise , Cromatografia Líquida de Alta Pressão , Dimerização , Espectroscopia de Ressonância Magnética , Organofosfonatos/síntese química , Hidróxido de Sódio/química , Análise Espectral
14.
Orig Life Evol Biosph ; 28(3): 271-82, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9611767

RESUMO

Phosphonoacetaldehyde (PAL), a phosphonic acid analogue of glycolaldehyde phosphate, reacts in the presence of formaldehyde under mildly basic conditions to produce several new products. The reaction proceeds in two stages: a fast aldol condensation of formaldehyde with PAL, and a slower reaction to produce products containing two phosphonic acid groups. We report on the derivatization, isolation by means of HPLC and characterization of these compounds. One of the products is of potential interest as a building block for a prebiotic informational polymer.


Assuntos
Acetaldeído/análogos & derivados , Formaldeído/química , Organofosfonatos/química , Organofosfonatos/síntese química , Acetaldeído/química , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas , Espectroscopia de Ressonância Magnética , Modelos Químicos
17.
J Theor Biol ; 187(4): 523-7, 1997 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-9299296

RESUMO

While no convincing prebiotic synthesis of RNA building blocks has been demonstrated, at least two synthetic analogues of nucleic acids have been described whose properties are remarkably similar to those of RNA. The RNA backbone is thus not the only possible solution to the problem of replicating the information stored in a sequence of purines and pyrmidines. These results indirectly support the suggestion that RNA might have been preceded in evolution by a related molecule which, perhaps, was more easily synthesized than RNA. New results on the prebiotic chemistry of phosphonic acids suggest a possibility that a backbone structure based on ribose-2,4-diphosphonic acid may have formed via some surprisingly simple chemistry.


Assuntos
Evolução Molecular , RNA/química , Animais , Modelos Biológicos , Modelos Químicos , Ácidos Nucleicos/química , Fosforilação
18.
Curr Biol ; 7(8): R477-9, 1997 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-9259546

RESUMO

Recent results show that the self-assembly of long homochiral oligomers of a nucleotide analogue can be achieved by ligation of short oligomers of chirally mixed composition. Do these results show how the RNA world might have arisen?


Assuntos
Origem da Vida , RNA/química , Sequência de Bases , Evolução Molecular , Modelos Biológicos , Modelos Químicos , Estrutura Molecular , Estereoisomerismo
19.
Scalpel Tongs ; 41: 39-42, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-11619080
20.
Orig Life Evol Biosph ; 27(5-6): 505-12, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11536839

RESUMO

The available evidence indicates that the origin of life on Earth certainly occurred earlier than 3.5 billion years ago and perhaps substantially earlier. The time available for the chemical evolution which must have preceded this event is more difficult to estimate. Both endogenic and exogenic contributions to chemical evolution have been considered; i.e., from chemical reactions in a primitive atmosphere, or by introduction in the interiors of comets and/or meteorites. It is argued, however, that the phosphorus chemistry of Earth's earliest hydrosphere, whether primarily exogenic or endogenic in origin, was most likely dominated by compounds less oxidized than phosphoric acid and its esters. A scenario is presented for the early production of a suite of reactive phosphonic acid derivatives, the properties of which may have foreshadowed the later appearance of biophosphates.


Assuntos
Evolução Química , Organofosfonatos/química , Ácidos Fosfínicos/química , Ácidos de Fósforo/química , Fósforo/química , Atmosfera , Meteoroides , Fosfinas/química , Fosfitos/química , Ácidos Fosfóricos/química
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