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1.
J Intern Med ; 287(3): 252-262, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31621967

RESUMO

Mass extinctions occur frequently in natural history. While studies of animals that became extinct can be informative, it is the survivors that provide clues for mechanisms of adaptation when conditions are adverse. Here, we describe a survival pathway used by many species as a means for providing adequate fuel and water, while also providing protection from a decrease in oxygen availability. Fructose, whether supplied in the diet (primarily fruits and honey), or endogenously (via activation of the polyol pathway), preferentially shifts the organism towards the storing of fuel (fat, glycogen) that can be used to provide energy and water at a later date. Fructose causes sodium retention and raises blood pressure and likely helped survival in the setting of dehydration or salt deprivation. By shifting energy production from the mitochondria to glycolysis, fructose reduced oxygen demands to aid survival in situations where oxygen availability is low. The actions of fructose are driven in part by vasopressin and the generation of uric acid. Twice in history, mutations occurred during periods of mass extinction that enhanced the activity of fructose to generate fat, with the first being a mutation in vitamin C metabolism during the Cretaceous-Paleogene extinction (65 million years ago) and the second being a mutation in uricase that occurred during the Middle Miocene disruption (12-14 million years ago). Today, the excessive intake of fructose due to the availability of refined sugar and high-fructose corn syrup is driving 'burden of life style' diseases, including obesity, diabetes and high blood pressure.


Assuntos
Evolução Biológica , Mudança Climática , Secas , Metabolismo Energético/fisiologia , Frutose/metabolismo , Animais , Dieta , Extinção Biológica , Hominidae , Humanos , Mutação
2.
Sci Total Environ ; 687: 1389-1400, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31412472

RESUMO

Although multistage hydraulic fracturing is routinely performed for the extraction of hydrocarbon resources from low permeability reservoirs, the downhole geochemical processes linked to the interaction of fracturing fluids with formation brine and reservoir mineralogy remain poorly understood. We present a geochemical dataset of flowback and produced water samples from a hydraulically fractured reservoir in the Montney Formation, Canada, analyzed for major and trace elements and stable isotopes. The dataset consists in 25 samples of flowback and produced waters from a single well, as well as produced water samples from 16 other different producing wells collected in the same field. Additionally, persulfate breaker samples as well as anhydrite and pyrite from cores were also analyzed. The objectives of this study were to understand the geochemical interactions between formation and fracturing fluids and their consequences in the context of tight gas exploitation. The analysis of this dataset allowed for a comprehensive understanding of the coupled downhole geochemical processes, linked in particular to the action of the oxidative breaker. Flowback fluid chemistries were determined to be the result of mixing of formation brine with the hydraulic fracturing fluids as well as coupled geochemical reactions with the reservoir rock such as dissolution of anhydrite and dolomite; pyrite and organic matter oxidation; and calcite, barite, celestite, iron oxides and possibly calcium sulfate scaling. In particular, excess sulfate in the collected samples was found to be mainly derived from anhydrite dissolution, and not from persulfate breaker or pyrite oxidation. The release of heavy metals from the oxidation activity of the breaker was detectable but concentrations of heavy metals in produced fluids remained below the World Health Organization guidelines for drinking water and are therefore of no concern. This is due in part to the co-precipitation of heavy metals with iron oxides and possibly sulfate minerals.

3.
Trends Genet ; 17(7): 414-8, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11418223

RESUMO

Almost a century ago, Wittgenstein pointed out that theory in science is intricately connected to language. This connection is not a frequent topic in the genomics literature. But a case can be made that functional genomics is today hindered by the paradoxes that Wittgenstein identified. If this is true, until these paradoxes are recognized and addressed, functional genomics will continue to be limited in its ability to extrapolate information from genomic sequences.


Assuntos
Biologia Computacional/métodos , Evolução Molecular , Proteínas/química , Proteínas/metabolismo , Sequência de Aminoácidos , Animais , Genômica , Humanos , Linguística , Dados de Sequência Molecular , Filogenia , Proteínas/genética , Alinhamento de Sequência , Especificidade por Substrato
4.
Proc Natl Acad Sci U S A ; 98(2): 548-52, 2001 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-11209054

RESUMO

The divergent evolution of protein sequences from genomic databases can be analyzed by the use of different mathematical models. The most common treat all sites in a protein sequence as equally variable. More sophisticated models acknowledge the fact that purifying selection generally tolerates variable amounts of amino acid replacement at different positions in a protein sequence. In their "stationary" versions, such models assume that the replacement rate at individual positions remains constant throughout evolutionary history. "Nonstationary" covarion versions, however, allow the replacement rate at a position to vary in different branches of the evolutionary tree. Recently, statistical methods have been developed that highlight this type of variation in replacement rates. Here, we show how positions that have variable rates of divergence in different regions of a tree ("covarion behavior"), coupled with analyses of experimental three-dimensional structures, can provide experimentally testable hypotheses that relate individual amino acid residues to specific functional differences in those branches. We illustrate this in the elongation factor family of proteins as a paradigm for applications of this type of analysis in functional genomics generally.


Assuntos
Evolução Molecular , Fator 1 de Elongação de Peptídeos/fisiologia , Fator Tu de Elongação de Peptídeos/fisiologia , Sequência de Aminoácidos , Animais , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/fisiologia , Sítios de Ligação , Simulação por Computador , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Proteínas Fúngicas/fisiologia , Humanos , Proteínas de Insetos/química , Proteínas de Insetos/genética , Proteínas de Insetos/fisiologia , Modelos Genéticos , Modelos Moleculares , Dados de Sequência Molecular , Fator 1 de Elongação de Peptídeos/química , Fator 1 de Elongação de Peptídeos/genética , Fator Tu de Elongação de Peptídeos/química , Fator Tu de Elongação de Peptídeos/genética , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/fisiologia , Conformação Proteica , Proteínas de Protozoários/química , Proteínas de Protozoários/genética , Proteínas de Protozoários/fisiologia , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Especificidade da Espécie , Relação Estrutura-Atividade
5.
Proc Natl Acad Sci U S A ; 95(12): 6897-902, 1998 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-9618510

RESUMO

The soybean genome hosts a family of several hundred, relatively homogeneous copies of a large, copia/Ty1-like retroelement designated SIRE-1. A copy of this element has been recovered from a Glycine max genomic library. DNA sequence analysis of two SIRE-1 subclones revealed that SIRE-1 contains a long, uninterrupted, ORF between the 3' end of the pol ORF and the 3' long terminal repeat (LTR), a region that harbors the env gene in retroviral genomes. Conceptual translation of this second ORF produces a 70-kDa protein. Computer analyses of the amino acid sequence predicted patterns of transmembrane domains, alpha-helices, and coiled coils strikingly similar to those found in mammalian retroviral envelope proteins. In addition, a 65-residue, proline-rich domain is characterized by a strong amino acid compositional bias virtually identical to that of the 60-amino acid, proline-rich neutralization domain of the feline leukemia virus surface protein. The assignment of SIRE-1 to the copia/Ty1 family was confirmed by comparison of the conceptual translation of its reverse transcriptase-like domain with those of other retroelements. This finding suggests the presence of a proretrovirus in a plant genome and is the strongest evidence to date for the existence of a retrovirus-like genome closely related to copia/Ty1 retrotransposons.


Assuntos
Elementos de DNA Transponíveis/genética , Genoma de Planta , Genoma Viral , Glycine max/genética , Retroviridae/genética , Proteínas do Envelope Viral/genética , Sequência de Aminoácidos , Animais , Gatos , Clonagem Molecular , Dados de Sequência Molecular , Alinhamento de Sequência , Análise de Sequência
10.
Qual Lett Healthc Lead ; 5(10): 19-23, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-10131336

RESUMO

Administrative simplification is a key element of the Clinton healthcare reform proposal. Healthcare leaders, however, "cannot lay the entire burden of administrative simplification on outsiders," says Ellen J. Gaucher, Senior Associate Director of The University of Michigan Hospitals. There are numerous opportunities to use the principles of total quality management to improve operational and financial performance in healthcare organizations.


Assuntos
Administração Hospitalar/normas , Gestão da Qualidade Total/organização & administração , Eficiência Organizacional , Reforma dos Serviços de Saúde/legislação & jurisprudência , Formulação de Políticas , Avaliação de Processos em Cuidados de Saúde/normas , Estados Unidos , Simplificação do Trabalho
11.
Clin Lab Manage Rev ; 7(4): 388, 385-7, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-10127169

RESUMO

When we talk about world-class health care, we are finding that we are in a position where the purchasers of our services find there is little or no value for the health-care dollars they are spending. Even the father of American Quality, W. Edwards Deming, has listed the high cost of health care as one of the seven deadly diseases, so we know that we are in trouble. According to a 1989 study, the public tells us that 32% of the time the value of health care they receive is good to excellent, and 65% of the time it is fair to poor. When we look at what our physicians say, 76% of them believe that we get good value for health-care dollars as opposed to 23% who think it is fair to poor. As I have been thinking about what world-class quality would mean, one of the things that comes to mind is the fact that health care is now consuming 15% of the gross national product. We are approaching an expenditure level of one trillion dollars. If our results were good, we could feel comfortable resting on our laurels, because for those we serve in the American health-care system, we serve them very well. But our results are not good. We are 23rd in the world in infant mortality, and we are 16th in the world for life expectancy. The real tragedy in the American health-care system is that 37 million Americans are uninsured. Obviously this cannot continue.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Modelos Organizacionais , Garantia da Qualidade dos Cuidados de Saúde , Técnicas de Planejamento , Estados Unidos
12.
Qual Lett Healthc Lead ; 5(5): 8-10, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10126928

RESUMO

UNLABELLED: Project Overview: In April 1990, The University of Michigan Hospitals began a major, multidisciplinary project to standardize care processes in order to increase efficiency and reduce costs while maintaining the quality of clinical care. A team of nurses began the project by developing critical pathways for two neurosurgery procedures--lumbar laminectomy and transphenoidal pituitary tumor resection. The pathways were reviewed by physicians and other staff from other disciplines and were implemented in January of 1991. KEY FINDINGS: Data from the first 14 months show a decrease in patients' average lengths of stay in both the intensive care unit (ICU) and routine care unit. Costs and variance data are being analyzed and further improvements to the pathways are being made. Eleven critical paths are now being used for neurosurgery patients. In retrospect, participants learned that physicians should be involved at the earliest stages of critical pathway development and in the process of implementation.


Assuntos
Protocolos Clínicos/normas , Neurocirurgia/normas , Centro Cirúrgico Hospitalar/normas , Centros Médicos Acadêmicos/normas , Coleta de Dados , Humanos , Laminectomia/normas , Vértebras Lombares/cirurgia , Michigan , Neurocirurgia/economia , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Neoplasias Hipofisárias/cirurgia , Garantia da Qualidade dos Cuidados de Saúde/organização & administração , Centro Cirúrgico Hospitalar/economia
14.
Top Hosp Pharm Manage ; 12(4): 70-84, 1993 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10128766

RESUMO

While the barriers to TQM implementation are many and the lessons learned can be very painful, we are convinced the results are well worth the effort. TQM implementation is a long term strategic approach and while results can be fairly quick, organizational cultural change and strategic redirection take time. Progress can be very slow. By reducing waste, rework, and variation we can both improve quality and reduce cost. The ultimate goal of TQM is to have organizational members using the quality tools in their daily work life. As an increasing number of health care organizations move through the four phases of implementation, sharing lessons learned can help us understand how to evaluate our quality processes and sustain the improvement process.


Assuntos
Hospitais Universitários/normas , Desenvolvimento de Programas/normas , Garantia da Qualidade dos Cuidados de Saúde/organização & administração , Comportamento do Consumidor , Hospitais com mais de 500 Leitos , Hospitais Universitários/organização & administração , Relações Interdepartamentais , Liderança , Participação nas Decisões , Michigan , Inovação Organizacional , Desenvolvimento de Pessoal , Análise e Desempenho de Tarefas
15.
Qual Manag Health Care ; 1(3): 10-8, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-10130523

RESUMO

Quality experts state that ineffective leadership can hinder and even destroy efforts to implement total quality management (TQM). However, they rarely discuss the specific actions leaders should take in implementing TQM and when leaders should take them. This article discusses a four-phase TQM implementation model that includes specifications for leadership actions at each step.


Assuntos
Administradores Hospitalares , Liderança , Gestão da Qualidade Total/organização & administração , Tomada de Decisões Gerenciais , Hospitais Universitários/organização & administração , Hospitais Universitários/normas , Humanos , Michigan , Modelos Organizacionais , Inovação Organizacional , Comunicação Persuasiva , Técnicas de Planejamento , Desenvolvimento de Programas , Papel (figurativo)
16.
Healthc Forum J ; 35(1): 56-60, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-10116129

RESUMO

In 1987, Ellen Gaucher took an unusual trip. As senior associate director of the University of Michigan's sprawling 11,000-employee Medical Center, she was invited to a conference about a movement that was rapidly growing in the word of business--total quality. The occasion was the organizational conference of the National Demonstration Project on Quality Improvement in Health Care, led by the Harvard Community Health Plan in Boston. Gaucher was skeptical at first. Total quality seemed a great way to make better cars, light bulbs, and aluminum siding, but would it work in a service industry? More to the point, would it work in an industry as complex, as critical, as pressured, as high-tech, as human, and as intellectual as healthcare? But by the second day, she says, "I was sold that this was what we had needed for a long time." She hurried back to Michigan like a missionary trekking into cannibal country. Today, not only is the University Medical Center deep in a total quality conversion experience, so is the University itself, through its president, James J. Duderstadt. He was exposed to the idea through Gaucher: In his ex-officio position as chairman of the Medical Center's board, he had experienced her vivid and enthusiastic educational efforts. Gaucher has related her intense experiences with TQ at conferences, in articles, in the 1990 book, Transforming Healthcare Organizations (winner of the Hamilton Award given by the American College of Healthcare Executives for the best book of the year) as well as the forthcoming Total Quality in Healthcare (both co-authored with Richard Coffey). (ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Participação nas Decisões/organização & administração , Cultura Organizacional , Administração de Recursos Humanos em Hospitais/normas , Garantia da Qualidade dos Cuidados de Saúde/organização & administração , Serviço Hospitalar de Admissão de Pacientes/normas , Comportamento do Consumidor/economia , Redução de Custos/métodos , Eficiência , Hospitais com mais de 500 Leitos , Michigan , Alta do Paciente/normas , Resolução de Problemas
17.
J Nurs Adm ; 18(12): 20-2, 1988 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3057132

RESUMO

Seeking ways to produce new products, processes, and programs that would result in cost savings or increased revenue for nursing services and the institution, as well as attracting and retaining bright, creative nursing employees, the authors developed a pilot program to allow intrapreneurs to "run with" their ideas. The authors discuss the mechanics of their program development, implementation, and evaluation as well as examples of innovative projects under development by nursing employees.


Assuntos
Criatividade , Marketing de Serviços de Saúde , Recursos Humanos de Enfermagem Hospitalar , Hospitais com mais de 500 Leitos , Humanos , Mentores , Michigan , Inovação Organizacional , Projetos Piloto , Técnicas de Planejamento
20.
Paris; Octave Doin; 1910. 735 p. ilus.
Monografia em Francês | Coleciona SUS, IMNS | ID: biblio-922907
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