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1.
Nature ; 620(7973): 434-444, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37468638

RESUMO

Advances in DNA sequencing and machine learning are providing insights into protein sequences and structures on an enormous scale1. However, the energetics driving folding are invisible in these structures and remain largely unknown2. The hidden thermodynamics of folding can drive disease3,4, shape protein evolution5-7 and guide protein engineering8-10, and new approaches are needed to reveal these thermodynamics for every sequence and structure. Here we present cDNA display proteolysis, a method for measuring thermodynamic folding stability for up to 900,000 protein domains in a one-week experiment. From 1.8 million measurements in total, we curated a set of around 776,000 high-quality folding stabilities covering all single amino acid variants and selected double mutants of 331 natural and 148 de novo designed protein domains 40-72 amino acids in length. Using this extensive dataset, we quantified (1) environmental factors influencing amino acid fitness, (2) thermodynamic couplings (including unexpected interactions) between protein sites, and (3) the global divergence between evolutionary amino acid usage and protein folding stability. We also examined how our approach could identify stability determinants in designed proteins and evaluate design methods. The cDNA display proteolysis method is fast, accurate and uniquely scalable, and promises to reveal the quantitative rules for how amino acid sequences encode folding stability.


Assuntos
Biologia , Engenharia de Proteínas , Dobramento de Proteína , Proteínas , Aminoácidos/genética , Aminoácidos/metabolismo , Biologia/métodos , DNA Complementar/genética , Estabilidade Proteica , Proteínas/química , Proteínas/genética , Proteínas/metabolismo , Termodinâmica , Proteólise , Engenharia de Proteínas/métodos , Domínios Proteicos/genética , Mutação
2.
Am J Chin Med ; 48(4): 899-921, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32431179

RESUMO

In Chinese medicine, fermentation is a highly important processing technology whereby medicinal herbs are fermented under appropriate temperature, humidity, and moisture conditions by means of the action of microorganisms to enhance their original characteristics and/or produce new effects. This expands the scope of such medicines and helps them to meet the stringent demands of clinical application. Since ancient times, Chinese medicine has been made into Yaoqu to reduce its toxicity and increase its efficiency. Modern fermentation technologies have been developed on the basis of traditional fermentation techniques and modern biological technology, and they can be divided into solid fermentation, liquid fermentation, and two-way fermentation technologies according to the fermentation form employed. This review serves as an introduction to traditional fermentation technology and its related products, modern fermentation technologies, and the application of fermentation technology in the field of Chinese medicine. Several problems and challenges facing the field are also briefly discussed.


Assuntos
Biologia/métodos , Medicamentos de Ervas Chinesas , Fermentação , Medicina Tradicional Chinesa/métodos , Extratos Vegetais
3.
J Hist Biol ; 51(1): 31-67, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28255641

RESUMO

It is time to escape the constraints of the Systematics Wars narrative and pursue new questions that are better positioned to establish the relevance of the field in this time period to broader issues in the history of biology and history of science. To date, the underlying assumptions of the Systematics Wars narrative have led historians to prioritize theory over practice and the conflicts of a few leading theorists over the less-polarized interactions of systematists at large. We show how shifting to a practice-oriented view of methodology, centered on the trajectory of mathematization in systematics, demonstrates problems with the common view that one camp (cladistics) straightforwardly "won" over the other (phenetics). In particular, we critique David Hull's historical account in Science as a Process by demonstrating exactly the sort of intermediate level of positive sharing between phenetic and cladistic theories that undermines their mutually exclusive individuality as conceptual systems over time. It is misleading, or at least inadequate, to treat them simply as holistically opposed theories that can only interact by competition to the death. Looking to the future, we suggest that the concept of workflow provides an important new perspective on the history of mathematization and computerization in biology after World War II.


Assuntos
Biologia/história , Classificação/métodos , Biologia/métodos , História do Século XX
4.
Prog Biophys Mol Biol ; 119(3): 481-92, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26236011

RESUMO

In this article we challenge the pervasive notion of hierarchy in biological and cognitive systems and delineate the basis for a complementary heterarchical approach starting from the seminal ideas of Warren McCullock and Gregory Bateson. We intend these considerations as a contribution to the different scientific disciplines working towards a multilevel integrative perspective of biological and cognitive processes, such as systems and integrative biology and neuroscience, social and cultural neuroscience, social signal transduction and psychoneuroimmunology, for instance. We argue that structures and substrates are by necessity organized hierarchically, while communication processes - and their embeddedness - are rather organized heterarchically. Before getting into the implications of the heterarchical approach and its congeniality with the semiotic perspective to biology and cognition, we introduce a set of notions and concepts in order to advance a framework that considers the heterarchical embeddedness of different layers of physiological, behavioral, affective, cognitive, technological and socio-cultural levels implicit in networks of interacting minds, considering the dynamic complementarity of bottom-up and top-down causal links. This should contribute to account for the integration, interpretation and response to complex aggregates of information at different levels of organization in a developmental context. We illustrate the dialectical nature of embedded heterarchical processes by addressing the simultaneity and circularity of cognition and volition, and how such dialectics can be present in primitive instances of proto-cognition and proto-volition, giving rise to our claim that subjectivity and semiotic freedom are scalar properties. We collate the framework with recent empirical systemic approaches to biology and integrative neuroscience, and conclude with a reflection on its implications to the understanding of the emergence of pathological conditions in multi-level semiotic systems.


Assuntos
Biologia/métodos , Cognição , Humanos
5.
Curr Opin Chem Biol ; 17(3): 329-38, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23683346

RESUMO

Academic screening centers across the world have endeavored to discover small molecules that can modulate biological systems. To increase the reach of functional-genomic and chemical screening programs, universities, research institutes, and governments have followed their industrial counterparts in adopting high-throughput paradigms. As academic screening efforts have steadily grown in scope and complexity, so have the ideas of what is possible with the union of technology and biology. This review addresses the recent conceptual and technological innovation that has been propelling academic screening into its own unique niche. In particular, high-content and whole-organism screening are changing how academics search for novel bioactive compounds. Importantly, we recognize examples of successful chemical probe development that have punctuated the changing technology landscape.


Assuntos
Biologia/métodos , Química/métodos , Avaliação Pré-Clínica de Medicamentos/métodos , Animais , Ensaios de Triagem em Larga Escala , Humanos , Indústrias , Fenótipo
6.
Methods Mol Biol ; 967: 99-113, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23296724

RESUMO

The JAK family of protein tyrosine kinases are now recognized as important participants in a wide range of pathologies, from cancer to inflammatory diseases. In the last decade, the drive to develop drugs targeting members of this family has begun to deliver a panel of small molecule inhibitors of JAK family members, with a range of potencies and specificities. A number of these compounds have already found widespread use as biochemical tools in the elucidation of JAK activity in specific signaling and disease processes; however, many of the first generation compounds are poorly characterized with suboptimal potencies and selectivities.Herein, we present the data for those small molecule JAK inhibitors that have been described in the peer-reviewed literature and the benefits and potential issues that may be associated with the use of these tool compounds.


Assuntos
Biologia/métodos , Química/métodos , Janus Quinases/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Avaliação Pré-Clínica de Medicamentos , Humanos , Inibidores de Proteínas Quinases/química
7.
Methods Mol Biol ; 950: 209-26, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23086878

RESUMO

Over the past decades there have been significant advances in transmission electron microscopy for biological applications, including in energy filtering and spectrum imaging, which are techniques based on the principles of electron energy loss spectroscopy. These imaging modalities allow quantitative mapping of specific chemical elements with high sensitivity and spatial resolution. This chapter describes the experimental and computational procedures for elemental mapping in two dimensions as well as a more recent extension to three dimensions, which can reveal quantitative distributions of elements in cells on a macromolecular scale.


Assuntos
Biologia/métodos , Elementos Químicos , Espectroscopia de Perda de Energia de Elétrons/métodos , Animais , Caenorhabditis elegans/citologia , DNA/metabolismo , Drosophila melanogaster/citologia , Drosophila melanogaster/embriologia , Embrião não Mamífero/citologia , Embrião não Mamífero/metabolismo , Imageamento Tridimensional , Microscopia Eletrônica de Transmissão/instrumentação , Fósforo/metabolismo , Estatística como Assunto , Timócitos/citologia , Timócitos/ultraestrutura
8.
Cryo Letters ; 32(4): 287-96, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22020408

RESUMO

The droplet vitrification method was improved for maneuverability by embedding shoot tips in gelled droplets before osmoprotection. This newly modified cryopreserving method -gelled droplet vitrification - was compared with other PVS2-based cryopreservation methods using potato shoot tips. Survival rates of each cryogenic procedure held at 25 degree C were about 40 percent by cryotube-vitrification procedures (vitrification and encapsulation vitrification methods) and about 70 percent by PVS2-droplet procedures (droplet vitrification and gelled droplet vitrification methods). Much higher cooling rates of PVS2-droplet procedures than cryotube- vitrification procedures increased their survival rates. The gelled droplet vitrification method was applied to shoot tips of 26 potato cultivars and six wild potatoes. After a little modifications of the conditions for preculture, osmoprotection and dehydration, all cultivars and wild potatoes produced high enough survival rates to be of value to genebanks and all surviving shoot tips developed normal shoots within 3 weeks.


Assuntos
Criopreservação/métodos , Brotos de Planta/crescimento & desenvolvimento , Solanum tuberosum/fisiologia , Biologia/métodos , Botânica/métodos , Temperatura Baixa , Crioprotetores/farmacologia , Meios de Cultura/farmacologia , Técnicas de Cultura/métodos , Brotos de Planta/fisiologia , Solanum tuberosum/embriologia , Temperatura , Vitrificação
9.
Zhongguo Zhong Yao Za Zhi ; 36(2): 228-31, 2011 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-21506427

RESUMO

In this article, we introduced the concept and technology of network biology and network pharmacology, and proposed the possible strategy for building the methodology for discovering and developing Chinese medicine based on network biology. The concept of network pharmacology of Chinese medicine and its potential application in the modernization of traditional Chinese medicine was also discussed.


Assuntos
Biologia/métodos , Medicina Tradicional Chinesa/métodos , Animais , Tratamento Farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Humanos
10.
Curr Opin Struct Biol ; 20(4): 497-507, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20471246

RESUMO

Fragment-based ligand screening is now established as an emerging paradigm for drug discovery. Here we examine the recent literature looking at how structural biology has been used in a variety of successful fragment-screening applications. We argue that the determination of experimental binding modes has proved to be one of the mainstays of successful fragment-based approaches and that this reflects the difficulty in optimising a fragment to a lead molecule in the absence of structural information. We focus on antimicrobial research where fragment-based drug discovery allows control of the physical properties of the emerging lead molecule.


Assuntos
Biologia/métodos , Desenho de Fármacos , Animais , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Cristalografia por Raios X , Avaliação Pré-Clínica de Medicamentos , Humanos , Espectroscopia de Ressonância Magnética
11.
Biochem Soc Trans ; 38(2): 641-4, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20298236

RESUMO

Between 21 and 25 September 2009, Krakow hosted the 4th Conference of the Polish Society of Experimental Plant Biology, co-organized with the Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, and supported by the Biochemical Society. The aim of the conference was to present and discuss the most important topics in different disciplines of plant experimental science as well as to facilitate the interaction and co-operation between scientists. To achieve this goal, about 30 top specialists in various areas of plant biology were invited to give plenary lectures in the following sessions: Plant structure and development; Plant-microbial interactions; Mitochondria and chloroplasts in cell metabolism; Stress tolerance in plants; Structural and functional organization of plant genomes; Mutants in developmental and metabolic studies; Secondary metabolites as pharmaceutics and nutraceutics; Plant membranes; and Integrating plant functions via signalling molecules: molecular mechanisms. Some of the main problems highlighted in the plenary lectures are briefly summarized in the present paper. Two poster sessions enabled a discussion of over 200 posters presented. The conference had an international character, its official language was English, and among the more than 350 participants, about 60 were from abroad. Several plenary lectures were prepared as short review papers and they are published in this issue of Biochemical Society Transactions.


Assuntos
Biologia/tendências , Fenômenos Fisiológicos Vegetais , Adaptação Biológica/genética , Adaptação Biológica/fisiologia , Biologia/métodos , Membrana Celular/genética , Membrana Celular/metabolismo , Células/metabolismo , Células/ultraestrutura , Cloroplastos/metabolismo , Cloroplastos/fisiologia , Suplementos Nutricionais , Genoma de Planta/genética , Interações Hospedeiro-Patógeno/fisiologia , Mitocôndrias/metabolismo , Mitocôndrias/fisiologia , Estruturas Vegetais/embriologia , Estruturas Vegetais/crescimento & desenvolvimento , Estruturas Vegetais/fisiologia , Plantas/microbiologia , Plantas/ultraestrutura , Plantas Geneticamente Modificadas , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Estresse Fisiológico/fisiologia
12.
Med Sci (Paris) ; 25 Spec No 2: 39-42, 2009 May.
Artigo em Francês | MEDLINE | ID: mdl-19852087

RESUMO

Integrative biology currently undergoes a deep renewal as we witness the increasing influence of systems biology, which explores life's logic, and of synthetic biology, which exploits it.


Assuntos
Biologia/métodos , Genética/tendências , Medicina Integrativa/métodos , Biologia de Sistemas/tendências , Animais , Biologia/tendências , Biotecnologia/métodos , Biotecnologia/tendências , Escherichia coli/genética , Humanos , Medicina Integrativa/tendências
13.
Electromagn Biol Med ; 28(1): 61-70, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19337896

RESUMO

Since antiquity, biology has had two opposing views of life and organisms: holistic (organismic) and reductionist. In contemporary biology, the molecular reductionist approach prevails--its central entity being the gene. Organicism lingers on the margin of biology, having well-elaborated ideas but no empirical confirmation for the integrative biological entity. The latter could be found in the endogenous coherent EM field (ECEMF), since it organizes countless cellular processes, including cell's division, and through the coupling of coherence domains integrates the whole organism. A serious and thorough reconsideration of life and organisms in light of this new biological entity would have far-reaching consequences in all areas of biological science, i.e., in ontogeny, the theory of evolution, understanding and combating serious illnesses, and above all, cancer.


Assuntos
Pesquisa Biomédica/tendências , Campos Eletromagnéticos , Efeitos da Radiação , Animais , Disciplinas das Ciências Biológicas , Biologia/métodos , Biofísica/métodos , Divisão Celular , Humanos , Modelos Biológicos , Modelos Teóricos
15.
Expert Opin Biol Ther ; 8(7): 923-40, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18549323

RESUMO

BACKGROUND: Spongiform neurodegeneration is the pathological hallmark of individuals suffering from prion disease. These disorders, whose manifestation is sporadic, familial or acquired by infection, are caused by accumulation of the aberrantly folded isoform of the cellular prion protein (PrP(c)), termed PrP(Sc). Although usually rare, prion disorders are inevitably fatal and transferrable by infection. OBJECTIVE: Pathology is restricted to the central nervous system and premortem diagnosis is usually not possible. Yet, promising approaches towards developing therapeutic regimens have been made recently. METHODS: The biology of prion proteins and current models of neurotoxicity are discussed and prophylactic and therapeutic concepts are introduced. RESULTS/CONCLUSIONS: Although various promising drug candidates with antiprion activity have been identified, this proof-of-concept cannot be transferred into translational medicine yet.


Assuntos
Doenças Neurodegenerativas/metabolismo , Príons/metabolismo , Animais , Biologia/métodos , Síndrome de Creutzfeldt-Jakob/terapia , Desenho de Fármacos , Avaliação Pré-Clínica de Medicamentos , Humanos , Camundongos , Modelos Biológicos , Proteínas PrPC/química , Proteínas PrPSc/química , Doenças Priônicas/terapia , Conformação Proteica , Isoformas de Proteínas
16.
Brief Funct Genomic Proteomic ; 7(4): 239-48, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18579616

RESUMO

Systems biology represents an experimental approach to biology that attempts to study biological systems in a holistic rather than an atomistic manner. Ideally this involves gathering dynamic and global data sets as well as phenotypic data from different levels of the biological information hierarchy, integrating them and modeling them graphically and/or mathematically to generate mechanistic explanations for the emergent systems properties. This requires that the biological frontiers drive the development of new measurement and visualization technologies and the pioneering of new computational and mathematical tools-all of which requires a cross-disciplinary environment composed of biologists, chemists, computer scientists, engineers, mathematicians, physicists, and physicians speaking common discipline languages. The Institute for Systems Biology has aspired to pioneer and seamlessly integrate each of these concepts.


Assuntos
Biologia de Sistemas/métodos , Biologia de Sistemas/tendências , Academias e Institutos , Animais , Biologia/métodos , Biologia/tendências , Halobacterium salinarum/genética , Humanos , Imunidade , Inflamação/fisiopatologia , Ciência da Informação , Internet , Peroxissomos/fisiologia , Pesquisa , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/fisiologia
17.
Physiol Plant ; 132(1): 11-22, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18251866

RESUMO

Plant oils represent renewable sources of long-chain hydrocarbons that can be used as both fuel and chemical feedstocks, and genetic engineering offers an opportunity to create further high-value specialty oils for specific industrial uses. While many genes have been identified for the production of industrially important fatty acids, expression of these genes in transgenic plants has routinely resulted in a low accumulation of the desired fatty acids, indicating that significantly more knowledge of seed oil production is required before any future rational engineering designs are attempted. Here, we provide an overview of the cellular features of fatty acid desaturases, the so-called diverged desaturases, and diacylglycerol acyltransferases, three sets of enzymes that play a central role in determining the types and amounts of fatty acids that are present in seed oil, and as such, the final application and value of the oil. Recent studies of the intracellular trafficking, assembly and regulation of these enzymes have provided new insights to the mechanisms of storage oil production, and suggest that the compartmentalization of enzyme activities within specific regions or subdomains of the ER may be essential for both the synthesis of novel fatty acid structures and the channeling of these important fatty acids into seed storage oils.


Assuntos
Ração Animal , Óleos de Plantas , Plantas/genética , Biologia/métodos , Fenômenos Fisiológicos Celulares , Clonagem Molecular , Óleos Combustíveis , Genes de Plantas , Engenharia Genética/métodos , Petróleo , Proteínas de Plantas/genética , Projetos de Pesquisa
20.
BMC Mol Biol ; 7: 5, 2006 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-16483373

RESUMO

BACKGROUND: Circadian rhythms are endogenous, self-sustained oscillations with approximately 24-hr rhythmicity that are manifested in various physiological and metabolic processes. The circadian organization of these processes in mammals is governed by the master oscillator within the suprachiasmatic nuclei (SCN) of the hypothalamus. Recent findings revealed that circadian oscillators exist in most organs, tissues, and even in immortalized cells, and that the oscillators in peripheral tissues are likely to be coordinated by SCN, the master oscillator. Some candidates for endogenous entrainment factors have sporadically been reported, however, their details remain mainly obscure. RESULTS: We developed the in vitro real-time oscillation monitoring system (IV-ROMS) by measuring the activity of luciferase coupled to the oscillatory gene promoter using photomultiplier tubes and applied this system to screen and identify factors able to influence circadian rhythmicity. Using this IV-ROMS as the primary screening of entrainment factors for circadian clocks, we identified 12 candidates as the potential entrainment factor in a total of 299 peptides and bioactive lipids. Among them, four candidates (endothelin-1, all-trans retinoic acid, 9-cis retinoic acid, and 13-cis retinoic acid) have already been reported as the entrainment factors in vivo and in vitro. We demonstrated that one of the novel candidates, 15-deoxy-Delta12,14-prostaglandin J2 (15d-PGJ2), a natural ligand of the peroxisome proliferator-activated receptor-gamma (PPAR-gamma), triggers the rhythmic expression of endogenous clock genes in NIH3T3 cells. Furthermore, we showed that 15d-PGJ2 transiently induces Cry1, Cry2, and Roralpha mRNA expressions and that 15d-PGJ2-induced entrainment signaling pathway is PPAR-gamma--and MAPKs (ERK, JNK, p38MAPK)-independent. CONCLUSION: Here, we identified 15d-PGJ2 as an entrainment factor in vitro. Using our developed IV-ROMS to screen 299 compounds, we found eight novel and four known molecules to be potential entrainment factors for circadian clocks, indicating that this assay system is a powerful and useful tool in initial screenings.


Assuntos
Ritmo Circadiano , Técnicas Genéticas , Oscilometria , Animais , Animais Geneticamente Modificados , Biologia/métodos , Proteínas de Ciclo Celular , Linhagem Celular , Sistemas Computacionais , Fibroblastos/metabolismo , Regulação da Expressão Gênica , Hipotálamo/fisiologia , Hibridização In Situ , Técnicas In Vitro , Luciferases/metabolismo , Camundongos , Células NIH 3T3 , Proteínas Nucleares/genética , PPAR gama/metabolismo , Peptídeos/química , Proteínas Circadianas Period , Fotoperíodo , Regiões Promotoras Genéticas , Prostaglandina D2/análogos & derivados , Prostaglandina D2/metabolismo , RNA Mensageiro/metabolismo , Ratos , Transdução de Sinais , Núcleo Supraquiasmático/fisiologia , Fatores de Tempo , Fatores de Transcrição/genética , Regulação para Cima
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