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1.
Hum Brain Mapp ; 45(5): e26635, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38544425

RESUMEN

The superior frontal sulcus (SFS) is the major sulcus on the dorsolateral frontal cortex that defines the lateral limit of the superior frontal gyrus. Caudally, it originates near the superior precentral sulcus (SPRS) and, rostrally, it terminates near the frontal pole. The advent of structural neuroimaging has demonstrated significant variability in this sulcus that is not captured by the classic sulcal maps. The present investigation examined the morphological variability of the SFS in 50 individual magnetic resonance imaging (MRI) scans of the human brain that were registered to the Montreal Neurological Institute (MNI) standard stereotaxic space. Two primary morphological patterns were identified: (i) the SFS was classified as a continuous sulcus or (ii) the SFS was a complex of sulcal segments. The SFS showed a high probability of merging with neighbouring sulci on the superior and middle frontal gyri and these patterns were documented. In addition, the morphological variability and spatial extent of the SFS were quantified using volumetric and surface spatial probability maps. The results from the current investigation provide an anatomical framework for understanding the morphology of the SFS, which is critical for the interpretation of structural and functional neuroimaging data in the dorsolateral frontal region, as well as for improving the accuracy of neurosurgical interventions.


Asunto(s)
Mapeo Encefálico , Encéfalo , Humanos , Mapeo Encefálico/métodos , Corteza Prefrontal , Lóbulo Frontal/diagnóstico por imagen , Lóbulo Frontal/anatomía & histología , Imagen por Resonancia Magnética , Probabilidad
2.
Front Plant Sci ; 14: 1174682, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37583596

RESUMEN

Cotton crop is known to be poorly adapted to waterlogging, especially during the early growth stages. Developing functional relationships between crop growth and development parameters and the duration of waterlogging is essential to develop or improve existing cotton crop models for simulating the impact of waterlogging. However, there are only limited experimental studies conducted on cotton specifically aimed at developing the necessary functional relationships required for waterlogging modeling. Further research is needed to understand the effects of waterlogging on cotton crops and improve modeling capabilities in this area. The current study aimed to conduct waterlogging experiments and develop functional relationships between waterlogging and cotton growth and physiology. The experiments were conducted in pots, and the waterlogging was initiated by plugging the drain hole at the bottom of the pot using a wooden peg. In the experiments, eight waterlogging treatments, including the control treatment, were imposed at the vegetative growth stage (15 days after sowing). Control treatment had zero days of water-logged condition; other treatments had 2, 4, 6, 8, 10, 12, and 14 days of waterlogging. It took five days to reach zero oxygen levels and one to two days to return to control after the treatment. After a total treatment duration of 14 days (30 days after sowing), the growth, physiological, reproductive, and nutrient analysis was conducted. All physiological parameters decreased with the number of days of waterlogging. Flavonoid and anthocyanin index increased with increased duration of waterlogging. Photosynthesis and whole plant dry weight in continuously waterlogged conditions were 75% and 78% less compared to 0, and 2-day water-logged plants. Plant height, stem diameter, number of main stem leaves, leaf area, and leaf length also decreased with waterlogging duration. When waterlogging duration increased, leaf, stem, and root macronutrients decreased, while micronutrients showed mixed trends. Based on the experimental study, functional relationships (linear, quadratic, and exponential decay) and waterlogging stress response indices are developed between growth and development parameters and the duration of waterlogging. This can serve as a base for developing or improving process-based cotton models to simulate the impact of waterlogging.

3.
Biomed Pharmacother ; 165: 115173, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37453200

RESUMEN

Nav1.1 is an important pharmacological target as this voltage-gated sodium channel is involved in neurological and cardiac syndromes. Channel activators are actively sought to try to compensate for haploinsufficiency in several of these pathologies. Herein we used a natural source of new peptide compounds active on ion channels and screened for drugs capable to inhibit channel inactivation as a way to compensate for decreased channel function. We discovered that JzTx-34 is highly active on Nav1.1 and subsequently performed a full structure-activity relationship investigation to identify its pharmacophore. These experiments will help interpret the mechanism of action of this and formerly identified peptides as well as the future identification of new peptides. We also reveal structural determinants that make natural ICK peptides active against Nav1.1 challenging to synthesize. Altogether, the knowledge gained by this study will help facilitate the discovery and development of new compounds active on this critical ion channel target.


Asunto(s)
Péptidos , Canales de Sodio Activados por Voltaje , Humanos , Péptidos/farmacología , Péptidos/química , Relación Estructura-Actividad
4.
Plants (Basel) ; 10(10)2021 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-34685904

RESUMEN

Short- and long-term waterlogging conditions impact crop growth and development, preventing crops from reaching their true genetic potential. Two experiments were conducted using a pot-culture facility to better understand soil waterlogging impacts on corn growth and development. Two corn hybrids were grown in 2017 and 2018 under ambient sunlight and temperature conditions. Waterlogging durations of 0, 2, 4, 6, 8, 10, 12, and 14 days were imposed at the V2 growth stage. Morphological (growth and development) and pigment estimation data were collected 15 days after treatments were imposed, 23 days after sowing. As waterlogging was imposed, soil oxygen rapidly decreased until reaching zero in about 8-10 days; upon the termination of the treatments, the oxygen levels recovered to the level of the 0 days treatment within 2 days. Whole-plant dry weight declined as the waterlogging duration increased, and after 2 days of waterlogging, a 44% and 27% decline was observed in experiments 1 and 2, respectively. Leaf area and root volume showed an exponential decay similar to the leaf and root dry weight. Leaf number and plant height were the least sensitive measured parameters and decreased linearly in both experiments. Root forks were the most sensitive parameter after 14 days of waterlogging in both experiments, declining by 83% and 80% in experiments 1 and 2, respectively. The data from this study improve our understanding of how corn plants react to increasing durations of waterlogging. In addition, the functional relationships generated from this study could enhance current corn simulation models for field applications.

5.
J Agric Food Chem ; 68(30): 7935-7945, 2020 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-32643372

RESUMEN

A cold-active transglutaminase (TGase, EC 2.3.2.13) that catalyzes the reaction of protein glutamine + protein lysine ↔ protein with γ-glutamyl-ε-lysine cross-link + NH3 at low temperatures was reported previously. This study verified the thermal stability of the TGase from 0-80 °C. Fluorescence and CD spectra studies confirmed tertiary structural damage at 40 °C, α-helix reduction at 60 °C, and refolding during cooling to 20 °C. The TGase sequence was obtained by transcriptomics and used to build its structure. Its catalytic triad was Cys333-His403-Asp426 and its catalytic process was inferred from the model. Molecular dynamics simulation illustrated that its cold activity resulted from its flexible active site, while high thermostability was conferred by an overall rigid structure, a large amount of stable Val and Lys, and strong electrostatic interactions at the N- and C- terminals. This study fills gaps in the correlation of conformational changes with stability and activity of TGase.


Asunto(s)
Proteínas de Artrópodos/química , Euphausiacea/enzimología , Transglutaminasas/química , Secuencias de Aminoácidos , Animales , Proteínas de Artrópodos/genética , Proteínas de Artrópodos/metabolismo , Biocatálisis , Dominio Catalítico , Frío , Estabilidad de Enzimas , Euphausiacea/química , Euphausiacea/genética , Calor , Cinética , Simulación de Dinámica Molecular , Replegamiento Proteico , Electricidad Estática , Transglutaminasas/genética , Transglutaminasas/metabolismo
6.
Chemistry ; 25(25): 6259-6269, 2019 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-30677177

RESUMEN

Proton-conducting materials in the solid state have received immense attention for their role as electrolytes in proton-exchange membrane fuel cells. Recently, crystalline materials-metal-organic frameworks (MOFs), hydrogen-bonded organic frameworks (HOFs), covalent organic frameworks (COFs), polyoxometalates (POMs), and porous organic crystals-have become an exciting research topic in the field of proton-conducting materials. For a better electrolyte, a high proton conductivity on the order of 10-2  S cm-1 or higher is preferred as efficient proton transport between the electrodes is ultimately necessary. With an emphasis on design principles, this Concept will focus on MOFs and other crystalline solid-based proton-conducting platforms that exhibit "ultrahigh superprotonic" conductivities with values in excess of 10-2  S cm-1 . While only a handful of MOFs exhibit such an ultrahigh conductivity, this quality in other systems is even rarer. In addition to interpreting the structural-functional correlation by taking advantage of their crystalline nature, we address the challenges and promising directions for future research.

7.
Arch Microbiol ; 201(2): 147-154, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30554292

RESUMEN

Peptides and proteins are important bioorganic compounds in nature, among which a special place is occupied by antimicrobial substances. There are more than 2000 different antimicrobial peptides (AMPs) produced by a variety of living organisms. Bacteriocins produced by bacteria are the minor group, whose chemical structures are most complicated among all AMPs. The review summarized the main points related to antimicrobial action of the bacteriocins including steps of peptide's interaction with bacterial membranes and details of membrane damaging. The membrane-disordered bacteriocins were described in accordance with structural-functional relationships.


Asunto(s)
Bacteriocinas/química , Bacterias/metabolismo , Bacteriocinas/metabolismo , Membrana Celular/metabolismo , Péptidos/metabolismo , Relación Estructura-Actividad
8.
Bioscience ; 68(4): 264-272, 2018 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-29686433

RESUMEN

Although there is a diversity of concerns about recent persistent declines in the abundances of many species, the implications for the associated delivery of ecosystem services to people are surprisingly poorly understood. In principle, there are a broad range of potential functional relationships between the abundance of a species or group of species and the magnitude of ecosystem-service provision. Here, we identify the forms these relationships are most likely to take. Focusing on the case of birds, we review the empirical evidence for these functional relationships, with examples of supporting, regulating, and cultural services. Positive relationships between abundance and ecosystem-service provision are the norm (although seldom linear), we found no evidence for hump-shaped relationships, and negative ones were limited to cultural services that value rarity. Given the magnitude of abundance declines among many previously common species, it is likely that there have been substantial losses of ecosystem services, providing important implications for the identification of potential tipping points in relation to defaunation resilience, biodiversity conservation, and human well-being.

9.
Hum Pathol ; 75: 95-103, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29408640

RESUMEN

The Renal Pathology Society proposed a pathological classification for diabetic nephropathy (DN) (RPS 2010). We retrospectively examined the renal structural-functional relationships using the RPS 2010 classification in 49 DN cases. We also evaluated the importance of the percentage of glomeruli with nodular diabetic glomerulosclerosis and their morphological characteristics (cellular, cellular and extracellular matrix [ECM] or ECM types) in the pathology of DN. The classes of DN (RPS 2010) were significantly correlated with the duration of diabetes mellitus (DM), degree of proteinuria, a decreased estimated glomerular filtration rate (eGFR), and the stages of Japanese clinical DM and chronic kidney disease (CKD). When the percentage of glomeruli with nodular glomerulosclerosis (IIIA <25%, IIIB 25-50%, IIIC 50-75%, and IIID >75%) was added to class III in this classification, the classes of DN had a greater correlation with the levels of proteinuria. The morphological characteristics of nodular glomerulosclerosis such as cellular, cellular and ECM, or ECM type were associated with several clinical parameters including the duration of DM, degree of proteinuria, a decreased eGFR, and/or the stages of clinical DM and CKD. Mesangial red blood cell fragments that is indicative of microvascular injury was found in cellular or cellular and ECM types of nodular glomerulosclerosis. The RPS 2010 classification is useful as a DN pathological classification that indicates a good correlation with the clinical characteristics of DN. In addition, the frequency and morphological characteristics of nodular diabetic glomerulosclerosis is important for the evaluation of the pathology in DN.


Asunto(s)
Nefropatías Diabéticas/clasificación , Nefropatías Diabéticas/patología , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
10.
Interdisciplinaria ; 34(2): 235-257, dic. 2017. ilus, tab
Artículo en Español | LILACS | ID: biblio-975772

RESUMEN

Se realizó una investigación que tuvo como objetivo establecer las relaciones funcionales entre salud mental y capital social personas que han sido víctimas del desplazamiento forzado en el marco del conflicto armado y personas en condición de pobreza. El estudio fue de tipo ex pos facto retrospectivo y participaron 380 adultos, clasificados en dos grupos: 190 en situación de desplazamiento y 190 en situación de pobreza. Se administraron los siguientes instrumentos: la Adaptación Española de las Escalas de Bienestar Psicológico de Ryff (Díaz, Rodríguez-Carvajal, Blanco, Moreno-Jiménez, Gallardo, Valle & Van Dierendonk, 2006), la Escala de Satisfacción con la Vida (Diener, 1994), la Escala de Bienestar Social (Keyes, 1998) y el Barómetro del Capital Social (Sudarsky, 1999). Posteriormente, se realizó un análisis con el software SPSS 18 para establecer las correlaciones y relaciones funcionales de las variables en los grupos de estudio. Los hallazgos dan cuenta de las correlaciones significativas entre las dimensiones constitutivas del capital social y la salud mental. En segunda instancia se presentan las relaciones funcionales, implementando los modelos de ecuaciones estructurales en cada grupo, asumiendo una relación funcional positiva entre el capital social y la salud mental, que se mantiene en cada grupo estudiado, siendo superior en el grupo de desplaza-os (β = .56) en comparación con el grupo de pobreza (β = .41). Estos hallazgos permiten evidenciar que las relaciones funcionales analizadas estructuralmente entre capital social y salud mental son directamente proporcionales y constituyen un insumo para el desarrollo de programas de intervención psicosocial orientados a la mejoría de la calidad de vida y el empoderamiento social comunitario.


This paper informs an investigation which had as objective to establish the functional relationships between mental health and social capital in people who have been victims of forced displacement in the context of the armed conflict, and people in poverty conditions. The social capital is understood from the proposal of Putnam (1993), such as the commitment that occurs between actors and social groups where there are networks and standards that facilitate collaboration, the commitment and confidence; through which you can set changes. For the present study, account is taken of the observable variables, measures through the Barometer of Social Capital developed by Sudarsky (2007) and worked in the third measurement of social capital in 2011, in the report presented by Hurtado, García, and Copete (2013), which gives an account of three factors: Solidarity, consolidation of groups and the construction of social fabric (Ksocial), institutional trust and social control (Confie) and credibility in sources of non-validated information (Fenoval). Mental health in research responds to the model of the entire state of health proposed by Keyes (2005b), which assumes the understanding of mental health as a state of well-being, more than the absence of disease, composed of three factors that for terms of the study are the observable variables that make part of the latent variable of mental health, these are: Spanish Adaptation of the Scales of Psychological Well-being of Ryff (Díaz, Rodríguez-Carvajal, Blanco, Moreno-Jiménez, Gallardo,Valle & Van Dierendonk, 2006) which focuses on the personal development, by which envisaged dimensions like the autoaceptación, positive relationships, autonomy, the domain of the environment, the personal growth and the project of life (Blanco & Valera, 2007); the Subjective Well-being (Diener, 1984), constitutes the cognitive and affective evaluations that a person generates around to his life and converges the aspects of the satisfaction and the positive emotions-negative (Blanco & Valera, 2007) and Social Welfare (Keyes, 1998), understood as the value that we of the circumstances and the operation that we have within the society. Includes items such as integration, acceptance, the contribution, the update and the social coherence. The study was retrospective exposfact type and counted 380 adults, classified in two groups: 190 in situation of displacement and 190 in situation of poverty. The instruments were the Scales Psychological Well-being (Ryff, 1989); Satisfaction with Life (Diener,1994); Social Welfare (Keyes, 1998), and the Barometer of Social Capital (Sudarsky, 1999). Subsequently, an analysis was carried out with the SPSS software 18 to establish correlations and functional relationships of the variables in the study groups. The findings give account of the significant correlations between the constituent dimensions of social capital and mental health. In second instance presents the functional relationships implementing structural equation models in each group, assuming a positive functional relationship between social capital and mental health, which is maintained in each of the groups of study, being higher in the group of displaced persons (β = .56) in comparison with the group of poverty (β = .41). These findings allowed to demonstrate that the functional relationships analyzed structurally between social capital and mental health are directly proportional and constitute an input to the development of psychosocial intervention programs aimed at the improvement of the quality of life and social empowerment community. This research is a systematic input of structural analysis of the functional relationships between Social Capital and Mental Health, to strengthen the horizon of future studies that should be directed to deepen the analysis of the complex reality that people live in a situation of vulnerability, such as is the case of those who have experienced the forced displacement by effect of the armed conflict and those who have lived in poverty.

11.
ACS Comb Sci ; 17(4): 224-33, 2015 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-25706328

RESUMEN

High-throughput experimental methodologies are capable of synthesizing, screening and characterizing vast arrays of combinatorial material libraries at a very rapid rate. These methodologies strategically employ tiered screening wherein the number of compositions screened decreases as the complexity, and very often the scientific information obtained from a screening experiment, increases. The algorithm used for down-selection of samples from higher throughput screening experiment to a lower throughput screening experiment is vital in achieving information-rich experimental materials genomes. The fundamental science of material discovery lies in the establishment of composition-structure-property relationships, motivating the development of advanced down-selection algorithms which consider the information value of the selected compositions, as opposed to simply selecting the best performing compositions from a high throughput experiment. Identification of property fields (composition regions with distinct composition-property relationships) in high throughput data enables down-selection algorithms to employ advanced selection strategies, such as the selection of representative compositions from each field or selection of compositions that span the composition space of the highest performing field. Such strategies would greatly enhance the generation of data-driven discoveries. We introduce an informatics-based clustering of composition-property functional relationships using a combination of information theory and multitree genetic programming concepts for identification of property fields in a composition library. We demonstrate our approach using a complex synthetic composition-property map for a 5 at. % step ternary library consisting of four distinct property fields and finally explore the application of this methodology for capturing relationships between composition and catalytic activity for the oxygen evolution reaction for 5429 catalyst compositions in a (Ni-Fe-Co-Ce)Ox library.


Asunto(s)
Técnicas Químicas Combinatorias , Genoma , Teoría de la Información , Ensayo de Materiales/métodos , Algoritmos , Análisis por Conglomerados
12.
Clin Ther ; 36(10): 1349-55, 2014 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-25444564

RESUMEN

PURPOSE: Articles in peer-reviewed journals and the trade press presuppose that strategic outsourcing relationships have been formed to replace preexisting collaborative approaches with contract research organizations. They do not consider that large, fragmented pharmaceutical and biotechnology companies may be supporting competing and conflicting relationship models simultaneously. A recent Tufts Center for the Study of Drug Development study quantifies actual strategic outsourcing practices among drug development companies and sheds new light on why these relationships may be failing. METHODS: Tufts Center for the Study of Drug Development conducted an in-depth assessment of 43 Phase II and III clinical studies completed since 2012 to examine the outsourcing relationships used by 9 major pharmaceutical and biotechnology companies to support key functional areas. Descriptive statistics were assessed and t tests were performed to characterize outsourcing practices by function and to determine differences in study performance between transactional and strategic outsourcing relationships. FINDINGS: The results indicate that sponsor companies are using a variety of outsourcing relationship models to support their studies, mixing and matching the use of internal staff, and using traditional transactional and strategic outsourcing relationships simultaneously. Specifically, despite the fact that each sponsor company had entered into several strategic outsourcing relationships, in no instance did a single contract research organization manage all functional areas supporting an individual Phase II or III study. In addition, sponsor companies vary the types of outsourcing relationship models that they use on a study-by-study basis. IMPLICATIONS: The inability of pharmaceutical and biotechnology companies to consistently embrace and coordinate sourcing strategies is creating internal friction and inefficiency. As a result, the expected impact of strategic outsourcing relationships on drug development performance, quality, and cost remains elusive.


Asunto(s)
Biotecnología/organización & administración , Industria Farmacéutica/organización & administración , Eficiencia Organizacional , Servicios Externos , Ensayos Clínicos Fase II como Asunto , Ensayos Clínicos Fase III como Asunto , Conducta Cooperativa , Humanos
13.
Front Physiol ; 1: 21, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21423363

RESUMEN

Aging is accompanied by considerable heterogeneity with possible co-expression of differentiation pathways. The present study investigates the interplay between crucial myogenic, adipogenic, and Wnt-related genes orchestrating aged myogenic progenitor differentiation (AMPD) using clonal gene expression profiling in conjunction with Bayesian structure learning (BSL) techniques. The expression of three myogenic regulatory factor genes (Myogenin, Myf-5, MyoD1), four genes involved in regulating adipogenic potential (C/EBPα, DDIT3, FoxC2, PPARγ), and two genes in the Wnt signaling pathway (Lrp5, Wnt5a) known to influence both differentiation programs were determined across 34 clones by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). Three control genes were used for normalization of the clonal expression data (18S, GAPDH, and B2M). Constraint-based BSL techniques, namely (a) PC Algorithm, (b) Grow-shrink (GS) algorithm, and (c) Incremental Association Markov Blanket (IAMB) were used to model the functional relationships (FRs) in the form of acyclic networks from the clonal expression profiles. A novel resampling approach that obviates the need for a user-defined confidence threshold is proposed to identify statistically significant FRs at small sample sizes. Interestingly, the resulting acyclic network consisted of FRs corresponding to myogenic, adipogenic, Wnt-related genes and their interaction. A significant number of these FRs were robust to normalization across the three house-keeping genes and the choice of the BSL technique. The results presented elucidate the delicate balance between differentiation pathways (i.e., myogenic as well as adipogenic) and possible cross-talk between pathways in AMPD.

14.
Biom J ; 25(2): 207-211, 1983.
Artículo en Inglés | MEDLINE | ID: mdl-31466426

RESUMEN

Given the normal multivariate linear regression model Y = BX + E, with B subjected to the linear restrictions H BJ = W A, J known, W and H unknown, A known, the maximum likelihood estimates of H, B, W, are obtained. A likelihood ratio test criterion for testing H = H0 , W = W0 is provided. The results are extended to the GMANOVA model. All results are obtained in terms of the original variates directly, unlike Healy (1980) who obtains the results for the MANOVA model in terms of the canonical transformations of the original variates.

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