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1.
Plant Divers ; 43(2): 125-133, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33997545

RESUMEN

Two varieties of Bouteloua aristidoides have been recognized, the widespread var. aristidoides and the more narrowly distributed var. arizonica. The two varieties differ in inflorescence form even more than that seen between many other closely related species of Bouteloua. We therefore asked whether these taxa might be better regarded as distinct species. A total of 93 vouchers were studied by using morphometry (principal components analysis and statistical tests), leaf micromorphology, ancestral state reconstruction, and/or molecular (ITS, trnC-rpoB and trnT-L-F) phylogenetic analyses. Except from the ITS tree, all results supported elevation of B. aristidoides var. arizonica to the rank of species, thus the new combination Bouteloua arizonica (M.E. Jones) L.F. Cuellar & Columbus comb. nov. et stat. nov., is proposed. Chloroplast and combined chloroplast-nuclear molecular trees depicted var. arizonica as monophyletic (even in sympatric populations with var. aristidoides) and reveals phylogenetic structure within var. aristidoides for which the presence of new undescribed varieties of B. aristidoides (different from B. arizonica) is addressed. B. arizonica differs from B. aristidoides in having fewer branches per inflorescence, a bigger branch with more spikelets, and a shorter branch extension. Scanning electron microscopy revealed the presence of papillae on leaves of B. arizonica as a clear synapomorphy. Growing mature plants of B. arizonica from seeds in a greenhouse revealed a strong cleistogamous nature for this species for which gene flow in sympatric populations with B. aristidoides seems unlikely. A taxonomic treatment and distribution map for identification of B. arizonica is provided.

2.
Nutr Neurosci ; 24(5): 395-405, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-31288630

RESUMEN

INTRODUCTION: The brain plays an important regulatory role in directing energy homeostasis and eating behavior. The increased ingestion of sugars and sweeteners over the last decades makes investigating the effects of these substances on the regulatory function of the brain of particular interest. We investigated whole brain functional response to the ingestion of nutrient shakes sweetened with either the nutritive natural sugars glucose and fructose, the low- nutritive natural sugar replacement allulose or the non-nutritive artificial sweetener sucralose. METHODS: Twenty healthy, normal weight, adult males underwent functional MRI on four separate visits. In a double-blind randomized study setup, participants received shakes sweetened with glucose, fructose, allulose or sucralose. Resting state functional MRI was performed before and after ingestion. Changes in Blood Oxygen Level Dependent (BOLD) signal, functional network connectivity and voxel based connectivity by Eigenvector Centrality Mapping (ECM) were measured. RESULTS: Glucose and fructose led to significant decreased BOLD signal in the cingulate cortex, insula and the basal ganglia. Glucose led to a significant increase in eigen vector centrality throughout the brain and a significant decrease in eigen vector centrality in the midbrain. Sucralose and allulose had no effect on BOLD signal or network connectivity but sucralose did lead to a significant increase in eigen vector centrality values in the cingulate cortex, central gyri and temporal lobe. DISCUSSION: Taken together our findings show that even in a shake containing fat and protein, the type of sweetener can affect brain responses and might thus affect reward and satiety responses and feeding behavior. The sweet taste without the corresponding energy content of the non-nutritive sweeteners appeared to have only small effects on the brain. Indicating that the while ingestion of nutritive sugars could have a strong effect on feeding behavior, both in a satiety aspect as well as rewarding aspects, non-nutritive sweeteners appear to not have these effects. TRIAL REGISTRATION: This study is registered at clinicaltrials.gov under number NCT02745730.


Asunto(s)
Encéfalo/efectos de los fármacos , Encéfalo/fisiología , Azúcares de la Dieta/administración & dosificación , Edulcorantes/administración & dosificación , Adolescente , Adulto , Mapeo Encefálico , Método Doble Ciego , Humanos , Imagen por Resonancia Magnética , Masculino , Vías Nerviosas/efectos de los fármacos , Vías Nerviosas/fisiología , Adulto Joven
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 184: 128-133, 2017 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-28494374

RESUMEN

The present work compares the dissimilarity and covariance based unsupervised chemometric classification approaches by taking the total synchronous fluorescence spectroscopy data sets acquired for the cumin and non-cumin based herbal preparations. The conventional decomposition method involves eigenvalue-eigenvector analysis of the covariance of the data set and finds the factors that can explain the overall major sources of variation present in the data set. The conventional approach does this irrespective of the fact that the samples belong to intrinsically different groups and hence leads to poor class separation. The present work shows that classification of such samples can be optimized by performing the eigenvalue-eigenvector decomposition on the pair-wise dissimilarity matrix.


Asunto(s)
Algoritmos , Preparaciones de Plantas/análisis , Preparaciones de Plantas/química , Espectrometría de Fluorescencia/métodos , Bases de Datos de Compuestos Químicos
4.
J Theor Biol ; 363: 188-97, 2014 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-25128737

RESUMEN

BACKGROUND: Serovars of Salmonella enterica, namely Typhi and Typhimurium, reportedly, are the bacterial pathogens causing systemic infections like gastroenteritis and typhoid fever. To elucidate the role and importance in such infection, the proteins of the Type III secretion system of Salmonella pathogenicity islands and two component signal transduction systems, have been mainly focused. However, the most indispensable of these virulent ones and their hierarchical role has not yet been studied extensively. RESULTS: We have adopted a theoretical approach to build an interactome comprising the proteins from the Salmonella pathogeneicity islands (SPI) and two component signal transduction systems. This interactome was then analyzed by using network parameters like centrality and k-core measures. An initial step to capture the fingerprint of the core network resulted in a set of proteins which are involved in the process of invasion and colonization, thereby becoming more important in the process of infection. These proteins pertained to the Inv, Org, Prg, Sip, Spa, Ssa and Sse operons along with chaperone protein SicA. Amongst them, SicA was figured out to be the most indispensable protein from different network parametric analyses. Subsequently, the gene expression levels of all these theoretically identified important proteins were confirmed by microarray data analysis. Finally, we have proposed a hierarchy of the proteins involved in the total infection process. This theoretical approach is the first of its kind to figure out potential virulence determinants encoded by SPI for therapeutic targets for enteric infection. CONCLUSIONS: A set of responsible virulent proteins was identified and the expression level of their genes was validated by using independent, published microarray data. The result was a targeted set of proteins that could serve as sensitive predictors and form the foundation for a series of trials in the wet-lab setting. Understanding these regulatory and virulent proteins would provide insight into conditions which are encountered by this intracellular enteric pathogen during the course of infection. This would further contribute in identifying novel targets for antimicrobial agents.


Asunto(s)
Sistemas de Secreción Bacterianos/genética , Islas Genómicas/fisiología , Mapeo de Interacción de Proteínas/métodos , Salmonella/metabolismo , Salmonella/patogenicidad , Transducción de Señal/fisiología , Proteínas Bacterianas/metabolismo , Redes Reguladoras de Genes/genética , Análisis por Micromatrices , Chaperonas Moleculares/metabolismo , Salmonella/genética
5.
J Tradit Complement Med ; 2(3): 164-85, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24716130

RESUMEN

The pulse examination ( mài zhen) is a unique diagnostic approach of Traditional Chinese Medicine. The description of pulse examination in the history of Traditional Chinese Medicine is full of amazement and mythology. After researching in hemodynamics and investigating in clinical application for three decades, this article describes the development and the merits and demerits of pulse examination. The experiences of the ancients are tried to be illustrated with modern knowledge and language. As the theory of resonant blood circulation is discovered, Traditional Chinese Medicine could be on the shoulder of Newton and then lead the development of modern medicine. Hope the tool of pulse examination constructed according to eigen-vector with specific time domain and position can bring the running water for Traditional Chinese Medicine. Quantitative research could overcome the plight of analog logic qualitative research, and therefore bring new health revolution.

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