171 research outputs found
Comparative investigations on soluble proteins and malate dehydrogenase of four grape varieties by isoelectric focusinq
Soluble proteins and multiple forms of malate dehydrogenase (E.C. 1.1.1.37) in both skin and juice of four grape varieties, have been compared with respect to heterogeneity and isoelectric point. The protein preparations resolved into 17 to 28 very distinct components. Seven (skins) and eight (juices) of these components were of common occurrence with all varieties, as judged by the same pI value. The presence of two to seven peculiar bands in both parts of berry was also observed. In the grape the NAD-malate dehydrogenase activity was associated with 9 to 13 isoelectric forms, apparently assembled into three sets of isoenzymes. Each of these showed a rather similar dislocation in the gels; but they contained a different number of isoenzymes of distinct pI value in the skin as well as in the juice of different varieties. A higher number of variant forms was found in the skins in comparison with juices. Between two and four isomalate dehydrogenases of the same net charge were found in both parts of berries of the same variety, whereas the remaining isoenzymes appeared to be non-identical and, thus, presumably the product of distinct genes.Vergleichende Untersuchung über die löslichen Proteine und die Malat-Dehydrogenasevon vier Rebsorten mittels isoelektrischer FokussierungDie löslichen Proteine und multiplen Formen der Malat-Dehydrogenase (E.C. 1.1.1.37) sowohl in der Schale als auch im Saft der Beeren von vier Rebsorten wurden in bezug auf Heterogenität und isoelektrischen Punkt verglichen. Die Proteinpräparate ließen sich in 17 bis 28 deutlich unterscheidbare Komponenten auftrennen. Aufgrund übereinstimmender pI-Werte besaßen alle Sorten in der Schale sieben und im Saft acht gleiche Komponenten. Auch wurden in den beiden Teilen der Beere zwei bis sieben charakteristische Proteinbanden beobachtet.Das Muster der NAD-Malat-Dehydrogenase in der Beere setzt sich aus 9 bis 13 isoelektrischen Formen zusammen, die offensichtlich in drei Gruppen von Isoenzymen angeordnet sind. Die einzelnen Gruppen waren in den Gelen ziemlich übereinstimmend lokalisiert; aber die einzelnen Sorten besaßen sowohl in der Schale als auch im Saft eine unterschiedliche Anzahl von Enzymen eines bestimmten pI-Wertes. In den Schalen wurde eine vergleichsweise größere Anzahl unterschiedlicher Isoenzyme gefunden als in den Säften. In den beiden Beerenteilen einer Sorte wurden zwei bis vier Isomalat-Dehydrogenasen mit übereinstimmendem pI-Wert ermittelt, während die restlichen Isoenzyme anscheinend nicht identisch und somit wohl auf ungleiche Gene zurückzuführen waren
Nanoscale intermittent contact-scanning electrochemical microscopy
A major theme in scanning electrochemical microscopy (SECM) is a methodology for nanoscale imaging with distance control and positional feedback of the tip. We report the expansion of intermittent contact (IC)-SECM to the nanoscale, using disk-type Pt nanoelectrodes prepared using the laser-puller sealing method. The Pt was exposed using a focused ion beam milling procedure to cut the end of the electrode to a well-defined glass sheath radius, which could also be used to reshape the tips to reduce the size of the glass sheath. This produced nanoelectrodes that were slightly recessed, which was optimal for IC-SECM on the nanoscale, as it served to protect the active part of the tip. A combination of finite element method simulations, steady-state voltammetry and scanning electron microscopy for the measurement of critical dimensions, was used to estimate Pt recession depth. With this knowledge, the tip-substrate alignment could be further estimated by tip approach curve measurements. IC-SECM has been implemented by using a piezo-bender actuator for the detection of damping of the oscillation amplitude of the tip, when IC occurs, which was used as a tip-position feedback mechanism. The piezo-bender actuator improves significantly on the performance of our previous setup for IC-SECM, as the force acting on the sample due to the tip is greatly reduced, allowing studies with more delicate tips. The capability of IC-SECM is illustrated with studies of a model electrode (metal/glass) substrate
Verso una "cultura" del disinvestimento: Efficienza, Superiorit\ue0 e Conformit\ue0
Strategic management research has always been committed to portray divestitures just as a reaction to
strategic mistakes or a change to earlier decisions. Yet, scholars have recently gauged that divestiture
operations represent a keystone in firm value creation (e.g. Moschieri and Mair, 2011) propelling change
process. This article reviews existing research on divestiture classifying it into three schools of thought - firm
efficiency, firm superiority and firm conformity \u2013 based on different assumptions and conceptualizations of
firms and firm objectives. Moreover, it introduces a taxonomy of divestiture operations that accounts for
their heterogeneous determinants, thus proposing to read divestiture no longer and not only as a sign of
failure, but rather as a tool to create and preserve shareholders\u2019 wealth
Multi-aspect testing and ranking inference to quantify dimorphism in the cytoarchitecture of cerebellum of male, female and intersex individuals: a model applied to bovine brains.
The dimorphism among male, female and freemartin intersex bovines, focusing on the vermal lobules VIII and IX, was analyzed using a novel data analytics approach to quantify morphometric differences in the cytoarchitecture of digitalized sections of the cerebellum. This methodology consists of multivariate and multi-aspect testing for cytoarchitecture-ranking, based on neuronal cell complexity among populations defined by factors, such as sex, age or pathology. In this context, we computed a set of shape descriptors of the neural cell morphology, categorized them into three domains named size, regularity and density, respectively. The output and results of our methodology are multivariate in nature, allowing an in-depth analysis of the cytoarchitectonic organization and morphology of cells. Interestingly, the Purkinje neurons and the underlying granule cells revealed the same morphological pattern: female possessed larger, denser and more irregular neurons than males. In the Freemartin, Purkinje neurons showed an intermediate setting between males and females, while the granule cells were the largest, most regular and dense. This methodology could be a powerful instrument to carry out morphometric analysis providing robust bases for objective tissue screening, especially in the field of neurodegenerative pathologies
Mr-Nom: Multi-Scale Resolution of Neuronal Cells in Nissl-Stained Histological Slices Via Deliberate over-Segmentation and Merging
In comparative neuroanatomy, the characterization of brain cytoarchitecture is critical to a better understanding of brain structure and function, as it helps to distill information on the development, evolution, and distinctive features of different populations. The automatic segmentation of individual brain cells is a primary prerequisite and yet remains challenging. A new method (MR-NOM) was developed for the instance segmentation of cells in Nissl-stained histological images of the brain. MR-NOM exploits a multi-scale approach to deliberately over-segment the cells into superpixels and subsequently merge them via a classifier based on shape, structure, and intensity features. The method was tested on images of the cerebral cortex, proving successful in dealing with cells of varying characteristics that partially touch or overlap, showing better performance than two state-of-the-art methods
Enfermedad de pompe: presentación de un caso
Presentamos el caso de una niña de 6 meses de ascendencia china con enfermedad de Pompe diagnosticada a partir de una miocardiopatía hipertrófica biventricular e hipotonía global.
En esta enfermedad el acúmulo de glucógeno lisosomal principalmente en el corazón y músculo esquelético ocasiona la mayoría de la sintomatología clínica. En esta paciente la hipotonía generalizada, macroglosia, debilidad en el llanto y la confirmación ecocardiográfica de una miocardiopatía hipertrófica biventricular fueron el punto inicial para la sospecha clínica de la enfermedad que, junto a la elevación de enzimas musculares y hepáticas, condujo al estudio de alfa-glucosidasa ácida (AGA) que confirmó el diagnóstico. Desde 2006 existe terapia de reemplazo enzimático que permite mejorar la sobrevida y la calidad de vida si el diagnóstico se realiza precozmente.We are presenting the case of a 7 month old infant with infantile Pompe disease, who was the first case treated by enzyme replacement therapy (ERT) at our Hospital.The patient was of chinese ancestry and was suspected to have the disease after finding biventricular hypertrophic myocardiopathy and muscle weakness and hypotonia. Other relevant features were macroglosia and increase in CK level as well as the results of the electrophysiology studies. In view of the new possibility of ERT, educational efforts must be done in order to perform early diagnosis before signs of severe cardiorespiratory failure develops, and to improve survival and quality of life of patients with this condition
Attività e forme molecolari multiple di α-amilasi, α-glucosidasi e invertasi dell'uva in maturazione
A partire dall' invaiatura fino alla completa maturazione dell' uva Tocai sono stati seguiti i cambiamenti relativi alle forme multiple e alle attività specifiche di invertasi, a-amilasi e a-glucosidasi. All' invai.altura l'invertasi è presente con tre varianti isoenzimatiche, una delle quali scompare subito dopo. Tale scomparsa si verifica in concomitanza con la rapida diminuzione dell' attività dell' enzima e col simultaneo consistente aumento nell' acino del contenuto in zucchero riducenti. Per l' α-amilasi e l' α-glucosidasi i cambiamenti che intervengono nei loro patterns isoenzimatici non si sono dimostrati strettamente correlati con le variazioni delle loro attività specifiche. Le curve di attività di entrambi gli enzimi hanno dimostrato un andamento piuttosto parallelo e un massimo a sei settimane dall'invaiatura. I livelli di attività di a-amilasi s quelli di a-glucosidasi sono discussi con riferimento ai dati esistenti in letteratura sul contenuto d'amido nella uva.Activities and multiple molecular forms of α-amylase, α-glucosidase and invertaseduring ripening of grape berriesChanges in multiple forms and specific activities of invertase, α-amylase and α-glucosidase were followed during the ripening of Tokay grape berries. Different ripening stages of grape were accompanied by variations in the number of isoenzyme bands as well as in the level of activity of the enzymes examined. The activity levels of both α-amylase and α-glucosidase are discussed in relation to the literature data on starch content in grape
Multi-aspect testing and ranking inference to quantify dimorphism in the cytoarchitecture of cerebellum of male, female and intersex individuals: a model applied to bovine brains
The dimorphism among male, female and freemartin intersex bovines, focusing on the vermal lobules VIII and IX, was analyzed using a novel data analytics approach to quantify morphometric differences in the cytoarchitecture of digitalized sections of the cerebellum. This methodology consists of multivariate and multi-aspect testing for cytoarchitecture-ranking, based on neuronal cell complexity among populations defined by factors, such as sex, age or pathology. In this context, we computed a set of shape descriptors of the neural cell morphology, categorized them into three domains named size, regularity and density, respectively. The output and results of our methodology are multivariate in nature, allowing an in-depth analysis of the cytoarchitectonic organization and morphology of cells. Interestingly, the Purkinje neurons and the underlying granule cells revealed the same morphological pattern: female possessed larger, denser and more irregular neurons than males. In the Freemartin, Purkinje neurons showed an intermediate setting between males and females, while the granule cells were the largest, most regular and dense. This methodology could be a powerful instrument to carry out morphometric analysis providing robust bases for objective tissue screening, especially in the field of neurodegenerative pathologies
The motor cortex of the sheep: laminar organization, projections and diffusion tensor imaging of the intracranial pyramidal and extrapyramidal tracts
The laminar organization of the motor cortex of the sheep and other large domestic herbivores received scarce attention and is generally considered homologous to that of rodents and primates. Thickness of the cortex, subdivision into layers and organization are scarcely known. In the present study, we applied different modern morphological, mathematical and image-analyses techniques to the study of the motor area that controls movements of the forelimb in the sheep. The thickness of the cortex resulted comparable to that of other terrestrial Cetartiodactyls (but thicker than in marine Cetartiodactyls of similar body mass). The laminar organization showed marked development of layer 1, virtual absence of layer 4, and image analysis suggested prevalence of large irregular neural cells in the deeper layers. Diffusion tensor imaging revealed robust projections from the motor cortex to the pyramids in the brainstem, and well evident tracts descending to the tegmentum of the mesencephalon and dorsal pons. Our data contrast the general representation of the motor system of this species, considered to be predominantly based on extra-pyramidal tracts that originate from central pattern generators in the brainstem. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature
Influenza della cicloeximide, della DL-etionina, della L-andrenalina e del cortisolo sulla biosintesi della glicerina e dell'acetoina da parte di Kloeckera apiculata
Nella fermentazione alcolica del mosto d'uva con Kl. apiculata, la cicloeximide (acticlione) inibiva parzialmente la formazione della glicerina e clell'acetoina. L'inibizione della formazione della glicerina era parzialmente contrastata dalla L-adrenalina, mentre la DL-etionina e il cortisolo contrastavano quella dell'acetoina. La cicloeximide causava anche un aumento del rendimento in alcole. L'etionina attivava tanto la formazione della glicerina quanto quella dell'acetoina. L'adrenalina non influiva sulla formazione della glicerina, ma inibiva fortemente quella dell'acetoina. In presenza di cortisolo avveniva il contrario. I risultati sono discussi in relazione alla possibilità di variare i rapporti fra i prodotti secondari della fermentazione con l'aiuto di sostanze endogene o esogene ai mosti.Einfluß von Cycloheximid, DL-Aethionin, L-Adrenalin und Cortisol auf die von Kloeckera apiculata verursachte Biosynthese des Glycerin und des AcetoinIn der von Kloeckera apiculata verursachten alkoholischen Gärung des Traubenmostes hemmte Cycloheximid (Actidion) die Glyzerin- und Acetoinbildung teilweise. Die Hemmung der Glycerinbildung wurde zum Teil von L-Adrenalin aufgehoben, während DL-Aethionin und Cortisol der Hemmung der Acetoinbildung entgegenwirkten. Cycloheximid verursachte auch eine Zunahme der Alkoholbildung während der Gärung.Die Glyzerin- und Acetoinbildung wurde von DL-Aethionin aktiviert. L-Adrenalin übte keine Wirkung auf die Glyzerinbildung aus, hemmte jedoch die Acetoinbildung. In Anwesenheit von Cortisol erfolgte das Gegenteil.Die Ergebnisse wurden hinsichtlich der Möglichkeit erörtert, die Anteile der sekundären Gärungsprodukte mit Hilfe endogener oder exogener Stoffe zu verändern
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