189 research outputs found
Estudio comparativo de las características físicas del semen de ovino en el laboratorio de reproducción asistida de la Diputación de Córdoba
En el presente trabajo se ha realizado un estudio comparativo
de las caracteristicas físicas (volumen y concentración)
de semen procedente de las extracciones realizadas
en el laboratorio de Reproducción Asistida de
Pequeños Rumiantes (código comunitario ES-04-02-0C),
ubicado en el Centro Agropecuario Provincial de la
Diputación de Córdoba, durante los años 2003, 2004 y 2005. Estos trabajos se vienen desarrollando en el seno de los convenios de colaboración suscritos entre la institución cordobesa y las Asociaciones de Criadores de
Ovinos Precoces, Merino y Lacaune, para la mejora genética
de los rebaños de la provincia mediante el empleo de técnicas de inseminación artificial como medida de apoyo al desarrollo de los esquemas de selección de estas
razas. Se realizó un análisis de varianza para la evaluación
de la influencia de los efectos del año de extracción,
la raza, la época de extracción y la interacción entre la
raza y la época de extracción sobre el volumen y la concentración
seminal
New challenges in microalgae biotechnology
Photosynthetic protists, also called microalgae, have been systematically studied for more than a century. However, only recently broad biotechnological applications have fostered a novel wave of research on their potentialities as sustainable resources of renewable energy as well as valuable industrial and agro-food products. At the recent VII European Congress of Protistology held in Seville, three outstanding examples of different research strategies on microalgae with biotechnological implications were presented, which suggested that integrative approaches will produce very significant advances in this field in the next future. In any case, intense research and the application of systems biology and genetic engineering techniques are absolutely essential to reach the full potential of microalgae as cell-factories of bio-based products and, therefore, could contribute significantly to solve the problems of biosustainability and energy shortage
A data mining approach using cortical thickness for diagnosis and characterization of essential tremor.
Essential tremor (ET) is one of the most prevalent movement disorders. Being that it is a common
disorder, its diagnosis is considered routine. However, misdiagnoses may occur regularly. Over the
past decade, several studies have identified brain morphometric changes in ET, but these changes
remain poorly understood. Here, we tested the informativeness of measuring cortical thickness for
the purposes of ET diagnosis, applying feature selection and machine learning methods to a study
sample of 18 patients with ET and 18 age- and sex-matched healthy control subjects. We found that
cortical thickness features alone distinguished the two, ET from controls, with 81% diagnostic accuracy.
More specifically, roughness (i.e., the standard deviation of cortical thickness) of the right inferior
parietal and right fusiform areas was shown to play a key role in ET characterization. Moreover, these
features allowed us to identify subgroups of ET patients as well as healthy subjects at risk for ET. Since
treatment of tremors is disease specific, accurate and early diagnosis plays an important role in tremor
management. Supporting the clinical diagnosis with novel computer approaches based on the objective
evaluation of neuroimage data, like the one presented here, may represent a significant step in this
direction.post-print1720 K
A data mining approach for classification of orthostatic and essential tremor based on MRI‐derived brain volume and cortical thickness
[Abstract] Objective - Orthostatic tremor (OT) is an extremely rare, misdiagnosed, and underdiagnosed disorder affecting adults in midlife. There is debate as to whether it is a different condition or a variant of essential tremor (ET), or even, if both conditions coexist. Our objective was to use data mining classification methods, using magnetic resonance imaging (MRI)‐derived brain volume and cortical thickness data, to identify morphometric measures that help to discriminate OT patients from those with ET. Methods - MRI‐derived brain volume and cortical thickness were obtained from 14 OT patients and 15 age‐, sex‐, and education‐matched ET patients. Feature selection and machine learning methods were subsequently applied. Results - Four MRI features alone distinguished the two, OT from ET, with 100% diagnostic accuracy. More specifically, left thalamus proper volume (normalized by the total intracranial volume), right superior parietal volume, right superior parietal thickness, and right inferior parietal roughness (i.e., the standard deviation of cortical thickness) were shown to play a key role in OT and ET characterization. Finally, the left caudal anterior cingulate thickness and the left caudal middle frontal roughness allowed us to separate with 100% diagnostic accuracy subgroups of OT patients (primary and those with mild parkinsonian signs). Conclusions - A data mining approach applied to MRI‐derived brain volume and cortical thickness data may differentiate between these two types of tremor with an accuracy of 100%. Our results suggest that OT and ET are distinct conditions.National Institutes of Health (United States); #R01, NS39422National Institutes of Health (United States), #R01, NS094607National Institutes of Health (United States); #R01, NS085136National Institutes of Health (United States); #R01, NS073872National Institutes of Health (United States); #R01, NS085136National Institutes of Health (United States); #R01, NS088257European Commission; ICT‐2011‐287739Ministerio de Economía y Competitividad; RTC‐2015‐3967‐1Agencia Española de Investigación de la Salud; FIS PI12/01602Agencia Española de Investigación de la Salud; FIS PI16/00451Madrid Robotics Digital Innovation Hub; S2018/NMT‐433
Tremor severity in Parkinson’s disease and cortical changes of areas controlling movement sequencing: a preliminary study.
. There remains much to learn about the changes in cortical anatomy that are associated with tremor severity in Parkinson’s disease (PD). For this reason, we used a combination of structural neuroimaging to measure cortical thickness and neurophysiological studies to analyze whether PD tremor was associated with cortex integrity. Magnetic resonance imaging and neurophysiological assessment were performed in 13 nondemented PD patients (9 women, 69.2%) with a clearly tremor-dominant phenotype. Cortical reconstruction and volumetric segmentation was performed with the Freesurfer image analysis software. Assessment of tremor was performed by means of high-density surface electromyography (hdEMG) and inertial measurement units (IMUs). Individual motor unit discharge patterns were identified from surface hdEMG and tremor metrics quantifying motor unit synchronization from IMUs were defined. Increased motor unit synchronization (i.e., more severe tremor) was associated with cortical changes (i.e., atrophy) in dorsal premotor cortices, left posterior parietal cortex, left lateral orbitofrontal cortex, cingulate cortex bilaterally, left posterior and transverse temporal cortex, and left occipital lobe, as well as reduced left middle temporal volume. Given that the majority of these areas are involved in controlling movement sequencing, our results support Albert’s classic hypothesis that PD tremor may be the result of an involuntary activation of a program of motor behavior used in the genesis of rapid voluntary alternating movements.pre-print670 K
Indicaciones Límite de las Fracturas de Húmero con Clavo Endomedular Cerrojado
El tratamiento de las fracturas diafisarias del húmero ha entrado en controversia
en los últimos años, como lo refleja la literatura internacional. La problemática
aumenta cuando se trata de fracturas diafisarias límites que alcanzan la zona metafisaria
superior e inferior. En un intento de mejora terapéutica este grupo de autores ha testado un
clavo cerrojado para el húmero diseñado por Seidel. El promedio de seguimiento ha sido de
12 meses con un mínimo de 6 meses. El número de casos evaluados ha sido 6. Siguiendo la
cotación de Stewart, 4 de los seis pacientes obtuvieron resultados buenos o excelentes. Todos
los pacientes consolidaron sus fracturas en un período de tiempo normal, entre 3 y 5 meses,
con una media de 4 meses, 4 de los seis pacientes no se inmovilizaron con yeso en ningún momento.
La bondad y sencillez del método hace augurar buenos resultados en otros grupos ampliando
sus indicaciones.Treatment of dyaphyseal fractures of the humerus has been the
source of considerable controversy in recent years. The problem increases in
dimension when one is dealing with limiting diaphyseal fractures that invole the
upper and lower metaphyseal zone. In an attempt to improve the therapy of this
circunstance, the members of this research team have tested a locking nail for the
humerus designed by Seidel. The mean follow-up time has been 12 months, with a
minimum of six months. The number of cases evaluated was 6. According to the
scale of Stewart, four of the cases obtained good or excellent results. All the patients
consolidated their fractures within a normal period of time -between 3 and 5
months-, with a mean of 4 months. Four of the 6 patients wer e not immobilized with
paster at any time. The goodness and simplicity of the method are suggestive of
promising results in other groups by broadening its indications
Black hole masses and starbursts in X-shaped radio sources
It has been suggested that the X-shaped morphology observed in some radio
sources can reflect either a recent merger of two supermassive black holes
(SMBHs) or the presence of a second active black hole in the galactic nucleus.
These scenarios are tested by studying the relationship between the black hole
mass, radio and optical luminosity, starburst history, and dynamic age of radio
lobes in a sample of 29 X-shaped radio galaxies drawn from a list of 100
X-shaped radio source candidates identified from the FIRST survey. The same
relationships are also studied in a control sample consisting of 36 radio-loud
active nuclei with similar redshifts and optical and radio luminosities. The
X-shaped objects are found to have statistically higher black hole masses and
older starburst activity compared to the objects from the control sample.
Implications of these findings are discussed for the black hole merger scenario
and for the potential presence of active secondary black holes in post-merger
galaxies.Comment: 11 pages, 8 figure
Targeting of CTCF to the nucleolus inhibits nucleolar transcription through a poly(ADP-ribosyl)ation-dependent mechanism
Multiple functions have been reported for the transcription factor and candidate tumour suppressor, CTCF. Among others, they include regulation of cell growth, differentiation and apoptosis, enhancer-blocking activity and control of imprinted genes. CTCF is usually localized in the nucleus and its subcellular distribution during the cell cycle is dynamic; CTCF was found associated with mitotic chromosomes and the midbody, suggesting different roles for CTCF at different stages of the cell cycle. Here we report the nucleolar localization of CTCF in several experimental model systems. Translocation of CTCF from nucleoplasm to the nucleolus was observed after differentiation of K562 myeloid cells and induction of apoptosis in MCF7 breast cancer cells. CTCF was also found in the nucleoli in terminally differentiated rat trigeminal ganglion neurons. Thus our data show that nucleolar localization of CTCF is associated with growth arrest. Interestingly, the 180 kDa poly(ADP-ribosyl)ated isoform of CTCF was predominantly found in the nucleoli fractions. By transfecting different CTCF deletion constructs into cell lines of different origin we demonstrate that the central zinc-finger domain of CTCF is the region responsible for nucleolar targeting. Analysis of subnucleolar localization of CTCF revealed that it is distributed homogeneously in both dense fibrillar and granular components of the nucleolus, but is not associated with fibrillar centres. RNA polymerase I transcription and protein synthesis were required to sustain nucleolar localization of CTCF. Notably, the labelling of active transcription sites by in situ run-on assays demonstrated that CTCF inhibits nucleolar transcription through a poly(ADP-ribosyl)ation-dependent mechanism
Excitotoxic inactivation of constitutive oxidative stress detoxification pathway in neurons can be rescued by PKD1
Excitotoxicity, a critical process in neurodegeneration, induces oxidative stress and neuronal death through mechanisms largely unknown. Since oxidative stress activates protein kinase D1 (PKD1) in tumor cells, we investigated the effect of excitotoxicity on neuronal PKD1 activity. Unexpectedly, we find that excitotoxicity provokes an early inactivation of PKD1 through a dephosphorylation-dependent mechanism mediated by protein phosphatase-1 (PP1) and dual specificity phosphatase-1 (DUSP1). This step turns off the IKK/NF-κB/SOD2 antioxidant pathway. Neuronal PKD1 inactivation by pharmacological inhibition or lentiviral silencing in vitro, or by genetic inactivation in neurons in vivo, strongly enhances excitotoxic neuronal death. In contrast, expression of an active dephosphorylation-resistant PKD1 mutant potentiates the IKK/NF-κB/SOD2 oxidative stress detoxification pathway and confers neuroprotection from in vitro and in vivo excitotoxicity. Our results indicate that PKD1 inactivation underlies excitotoxicity-induced neuronal death and suggest that PKD1 inactivation may be critical for the accumulation of oxidation-induced neuronal damage during aging and in neurodegenerative disorders
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