2,019 research outputs found
Orientarsi nella rete, considerata quale artefatto cognitivo
La logica del Web 2.0 si basa sulla condivisione, partecipazione e interattività , portando l’esperienza di Internet e del suo uso, fino ad integrare e riprodurre schemi analoghi a quelli riscontrabili nelle Reti Sociali reali. A questo punto, sorgono alcune domande: in che modo il Web 2.0 viene utilizzato per la raccolta di informazioni che possono influenzare le scelte di studio e di vita?Si può pensare che l'utilizzo di piattaforme Web 2.0 modificare le strutture che gli psicologi chiamano meta-cognitive, in grado di modulare la costruzione, la ricerca, catalogazione e utilizzo delle informazioni? Una ricerca, ancora in corso, è stato avviata con lo scopo di rispondere a questi interrogativi, portando alla costruzione di un questionario: NETQRE 2.0, sia in versione cartacea sia in versione on-line. I primi dati sembrano indicare che l'uso di internet in generale e, in particolare per l'orientamento, è fatto in un modo passivo, senza sfruttare appieno tutti gli strumenti che caratterizzano il Web 2.
Urinary exosomal shuttle RNA: Promising cancer diagnosis biomarkers of lower urinary tract.
Background: Prostate and bladder cancers continue to be the first and fourth most common cancers in men worldwide; thus there is an urgent need for more accurate biomarkers that can detect these types of cancer in a non-invasive way. Liquid biopsy is a new non-invasive tool for diagnosis and with a virtually unlimited supply urine is even more attractive resource since urinary exosomes have been discovered to contain RNAs that are hallmarks of cancer. It is challenging to assay those secreting lower amounts of molecules. Methods: This review, based on articles identified through a PubMed/MEDLINE search, comprehensively summarizes state of the art approaches used in the discovery and validation of exosomal RNA biomarkers purified from the urine for lower urinary tract cancer. Results: The combination of PCA3 and ERG has shown a relatively good improvement in diagnostic performance; examples of other potential biomarkers and the methods utilized in their discovery are also discussed in this review. Conclusions: Of these last markers, to date there are still few data to implement these for routine diagnosis
Effect of exercise training on neuromuscular function of elbow flexors and knee extensors of type 2 diabetic patients
Purpose: The effects of exercise training on neuromuscular function of arm and leg muscles in type 2 diabetic patients (T2D) was investigated.
Methods: Eight T2D sedentary male patients (61.0 ± 2.3 years) and eight sedentary healthy age matched control subjects (H, 63.9 ± 3.8 years) underwent a 16-week supervised combined endurance and resistance exercise program. Before and after training, maximal isometric (MVIC), isokinetic (15, 30, 60, 120, 180, 240° s−1) torque and muscle endurance of the elbow flexors (EF) and knee extensors (KE) were assessed. Simultaneously, surface electromyographic signals from biceps brachii (BB) and vastus lateralis (VL) muscles were recorded and muscle fiber conduction velocity (MFCV) estimated.
Results: Following training, maximal torque of the KE increased during MVIC and isokinetic contractions at 15 and 30° s−1 in the T2D (+19.1 ± 2.7% on average; p 0.05). MFCV recorded from the VL during MVIC and during isokinetic contractions at 15 and 30° s−1 increased (+11.2 ± 1.6% on average; p < 0.01), but in the diabetic group only. Muscular endurance was lower in T2D (20.1 ± 0.7 s) compared to H (26.9 ± 1.3 s), with an associated increase in the MFCV slope after training in the KE muscles only.
Conclusion: The effect of a combined exercise training on muscle torque appears to be angular velocity-specific in diabetic individuals, with a more pronounced effect on KE muscles and at slow contraction velocities, along with an associated increase in the MFCV. MFCV appears to be a more sensitive marker than torque in detecting the early signs of neuromuscular function reconditioning
Flexible multi-beam light-sheet fluorescence microscope for live imaging without striping artifacts
The development of light-sheet fluorescence microscopy (LSFM) has greatly expanded the experimental capabilities in many biological and biomedical research fields, enabling for example live studies of murine and zebrafish neural activity or of cell growth and division. The key feature of the method is the selective illumination of a sample single plane, providing an intrinsic optical sectioning and allowing direct 2D image recording. On the other hand, this excitation scheme is more affected by absorption or scattering artifacts in comparison to point scanning methods, leading to un-even illumination. We present here an easily implementable method, based on acousto-optical deflectors (AOD), to overcome this obstacle. We report the advantages provided by flexible and fast AODs in generating simultaneous angled multiple beams from a single laser beam and in fast light sheet pivoting and we demonstrate the suppression of illumination artifacts
Whole-brain functional imaging to highlight differences between the diurnal and nocturnal neuronal activity in zebrafish larvae
Most living organisms show highly conserved physiological changes following a
24-hour cycle which goes by the name of circadian rhythm. Among experimental
models, the effects of light-dark cycle have been recently investigated in the
larval zebrafish. Owing to its small size and transparency, this vertebrate
enables optical access to the entire brain. Indeed, the combination of this
organism with light-sheet imaging grants high spatio-temporal resolution
volumetric recording of neuronal activity. This imaging technique, in its
multiphoton variant, allows functional investigations without unwanted visual
stimulation. Here, we employed a custom two-photon light-sheet microscope to
study whole-brain differences in neuronal activity between diurnal and
nocturnal periods in larval zebrafish. We describe for the first time an
activity increase in the low frequency domain of the pretectum and a
frequency-localised activity decrease of the anterior rhombencephalic turning
region during the nocturnal period. Moreover, our data confirm a nocturnal
reduction in habenular activity. Furthermore, whole-brain detrended fluctuation
analysis revealed a nocturnal decrease in the self-affinity of the neuronal
signals in parts of the dorsal thalamus and the medulla oblongata. Our data
show that whole-brain nonlinear light-sheet imaging represents a useful tool to
investigate circadian rhythm effects on neuronal activity.Comment: 18 pages, 6 figure
Effects of excitation light polarization on fluorescence emission in two-photon light-sheet microscopy
Light-sheet microscopy (LSM) is a powerful imaging technique that uses a
planar illumination oriented orthogonally to the detection axis. Two-photon
(2P) LSM is a variant of LSM that exploits the 2P absorption effect for sample
excitation. The light polarization state plays a significant, and often
overlooked, role in 2P absorption processes. The scope of this work is to test
whether using different polarization states for excitation light can affect the
detected signal levels in 2P LSM imaging of typical biological samples with a
spatially unordered dye population. Supported by a theoretical model, we
compared the fluorescence signals obtained using different polarization states
with various fluorophores (fluorescein, EGFP and GCaMP6s) and different samples
(liquid solution and fixed or living zebrafish larvae). In all conditions, in
agreement with our theoretical expectations, linear polarization oriented
parallel to the detection plane provided the largest signal levels, while
perpendicularly-oriented polarization gave low fluorescence signal with the
biological samples, but a large signal for the fluorescein solution. Finally,
circular polarization generally provided lower signal levels. These results
highlight the importance of controlling the light polarization state in 2P LSM
of biological samples. Furthermore, this characterization represents a useful
guide to choose the best light polarization state when maximization of signal
levels is needed, e.g. in high-speed 2P LSM.Comment: 16 pages, 4 figures. Version of the manuscript accepted for
publication on Biomedical Optics Expres
Who chooses alternative sources of information about childhood vaccinations? A cross-sectional study
Introduction: Vaccine hesitancy can lead to problematic outcomes in terms of public health. A factor playing a fundamental role in this dynamic is the source of information considered by parents in the decision-making progress that leads to the acceptance or refusal of childhood vaccinations. This study aims to investigate the sources of information considered by the parents of children attending primary and secondary schools in two large Italian cities and to identify predictors that led to choosing alternative sources of information.
Methods: An online questionnaire was administered to the parents of students attending elementary, middle, and high schools in Rome and Turin. Two validated tools were used: the Parent Attitudes about Childhood Vaccines Survey and the Vaccine Health Literacy of adults in Italian. Sources of information about vaccinations, trust toward the healthcare system, hesitancy and attitudes about COVID-19 vaccinations, were also investigated. A multivariable logistic regression model was built to identify predictors of the preferred sources of information on the topic.
Results: Totally, 2,301 answers to the survey were collected from June to October 2021. Of these, 1,127 came from parents in Rome (49%) and 1,174 from parents based in Turin (51%) with a mean age of 47.7 years (±6.4). The majority of the respondents were mothers (81%), married (73%), with two or more children (70.5%). The multivariable logistic regression model results showed that fathers were more inclined than mothers to use alternative sources of information (OR 1.48, 95% CI 1.29–2.00). Moreover, a higher level of vaccine hesitancy was a strong predictor for choosing alternative sources of information (OR 2.45, 95% CI 1.73–3.46). The HLVa-it scores show that parents with a lower Vaccine Literacy (VL) were more inclined to use alternative sources of information.
Discussion: Addressing health literacy issues and changing the official forms of communication could help improving vaccine acceptance. This study shows the importance of rebuilding a trusting relationship between patients and health care providers, which is fundamental in the fight against vaccine hesitancy
Fast whole-brain imaging of seizures in zebrafish larvae by two-photon light-sheet microscopy
Light-sheet fluorescence microscopy (LSFM) enables real-time whole-brain
functional imaging in zebrafish larvae. Conventional one photon LSFM can
however induce undesirable visual stimulation due to the use of visible
excitation light. The use of two-photon (2P) excitation, employing
near-infrared invisible light, provides unbiased investigation of neuronal
circuit dynamics. However, due to the low efficiency of the 2P absorption
process, the imaging speed of this technique is typically limited by the
signal-to-noise-ratio. Here, we describe a 2P LSFM setup designed for
non-invasive imaging that enables quintuplicating state-of-the-art volumetric
acquisition rate of the larval zebrafish brain (5 Hz) while keeping low the
laser intensity on the specimen. We applied our system to the study of
pharmacologically-induced acute seizures, characterizing the spatial-temporal
dynamics of pathological activity and describing for the first time the
appearance of caudo-rostral ictal waves (CRIWs).Comment: Replacement: accepted version of the manuscript, to be published in
Biomedical Optics Express. 36 pages, 15 figure
The importance of the excitation light polarization state for the optimization of the signal levels in two-photon light-sheet microscopy
Reconstruction scheme for excitatory and inhibitory dynamics with quenched disorder: application to zebrafish imaging
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