Search results for "general [Sun]"

Palliative Endoscopic Esophageal Stenting for Malignant Esophageal Tumour Complications: A Clinical Case and Single Centre Experience in Latvia

2020

Abstract Esophageal stenting is used in patients with malignant esophageal tumours to reduce dysphagia and inanition. The objective of this study was to analyse the main reasons for esophageal stenting in Rīga East Clinical University Hospital (RECUH) and their association with dysphagia and mortality. A cross-sectional study of all patients hospitalised in RECUH who received esophageal self-expanding metal stents (SEMS) from October 2013 to December 2015 was performed. A total of 29 patients, 24 (82.8%) male and 5 (17.2%) female, with mean age 63.7 ± 11.3 years, underwent the procedure. The most common indications for stenting were tumour-related stenosis (52.9%) and fistulae (17.6%). Mean…

'Palaeoshellomics' reveals the use of freshwater mother-of-pearl in prehistory

2019

The extensive use of mollusc shell as a versatile raw material is testament to its importance in prehistoric times. The consistent choice of certain species for different purposes, including the making of ornaments, is a direct representation of how humans viewed and exploited their environment. The necessary taxonomic information, however, is often impossible to obtain from objects that are small, heavily worked or degraded. Here we propose a novel biogeochemical approach to track the biological origin of prehistoric mollusc shell. We conducted an in-depth study of archaeological ornaments using microstructural, geochemical and biomolecular analyses, including ‘palaeoshellomics’, the first…

Barrel Cortex Function Special Issue Editorial

2018

TReND in Africa: Toward a Truly Global (Neuro)science Community

2020

TReND is a volunteer-scientist run charity dedicated to promoting research and education on the African continent. Focusing on neuroscience, we discuss approaches to address some of the factors that currently stifle Africa's scientific development and our experience in implementing them.

Positive Controls in Adults and Children Support That Very Few, If Any, New Neurons Are Born in the Adult Human Hippocampus.

2020

Adult hippocampal neurogenesis was originally discovered in rodents. Subsequent studies identified the adult neural stem cells and found important links between adult neurogenesis and plasticity, behavior, and disease. However, whether new neurons are produced in the human dentate gyrus (DG) during healthy aging is still debated. We and others readily observe proliferating neural progenitors in the infant hippocampus near immature cells expressing doublecortin (DCX), but the number of such cells decreases in children and few, if any, are present in adults. Recent investigations using dual antigen retrieval find many cells stained by DCX antibodies in adult human DG. This has been interprete…

Group analysis of ongoing EEG data based on fast double-coupled nonnegative tensor decomposition

2019

Abstract Background Ongoing EEG data are recorded as mixtures of stimulus-elicited EEG, spontaneous EEG and noises, which require advanced signal processing techniques for separation and analysis. Existing methods cannot simultaneously consider common and individual characteristics among/within subjects when extracting stimulus-elicited brain activities from ongoing EEG elicited by 512-s long modern tango music. New method Aiming to discover the commonly music-elicited brain activities among subjects, we provide a comprehensive framework based on fast double-coupled nonnegative tensor decomposition (FDC-NTD) algorithm. The proposed algorithm with a generalized model is capable of simultaneo…

Human hippocampal neurogenesis drops sharply in children to undetectable levels in adults.

2018

New neurons continue to be generated in the subgranular zone of the dentate gyrus of the adult mammalian hippocampus(1-5). This process has been linked to learning and memory, stress and exercise, and is thought to be altered in neurological disease(6-10). In humans, some studies have suggested that hundreds of new neurons are added to the adult dentate gyrus every day(11), whereas other studies find many fewer putative new neurons(12-14). Despite these discrepancies, it is generally believed that the adult human hippocampus continues to generate new neurons. Here we show that a defined population of progenitor cells does not coalesce in the subgranular zone during human fetal or postnatal …

Detecting differences with magnetoencephalography of somatosensory processing after tactile and electrical stimuli.

2018

Abstract Background Deviant stimuli within a standard, frequent stimulus train induce a cortical somatosensory mismatch response (SMMR). The SMMR reflects the brain’s automatic mechanism for the detection of change in a somatosensory domain. It is usually elicited by electrical stimulation, which activates nerve fibers and receptors in superficial and deep skin layers, whereas tactile stimulation is closer to natural stimulation and activates uniform fiber types. We recorded SMMRs after electrical and tactile stimuli. Method 306-channel magnetoencephalography recordings were made with 16 healthy adults under two conditions: electrical (eSMMR) and tactile (tSMMR) stimulations. The SMMR proto…

Cognitive network hyperactivation and motor cortex decline correlate with ALS prognosis.

2021

We aimed to quantitatively characterize progressive brain network disruption in Amyotrophic Lateral Sclerosis (ALS) during cognition using the mismatch negativity (MMN), an electrophysiological index of attention switching. We measured the MMN using 128-channel EEG longitudinally (2-5 timepoints) in 60 ALS patients and cross-sectionally in 62 healthy controls. Using dipole fitting and linearly constrained minimum variance beamforming we investigated cortical source activity changes over time. In ALS, the inferior frontal gyri (IFG) show significantly lower baseline activity compared to controls. The right IFG and both superior temporal gyri (STG) become progressively hyperactive longitudina…

Implicitly and explicitly assessed anxiety: No relationships with recognition of and brain response to facial emotions.

2019

Abstract Trait anxiety, the disposition to experience anxiety, is known to facilitate perception of threats. Trait anxious individuals seem to identify threatening stimuli such as fearful facial expressions more accurately, especially when presented under temporal constraints. In past studies on anxiety and emotion face recognition, only self-report or explicit measures of anxiety have been administered. Implicit measures represent indirect tests allowing to circumvent problems associated with self-report. In our study, we made use of implicit in addition to explicit measures to investigate the relationships of trait anxiety with recognition of and brain response to emotional faces. 75 heal…