Miracle-dz/UniFAR-FTUs huggingface dataset:
Evaluation of Thyrotropin Secretion Before and After TRH by Third Generation Chemiluminescent Assay

Summary The recent introduction of third generation assays for TSH has led to a considerable improvement of assay sensitivity. To assess the clinical significance of sub normal basal TSH (b-TSH) values (<0.2 uU/ml), we inves tigated b-TSH and TRH-stimulated TSH (r-TSH) by means of a new, highly sensitive immunochemiluminometric assay in 105 euthyroid subjects, 45 patients with overt hyperthy roidism and 18 patients suspected of having subclinical hy perthyroidism. A weak, albeit statistically significant, corre lation (r = 0.48) was found between b-TSH and r-TSH and also between b-TSH and 8-TSH (r = 0.31) in euthyroid sub jects. Consideration of b-TSH alone correctly identified 90 % of euthyroid subjects in this group; 10 of 105 apparently euthyroid subjects presented 8-TSH suggesting subclinical hyperthyroidism. While b-TSH was detectable (>0.04uU/ ml) in 8 of 45 (18%) of hyperthyroid patients, all (100%) were abnormal in both b-TSH and r-TSH. 14 of 18 (78 %) of patients with subclinical hyperthyroidism exhibited a blunted TSH response to stimulation (8-TSH <2uU/ml). These results suggest that although the new generation of TSH assays can be a valuable addition to the diagnostic arsenal of thyroid function tests, certain limitations must still be accepted. Specifically, b-TSH in the "grey zone" (0.1-0.2 |uU/ml) appears to be a less than reliable predictor of thyroid function.
Effects of Metoclopramide on the Growth Hormone Response to Galanin in Normal Man

Summary One of the most prominent metabolic ef fects of the systemic administration of the synthetic neu ropeptide galanin in man is the increase in growth hormone (GH) secretion. This stimulating action of galanin is thought to occur directly at the hypothalamic level through the re lease of GHRH. Recently, it has been shown that also dopaminergic drugs may elicit GH secretion through an in crease in hypothalamic GHRH secretion. The aim of this study was to investigate if the action of galanin on GHRH and consequently on GH release may be mediated via dopaminergic pathways evaluating the effects of a potent central dopaminergic receptor blocker, metoclopramide (MCP), on the galanin-induced growth hormone (GH) secre tion in normal subjects. We studied seven young non obese healthy subjects (three females and four males). GH secre tion was evaluated after 45 min iv infusion of porcine galanin (0.5 mg in 100 ml of saline) from 0 to 45 min combined with a 60 min iv infusion of a) saline (100 ml) or b) MCP (10 mg in 100 ml of saline) from -15 to 45 min. In all the seven subjects, during galanin infusion, GH values increased with respect to baseline with peaks occurring between 30 and 60 min after the beginning of galanin infusion. Peak GH values ranged between 3.5 and 15.4 ug/1 (mean 10.4 ± 1.6 ug/1). During MCP infusion no significant differences in the GH response to galanin with respect to saline were observed both when absolute GH levels and GH AUC were examined. In all the subjects GH levels were increased with respect to baseline level with peaks ranging from 4.7 to 20.3 ug/1 (mean 10.6±2.1 ug/1) and occurring between 30 and 60 min after the beginning of galanin infusion. Thus, we conclude that galanin does not elicit GH secretion interacting at the central nervous system level with dopaminergic receptors. It can be hypothesized that galanin interacting with its own receptors may activate at the hypothalamic level GHRH neu rons either directly or indirectly through neurotransmitters other than dopamine.
The classification of edges and the change in multiplicity of an eigenvalue of a real symmetric matrix resulting from the change in an edge value

Abstract We take as given a real symmetric matrix A, whose graph is a tree T, and the eigenvalues of A, with their multiplicities. Each edge of T may then be classified in one of four categories, based upon the change in multiplicity of a particular eigenvalue, when the edge is removed (i.e. the corresponding entry of A is replaced by 0). We show a necessary and suficient condition for each possible classification of an edge. A special relationship is observed among 2-Parter edges, Parter edges and singly Parter vertices. Then, we investigate the change in multiplicity of an eigenvalue based upon a change in an edge value. We show how the multiplicity of the eigenvalue changes depending upon the status of the edge and the edge value. This work explains why, in some cases, edge values have no effect on multiplicities. We also characterize, more precisely, how multiplicity changes with the removal of two adjacent vertices.
On the Matrix Operator Vecp

In this study, we considered a matrix operator that stacks up generically distinct elements of a symmetric matrix in a way different from the well-known "vech" operator. We call this operator the "vecp" operator. The vecp operator is similar to the vech operator, but it is more useful in addressing some statistical problems. We explicitly construct a matrix that transforms vech(A) to vecp(A), where A is a square matrix, and derive various properties of this and related matrices. Applying the vecp operator, we derive convenient and concise expressions of the Wald tests for various null hypotheses regarding the elements of a covariance matrix of a multivariate normal distribution.
Interacting With Implicit Knowing in the Mathematics Classroom

This study explores Grade Seven students’ experiences of doubt and certainty in mathematics. During nine months of (bi-monthly) sessions, students responded to several mathematical prompts; their interactions with each other and with the teacherresearcher were video-taped, transcribed, and coded for learners’ evolving perceptions of what was (a) sufficient to define certainty (including what was experienced as intuitive or counter-intuitive and ways such certainty was interrupted), (b) relevant to the tasks (including understandings that initially dwelled on the periphery of awareness), and (c) mathematically connected. The study is conceptualized within an enactivist view of cognition that emphasizes autonomous, co-emergent, and embodied knowing (Thompson, 2007; Varela, Thompson, & Rosch, 1991), and classes were designed with these principles in mind. It became clear that doubt and certainty emerge from a broader, holistic, understanding that is largely beneath ordinary awareness and is deeply implicated in what we experience as “repeatable context” (Bateson (1964/1972). An important aspect of the study was to bring more of this understanding to awareness. In doing so, Varela’s (Varela & Scharmer, 2000) notion of researcher as empathic coach and Gendlin’s notions of “felt sense” (1962, 1978) and “implicit intricacy” (1991; 2009a) assumed importance. By attending to the holistic sense that points to implicit understanding, it was possible to broaden the scope of what was deemed relevant in selected contexts. It was found that previously subconscious understandings nonetheless influenced learning. Once named (even broadly), implicit understanding coevolved with language in developing mathematical understanding. By attending to external indicators of felt meaning, learners interacted with each others’ implicit understanding, thereby bringing it closer to consciousness and into conversation. Prematurely insisting on clarity and logic precluded awareness of the implicit.
Phytochemical analysis and anticancer activity of the Pithecellobium dulce seed extract in colorectal cancer cells

Abstract Colorectal cancer remains a challenging medical issue worldwide, and utilizing natural products and plants to produce novel, effective and safe therapies against this disease is continuously a sought-after strategy. Fruit and leaf extracts of Pithecellobium dulce (P. dulce) showed potential anticancer properties as they induced apoptosis of breast cancer and Dalton’s lymphoma ascites cells. Thus, the main objective of the current study is to determine whether the seed extract of P. dulce will affect apoptosis, cell cycle, migration, and inflammation of LoVo colorectal cancer cells. The high-resolution liquid chromatography–mass spectrometry was used to determine the chemical composition of the P. dulce seed extract, which revealed the presence of 35 phytochemicals. The findings of this study indicated a significant cytotoxic effect of seeds of this plant in colorectal cancer characterized by induction of apoptosis, cell cycle arrest, and reduction of migration. In addition, the seed extract suppressed several genes that are essential for cancer progression such as MMP2, MMP9, and IL-8, and, on the other hand, upregulated pro-apoptotic genes such as BAX and P53. This study has established P. dulce as a potential and valuable source for providing future therapies against colorectal cancer and other cancers.
Determination of polyphenols in Chinese jujube using ultra-performance liquid chromatography–mass spectrometry

Abstract The polyphenolic composition of the same variety of winter jujube was determined using ultra-performance liquid chromatography–mass spectrometry (UPLC–MS/MS). A metabolomic approach was employed to determine polyphenols at different developmental stages (S1, S2, and S3). The total phenolic content of Chinese jujube was quantified, and the metabolites were statistically analyzed using orthogonal partial least squares discriminant analysis (OPLS-DA) for differential metabolite screening and clustering analysis of key components. The findings revealed that 128 polyphenolic components of Chinese jujube had been identified. Different developmental periods could not be clearly distinguished in principal component analysis, and there was a crossover between S2 and S3 stages. In contrast, the OPLS-DA score plot could effectively distinguish between samples of different developmental periods, and its differential metabolites could be visualized by a volcano plot based on OPLS-DA. Ten phenolic differential metabolites in different developmental periods were clustered and analyzed, among which N′-p-coumaroylguanidinium, N-p-coumaroylbutylamine, caffeoyl guanidinium, N-feruloyl guanidinium, pianoside, isorhamnetin 5-O-hexoside, isorhamnetin O-acetyl-hexoside, quercetin, and lignan O-hexosyl-O-pentoside were higher in the S1 period and chrysoeriol 6-C-hexoside was higher in the S2 and S3 periods. In this study, the differences in jujube polyphenols were elucidated, which provided scientific guidance for the application of jujube polyphenols.
Interactions between the representations of pain and reward suggest dynamic shifts in reference point

With an aim to understand how brains compute the expected utility of mixed prospects, namely those associated with both negative and positive attributes, we designed a task which equated the opportunity to learn about these attributes and their hedonic value. Participants underwent fMRI scanning while they experienced a classical conditioning paradigm where emotionally-neutral faces predicted a probability of pain and reward conforming to a 2 (Electric Pain: high, low) x 2 (Monetary Reward: high, low) factorial design. We found a robust interaction between the anticipation of pain and reward in the BOLD signal. Analysis of simple effects revealed that sensitivity to each attribute increased under high levels of the other attribute. In the bilateral insula and mid-cingulate gyrus sensitivity to pain was greater under high reward, and in the OFC, caudate, ventral striatum and VTA sensitivity to reward was greater under high pain. We speculate that this pattern is due to dynamic shifts in the reference point participants considered to evaluate each attribute.
Monitoring single root hairs using a micro-chambered hydroponics system MiCHy reveals a new mode of action of the aminosteroid U73122

When using chemical probes and inhibitors for cell biological studies, the uniform and rapid access of the chemical to the sample is key for the accuracy of the analysis. Until now, however, this could only be accomplished by using expensive equipment and labor-intensive and often lengthy procedures. Here, we introduce MiCHy, a micro-chambered hydroponics system, as an accessible and versatile method for chemical treatments and demonstrate its use for imaging roots of Arabidopsis thaliana, the major model system for plant cell biological research. Using lipid biosensors in combination with established chemicals, such as the phosphoinositol 4-kinase (PI4K) inhibitor phenylarsine oxide and the phosphoinositide-specific phospholipase C (PI-PLC) inhibitor U73122, we demonstrate the suitability of MiCHy for studying the relationship between growth and lipid dynamics in root hairs. We further reveal novel effects of U73122 on the plasma membrane localization of phosphatidylinositol-4-phosphate 5-kinase 3 (PIP5K3), which is the first evidence demonstrating a role for U73122 besides its role as a PI-PLC inhibitor in plants.
Information-Based Search for an Atmospheric Release Using a Mobile Robot: Algorithm and Experiments

Finding the location and strength of an unknown hazardous release is of paramount importance in emergency response and environmental monitoring; thus, it has been an active research area for several years known as source term estimation (STE). This paper presents a joint Bayesian estimation and planning algorithm to guide a mobile robot to collect informative measurements, allowing the source parameters to be estimated quickly and accurately. The estimation is performed recursively using Bayes’ theorem, where uncertainties in the meteorological and dispersion parameters are considered and the intermittent readings from a low-cost gas sensor are addressed by a novel likelihood function. The planning strategy is designed to maximize the expected utility function based on the estimated information gain of the source parameters. Subsequently, this paper presents the first experimental result of such a system in turbulent, diffusive conditions, in which a ground robot equipped with the low-cost gas sensor responds to the hazardous source simulated by incense sticks. The experimental results demonstrate the effectiveness of the proposed estimation and search algorithm for STE based on the mobile robot and the low-cost sensor.
Interhemispheric inhibition between dorsal premotor and primary motor cortices is released during preparation of unimanual but not bimanual movements

Previous research applying transcranial magnetic stimulation during unimanual reaction time tasks indicates a transient change in the inhibitory influence of dorsal premotor cortex over contralateral primary motor cortex shortly after the presentation of an imperative stimulus. Interhemispheric inhibition from the dorsal premotor cortex to the contralateral primary motor cortex shifts depending on whether the targeted effector representation in the primary motor cortex is selected for movement. Further, the timing of changes in inhibition covaries with the selection demands of the reaction time task. Less is known about modulation of dorsal premotor to primary motor cortex interhemispheric inhibition during the preparation of bimanual movements. In this study, we used a dual coil transcranial magnetic stimulation to measure dorsal premotor to primary motor cortex interhemispheric inhibition between both hemispheres during unimanual and bimanual simple reaction time trials. Interhemispheric inhibition was measured early and late in the “pre-movement period” (defined as the period immediately after the onset of the imperative stimulus and before the beginning of voluntary muscle activity). We discovered that interhemispheric inhibition was more facilitatory early in the pre-movement period compared to late in the pre-movement period during unimanual reaction time trials. In contrast, interhemispheric inhibition was unchanged throughout the pre-movement period during symmetrical bimanual reaction time trials. These results suggest that there is greater interaction between the dorsal premotor cortex and contralateral primary motor cortex during preparation of unimanual actions compared to bimanual actions.
Unconventional stabilization of the human T-cell leukemia virus type 1 immature Gag lattice

Human T-cell leukemia virus type 1 (HTLV-1) has an atypical immature particle morphology compared to other retroviruses. This indicates that these particles are formed in a way that is unique. Here we report the results of cryo-electron tomography (cryo-ET) studies of HTLV-1 virus-like particles (VLPs) assembled in vitro, as well as derived from cells. This work shows that HTLV-1 employs an unconventional mechanism of Gag-Gag interactions to form the immature viral lattice. Analysis of high-resolution structural information from immature CA tubular arrays reveals that the primary stabilizing component in HTLV-1 is CA-NTD. Mutagenesis and biophysical analysis support this observation. This distinguishes HTLV-1 from other retroviruses, in which the stabilization is provided primarily by the CA-CTD. These results are the first to provide structural details of the quaternary arrangement of Gag for an immature deltaretrovirus, and this helps explain why HTLV-1 particles are morphologically distinct.
The Arf-GAP Age2 localizes to the late-Golgi via a conserved amphipathic helix

Arf GTPases are central regulators of the Golgi complex, which serves as the nexus of membrane trafficking pathways in eukaryotic cells. Arf proteins recruit dozens of effectors to modify membranes, sort cargos, and create and tether transport vesicles, and are therefore essential for orchestrating Golgi trafficking. The regulation of Arf activity is controlled by the action of Arf-GEFs, which activate via nucleotide exchange, and Arf-GAPs, which inactivate via nucleotide hydrolysis. The localization dynamics of Arf GTPases and their Arf-GAPs during Golgi maturation have not been reported. Here we use the budding yeast model to examine the temporal localization of the Golgi Arf-GAPs. We also determine the mechanisms used by the Arf-GAP Age2 to localize to the Golgi. We find that the catalytic activity of Age2 and a conserved sequence in the unstructured C-terminal domain of Age2 are both required for Golgi localization. This sequence is predicted to form an amphipathic helix and mediates direct binding of Age2 to membranes in vitro. We also report the development of a probe for sensing active Arf1 in living cells and use this probe to characterize the temporal dynamics of Arf1 during Golgi maturation.
Impact of age versus hearing loss on amplitude modulation frequency selectivity and speech intelligibility

The perception of amplitude modulations (AMs), which is characterized by a frequency-selective process in the modulation domain, is considered critical for speech intelligibility. Previous studies have provided evidence of an age-related decline in AM frequency selectivity, as well as a notable sharpening of AM tuning associated with hearing loss, possibly due to a perceptual advantage resulting from peripheral compression loss. This study aimed to examine whether speech intelligibility in noisy environments would support the following ideas: i) age-related declines in AM tuning might lead to poorer speech intelligibility, and ii) sharper AM tuning associated with hearing loss would not result in improved speech intelligibility. Young (n=10, 22-28 years) and older listeners with normal hearing (n=9, 57–77 years) as well as older listeners with hearing impairment (n=9, 64-77 years) were included in the investigation. All participants had previously taken part in studies on AM frequency selectivity. Speech intelligibility was tested in various listening conditions, including stationary, fluctuating, and competing-speech maskers. Consistent with the hypothesis, the results revealed an age-related increase in speech reception thresholds, with an additional negative impact of hearing loss. These findings motivate further exploration of the relationship between AM frequency selectivity and speech intelligibility in noisy environments.
Motor planning in the human posterior parietal and dorsal premotor cortices includes visuomotor prediction

The dorsal premotor and posterior parietal cortices have been linked to motor planning by electrophysiological recordings and brain imaging. Interestingly, these areas also show increased responses when visual feedback does not match the executed movements, which may indicate an adaptation of the brain’s body representation to a nonstandard visuomotor mapping. Here, we tested whether brain regions that plan a movement also encode predictions about the visuomotor mapping expected during execution. Thus, we combined a delayed movement task with a virtual reality based manipulation of visuomotor congruence during functional magnetic resonance imaging (fMRI). After a delay period, participants executed one of two possible left hand movements; visual movement feedback was provided via a virtual hand model controlled by a data glove. During the delay, a cue specified the to-be-executed movement (or left it ambiguous); and the upcoming mapping of the virtual to real hand movements (congruent or incongruent). Premotor and posterior parietal brain areas showed increased activity, during the delay, when movements were planned (cued > uncued) and when an incongruent > congruent visuomotor mapping was cued. Moreover, there was a significant interaction between both effects in the left anterior intraparietal sulcus (aIPS), the left superior parietal lobe (SPL), and the bilateral dorsal premotor cortex (PMd); each showing strongest activation when specific movements were planned under an expected visuomotor incongruence. These results suggest that motor planning in the dorsal premotor and posterior parietal cortex entails a prediction of the resulting visual movement consequences, which can anticipate nonstandard visuomotor mappings.
Short-Term Effects of Marathon Running in Master Runners: No Evidence of Myocardial Injury

■■■■ The purpose of this investigation was to analyze the short-term effects of marathon running on serum levels of cardiac markers in a group of master runners (> 60 yrs). Ten marathoners (9 male and 1 female; 63 ± 4 yrs) were enrolled in the study. All of them completed the Madrid Marathon (1998). Venous blood was drawn from each subject three times during the study (48 h before the race, immediately after the race, and 24 h post-competition) for the determination of the several biochemical markers, such as total creatine kinase catalytic activity (total CK), mass concentration of creatine kinase isoenzyme MB (CK-MB mass), and cardiac troponin I (TnI-c). The most important finding was that in each sample (preor post-race) serum TnI-c was below the commonly accepted level of 0.1 ng × ml–1 indicative of myocardial injury. Although further research is needed using more complete methodology, our results suggest that marathon running does not have an acute deleterious effect on the hearts of the elderly.