D-Serine and glycine are coagonists of NMDA receptors (NMDARs), but their relative contributions for several NMDAR-dependent processes are unclear. We now report that the alanine-serine-cysteine ...transporter-1 (Asc-1) mediates release of both D-serine and glycine from neurons, and, in turn, this modulates NMDAR synaptic activity. Asc-1 antiporter activity is enhanced by D-isoleucine (D-Ile), which releases D-serine and glycine from Asc-1-transfected cells, primary neuronal cultures, and hippocampal slices. D-Ile has no effect on astrocytes, which do not express Asc-1. We show that D-Ile enhances the long-term potentiation (LTP) in rat and mouse hippocampal CA1 by stimulating Asc-1-mediated endogenous D-serine release. D-Ile effects on synaptic plasticity are abolished by enzymatically depleting D-serine or by using serine racemase knock-out (SR-KO) mice, confirming its specificity and supporting the notion that LTP depends mostly on D-serine release. Conversely, our data also disclose a role of glycine in activating synaptic NMDARs. Although acute enzymatic depletion of D-serine also drastically decreases the isolated NMDAR synaptic potentials, these responses are still enhanced by D-Ile. Furthermore, NMDAR synaptic potentials are preserved in SR-KO mice and are also enhanced by D-Ile, indicating that glycine overlaps with D-serine binding at synaptic NMDARs. Altogether, our results disclose a novel role of Asc-1 in regulating NMDAR-dependent synaptic activity by mediating concurrent non-vesicular release of D-serine and glycine. Our data also highlight an important role of neuron-derived D-serine and glycine, indicating that astrocytic D-serine is not solely responsible for activating synaptic NMDARs.
OBJECTIVE: To compare the effects of a 1-year intervention with a low-carbohydrate and a low-fat diet on weight loss and glycemic control in patients with type 2 diabetes. RESEARCH DESIGN AND ...METHODS: This study is a randomized clinical trial of 105 overweight adults with type 2 diabetes. Primary outcomes were weight and A1C. Secondary outcomes included blood pressure and lipids. Outcome measures were obtained at 3, 6, and 12 months. RESULTS: The greatest reduction in weight and A1C occurred within the first 3 months. Weight loss occurred faster in the low-carbohydrate group than in the low-fat group (P = 0.005), but at 1 year a similar 3.4% weight reduction was seen in both dietary groups. There was no significant change in A1C in either group at 1 year. There was no change in blood pressure, but a greater increase in HDL was observed in the low-carbohydrate group (P = 0.002). CONCLUSIONS: Among patients with type 2 diabetes, after 1 year a low-carbohydrate diet had effects on weight and A1C similar to those seen with a low-fat diet. There was no significant effect on blood pressure, but the low-carbohydrate diet produced a greater increase in HDL cholesterol.
Abstract Objective Most aggressive cancers demonstrate a positive positron emission tomographic (PET) result using18 F-2-fluoro-2-deoxyglucose (FDG), reflecting a glycolytic phenotype. Inhibiting ...insulin secretion provides a method, consistent with published mechanisms, for limiting cancer growth. Methods Eligible patients with advanced incurable cancers had a positive PET result, an Eastern Cooperative Oncology Group performance status of 0 to 2, normal organ function without diabetes or recent weight loss, and a body mass index of at least 20 kg/m2 . Insulin inhibition, effected by a supervised carbohydrate dietary restriction (5% of total kilocalories), was monitored for macronutrient intake, body weight, serum electrolytes, β-hydroxybutyrate, insulin, and insulin-like growth factors-1 and -2. An FDG-PET scan was obtained at study entry and exit. Results Ten subjects completed 26 to 28 d of the study diet without associated unsafe adverse effects. Mean caloric intake decreased 35 ± 6% versus baseline, and weight decreased by a median of 4% (range 0.0–6.1%). In nine patients with prior rapid disease progression, five with stable disease or partial remission on PET scan after the diet exhibited a three-fold higher dietary ketosis than those with continued progressive disease ( n = 4, P = 0.018). Caloric intake ( P = 0.65) and weight loss ( P = 0.45) did not differ in those with stable disease or partial remission versus progressive disease. Ketosis was associated inversely with serum insulin levels ( P = 0.03). Conclusion Preliminary data demonstrate that an insulin-inhibiting diet is safe and feasible in selected patients with advanced cancer. The extent of ketosis, but not calorie deficit or weight loss, correlated with stable disease or partial remission. Further study is needed to assess insulin inhibition as complementary to standard cytotoxic and endocrine therapies.
The closure of in-person laboratories and decreased safety of face-to-face interactions resulting from the COVID-19 pandemic jeopardized the ability of many developmental researchers to continue data ...collection during this time. Disruptions in data collection are particularly damaging to longitudinal studies, in which the testing of different age groups occurs on a continuous basis, and data loss at one time point can have cascading effects across subsequent time points and threaten the viability of the study. In an effort to continue collecting data for a longitudinal study on emotion development started in-person pre-pandemic, we adapted two parent-infant interaction tasks (free-play task and toy removal task) for a remote testing framework. Our procedure for pivoting these tasks to a supervised, remote online testing framework is outlined and the associated strengths and challenges of testing in this format (e.g., feasibility and implementation, testing environment and task setup validity, and accessibility, recruitment, and diversity) are critically evaluated. Considerations for applying this framework to other behavioral tasks are discussed and recommendations are provided.
•South Asian Canadians exhibit an own-race bias in emotion recognition.•White Canadians show similar recognition accuracy for White and South Asian faces.•Emotion recognition improves throughout ...childhood, and from childhood to adulthood.
Adults are less accurate at recognizing emotions expressed by individuals from a different cultural background. However, the research with children is less clear; whereas some studies suggest better emotion recognition for own-race and own-culture faces, others have found no such relationship. The current study examined the influence of race on emotion recognition in children and adults who share a cultural background (i.e., Canadian). Based on previous studies, we hypothesized that participants would demonstrate better emotion recognition for own-race faces. We also hypothesized that emotion recognition would improve across the lifespan (from childhood to adulthood) and as a function of emotion, such that recognition would be better for happy faces than for the other emotions. Children (n = 69; ages 6–10 years; 41 female) and adults (n = 82; mean age = 19.94 years; 72 female) of Western European or South Asian descent were asked to complete a five-alternative forced-choice emotion recognition task (anger, fear, happiness, sadness, and neutral) in which expressions were displayed by White and South Asian faces. As predicted, adults performed better than older children, who performed better than younger children, and participants performed best on happy faces. South Asian participants, but not White participants, performed better when judging own-race faces compared with other-race faces. This finding only partially supports an own-race bias in emotion recognition and may reflect the tendency in the literature to conflate culture and race. More studies are needed to understand cross-race emotion recognition when individuals share the same culture.
Hyperion, a space-based imaging spectrometer Pearlman, J.S.; Barry, P.S.; Segal, C.C. ...
IEEE transactions on geoscience and remote sensing,
2003-June, 2003-06-00, 20030601, Letnik:
41, Številka:
6
Journal Article
Recenzirano
The Hyperion Imaging Spectrometer was the first imaging spectrometer to routinely acquire science-grade data from Earth orbit. Instrument performance was validated and carefully monitored through a ...combination of calibration approaches: solar, lunar, earth (vicarious) and atmospheric observations complemented by onboard calibration lamps and extensive prelaunch calibration. Innovative techniques for spectral calibration of space-based sensors were also tested and validated. Instrument performance met or exceeded predictions including continued operation well beyond the planned one-year program.
Emotion recognition is important for social interaction and communication, yet previous research has identified a cross-cultural emotion recognition deficit: Recognition is less accurate for emotions ...expressed by individuals from a cultural group different than one's own. The current study examined whether social categorization based on race, in the absence of cultural differences, influences emotion recognition in a diverse context. South Asian and White Canadians in the Greater Toronto Area completed an emotion recognition task that required them to identify the seven basic emotional expressions when posed by members of the same two groups, allowing us to tease apart the contributions of culture and social group membership. Contrary to our hypothesis, there was no mutual in-group advantage in emotion recognition: Participants were not more accurate at recognizing emotions posed by their respective racial in-groups. Both groups were more accurate at recognizing expressions when posed by South Asian faces, and White participants were more accurate overall compared to South Asian participants. These results suggest that in a diverse environment, categorization based on race alone does not lead to the creation of social out-groups in a way that negatively impacts emotion recognition.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Background: Obstructive sleep apnoea (OSA) is associated with high cardiovascular morbidity and mortality and is an independent risk factor for hypertension. Novel circulating cardiovascular risk ...markers enabling a more accurate prediction of cardiovascular risk have been identified. Examination of these markers may clarify the increased risk in OSA and contribute to an analysis of the benefits of treatment. Methods: Plasma levels of total cholesterol and triglyceride and activated coagulation factors XIIa and VIIa, factors VII, VIII, XII, fibrinogen, thrombin-antithrombin (TAT), von Willebrand factor antigen (vWFAg), soluble P-selectin (sP-sel), and homocysteine were measured before and after treatment for 1 month with therapeutic or subtherapeutic (control) continuous positive airways pressure (CPAP) in 220 patients with OSA. Results: Levels of activated coagulation factors XIIa, VIIa, TAT and sP-sel were higher in OSA patients at baseline than in unmatched controls, but did not fall with 1 month of therapeutic CPAP treatment. The raised sP-sel levels correlated only with body mass index (p = 0.002). There was a trend towards a significant fall in total cholesterol with therapeutic CPAP (p = 0.06) compared with the control group. In the therapeutic group there was a clinically significant mean fall in total cholesterol of 0.28 mmol/l (95% confidence interval 0.11 to 0.45, p = 0.001) which may reduce cardiovascular risk by about 15%. Conclusion: A number of activated coagulation factors are increased in untreated OSA patients, potentially contributing to vascular risk, but they do not fall with 1 month of CPAP treatment. Nasal CPAP may produce a clinically relevant fall in total cholesterol level, potentially reducing cardiovascular risk, but this needs to be verified in a larger prospective study.
Infants’ visual processing of emotion undergoes significant development across the first year of life, yet our knowledge regarding the mechanisms underlying these advances is limited. Additionally, ...infant emotion processing is commonly examined using static faces, which do not accurately depict real-world emotional displays. The goal of this study was to characterize 7-month-olds’ visual scanning strategies when passively viewing dynamic emotional expressions to examine whether infants modify their scanning patterns depending on the emotion. Eye-tracking measures revealed differential attention towards the critical features (eyes, mouth) of expressions. The eyes captured the greatest attention for angry and neutral faces, and the mouth captured the greatest attention for happy faces. A time-course analysis further elucidated at what point during the trial differential scanning patterns emerged. The current results suggest that 7-month-olds are sensitive to the critical features of emotional expressions and scan them differently depending on the emotion. The scanning patterns presented in this study may serve as a link to understanding how infants begin to differentiate between expressions in the context of emotion recognition.
BACKGROUND AND PURPOSE—Risk of recurrent stroke is high in the first few weeks after transient ischemic attack or stroke and clinical risk prediction tools have only limited accuracy, particularly ...after the hyperacute phase. Previous studies of the predictive value of biomarkers have been small, been done in selected populations, and have not concentrated on the acute phase or on intensively treated populations. We aimed to determine the predictive value of a panel of blood biomarkers in intensively treated patients early after transient ischemic attack and stroke.
METHODS—We studied 14 blood biomarkers related to inflammation, thrombosis, atherogenesis, and cardiac or neuronal cell damage in early transient ischemic attack or ischemic stroke in a population-based study (Oxford Vascular Study). Biomarker levels were related to 90-day risk of recurrent stroke as hazard ratio (95% confidence interval) per decile increase, adjusted for age and sex.
RESULTS—Among 1292 eligible patients, there were 53 recurrent ischemic strokes within 90 days. There were moderate correlations (r=0.40–0.61; P<0.0001) between the inflammatory biomarkers and between the cell damage and thrombotic subsets. Associations with risk of early recurrent stroke were weak, with significant associations limited to interleukin-6 (adjusted hazard ratio, 1.12; 1.01–1.24; P=0.033) and C-reactive protein (adjusted hazard ratio, 1.15; 1.02–1.30; P=0.022) after adjusting for age, sex, hypertension, smoking, and diabetes mellitus although P-selectin seemed to predict stroke after transient ischemic attack (adjusted hazard ratio, 1.28; 1.00–1.63; P=0.046).
CONCLUSIONS—In the largest study to date, we found limited predictive use for early recurrent stroke for a panel of inflammatory, thrombotic, and cell damage biomarkers.
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