70 research outputs found
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Obesity due to melanocortin 4 receptor (MC4R) deficiency is associated with delayed gastric emptying.
OBJECTIVE: People who are severely obese due to melanocortin-4 receptor (MC4R) deficiency experience hyperphagia and impaired fullness after a meal (satiety). Meal-induced satiety is influenced by hormones, such as peptide-YY (PYY), which are released by enteroendocrine cells upon nutrient delivery to the small intestine. DESIGN: We investigated whether gastric emptying and PYY levels are altered in MC4R deficiency. METHODS: Gastric emptying was measured with a gastric scintigraphy protocol using technetium-99m (99 Tcm )-Tin Colloid for 3.5 h in individuals with loss of function MC4R variants and a control group of similar age and weight. In a separate study, we measured plasma PYY levels before and at multiple time points after three standardised meals given to individuals with MC4R deficiency and controls. Fasting PYY (basal secretion) and postprandial PYY levels were measured and the area under the curve and inter-meal peak were calculated. RESULTS: We found that gastric emptying time was significantly delayed and percentage meal retention increased in individuals with MC4R deficiency compared to obese controls. In addition, fasting and mean PYY secretion throughout the day were decreased in MC4R deficiency, whereas postprandial PYY secretion was unaltered. CONCLUSION: Delayed gastric emptying and reduced basal PYY secretion may contribute to impaired satiety in people with obesity due to MC4R deficiency
Traumatic Acute Subdural Hematoma — Major Mortality Reduction in Comatose Patients Treated within Four Hours
To discover which factors contributed to recovery after surgical intracranial decompression, we reviewed the records of 82 consecutive comatose patients with traumatic acute subdural hematoma (ASDH) who were treated in a single center under a uniform protocol. The delay from injury to operation was the factor of greatest therapeutic importance. Patients who underwent surgery within the first four hours had a 30 per cent mortality rate, as compared with 90 per cent in those who had surgery after four hours (
Visualization of Glutamine Transporter Activities in Living Cells Using Genetically Encoded Glutamine Sensors
Glutamine plays a central role in the metabolism of critical biological molecules such as amino acids, proteins, neurotransmitters, and glutathione. Since glutamine metabolism is regulated through multiple enzymes and transporters, the cellular glutamine concentration is expected to be temporally dynamic. Moreover, differentiation in glutamine metabolism between cell types in the same tissue (e.g. neuronal and glial cells) is often crucial for the proper function of the tissue as a whole, yet assessing cell-type specific activities of transporters and enzymes in such heterogenic tissue by physical fractionation is extremely challenging. Therefore, a method of reporting glutamine dynamics at the cellular level is highly desirable. Genetically encoded sensors can be targeted to a specific cell type, hence addressing this knowledge gap. Here we report the development of Föster Resonance Energy Transfer (FRET) glutamine sensors based on improved cyan and yellow fluorescent proteins, monomeric Teal Fluorescent Protein (mTFP)1 and venus. These sensors were found to be specific to glutamine, and stable to pH-changes within a physiological range. Using cos7 cells expressing the human glutamine transporter ASCT2 as a model, we demonstrate that the properties of the glutamine transporter can easily be analyzed with these sensors. The range of glutamine concentration change in a given cell can also be estimated using sensors with different affinities. Moreover, the mTFP1-venus FRET pair can be duplexed with another FRET pair, mAmetrine and tdTomato, opening up the possibility for real-time imaging of another molecule. These novel glutamine sensors will be useful tools to analyze specificities of glutamine metabolism at the single-cell level
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Do conspiracy beliefs form a belief system? Examining the structure and organization of conspiracy beliefs
Despite regular reference to conspiracy theories as a “belief system,” few studies have attempted to explore the structure and organization of conspiracy beliefs beyond an examination of correlations between those beliefs. Employing unique data from two national surveys that includes respondent beliefs in 27 conspiracy theories, we decipher the substantive dimensions along which conspiracy beliefs are organized, as well as subgroupings within those dimensions. We find that variation in these conspiracy beliefs can be accounted for with two dimensions: the first regards partisan and ideological identities, while the other is composed of anti-social orientations, such as narcissism, Machiavellianism, psychopathy, and acceptance of political violence. Importantly, these two dimensions are uncorrelated. We also find that conspiracy beliefs group together by substantive content, such as those regarding partisan actors or science/medicine. Our findings also demonstrate that inferences about the correlates of conspiracy beliefs are highly contingent on the specific conspiracy theories employed by researchers. We provide suggestions for future research in this vein
The psychological and political correlates of conspiracy theory beliefs
Understanding the individual-level characteristics associated with conspiracy theory beliefs is vital to addressing and combatting those beliefs. While researchers have identified numerous psychological and political characteristics associated with conspiracy theory beliefs, the generalizability of those findings is uncertain because they are typically drawn from studies of only a few conspiracy theories. Here, we employ a national survey of 2021 U.S. adults that asks about 15 psychological and political characteristics as well as beliefs in 39 different conspiracy theories. Across 585 relationships examined within both bivariate (correlations) and multivariate (regression) frameworks, we find that psychological traits (e.g., dark triad) and non-partisan/ideological political worldviews (e.g., populism, support for violence) are most strongly related to individual conspiracy theory beliefs, regardless of the belief under consideration, while other previously identified correlates (e.g., partisanship, ideological extremity) are inconsistently related. We also find that the correlates of specific conspiracy theory beliefs mirror those ofconspiracy thinking(the predisposition), indicating that this predisposition operates like an ‘average’ of individual conspiracy theory beliefs. Overall, our findings detail the psychological and political traits of the individuals most drawn to conspiracy theories and have important implications for scholars and practitioners seeking to prevent or reduce the impact of conspiracy theories
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Who Supports QAnon? A Case Study in Political Extremism
The QAnon conspiracy theory has garnered increasing attention as more than 80 pro-QAnon congressional candidates vied for nominations in 2020 primary races. The QAnon movement is widely characterized as "far right" and "growing," but such claims rest on flimsy evidence. Using six public opinion polls from 2018 to 2020, we find that support for QAnon is both meager and stable across time. QAnon also appears to find support among both the political right and left; rather than partisan valence, it is the extremity of political orientations that relates to QAnon support. Finally, we demonstrate that while QAnon supporters are "extreme," they are not so in the ideological sense. Rather, QAnon support is best explained by conspiratorial worldviews, dark triad personality traits, and a predisposition toward other nonnormative behavior. These findings have implications for the study of conspiracy theories and the spread of misinformation and suggest new directions for research on political extremism
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The 2020 presidential election and beliefs about fraud: Continuity or change?
The 2020 presidential campaign was plagued by charges of voter fraud both before and after the election took place. While past literature finds that electoral losers are most likely to express misgivings about election integrity, little else is known about the characteristics of individuals who exhibit these beliefs or how the beliefs have changed over time. Employing national surveys from 2012, 2016, 2018, and 2020, we examine the levels of pre-election expectations of fraud in the event of an electoral loss over time, as well as the individual-level correlates of beliefs in a range of election-related conspiracy theories prominent in 2020. Our analysis reveals that beliefs in election fraud are common and stable across time, and only occasionally relate to partisanship. Moreover, we find that, even accounting for the influence of partisan motivated reasoning, several psychological orientations––conspiracy thinking, anomie, dark triad personality traits, and denialism––play a unique role in promoting perceptions of voter fraud
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American Politics in Two Dimensions: Partisan and Ideological Identities versus Anti‐Establishment Orientations
Contemporary political ills at the mass behavior level (e.g., outgroup aggression, conspiracy theories) are often attributed to increasing polarization and partisan tribalism. We theorize that many such problems are less the product of left‐right orientations than an orthogonal “anti‐establishment” dimension of opinion dominated by conspiracy, populist, and Manichean orientations. Using two national surveys from 2019 and 2020, we find that this dimension of opinion is correlated with several antisocial psychological traits, the acceptance of political violence, and time spent on extremist social media platforms. It is also related to support for populist candidates, such as Trump and Sanders, and beliefs in misinformation and conspiracy theories. While many inherently view politics as a conflict between left and right, others see it as a battle between “the people” and a corrupt establishment. Our findings demonstrate an urgent need to expand the traditional conceptualization of mass opinion beyond familiar left‐right identities and affective orientations
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