30 research outputs found

    Increased requirement of replacement doses of levothyroxine caused by liver cirrhosis

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    Background: Since hypothyroidism is a fairly common dysfunction, levothyroxine (L-T4) is one of the most prescribed medications. Approximately 70% of the administered L-T4 dose is absorbed. The absorption process takes place in the small intestine. Some disorders of the digestive system and some medicines, supplements, and drinks cause L-T4 malabsorption, resulting in failure of serum TSH to be normal. Only rarely liver cirrhosis is mentioned as causing L-T4 malabsorption. Case report: In this study, we report increased requirement of daily doses of l-thyroxine in two patients with the atrophic variant of Hashimoto's thyroiditis and liver cirrhosis. In one patient, this increased requirement could have been contributed by the increased serum levels of the estrogen-dependent thyroxine-binding globulin (TBG), which is the major plasma carrier of thyroid hormones. In the other patient, we switched from tablet L-T4 to liquid L-T4 at the same daily dose. Normalization of TSH levels was achieved, but TSH increased again when she returned to tablet L-T4. Conclusion: Liver cirrhosis can cause increased L-T4 requirements. In addition to impaired bile secretion, the mechanism could be increased serum TBG. A similar increased requirement of L-T4 is observed in other situations characterized by elevation of serum TBG. Because of better intestinal absorption, L-T4 oral liquid formulation is able to circumvent the increased need of L-T4 in these patients

    Heavy Drinking in College Students Is Associated with Accelerated Gray Matter Volumetric Decline over a 2 Year Period

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    Background: Heavy and/or harmful alcohol use while in college is a perennial and significant public health issue. Despite the plethora of cross-sectional research suggesting deleterious effects of alcohol on the brain, there is a lack of literature investigating the longitudinal effects of alcohol consumption on the adolescent brain. We aim to probe the longitudinal effects of college drinking on gray matter change in students during this crucial neurodevelopmental period. Methods: Data were derived from the longitudinal Brain and Alcohol Research in College Students (BARCS) study of whom a subset underwent brain MRI scans at two time points 24 months apart. Students were young adults with a mean age at baseline of about 18.5 years. Based on drinking metrics assessed at both baseline and followup, subjects were classified as sustained abstainers/light drinkers (N = 45) or sustained heavy drinkers (N = 84) based on criteria established in prior literature. Gray matter volumetric change (GMV-c) maps were derived using the longitudinal DARTEL pipeline as implemented in SPM12. GMV-c maps were then subjected to a 1-sample and 2-sample t-test in SPM12 to determine within- and between-group GMV-c differences in drinking groups. Supplementary between-group differences were also computed at baseline only. Results: Within-group analysis revealed significant decline in GMV in both groups across the 2 year followup period. However, tissue loss in the sustained heavy drinking group was more significant, larger per region, and more widespread across regions compared to abstainers/light drinkers. Between-group analysis confirmed the above and showed a greater rate of GMV-c in the heavy drinking group in several brain regions encompassing inferior/medial frontal gyrus, parahippocampus, and anterior cingulate. Supplementary analyses suggest that some of the frontal differences existed at baseline and progressively worsened. Conclusion: Sustained heavy drinking while in college was associated with accelerated GMV decline in brain regions involved with executive functioning, emotional regulation, and memory, which are critical to everyday life functioning. Areas of significant GMV decreases also overlapped largely with brain reward and stress systems implicated in addictive behavior

    A person-centered approach to understanding negative reinforcement drinking among first year college students [post-print]

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    The current study used a person-centered approach (i.e. latent profile analysis) to identify distinct types of college student drinkers based on the predictions of motivational, social learning, and stress and coping theories of maladaptive drinking. A large sample (N = 844; 53% female) of first-year undergraduates from two institutions, public and private, who reported consuming one or more drinks in the last three months completed measures of depressive and anxiety symptoms, positive alcohol-outcome expectancies, negative life events, social support, drinking motives, drinking level and drinking-related problems. Latent profile analysis revealed a small subgroup of individuals (n = 81, 9%) who conformed to the anticipated high-risk profile; specifically, this group demonstrated high levels of negative affect, coping motives, drinks per week, and drinking-related problems. However, additional groups emerged that showed patterns inconsistent with the proposed vulnerability profile (e.g., high negative affect, positive expectancies, and negative life events, but relatively low drinking levels). Findings from our person-centered approach showing the presence of groups both consistent and inconsistent with the predictions of motivational, social learning, and stress and coping theories highlight the need to identify and target certain college students for prevention and intervention of negative affect-related drinking

    Effects of drinking patterns on prospective memory performance in college students [pre-print]

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    OBJECTIVE: Traditional college students are at a critical juncture in the development of prospective memory (PM). Their brains are vulnerable to the effects of alcohol. METHOD: There were 123 third and fourth year college students, 19-23 years old, who completed the Self-Rating Effects of Alcohol (SREA), Modified Timeline Follow-back (TFLB), Brief Young Adult Alcohol Consequences Scale (BYAACS), and Alcohol Effects Questionnaire (AEQ) once per month on a secure online database, as reported elsewhere (Dager et al., 2013). Data from the 6 months immediately before memory testing were averaged. In a single testing session participants were administered the Mini International Neuropsychiatric Interview-Diagnostic and Statistical Manual for Mental Disorders-Fourth Edition-Text Revision (MINI-DSM-IV-TR), measures of PM (event-based and time-based), and retrospective memory (RM). Based on the average score of six consecutive monthly responses to the SREA, TLFB, and AEQ, students were classified as nondrinkers, light drinkers, or heavy drinkers (as defined previously; Dager et al., 2013). Alcohol-induced amnesia (blackout) was measured with the BYAACS. RESULTS: We found a relationship between these alcohol use classifications and time-based PM, such that participants who were classified as heavier drinkers were more likely to forget to perform the time-based PM task. We also found that self-reported alcohol-induced amnesia (blackouts) during the month immediately preceding memory testing was associated with lower performance on the event-based PM task. Participants\u27 ability to recall the RM tasks suggested the PM items were successfully encoded even when they were not carried out, and we observed no relationship between alcohol use and RM performance. CONCLUSION: Heavy alcohol use in college students may be related to impairments in PM. (PsycINFO Database Recor

    fMRI Response During Figural Memory Task Performance in College Drinkers [pre-print]

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    Rationale: 18-25-year-olds show the highest rates of alcohol use disorders (AUD) and heavy drinking, which may have critical neurocognitive implications. Regions subserving memory may be particularly susceptible to alcohol-related impairments. Objective: We used blood oxygen level-dependent (BOLD) functional magnetic resonance imaging (fMRI) to examine the neural correlates of visual encoding and recognition among heavy drinking college students. We predicted that heavy drinkers would show worse memory performance and increased frontal/parietal activation and decreased hippocampal response during encoding. Methods: Participants were 23 heavy drinkers and 33 demographically matched light drinkers, ages 18-20, characterized using quantity/frequency of drinking and AUD diagnosis. Participants performed a figural encoding and recognition task during fMRI. BOLD response during encoding was modeled based on whether each stimulus was subsequently recognized or forgotten (i.e., correct vs. incorrect encoding). Results: There were no group differences in behavioral performance. Compared to light drinkers, heavy drinkers showed: 1) greater BOLD response during correct encoding in right hippocampus/medial temporal, right dorsolateral prefrontal, left inferior frontal, and bilateral posterior parietal cortices; 2) less left inferior frontal activation and greater bilateral precuneus deactivation during incorrect encoding; and 3) less bilateral insula response during correct recognition (clusters \u3e10,233ul, p Conclusions: This is the first investigation of the neural substrates of figural memory among heavy drinking older adolescents. Heavy drinkers demonstrated compensatory hyperactivation of memory-related areas during correct encoding, greater deactivation of default mode regions during incorrect encoding, and reduced recognition-related response. Results could suggest use of different encoding and recognition strategies among heavy drinkers

    Adaptive resistance of melanoma cells to RAF inhibition via reversible induction of a slowly dividing de‐differentiated state

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    Abstract Treatment of BRAF‐mutant melanomas with MAP kinase pathway inhibitors is paradigmatic of the promise of precision cancer therapy but also highlights problems with drug resistance that limit patient benefit. We use live‐cell imaging, single‐cell analysis, and molecular profiling to show that exposure of tumor cells to RAF/MEK inhibitors elicits a heterogeneous response in which some cells die, some arrest, and the remainder adapt to drug. Drug‐adapted cells up‐regulate markers of the neural crest (e.g., NGFR), a melanocyte precursor, and grow slowly. This phenotype is transiently stable, reverting to the drug‐naïve state within 9 days of drug withdrawal. Transcriptional profiling of cell lines and human tumors implicates a c‐Jun/ECM/FAK/Src cascade in de‐differentiation in about one‐third of cell lines studied; drug‐induced changes in c‐Jun and NGFR levels are also observed in xenograft and human tumors. Drugs targeting the c‐Jun/ECM/FAK/Src cascade as well as BET bromodomain inhibitors increase the maximum effect (E max) of RAF/MEK kinase inhibitors by promoting cell killing. Thus, analysis of reversible drug resistance at a single‐cell level identifies signaling pathways and inhibitory drugs missed by assays that focus on cell populations

    Heavy Drinking in College Students Is Associated with Accelerated Gray Matter Volumetric Decline over a 2 Year Period

    Get PDF
    Background: Heavy and/or harmful alcohol use while in college is a perennial and significant public health issue. Despite the plethora of cross-sectional research suggesting deleterious effects of alcohol on the brain, there is a lack of literature investigating the longitudinal effects of alcohol consumption on the adolescent brain. We aim to probe the longitudinal effects of college drinking on gray matter change in students during this crucial neurodevelopmental period.Methods: Data were derived from the longitudinal Brain and Alcohol Research in College Students (BARCS) study of whom a subset underwent brain MRI scans at two time points 24 months apart. Students were young adults with a mean age at baseline of about 18.5 years. Based on drinking metrics assessed at both baseline and followup, subjects were classified as sustained abstainers/light drinkers (N = 45) or sustained heavy drinkers (N = 84) based on criteria established in prior literature. Gray matter volumetric change (GMV-c) maps were derived using the longitudinal DARTEL pipeline as implemented in SPM12. GMV-c maps were then subjected to a 1-sample and 2-sample t-test in SPM12 to determine within- and between-group GMV-c differences in drinking groups. Supplementary between-group differences were also computed at baseline only.Results: Within-group analysis revealed significant decline in GMV in both groups across the 2 year followup period. However, tissue loss in the sustained heavy drinking group was more significant, larger per region, and more widespread across regions compared to abstainers/light drinkers. Between-group analysis confirmed the above and showed a greater rate of GMV-c in the heavy drinking group in several brain regions encompassing inferior/medial frontal gyrus, parahippocampus, and anterior cingulate. Supplementary analyses suggest that some of the frontal differences existed at baseline and progressively worsened.Conclusion: Sustained heavy drinking while in college was associated with accelerated GMV decline in brain regions involved with executive functioning, emotional regulation, and memory, which are critical to everyday life functioning. Areas of significant GMV decreases also overlapped largely with brain reward and stress systems implicated in addictive behavior

    Chlorophyll fluorescence screening of Arabidopsis thaliana for CO2 sensitive photorespiration and photoinhibition mutants

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    Exposure of Arabidopsis thaliana (L.) photorespiration mutants to air leads to a rapid decline in the Fv/Fm chlorophyll fluorescence parameter, reflecting a decline in PSII function and an onset of photoinhibition. This paper demonstrates that chlorophyll fluorescence imaging of Fv/Fm can be used as an easy and efficient means of detecting Arabidopsis mutants that are impaired in various aspects of photorespiration. This screen was developed to be sensitive and high throughput by the use of exposure to zero CO2 conditions and the use of array grids of 1-week-old Arabidopsis seedlings as the starting material for imaging. Using this procedure, we screened ∼25000 chemically mutagenised M2 Arabidopsis seeds and recovered photorespiration phenotypes (reduction in F v/Fm at low CO2) at a frequency of ∼4 per 1000 seeds. In addition, we also recovered mutants that showed reduced F v/Fm at high CO2. Of this group, we detected a novel 'reverse photorespiration' phenotype that showed a high CO2 dependent reduction in Fv/Fm. This chlorophyll fluorescence screening technique promises to reveal novel mutants associated with photorespiration and photoinhibition

    Postpartum sexual quality of life : scale development and psychometric properties assessment in Iran

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    To develop and assess the psychometric properties of the Postpartum Sexual Quality of Life Scale (PSQLS) in Iran. We employed a mixed-method approach. In the qualitative phase (17 interviews and two focus groups), we generated items for the scale. In the quantitative phase (N = 282), we assessed the psychometric properties of the pre-final version. The final version contained 22 items. Exploratory factor analysis indicated a 5-factor solution that jointly accounted for 59.6% of the variance. Cronbach’s alpha coefficient was 0.87. The PSQLS showed good validity and reliability and could be used to evaluate women’s postpartum sexual life

    Increased Requirement of Replacement Doses of Levothyroxine Caused by Liver Cirrhosis

    No full text
    BackgroundSince hypothyroidism is a fairly common dysfunction, levothyroxine (L-T4) is one of the most prescribed medications. Approximately 70% of the administered L-T4 dose is absorbed. The absorption process takes place in the small intestine. Some disorders of the digestive system and some medicines, supplements, and drinks cause L-T4 malabsorption, resulting in failure of serum TSH to be normal. Only rarely liver cirrhosis is mentioned as causing L-T4 malabsorption.Case reportIn this study, we report increased requirement of daily doses of l-thyroxine in two patients with the atrophic variant of Hashimoto’s thyroiditis and liver cirrhosis. In one patient, this increased requirement could have been contributed by the increased serum levels of the estrogen-dependent thyroxine-binding globulin (TBG), which is the major plasma carrier of thyroid hormones. In the other patient, we switched from tablet L-T4 to liquid L-T4 at the same daily dose. Normalization of TSH levels was achieved, but TSH increased again when she returned to tablet L-T4.ConclusionLiver cirrhosis can cause increased L-T4 requirements. In addition to impaired bile secretion, the mechanism could be increased serum TBG. A similar increased requirement of L-T4 is observed in other situations characterized by elevation of serum TBG. Because of better intestinal absorption, L-T4 oral liquid formulation is able to circumvent the increased need of L-T4 in these patients
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