Divergent landscapes of A-to-I editing in postmortem and living human brain.

Adenosine-to-inosine (A-to-I) editing is a prevalent post-transcriptional RNA modification within the brain. Yet, most research has relied on postmortem samples, assuming it is an accurate representation of RNA biology in the living brain. We challenge this assumption by comparing A-to-I editing between postmortem and living prefrontal cortical tissues. Major differences were found, with over 70,000 A-to-I sites showing higher editing levels in postmortem tissues. Increased A-to-I editing in postmortem tissues is linked to higher ADAR1 and ADARB1 expression, is more pronounced in non-neuronal cells, and indicative of postmortem activation of inflammation and hypoxia. Higher A-to-I editing in living tissues marks sites that are evolutionarily preserved, synaptic, developmentally timed, and disrupted in neurological conditions. Common genetic variants were also found to differentially affect A-to-I editing levels in living versus postmortem tissues. Collectively, these discoveries illuminate the nuanced functions and intricate regulatory mechanisms of RNA editing within the human brain.

A study of gene expression in the living human brain.

A goal of medical research is to determine the molecular basis of human brain health and illness. One way to achieve this goal is through observational studies of gene expression in human brain tissue. Due to the unavailability of brain tissue from living people, most such studies are performed using tissue from postmortem brain donors. An assumption underlying this practice is that gene expression in the postmortem human brain is an accurate representation of gene expression in the living human brain. Here, this assumption - which, until now, had not been adequately tested - is tested by comparing human prefrontal cortex gene expression between 275 living samples and 243 postmortem samples. Expression levels differed significantly for nearly 80% of genes, and a systematic examination of alternative explanations for this observation determined that these differences are not a consequence of cell type composition, RNA quality, postmortem interval, age, medication, morbidity, symptom severity, tissue pathology, sample handling, batch effects, or computational methods utilized. Analyses integrating the data generated for this study with data from earlier landmark studies that used tissue from postmortem brain donors showed that postmortem brain gene expression signatures of neurological and mental illnesses, as well as of normal traits such as aging, may not be accurate representations of these gene expression signatures in the living brain. By using tissue from large cohorts living people, future observational studies of human brain biology have the potential to (1) determine the medical research questions that can be addressed using postmortem tissue as a proxy for living tissue and (2) expand the scope of medical research to include questions about the molecular basis of human brain health and illness that can only be addressed in living people (e.g., "What happens at the molecular level in the brain as a person experiences an emotion?").

Efficacy and Safety of the Adjuvant Use of Probiotic Bacillus clausii Strains in Pediatric Irritable Bowel Syndrome: A Randomized, Double-Blind, Placebo-Controlled Study.

OBJECTIVES: Current irritable bowel syndrome (IBS) treatments have limited efficacy and probiotics like Bacillus clausii (B. clausii) were found to be effective in the management of several gastrointestinal disorders. This phase III trial assessed the efficacy and safety of adding B. clausii (four strains: O/C, N/R, SIN, T), versus placebo, to conventional treatment of pediatric IBS in Mexico. METHODS: Patients aged 6-17 years 11 months with IBS (Rome IV) for at least 2 months were randomized to receive either B. clausii (oral suspension, total dose 4 billion spores/day) or placebo once daily for 8 weeks. All patients also received conventional treatment. The primary endpoint was the difference in the proportion of patients with clinical improvements at Week 8 (Global Assessment Questions [GAQ]). Secondary endpoints included responders by Subject's Global Assessment of Relief for Children with IBS (SGARC); number/consistency of stools; abdominal distention/bloating; abdominal pain/intensity; and IBS behavior. RESULTS: 73.6% (95% confidence interval [CI] 67.3-80.0; B. clausii n = 129) and 78.5% (95% CI 72.5-84.4; placebo n = 130) of patients had symptom improvement (p = 0.8182). For Week 8 SGARC, 19.2% (B. clausii) and 20.9% (placebo) reported complete symptom relief. Stool evaluations, bloating, abdominal pain/intensity, and IBS behavior were similar between groups. Both treatments were well tolerated. CONCLUSION: No significant differences in efficacy between B. clausii and placebo were demonstrated in addition to conventional treatment. The sample size calculation was based on an expected placebo/conventional treatment response of 30-40%. However, the actual treatment response observed was 80% and, thus, a study with larger population would be warranted. In addition, this study was conducted during the COVID-19 pandemic, when such controlled social conditions may have resulted in better diet, greater family stability, less psychological stress, and lower risk of infections exacerbating IBS, thereby improving symptoms in both groups. EUDRACT NUMBER: 2018-004519-31.

Correlation of Personal Experience and Acquired Knowledge With Intent to Recommend Adjunctive Osteopathic Manipulative Treatment or Yoga for Patients With Chronic Low Back Pain.

CONTEXT: Osteopathic manipulative treatment (OMT) and yoga are both recommended by systematic reviews in the evidence-based research literature for low back pain management. It is unknown, to the authors' knowledge, what the effect of personal experience with OMT or yoga, reading research articles on OMT or yoga, or both will have on medical students' recommendations for these treatment options to future patients with chronic low back pain. OBJECTIVE: To evaluate the likelihood of osteopathic medical students recommending OMT or yoga to treat patients with chronic low back pain based on their personal experience or reading research articles that recommend OMT or yoga for patients with chronic low back pain. METHODS: In this prospective cohort study, researchers administered an anonymous 18-question online survey for osteopathic medical students. The survey included a patient vignette, 2 evidence-based articles, and multiple choice, yes/no, and Likert-type questions. Participants were recruited via email from all 4 years of medical school. Between-group differences in proportions were assessed with descriptive statistics and χ2 tests; differences within groups were assessed with the McNemar test; and Fischer exact tests were used when expected cell counts were less than 5. RESULTS: A total of 180 participants (100 male, 80 female) completed the study. Personal experience increased the likelihood of osteopathic medical students recommending OMT (P<.018) or yoga (P<.001) to a future patient or to a patient in a case vignette (P<.05) with chronic low back pain. Students who read research articles were more likely to recommend OMT to the case patient and future patients before and after reading the intervention article regardless of their experience (P<.001). CONCLUSION: Personal experience and reading evidence-based research may increase the likelihood that osteopathic medical students will recommend OMT to future patients with chronic low back pain.

Genetic Variation in Choline-Metabolizing Enzymes Alters Choline Metabolism in Young Women Consuming Choline Intakes Meeting Current Recommendations.

Single nucleotide polymorphisms (SNPs) in choline metabolizing genes are associated with disease risk and greater susceptibility to organ dysfunction under conditions of dietary choline restriction. However, the underlying metabolic signatures of these variants are not well characterized and it is unknown whether genotypic differences persist at recommended choline intakes. Thus, we sought to determine if common genetic risk factors alter choline dynamics in pregnant, lactating, and non-pregnant women consuming choline intakes meeting and exceeding current recommendations. Women (n = 75) consumed 480 or 930 mg choline/day (22% as a metabolic tracer, choline-d9) for 10-12 weeks in a controlled feeding study. Genotyping was performed for eight variant SNPs and genetic differences in metabolic flux and partitioning of plasma choline metabolites were evaluated using stable isotope methodology. CHKA rs10791957, CHDH rs9001, CHDH rs12676, PEMT rs4646343, PEMT rs7946, FMO3 rs2266782, SLC44A1 rs7873937, and SLC44A1 rs3199966 altered the use of choline as a methyl donor; CHDH rs9001 and BHMT rs3733890 altered the partitioning of dietary choline between betaine and phosphatidylcholine synthesis via the cytidine diphosphate (CDP)-choline pathway; and CHKA rs10791957, CHDH rs12676, PEMT rs4646343, PEMT rs7946 and SLC44A1 rs7873937 altered the distribution of dietary choline between the CDP-choline and phosphatidylethanolamine N-methyltransferase (PEMT) denovo pathway. Such metabolic differences may contribute to disease pathogenesis and prognosis over the long-term.

Genetic impairments in folate enzymes increase dependence on dietary choline for phosphatidylcholine production at the expense of betaine synthesis.

Although single nucleotide polymorphisms (SNPs) in folate-mediated pathways predict susceptibility to choline deficiency during severe choline deprivation, it is unknown if effects persist at recommended intakes. Thus, we used stable isotope liquid chromatography-mass spectrometry (LC-MS) methodology to examine the impact of candidate SNPs on choline metabolism in a long-term, randomized, controlled feeding trial among pregnant, lactating, and nonpregnant (NP) women consuming 480 or 930 mg/d choline (22% as choline-d9, with d9 indicating a deuterated trimethyl amine group) and meeting folate-intake recommendations. Variants impairing folate metabolism, methylenetetrahydrofolate reductase (MTHFR) rs1801133, methionine synthase (MTR) rs1805087 [wild-type (WT)], MTR reductase (MTRR) rs1801394, and methylenetetrahydrofolate dehydrogenase-methenyltetrahydrofolate cyclohydrolase-formyltetrahydrofolate synthetase (MTHFD1) rs2236225, influenced choline dynamics, frequently through interactions with reproductive state and choline intake, with fewer genotypic alterations observed among pregnant women. Women with these variants partitioned more dietary choline toward phosphatidylcholine (PC) biosynthesis via the cytidine diphosphate (CDP)-choline pathway at the expense of betaine synthesis even when use of betaine as a methyl donor was increased. Choline intakes of 930 mg/d restored partitioning of dietary choline between betaine and CDP-PC among NP (MTHFR rs1801133 and MTR rs1805087 WT) and lactating (MTHFD1 rs2236225) women with risk genotypes. Overall, our findings indicate that loss-of-function variants in folate-metabolizing enzymes strain cellular PC production, possibly via impaired folate-dependent phosphatidylethanolamine-N-methyltransferase (PEMT)-PC synthesis, and suggest that women with these risk genotypes may benefit from choline intakes exceeding current recommendations.-Ganz, A. B., Shields, K., Fomin, V. G., Lopez, Y. S., Mohan, S., Lovesky, J., Chuang, J. C., Ganti, A., Carrier, B., Yan, J., Taeswuan, S., Cohen, V. V., Swersky, C. C., Stover, J. A., Vitiello, G. A., Malysheva, O. V., Mudrak, E., Caudill, M. A. Genetic impairments in folate enzymes increase dependence on dietary choline for phosphatidylcholine production at the expense of betaine synthesis.

A Case of Auricular Pseudocyst.

BACKGROUND: Auricular pseudocyst is a rare, asymptomatic, cystic-like swelling of the auricle that may pose a diagnostic challenge to the clinician. If inadequately treated, recurrences and ear deformities may ensue. OBJECTIVE: The authors present a case of auricular pseudocyst in a previously healthy 43-year-old man. Aetiologies, histology, differential diagnosis, and treatment modalities are discussed.

Glucocorticoid Regulation of Food-Choice Behavior in Humans: Evidence from Cushing's Syndrome.

The mechanisms by which glucocorticoids regulate food intake and resulting body mass in humans are not well-understood. One potential mechanism could involve modulation of reward processing, but human stress models examining effects of glucocorticoids on behavior contain important confounds. Here, we studied individuals with Cushing's syndrome, a rare endocrine disorder characterized by chronic excess endogenous glucocorticoids. Twenty-three patients with Cushing's syndrome (13 with active disease; 10 with disease in remission) and 15 controls with a comparably high body mass index (BMI) completed two simulated food-choice tasks (one with "explicit" task contingencies and one with "probabilistic" task contingencies), during which they indicated their objective preference for viewing high calorie food images vs. standardized pleasant, unpleasant, and neutral images. All participants also completed measures of food craving, and approximately half of the participants provided 24-h urine samples for assessment of cortisol and cortisone concentrations. Results showed that on the explicit task (but not the probabilistic task), participants with active Cushing's syndrome made fewer food-related choices than participants with Cushing's syndrome in remission, who in turn made fewer food-related choices than overweight controls. Corroborating this group effect, higher urine cortisone was negatively correlated with food-related choice in the subsample of all participants for whom these data were available. On the probabilistic task, despite a lack of group differences, higher food-related choice correlated with higher state and trait food craving in active Cushing's patients. Taken together, relative to overweight controls, Cushing's patients, particularly those with active disease, displayed a reduced vigor of responding for food rewards that was presumably attributable to glucocorticoid abnormalities. Beyond Cushing's, these results may have relevance for elucidating glucocorticoid contributions to food-seeking behavior, enhancing mechanistic understanding of weight fluctuations associated with oral glucocorticoid therapy and/or chronic stress, and informing the neurobiology of neuropsychiatric conditions marked by abnormal cortisol dynamics (e.g., major depression, Alzheimer's disease).

A prospective study of appetite and food craving in 30 patients with Cushing's disease.

CONTEXT: Glucocorticoid (GC) exposure increases food intake, but the mechanisms in humans are not known. Investigation of appetite and food craving has not been done in patients with chronic GC exposure due to Cushing's disease (CD), either before or after treatment, and could provide insight into mechanisms of food intake and obesity in these patients. PURPOSE: To examine whether surgical remission of CD changes appetite (prospective consumption, hunger, satisfaction, and fullness) and food cravings (sweet, salty, fatty, and savory); and to identify predictors of appetite and craving in CD remission. METHODS: 30 CD patients, mean age 40.0 years (range 17-70), mean BMI 32.3 ± 6.4, were prospectively studied before and at a mean of 17.4 mo. after remission. At each visit fasting and post-test meal (50% carbohydrate, 35% protein, 15% fat) appetite and craving scores were assessed. RESULTS: Remission decreased prospective consumption, sweet and savory craving (p < 0.05), but did not change hunger, satisfaction, fullness, or fat craving, despite decreases in BMI and fat mass. In CD remission, serum cortisol predicted lower satisfaction and fullness, and masses of abdominal fat depots predicted higher hunger and consumption (p < 0.05). CONCLUSIONS: Chronic GC exposure in CD patients may stimulate the drive to eat by enhancing craving, rather than regulating the sensation of hunger. Continued alterations in appetite regulation due to abdominal fat mass and circulating cortisol could play a role in the cardiovascular and metabolic risk that has been reported in CD patients despite remission.