Assessing the impact of storage time on the stability of stool microbiota richness, diversity, and composition

Background New technologies like next-generation sequencing have led to a proliferation of studies investigating the role of the gut microbiome in human health, particularly population-based studies that rely upon participant self-collection of samples. However, the impact of methodological differences in sample shipping, storage, and processing are not well-characterized for these types of studies, especially when transit times may exceed 24 h. The aim of this study was to experimentally assess microbiota stability in stool samples stored at 4 °C for durations of 6, 24, 48, 72, and 96 h with no additives to better understand effects of variable shipping times in population-based studies. These data were compared to a baseline sample that was immediately stored at − 80 °C after stool production. Results Compared to the baseline sample, we found that the alpha-diversity metrics Shannon’s and Inverse Simpson’s had excellent intra-class correlations (ICC) for all storage durations. Chao1 richness had good to excellent ICC. We found that the relative abundances of bacteria in the phyla Verrucomicrobia, Actinobacteria, and Proteobacteria had excellent ICC with baseline for all storage durations, while Firmicutes and Bacteroidetes ranged from moderate to good. We interpreted the ICCs as follows: poor: ICC < 0.50, moderate: 0.50 < ICC < 0.75, good: 0.75 < ICC < 0.90, and excellent: ICC > 0.90. Using the Bray–Curtis dissimilarity index, we found that the greatest change in community composition occurred between 0 and 24 h of storage, while community composition remained relatively stable for subsequent storage durations. Samples showed strong clustering by individual, indicating that inter-individual variability was greater than the variability associated with storage time. Conclusions The results of this analysis suggest that several measures of alpha diversity, relative abundance, and overall community composition are robust to storage at 4 °C for up to 96 h. We found that the overall community richness was influenced by storage duration in addition to the relative abundances of sequences within the Firmicutes and Bacteroidetes phyla. Finally, we demonstrate that inter-individual variability in microbiota composition was greater than the variability due to changing storage durations.

Muscle Bioenergetics and Cognitive Executive Function: The SOMMA Study Baseline

Better executive function has been associated with faster walking speed, but the basis for this association is unclear. Systemic factors appear to contribute mitochondrial function across multiple tissues including muscle and brain. We hypothesized that muscle-based measures of bioenergetics capacity would be associated with cognitive function at SOMMA’s baseline. MRI-based ATPMAX and muscle fiber respirometry-based max OXPHOS were correlated with scores on the MoCA (mean: 24.0; SD: 3.2); Trails B (mean: 138 seconds; SD: 73) and the Digit Symbol Coding Tests (mean: 50.8; SD: 14.9). The spearman correlations between ATPmax and the three measures were: 0.10 (p=0.29); -0.20 (p=0.03) and 0.16 (p=0.09), respectively. The association between max OXPHOS were: 0.18 (p=0.02); -0.20 (p&lt;0.01) and 0.11 (p=0.13), respectively. Some associations appeared stronger in men than women. Gender interactions and whether energetics mediate some of the association between cognitive function and gait speed will be explored in the full baseline sample.

Is adolescents’ progress in reading comprehension served by particular attributional views in addition to learning the reading comprehension strategies of reciprocal teaching? A mixed-methods intervention study

<p>A mixed-methods quasi-experimental design was used to identify relationships between adolescent students’ attributions for their reading performance and their reading achievement by gathering baseline data from year 9 and 10 students (n = 175) and then investigating the effects of two stages of intervention on a treatment group (n = 22) and a comparison group (n = 16). The first stage of intervention used the instructional activity of reciprocal teaching to teach students cognitive strategies to improve reading comprehension. The second stage of the intervention combined on-going reciprocal teaching with attributional-retraining, aimed at to developing internal attributions for reading performance; specifically effort-related attributions rather than attributions focussing on ability. A baseline sample (which included the treatment and comparison samples as well as students from the wider year 9 and 10 cohort) completed a questionnaire about their attributions for their reading performance. There was no evidence of the hypothesised correlation between a measure of students’ incremental mindset (internal, unstable and controllable attribution) and standardised measures of reading comprehension. Analysis of the attribution data for the baseline sample showed evidence that internal and external attributions are not, as theorised, two ends of the same continuum, rather they are separate constructs, albeit negatively correlated. The treatment and comparison groups completed a standardised reading comprehension test and the attribution questionnaire at four time points: pre-intervention; between the two stages of intervention; post-intervention; and delayed post-intervention. A sub-sample of six students, representing a spectrum of reading achievement was interviewed to develop a better understanding of the responses provided in the questionnaire. The combined interventions had no significant effect on students’ attributions for their reading performance or on their reading comprehension achievement. Conversely, the first stage of the intervention, reciprocal teaching, did have a significant effect on the treatment group’s reading comprehension achievement immediately following the intervention and the group were observed eagerly participating in the activity with significantly increased engagement. The combined qualitative and quantitative data from the interventions provided evidence about the complexity of adolescents’ attributional beliefs. Students responded with a wide variety of beliefs that did not conform to the theorised pattern of attributional beliefs. The findings raise questions about how students form attributions for their successes and failures, in particular the direction of the causal relationship between achievement and attributional beliefs.</p>

Is adolescents’ progress in reading comprehension served by particular attributional views in addition to learning the reading comprehension strategies of reciprocal teaching? A mixed-methods intervention study

<p>A mixed-methods quasi-experimental design was used to identify relationships between adolescent students’ attributions for their reading performance and their reading achievement by gathering baseline data from year 9 and 10 students (n = 175) and then investigating the effects of two stages of intervention on a treatment group (n = 22) and a comparison group (n = 16). The first stage of intervention used the instructional activity of reciprocal teaching to teach students cognitive strategies to improve reading comprehension. The second stage of the intervention combined on-going reciprocal teaching with attributional-retraining, aimed at to developing internal attributions for reading performance; specifically effort-related attributions rather than attributions focussing on ability. A baseline sample (which included the treatment and comparison samples as well as students from the wider year 9 and 10 cohort) completed a questionnaire about their attributions for their reading performance. There was no evidence of the hypothesised correlation between a measure of students’ incremental mindset (internal, unstable and controllable attribution) and standardised measures of reading comprehension. Analysis of the attribution data for the baseline sample showed evidence that internal and external attributions are not, as theorised, two ends of the same continuum, rather they are separate constructs, albeit negatively correlated. The treatment and comparison groups completed a standardised reading comprehension test and the attribution questionnaire at four time points: pre-intervention; between the two stages of intervention; post-intervention; and delayed post-intervention. A sub-sample of six students, representing a spectrum of reading achievement was interviewed to develop a better understanding of the responses provided in the questionnaire. The combined interventions had no significant effect on students’ attributions for their reading performance or on their reading comprehension achievement. Conversely, the first stage of the intervention, reciprocal teaching, did have a significant effect on the treatment group’s reading comprehension achievement immediately following the intervention and the group were observed eagerly participating in the activity with significantly increased engagement. The combined qualitative and quantitative data from the interventions provided evidence about the complexity of adolescents’ attributional beliefs. Students responded with a wide variety of beliefs that did not conform to the theorised pattern of attributional beliefs. The findings raise questions about how students form attributions for their successes and failures, in particular the direction of the causal relationship between achievement and attributional beliefs.</p>

Smell distortions: Prevalence, longevity and impact of parosmia in a population-based, longitudinal study spanning 10 years

Parosmia, experiences of distorted smell sensations, is a common consequence of covid-19. The phenomenon is not well understood in terms of its impact and long-term outcomes. We examined parosmia in a population-based sample from the Betula study that was conducted in Umeå in northern Sweden (baseline data collected in 1998-2000). We used a baseline sample of 2168 individuals aged 35-90 years and with no cognitive impairment at baseline. We investigated the prevalence of parosmia and, using regression analyses, its relationship to other olfactory and cognitive variables and quality of life. Benefitting from the longitudinal study design, we also assessed the persistence of parosmia over 5 and 10 years prospectively. Parosmia was prevalent in 5% of the population (n=104) and was often co-occurring with phantosmia (“olfactory hallucinations”), but was not associated with lower self-rated overall quality of life or poor performance on olfactory or cognitive tests. For some individuals, parosmia was retained 5 years (17%) or even 10 years later (10%). Thus, parosmia is relative common in the population, and can be persistent for some individuals. This work provides rare insights into the expected impact of, and recovery from parosmia, with implications for those suffering from qualitative olfactory dysfunction following covid-19.

Sequential Evaluation of DNA Damage in Patients with Head and Neck Carcinoma Receiving Radiotherapy

Background:Head and neck cancers account for about 30% of all cancers in India. The incidence rates of HNSCC in India are30/1, 00,000 for males and 10/1, 00,000 for females. The commonly used treatment modalities include surgery, chemotherapy and radiotherapy. Studies conducted in different types of cancers showed that there is anincreased primary DNA damage even before the commencement of treatment in cancer patients.The treatment modality will further induce DNA damage in addition to the already existing DNA damage.In normal healthy people, DNA damage is effectively repaired. However, in patients with carcinoma, chemo-radiation induced DNA damage is not repaired so effectively. Consequently, there is a high risk of secondary carcinoma by unrepaired damaged DNA.Methodology:In this study, the degree of DNA damage is assessed by comet assay technique in patients with head and neck carcinoma receiving radiotherapy and had complete regression of tumor following radiotherapy. The degree of DNA damage is compared according to the age, gender and associated risk factors of the patients.Results:The comet length parameter of post-RT sample is increased when compared to baseline sample. The head diameter parameter of post-RT sample is increased when compared to baseline sample. The percentage of DNA in head parameter of post-RT sample is decreased when compared to baseline sample. The tail length parameter of post-RT sample is increased when compared to baseline sample. All these findings are indicative of DNA damage following radiotherapy. Consequently, there is a high risk of secondary carcinoma by unrepaired damaged DNA.Conclusion:Patients with locally advanced head and neck carcinoma with complete tumor response following radiotherapy showed a sequential increase in the DNA damage. The co-existing risk factors and old age may increase the baseline DNA damage in the patients with head and neck cancers.

Changes in ctDNA levels after MIBG therapy in patients with relapsed or refractory neuroblastoma.

10012 Background: Circulating tumor DNA (ctDNA) is detectable in children with neuroblastoma. Less is known about how levels change during treatment and the implications of these changes. We evaluated ctDNA pre- and post- 131I-metaiodobenzylguanidine (MIBG) therapy. Methods: We utilized plasma samples from NANT11-01 (NCT02035137), a multi-center, open label, randomized phase II clinical trial evaluating MIBG with or without radiation sensitizers for patients with relapsed or refractory neuroblastoma. Plasma was collected at Baseline prior to MIBG, 72 hours (Hr72), 96 hours (Hr96), 15 days after MIBG (D15), and prior to a second course among patients without progression who received a second course (C2). Samples were analyzed for percent ctDNA levels using ultra-low passage whole genome sequencing. We evaluated associations between ctDNA findings with baseline disease measures of percent involvement in bone marrow, Curie score, and RECIST disease sum of diameters as well as overall response by NANT Response Criteria v1.2 (complete response or partial response coded as responders). Results: Eighty-four patients had a baseline sample and were included in this analysis. Of the 37 patients (44%) with detectable ctDNA at baseline, the median ctDNA level was 32% (range 3.9-91%). Baseline ctDNA levels showed a significant positive correlation with percent involvement in bone marrow (r=0.37; p=0.0004) and Curie score (r=0.26; p = 0.018), but not RECIST sum of diameters for soft tissue sites (r=0.065; p=0.56). Following therapy, the proportions of patients with detectable ctDNA were: Hr72 47% (34/73; median level 28%); Hr96 50% (26/52; median 28%); D15 33% (7/21; median 4%); and C2 14% (3/21; median 50%). Rate of ctDNA detection was similar between responders and non-responders at baseline, Hr72, and Hr96, but lower among responders at D15 and C2 (Table). Among the 21 patients with C2 data, ctDNA levels were either undetectable (n=18) or lower than Cycle 1 Baseline (n=3). Among patients with detectable baseline ctDNA, the median relative ctDNA level at Hr72 (Hr72 ctDNA/baseline ctDNA) for non-responders was 0.87 (n=24) vs. 1.16 for responders (n=7). In contrast, the median relative ctDNA level at C2 for non-responders was 0.56 (n=4) vs. 0 for responders (n=4). Conclusions: ctDNA is detectable in a substantial proportion of patients with relapsed / refractory neuroblastoma, with levels correlated with conventional measures of disease burden. Following MIBG therapy, early timepoints (Hr72 and Hr96) are less informative, whereas ctDNA becomes undetectable at D15 and C2 more commonly in patients with clinical response.[Table: see text]

Facilitators and Barriers to Take Up Clinician-Collected and Self-Collected HPV Tests among Chinese Men Who Have Sex with Men

Regular tests for human papillomavirus (HPV) and early treatment could represent an important strategy for preventing anal cancers among men who have sex with men (MSM). This study investigated facilitators and barriers to take up clinician-collected and self-collected HPV tests among Chinese MSM. This study was based on the baseline sample of a longitudinal study promoting HPV vaccination among 350 Chinese MSM who had never received an HPV vaccination. The baseline survey was conducted from August 2019 to April 2020. The prevalence of any HPV tests uptake in lifetime was 19.1%; 4.9% had HPV infection in anus, genital, oral cavity, and other places. Among the participants, 20% and 76.8% intended to take up self-financed and free clinician-collected HPV tests, and 76.8% intended to use free self-collected HPV tests. After adjusting for significant background characteristics, perceived risk of HPV infection, and perceived benefits, barriers, cue to action, and self-efficacy related to HPV tests in general and/or specific to self-collected HPV tests were associated with behavioral intention to take up free clinician-collected and/or self-collected HPV tests. Less than 20% of Chinese MSM reported HPV tests uptake. Modifying perceptions related to HPV tests may be useful to increase HPV tests coverage in this group.

Use of Benzodiazepines in Patients With Bipolar Disorder

BackgroundBenzodiazepines (BZDs) are widely used in patients with bipolar disorder. The aim of this study was to determine chronic use of BZDs in patients with a first bipolar episode and the association between its use and cognition.MethodsA prospective longitudinal study was conducted in a cohort of 63 patients under 40 years old with a first manic or mixed episode. The percentage of patients taking BZDs in the baseline sample was evaluated at 6 months and for the next 3 years. Cognitive functioning was compared between patients with chronic BDZ use and those who did not use them. A linear regression model adjusted for potential confounding variables such as age and education level were used.ResultsJust over half the sample (55.6%; n = 35) took BZD at the start of the study. At 6 months, this percentage decreased to 34.9% (n = 22) and to 14.3% (n = 9) at 3 years of follow-up. Patients who took BZD chronically had worse outcomes in overall attention. These differences remained significant when controlled for the variables age and education level (B -0.462, p = 0.046, 95% CI: - 0.914 - 0.009).ConclusionsChronic administration of BZD occurs in a small percentage of bipolar patients at disease onset, and is associated with decreased attention. These side effects should be followed up.