597 research outputs found
Plasma microRNA levels following resection of metastatic melanoma
Melanoma remains the leading cause of skin cancer–related deaths. Surgical resection and adjuvant therapies can result in disease-free intervals for stage III and stage IV disease; however, recurrence is common. Understanding microRNA (miR) dynamics following surgical resection of melanomas is critical to accurately interpret miR changes suggestive of melanoma recurrence. Plasma of 6 patients with stage III (n = 2) and stage IV (n = 4) melanoma was evaluated using the NanoString platform to determine pre- and postsurgical miR expression profiles, enabling analysis of more than 800 miRs simultaneously in 12 samples. Principal component analysis detected underlying patterns of miR expression between pre- vs postsurgical patients. Group A contained 3 of 4 patients with stage IV disease (pre- and postsurgical samples) and 2 patients with stage III disease (postsurgical samples only). The corresponding preoperative samples to both individuals with stage III disease were contained in group B along with 1 individual with stage IV disease (pre- and postsurgical samples). Group A was distinguished from group B by statistically significant analysis of variance changes in miR expression ( P < .0001). This analysis revealed that group A vs group B had downregulation of let-7b-5p, miR-520f, miR-720, miR-4454, miR-21-5p, miR-22-3p, miR-151a-3p, miR-378e, and miR-1283 and upregulation of miR-126-3p, miR-223-3p, miR-451a, let-7a-5p, let-7g-5p, miR-15b-5p, miR-16-5p, miR-20a-5p, miR-20b-5p, miR-23a-3p, miR-26a-5p, miR-106a-5p, miR-17-5p, miR-130a-3p, miR-142-3p, miR-150-5p, miR-191-5p, miR-199a-3p, miR-199b-3p, and miR-1976. Changes in miR expression were not readily evident in individuals with distant metastatic disease (stage IV) as these individuals may have prolonged inflammatory responses. Thus, inflammatory-driven miRs coinciding with tumor-derived miRs can blunt anticipated changes in expression profiles following surgical resection
Insulin detemir offers improved glycemic control compared with NPH insulin in people with type 1 diabetes - A randomized clinical trial
OBJECTIVE—Insulin detemir is a soluble long-acting basal insulin analog designed to overcome the limitations of conventional basal insulin formulations. Accordingly, insulin detemir has been compared with NPH insulin with respect to glycemic control (HbA1c, prebreakfast glucose levels and variability, and hypoglycemia) and timing of administration. RESEARCH DESIGN AND METHODS—People with type 1 diabetes (n = 408) were randomized in an open-label, parallel-group trial of 16-week treatment duration using either insulin detemir or NPH insulin. Insulin detemir was administered twice daily using two different regimens, either before breakfast and at bedtime (IDetmorn+bed) or at a 12-h interval (IDet12h). NPH insulin was administered before breakfast and at bedtime. Mealtime insulin was given as the rapid-acting insulin analog insulin aspart. RESULTS—With both insulin detemir groups, clinic fasting plasma glucose was lower than with NPH insulin (IDet12h vs. NPH, −1.5 mmol/l [95% CI −2.51 to −0.48], P = 0.004; IDetmorn+bed vs. NPH, −2.3 mmol/l (−3.32 to −1.29), P < 0.001), as was self-measured prebreakfast plasma glucose (P = 0.006 and P = 0.004, respectively). The risk of minor hypoglycemia was lower in both insulin detemir groups (25%, P = 0.046; 32%, P = 0.002; respectively) compared with NPH insulin in the last 12 weeks of treatment, this being mainly attributable to a 53% reduction in nocturnal hypoglycemia in the IDetmorn+bed group (P < 0.001). Although HbA1c for each insulin detemir group was not different from the NPH group, HbA1c for the pooled insulin detemir groups was significantly lower than for the NPH group (mean difference −0.18% [−0.34 to −0.02], P = 0.027). Within-person between-day variation in self-measured prebreakfast plasma glucose was lower for both detemir groups (both P < 0.001). The NPH group gained weight during the study, but there was no change in weight in either of the insulin detemir groups (IDet12h vs. NPH, −0.8 kg [−1.44 to −0.24], P = 0.006; IDetmorn+bed vs. NPH, −0.6 kg [−1.23 to −0.03], P = 0.040). CONCLUSIONS—Overall glycemic control with insulin detemir was improved compared with NPH insulin. The data provide a basis for tailoring the timing of administration of insulin detemir to the individual person’s needs
Clinically Actionable Hypercholesterolemia and Hypertriglyceridemia in Children with Nonalcoholic Fatty Liver Disease
OBJECTIVE:
To determine the percentage of children with nonalcoholic fatty liver disease (NAFLD) in whom intervention for low-density lipoprotein cholesterol or triglycerides was indicated based on National Heart, Lung, and Blood Institute guidelines.
STUDY DESIGN:
This multicenter, longitudinal cohort study included children with NAFLD enrolled in the National Institute of Diabetes and Digestive and Kidney Diseases Nonalcoholic Steatohepatitis Clinical Research Network. Fasting lipid profiles were obtained at diagnosis. Standardized dietary recommendations were provided. After 1 year, lipid profiles were repeated and interpreted according to National Heart, Lung, and Blood Institute Expert Panel on Integrated Guidelines for Cardiovascular Health and Risk Reduction. Main outcomes were meeting criteria for clinically actionable dyslipidemia at baseline, and either achieving lipid goal at follow-up or meeting criteria for ongoing intervention.
RESULTS:
There were 585 participants, with a mean age of 12.8 years. The prevalence of children warranting intervention for low-density lipoprotein cholesterol at baseline was 14%. After 1 year of recommended dietary changes, 51% achieved goal low-density lipoprotein cholesterol, 27% qualified for enhanced dietary and lifestyle modifications, and 22% met criteria for pharmacologic intervention. Elevated triglycerides were more prevalent, with 51% meeting criteria for intervention. At 1 year, 25% achieved goal triglycerides with diet and lifestyle changes, 38% met criteria for advanced dietary modifications, and 37% qualified for antihyperlipidemic medications.
CONCLUSIONS:
More than one-half of children with NAFLD met intervention thresholds for dyslipidemia. Based on the burden of clinically relevant dyslipidemia, lipid screening in children with NAFLD is warranted. Clinicians caring for children with NAFLD should be familiar with lipid management
A protocol to evaluate RNA sequencing normalization methods
Background
RNA sequencing technologies have allowed researchers to gain a better understanding of how the transcriptome affects disease. However, sequencing technologies often unintentionally introduce experimental error into RNA sequencing data. To counteract this, normalization methods are standardly applied with the intent of reducing the non-biologically derived variability inherent in transcriptomic measurements. However, the comparative efficacy of the various normalization techniques has not been tested in a standardized manner. Here we propose tests that evaluate numerous normalization techniques and applied them to a large-scale standard data set. These tests comprise a protocol that allows researchers to measure the amount of non-biological variability which is present in any data set after normalization has been performed, a crucial step to assessing the biological validity of data following normalization.
Results
In this study we present two tests to assess the validity of normalization methods applied to a large-scale data set collected for systematic evaluation purposes. We tested various RNASeq normalization procedures and concluded that transcripts per million (TPM) was the best performing normalization method based on its preservation of biological signal as compared to the other methods tested.
Conclusion
Normalization is of vital importance to accurately interpret the results of genomic and transcriptomic experiments. More work, however, needs to be performed to optimize normalization methods for RNASeq data. The present effort helps pave the way for more systematic evaluations of normalization methods across different platforms. With our proposed schema researchers can evaluate their own or future normalization methods to further improve the field of RNASeq normalization
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Penalizing Health Care Providers: Enforcement or Exploitation?
The authors, health lawyers, recognize that "government plays an essential role in the oversight of health care." But they note an expansion in the amount and complexity of regulatory requirements, a trend toward more draconian penalties for violations, and greater resources, power and discretion for enforcement agencies. The articles calls for improving fairness through greater clarity of rules, specificity of requirements, substantive and procedural fairness, proportionality, support for compliance, and respect for providers
Examining heterogeneity in dementia using data-driven unsupervised clustering of cognitive profiles
Dementia is characterized by a decline in memory and thinking that is significant enough to impair function in activities of daily living. Patients seen in dementia specialty clinics are highly heterogenous with a variety of different symptoms that progress at different rates. Recent research has focused on finding data-driven subtypes for revealing new insights into dementia\u27s underlying heterogeneity, rather than assuming that the cohort is homogenous. However, current studies on dementia subtyping have the following limitations: (i) focusing on AD-related dementia only and not examining heterogeneity within dementia as a whole, (ii) using only cross-sectional baseline visit information for clustering and (iii) predominantly relying on expensive imaging biomarkers as features for clustering. In this study, we seek to overcome such limitations, using a data-driven unsupervised clustering algorithm named SillyPutty, in combination with hierarchical clustering on cognitive assessment scores to estimate subtypes within a real-world clinical dementia cohort. We use a longitudinal patient data set for our clustering analysis, instead of relying only on baseline visits, allowing us to explore the ongoing temporal relationship between subtypes and disease progression over time. Results showed that subtypes with very mild or mild dementia were more heterogenous in their cognitive profiles and risk of disease progression
Regulatory T Cells Expanded from Hiv-1-Infected Individuals Maintain Phenotype, Tcr Repertoire and Suppressive Capacity
While modulation of regulatory T cell (Treg) function and adoptive Treg transfer are being explored as therapeutic modalities in the context of autoimmune diseases, transplantation and cancer, their role in HIV-1 pathogenesis remains less well defined. Controversy persists regarding their beneficial or detrimental effects in HIV-1 disease, which warrants further detailed exploration. Our objectives were to investigate if functional CD4+ Tregs can be isolated and expanded from HIV-1-infected individuals for experimental or potential future therapeutic use and to determine phenotype and suppressive capacity of expanded Tregs from HIV-1 positive blood and tissue. Tregs and conventional T cell controls were isolated from blood and gut-associated lymphoid tissue of individuals with HIV-1 infection and healthy donors using flow-based cell-sorting. The phenotype of expanded Tregs was assessed by flow-cytometry and quantitative PCR. T-cell receptor ß-chain (TCR-β) repertoire diversity was investigated by deep sequencing. Flow-based T-cell proliferation and chromium release cytotoxicity assays were used to determine Treg suppressive function. Tregs from HIV-1 positive individuals, including infants, were successfully expanded from PBMC and GALT. Expanded Tregs expressed high levels of FOXP3, CTLA4, CD39 and HELIOS and exhibited a highly demethylated TSDR (Treg-specific demethylated region), characteristic of Treg lineage. The TCRß repertoire was maintained following Treg expansion and expanded Tregs remained highly suppressive in vitro. Our data demonstrate that Tregs can be expanded from blood and tissue compartments of HIV-1+ donors with preservation of Treg phenotype, function and TCR repertoire. These results are highly relevant for the investigation of potential future therapeutic use, as currently investigated for other disease states and hold great promise for detailed studies on the role of Tregs in HIV-1 infection.Elizabeth Glaser Pediatric AIDS Foundation (Pediatric HIV Vaccine Program Award MV-00-9-900-1429-0-00)Massachusetts General Hospital. Executive Committee on Research (MGH/ECOR Physician Scientist Development Award)National Institutes of Health (U.S.) (NIH NIAID (KO8 AI074405))National Institutes of Health (U.S.) (NIH NIAID AI074405-03S1)Massachusetts General Hospital (William F. Milton Fund)Harvard University. Center for AIDS Research (CFAR Scholar Award)Massachusetts General Hospital. Center for the Study Inflammatory Bowel Disease (P30DK043351)Harvard University. Center for AIDS Research (NIH funded program (5P30AI060354-09
Leveraging GPT-4 for identifying cancer phenotypes in electronic health records: A performance comparison between GPT-4, GPT-3.5-turbo, Flan-T5, Llama-3-8B, and spaCy\u27s rule-based and machine learning-based methods
OBJECTIVE: Accurately identifying clinical phenotypes from Electronic Health Records (EHRs) provides additional insights into patients\u27 health, especially when such information is unavailable in structured data. This study evaluates the application of OpenAI\u27s Generative Pre-trained Transformer (GPT)-4 model to identify clinical phenotypes from EHR text in non-small cell lung cancer (NSCLC) patients. The goal was to identify disease stages, treatments and progression utilizing GPT-4, and compare its performance against GPT-3.5-turbo, Flan-T5-xl, Flan-T5-xxl, Llama-3-8B, and 2 rule-based and machine learning-based methods, namely, scispaCy and medspaCy.
MATERIALS AND METHODS: Phenotypes such as initial cancer stage, initial treatment, evidence of cancer recurrence, and affected organs during recurrence were identified from 13 646 clinical notes for 63 NSCLC patients from Washington University in St. Louis, Missouri. The performance of the GPT-4 model is evaluated against GPT-3.5-turbo, Flan-T5-xxl, Flan-T5-xl, Llama-3-8B, medspaCy, and scispaCy by comparing precision, recall, and micro-F1 scores.
RESULTS: GPT-4 achieved higher F1 score, precision, and recall compared to Flan-T5-xl, Flan-T5-xxl, Llama-3-8B, medspaCy, and scispaCy\u27s models. GPT-3.5-turbo performed similarly to that of GPT-4. GPT, Flan-T5, and Llama models were not constrained by explicit rule requirements for contextual pattern recognition. spaCy models relied on predefined patterns, leading to their suboptimal performance.
DISCUSSION AND CONCLUSION: GPT-4 improves clinical phenotype identification due to its robust pre-training and remarkable pattern recognition capability on the embedded tokens. It demonstrates data-driven effectiveness even with limited context in the input. While rule-based models remain useful for some tasks, GPT models offer improved contextual understanding of the text, and robust clinical phenotype extraction
Electronic health record data quality assessment and tools: A systematic review
OBJECTIVE: We extended a 2013 literature review on electronic health record (EHR) data quality assessment approaches and tools to determine recent improvements or changes in EHR data quality assessment methodologies.
MATERIALS AND METHODS: We completed a systematic review of PubMed articles from 2013 to April 2023 that discussed the quality assessment of EHR data. We screened and reviewed papers for the dimensions and methods defined in the original 2013 manuscript. We categorized papers as data quality outcomes of interest, tools, or opinion pieces. We abstracted and defined additional themes and methods though an iterative review process.
RESULTS: We included 103 papers in the review, of which 73 were data quality outcomes of interest papers, 22 were tools, and 8 were opinion pieces. The most common dimension of data quality assessed was completeness, followed by correctness, concordance, plausibility, and currency. We abstracted conformance and bias as 2 additional dimensions of data quality and structural agreement as an additional methodology.
DISCUSSION: There has been an increase in EHR data quality assessment publications since the original 2013 review. Consistent dimensions of EHR data quality continue to be assessed across applications. Despite consistent patterns of assessment, there still does not exist a standard approach for assessing EHR data quality.
CONCLUSION: Guidelines are needed for EHR data quality assessment to improve the efficiency, transparency, comparability, and interoperability of data quality assessment. These guidelines must be both scalable and flexible. Automation could be helpful in generalizing this process
Evolution of fluid expulsion and concentrated hydrate zones across the southern Hikurangi subduction margin, New Zealand: An analysis from depth migrated seismic data
Identification of methane sources controlling hydrate distribution and concentrations in continental margins remains a major challenge in gas hydrate research. Lack of deep fluid samples and high quality regional scale seismic reflection data may lead to underestimation of the significance of fluid escape from subducting and compacting sediments in the global inventory of methane reaching the hydrate zone, the water column and the atmosphere. The distribution of concentrated hydrate zones in relation to focused fluid flow across the southern Hikurangi subduction margin was investigated using high quality, long offset (10 km streamer), pre-stack depth migrated multichannel seismic data. Analysis of low P wave velocity zones, bright-reverse polarity reflections and dim-amplitude anomalies reveals pathways for gas escape and zones of gas accumulation. The study shows the structural and stratigraphic settings of three main areas of concentrated hydrates: (1) the Opouawe Bank, dominated by focused periodic fluid input along thrust faults sustaining dynamic hydrate concentrations and gas chimneys development; (2) the frontal anticline, with a basal set of protothrusts controlling permeability for fluids from deeply buried and subducted sediments sustaining hydrate concentrations at the crest of the anticline; and (3) the Hikurangi Channel, with buried sand dominated channels hosting significant amounts of gas beneath the base of the hydrate zone. In sand dominated channels gas injection into the hydrate zone favors highly concentrated hydrate accumulations. The evolution of fluid expulsion controlling hydrate formation offshore southern Hikurangi is described in stages during which different methane sources (in situ, buried and thermogenic) have been dominant
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