3,525 research outputs found
Ultramicrobacteria Genome Database Project
Ultramicrobacteria (UMB) are a largely uncultured, globally abundant, and metabolically active group of bacteria. UMB have cell diameters ≤0.3μm, cell volumes ≤0.1 μm3, and small streamlined genomes. Recent findings indicate that UMB aid in bioremediation and nutrient cycling, but future investigations and comprehension of current findings are skewed by highly variable nomenclature and a lack of databases for functional, genomic, geochemical, or spatial data specific to candidate UMB. We aim to develop a user-friendly open-access database of various UMB candidates linked to an open-access online map where researchers can gather genomic, spatial, and geochemical data. Our comprehensive review of literature and genomic databases revealed several mis-identified UMB candidates, unique highly-conserved fermentation pathways, and novel membrane proteins. We are actively updating this resource and working to link this database to the K-base bioinformatics platform on the Oak Ridge National Laboratory Supercomputer. This database is one of the first steps towards further investigations of the function, structure, and potential biotechnical applications of UMB
A systematic review of machine learning models for management, prediction and classification of ARDS
Aim: Acute respiratory distress syndrome or ARDS is an acute, severe form of respiratory failure characterised by poor oxygenation and bilateral pulmonary infiltrates. Advancements in signal processing and machine learning have led to promising solutions for classification, event detection and predictive models in the management of ARDS. Method: In this review, we provide systematic description of different studies in the application of Machine Learning (ML) and artificial intelligence for management, prediction, and classification of ARDS. We searched the following databases: Google Scholar, PubMed, and EBSCO from 2009 to 2023. A total of 243 studies was screened, in which, 52 studies were included for review and analysis. We integrated knowledge of previous work providing the state of art and overview of explainable decision models in machine learning and have identified areas for future research. Results: Gradient boosting is the most common and successful method utilised in 12 (23.1%) of the studies. Due to limitation of data size available, neural network and its variation is used by only 8 (15.4%) studies. Whilst all studies used cross validating technique or separated database for validation, only 1 study validated the model with clinician input. Explainability methods were presented in 15 (28.8%) of studies with the most common method is feature importance which used 14 times. Conclusion: For databases of 5000 or fewer samples, extreme gradient boosting has the highest probability of success. A large, multi-region, multi centre database is required to reduce bias and take advantage of neural network method. A framework for validating with and explaining ML model to clinicians involved in the management of ARDS would be very helpful for development and deployment of the ML model
Human prostate sphere-forming cells represent a subset of basal epithelial cells capable of glandular regeneration in vivo.
BackgroundProstate stem/progenitor cells function in glandular development and maintenance. They may be targets for tumor initiation, so characterization of these cells may have therapeutic implications. Cells from dissociated tissues that form spheres in vitro often represent stem/progenitor cells. A subset of human prostate cells that form prostaspheres were evaluated for self-renewal and tissue regeneration capability in the present study.MethodsProstaspheres were generated from 59 prostatectomy specimens. Lineage marker expression and TMPRSS-ERG status was determined via immunohistochemistry and fluorescence in situ hybridization (FISH). Subpopulations of prostate epithelial cells were isolated by cell sorting and interrogated for sphere-forming activity. Tissue regeneration potential was assessed by combining sphere-forming cells with rat urogenital sinus mesenchyme (rUGSM) subcutaneously in immunocompromised mice.ResultsProstate tissue specimens were heterogeneous, containing both benign and malignant (Gleason 3-5) glands. TMPRSS-ERG fusion was found in approximately 70% of cancers examined. Prostaspheres developed from single cells at a variable rate (0.5-4%) and could be serially passaged. A basal phenotype (CD44+CD49f+CK5+p63+CK8-AR-PSA-) was observed among sphere-forming cells. Subpopulations of prostate cells expressing tumor-associated calcium signal transducer 2 (Trop2), CD44, and CD49f preferentially formed spheres. In vivo implantation of sphere-forming cells and rUGSM regenerated tubular structures containing discreet basal and luminal layers. The TMPRSS-ERG fusion was absent in prostaspheres derived from fusion-positive tumor tissue, suggesting a survival/growth advantage of benign prostate epithelial cells.ConclusionHuman prostate sphere-forming cells self-renew, have tissue regeneration capability, and represent a subpopulation of basal cells
A tidal lung simulation to quantify lung heterogeneity with the Inspired Sinewave Test
We have created a lung simulation to quantify lung heterogeneity from the
results of the inspired sinewave test (IST). The IST is a lung function test
that is non-invasive, non-ionising and does not require patients' cooperation.
A tidal lung simulation is developed to assess this test and also a method is
proposed to calculate lung heterogeneity from IST results. A sensitivity
analysis based on the Morris method and linear regression were applied to
verify and to validate the simulation. Additionally, simulated emphysema and
pulmonary embolism conditions were created using the simulation to assess the
ability of the IST to identify these conditions. Experimental data from five
pigs (pre-injured vs injured) were used for validation. This paper contributes
to the development of the IST. Firstly, our sensitivity analysis reveals that
the IST is highly accurate with an underestimation of about 5% of the simulated
values. Sensitivity analysis suggested that both instability in tidal volume
and extreme expiratory flow coefficients during the test cause random errors in
the IST results. Secondly, the ratios of IST results obtained at two tracer gas
oscillation frequencies can identify lung heterogeneity (ELV60/ELV180 and
Qp60/Qp180). There was dissimilarity between simulated emphysema and pulmonary
embolism (p < 0:0001). In the animal model, the control group had ELV60/ELV180
= 0.58 compared with 0.39 in injured animals (p < 0.0001)
Redundant Function of REV-ERBα and β and Non-Essential Role for Bmal1 Cycling in Transcriptional Regulation of Intracellular Circadian Rhythms
The mammalian circadian clockwork is composed of a core PER/CRY feedback loop and additional interlocking loops. In particular, the ROR/REV/Bmal1 loop, consisting of ROR activators and REV-ERB repressors that regulate Bmal1 expression, is thought to “stabilize” core clock function. However, due to functional redundancy and pleiotropic effects of gene deletions, the role of the ROR/REV/Bmal1 loop has not been accurately defined. In this study, we examined cell-autonomous circadian oscillations using combined gene knockout and RNA interference and demonstrated that REV-ERBα and β are functionally redundant and are required for rhythmic Bmal1 expression. In contrast, the RORs contribute to Bmal1 amplitude but are dispensable for Bmal1 rhythm. We provide direct in vivo genetic evidence that the REV-ERBs also participate in combinatorial regulation of Cry1 and Rorc expression, leading to their phase-delay relative to Rev-erbα. Thus, the REV-ERBs play a more prominent role than the RORs in the basic clock mechanism. The cellular genetic approach permitted testing of the robustness of the intracellular core clock function. We showed that cells deficient in both REV-ERBα and β function, or those expressing constitutive BMAL1, were still able to generate and maintain normal Per2 rhythmicity. Our findings thus underscore the resilience of the intracellular clock mechanism and provide important insights into the transcriptional topologies underlying the circadian clock. Since REV-ERB function and Bmal1 mRNA/protein cycling are not necessary for basic clock function, we propose that the major role of the ROR/REV/Bmal1 loop and its constituents is to control rhythmic transcription of clock output genes
Maternal stressful life events during the periconceptional period and orofacial clefts:a systematic review and meta-analysis
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