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We previously reported that mutations in the thyroid hormone receptor (TR) surface that mediates dimer and heterodimer formation do not alter affinity for cognate hormone (triiodothyronine (T3)) yet dramatically enhance T3association and dissociation rates. This study aimed to show that TR oligomeric state influences binding and dissociation kinetics. We performed binding assays using marked hormone (125I-T3) and TRs expressed and purified by different methods. We find that T3associates with TRs with biphasic kinetics in solution; a rapid step (half-life ±0.1 h) followed by a slower second step (half-life ±5 h) and that purification of monomers suggests that biphasic kinetics are due to the presence of monomers and dimers in our preparations. In support of this idea, incubation of TR ligand binding domain monomers with corepressor peptide induces dimer formation and decreases association rates and T3binds to, and dissociates from, a TRβ mutant that only forms dimers (TRβD355R) with slow single-phase kinetics. In addition, heterodimer formation with retinoid X receptors also influences ligand binding kinetics. Together, these results suggest that the dimer/heterodimer surface is allosterically coupled to the hormone binding pocket and that different interactions at this surface exert different effects on ligand binding that may be relevant for TR actions in the cell. [ABSTRACT FROM AUTHOR]

Oil spill detection and mapping (OSPM) is an extremely relevant issue from a scientific point of view due to the environmental impact on coastal and marine ecosystems. In this study, we present a new approach to assess scientific literature for the past 50 years. In this sense, our study aims to perform a bibliometric and network analysis using a literature review on the application of OSPM to assess researchers and trends in this field of science. In methodological terms we used the Scopus base to search for articles in the literature, then we used bibliometric tools to access information and reveal quantifying patterns in this field of literature. Our results suggest that the detection of oil in the sea has undergone a great evolution in the last decades and there is a strong relationship between the technological evolution aimed at detection with the improvement of remote sensing data acquisition methods. The most relevant contributions in this field of science involved countries such as China, the United States, and Canada. We revealed aspects of great importance and interest in OSPM literature using a bibliometric and network approach to give a clear overview of this field's research trends. [ABSTRACT FROM AUTHOR]

Stage IV colorectal cancer treatment includes targeted therapy depending on RAS status. During disease progression, loss or gain of RAS mutations could happen, supporting the hypothesis of the evolutionary pressure of therapy. Circulating tumor DNA (ctDNA) are nucleic acids released to the bloodstream by the tumor during its development and may be detected by liquid biopsy. The Idylla© Biocartis, a fully automated real-time-PCR-based molecular diagnostic system, was used in a patient with metastatic colorectal cancer with a NRAS mutation in progression after several therapeutic lines. The ctDNA mutational analysis was performed and revealed the absence of mutations in the KRAS, NRAS, and BRAF genes. The patient started the third line of palliative chemotherapy with irinotecan + cetuximab and achieved a partial response for the first time. The authors describe a case in which liquid biopsy determined the higher progression-free survival achieved. [ABSTRACT FROM AUTHOR]

Type 1 Diabetes Mellitus (T1DM) can generate severe complications, such as Diabetic Kidney Disease (DKD) or Diabetic Nephropathy (DN), with it emerging as the leading cause of terminal (end-stage) renal disease all over the world. For T1DM, the clinical evaluation of DKD uses markers like the Glomerular Filtration Rate (GFR) and the Urinary Albumin Excretion (UAE). However, early diagnosis of DKD is still a challenge. For this reason, investigating molecular markers, such as microRNAs (miRNAs), offers a promising perspective to an early diagnosis, highlighting the stability and the ability to reflect incipient molecular manifestations. Thus, here we investigated four miRNAs (hsa-let-7i-5p, hsa-miR-143-3p, hsa-miR-501-3p, and hsa-miR-100-5p) regarding nephropathy in patients with T1DM, considering the albuminuria (micro and macro) as a standard to evaluate the groups. As a result, we found a reduced expression of miR-100-5p in patients with MIC, indicating a protective role in nephropathy. Beyond that, expression levels between the groups (Non vs. UAE) were not significant when comparing the miRNAs miR-501-3p and miR-143-3p. Finally, miR-143-3p and miR-100-5p were linked to some target genes such as AKT1, MMP13, and IGF1R, that are connected to signal pathways and cellular metabolism. [ABSTRACT FROM AUTHOR]

Background: Data on the prevalence of chronic pulmonary aspergillosis (CPA) in patients with active or cured tuberculosis (TB) are scarce, mainly due to diagnostic difficulties. The diagnosis of CPA is based on pulmonary symptoms and chest computed tomography (CT) scans and is considered confirmed when there is microbiological or serological evidence of Aspergillus spp. infection. Objectives: To estimate the prevalence of CPA in patients treated or undergoing treatment for PTB, seen in two referral hospitals in Mato Grosso do Sul, Brazil. Patients and Methods: A total of 193 consecutive patients who were treated or previously treated for pulmonary tuberculosis underwent prospective evaluation: (a) clinical evaluation; (b) chest CT scan; (c) sputum examination—culture for fungi and smears for direct mycology; (d) detection of anti‐Aspergillus fumigatus antibodies using an enzyme‐linked immunosorbent assay Platelia® test; and (e) anti‐Aspergillus spp. antibodies were assessed via a DID test. Results: The global prevalence of CPA was 10.9% (95% confidence interval, 7.2%–16.1%), but it increased with the time of TB diagnosis. The variables independently associated with CPA were previous pulmonary tuberculosis over 4 years ago and haemoptysis. Cavities, pleural thickening and the presence of a fungal ball were the most frequent tomographic findings in patients with CPA. Conclusions: The high prevalence observed and its increase over time suggest the need for continuous surveillance of CPA in patients with active or previous pulmonary tuberculosis and throughout life, with clinical, tomographic and serological evaluations (ELISA) for a timely diagnosis and a better prognosis. [ABSTRACT FROM AUTHOR]

The harvesting method is a challenge in microalgae production since it may influence the bioactivity of the product. This study aimed to evaluate if electroflocculation biomass harvesting altered the antioxidant properties and toxicity of methanol extracts from the marine microalgae Isochrysis galbana and Phaeodactylum tricornutum, compared with the traditional centrifugation approach. Analyses were based on the elimination of the 2,2-diphenyl-1-picryl-hydrazyl (DPPH) free radical by the active ingredients from the extracts, thin-layer chromatography (TLC), calculation of IC50, and extract toxicity. Phaeodactylum tricornutum had similar DPPH-reactive fractions (with antioxidant activity) different from the β-carotene control in the TLC for both biomass-separating methods, but its IC50 was 63% higher for electroflocculation (lower antioxidant activity). Bands with antioxidant activity were absent in the TCL of I. galbana (non-DPPH-reactive) for both harvesting methods. The extracts did not present mortality for the study with the Artemia salina model. Therefore, electroflocculation can produce up to 10 times more biomass without cytotoxicity output but may decrease the antioxidant potential of microalgae extracts. [ABSTRACT FROM AUTHOR]

The characterization of irregular patterns in images has become a focal point in numerous studies due to its relevance in various applications. In particular, images depicting natural phenomena exhibit intricate patterns with unique irregularities, such as self-similarity and scaling. The classification of these phenomena based on their patterns has been an ongoing endeavor within the field of complex systems. However, existing techniques for characterizing these complex phenomena typically assume isotropic variability patterns, which is not always feasible. To address these limitations, this paper introduces a novel algorithm, called the maximum angular multiscale entropy (MAMSE), based on the multiscale entropy method. The MAMSE algorithm overcomes the challenges posed by anisotropic fractal properties and is tested on synthetic images featuring both isotropic irregularities and anisotropic fractal properties. The experimental results reveal a new concept of angular self-similarity enabled by MAMSE, which proves instrumental in effectively distinguishing between groups of oil spill and low-wind conditions images. Comparative analysis with the two-dimensional multiscalar entropy algorithm demonstrates the superior performance and efficiency of MAMSE, yielding better and faster results. • Using MAMSE algorithm, we can observe how the isotropy of the image changes with the scale. • Angular self-similarity is not always observed in real images, as we will see for satellite images. • Fractal images show lower entropy values than the random images. • The MAMSE algorithm can be up to 102x faster when compared to two-dimensional multiscale entropy. [ABSTRACT FROM AUTHOR]