The murine metastatic microenvironment of experimental brain metastases of breast cancer differs by host age in vivo: a proteomic study.

Breast cancer in young patients is known to exhibit more aggressive biological behavior and is associated with a less favorable prognosis than the same disease in older patients, owing in part to an increased incidence of brain metastases. The mechanistic explanations behind these findings remain poorly understood. We recently reported that young mice, in comparison to older mice, developed significantly greater brain metastases in four mouse models of triple-negative and luminal B breast cancer. Here we have performed a quantitative mass spectrometry-based proteomic analysis to identify proteins potentially contributing to age-related disparities in the development of breast cancer brain metastases. Using a mouse hematogenous model of brain-tropic triple-negative breast cancer (MDA-MB-231BR), we harvested subpopulations of tumor metastases, the tumor-adjacent metastatic microenvironment, and uninvolved brain tissues via laser microdissection followed by quantitative proteomic analysis using high resolution mass spectrometry to characterize differentially abundant proteins potentially contributing to age-dependent rates of brain metastasis. Pathway analysis revealed significant alterations in signaling pathways, particularly in the metastatic microenvironment, modulating tumorigenesis, metabolic processes, inflammation, and neuronal signaling. Tenascin C (TNC) was significantly elevated in all laser microdissection (LMD) enriched compartments harvested from young mice relative to older hosts, which was validated and confirmed by immunoblot analysis of whole brain lysates. Additional in vitro studies including migration and wound-healing assays demonstrated TNC as a positive regulator of tumor cell migration. These results provide important new insights regarding microenvironmental factors, including TNC, as mechanisms contributing to the increased brain cancer metastatic phenotype observed in young breast cancer patients.

WGS-based screening of the co-chaperone protein DjlA-induced curved DNA binding protein A (CbpA) from a new multidrug-resistant zoonotic mastitis-causing Klebsiella pneumoniae strain: a novel molecular target of selective flavonoids.

The research aimed to establish a multidrug-resistant Klebsiella pneumoniae-induced genetic model for mastitis considering the alternative mechanisms of the DjlA-mediated CbpA protein regulation. The Whole Genome Sequencing of the newly isolated K. pneumoniae strain was conducted to annotate the frequently occurring antibiotic resistance and virulence factors following PCR and MALDI-TOF mass-spectrophotometry. Co-chaperon DjlA was identified and extracted via restriction digestion on PAGE. Based on the molecular string property analysis of different DnaJ and DnaK type genes, CbpA was identified to be regulated most by the DjlA protein during mastitis. Based on the quantum tunnel-cluster profiles, CbpA was modeled as a novel target for diversified biosynthetic, and chemosynthetic compounds. Pharmacokinetic and pharmacodynamic analyses were conducted to determine the maximal point-specificity of selective flavonoids in complexing with the CbpA macromolecule at molecular docking. The molecular dynamic simulation (100 ns) of each of the flavonoid-protein complexes was studied regarding the parameters RMSD, RMSF, Rg, SASA, MMGBSA, and intramolecular hydrogen bonds; where all of them resulted significantly. To ratify all the molecular dynamic simulation outputs, the potential stability of the flavonoids in complexing with CbpA can be remarked as Quercetin > Biochanin A > Kaempherol > Myricetin, which were all significant in comparison to the control Galangin. Finally, a comprehensive drug-gene interaction pathway for each of the flavonoids was developed to determine the simultaneous and quantitative-synergistic effects of different operons belonging to the DnaJ-type proteins on the metabolism of the tested pharmacophores in CbpA. Considering all the in vitro and in silico parameters, DjlA-mediated CbpA can be a novel target for the tested flavonoids as the potential therapeutics of mastitis as futuristic drugs.

Easy synthesis of PPy/TiO2/ZnO composites with superior photocatalytic performance, efficient supercapacitors and nitrite sensor.

The synthesis of Polypyrrole (PPy)/TiO2/ZnO composites involved a chemical oxidative polymerization process, wherein the addition of TiO2/ZnO was varied from 1 to 10 wt%. The composites' photocatalytic capabilities, supercapacitor performance, and potential use as a nitrite sensor were thoroughly assessed, alongside investigations into their photoluminescence (PL) and morphological characteristics. The strong interaction between TiO2/ZnO and PPy was confirmed using FTIR, UV-Vis, and PL spectroscopy techniques. The composites demonstrated aggregated and spherical-shaped morphological features investigated by FESEM. Such morphological structures of the composites were distinct from the TiO2/ZnO (rod-like) and similar to PPy structure (spherical). However, such composites showed dominating spherical-shaped morphology ensuring a diameter in the range of 50-200 nm. The PPy/TiO2/ZnO composites exhibited significantly enhanced photocatalytic efficiency in methylene blue (MB) removal, achieving a range of 88-93% compared to PPy alone, which only achieved 77.2% MB removal. The Cyclic Voltammetry (CV) data exhibited a promising hybrid supercapacitor performance of the composites with a high capacitance value, good energy density, as well as an excellent power density. The fabricated supercapacitor was capable of lightened up a single red 5 mm LED for a few minutes, indicating the commendable energy storage capacity. A newly developed PPy/TiO2/ZnO composite is potentially used to develop as a sensor probe for the detection of nitrite chemicals using the linear sweep voltammetry (LSV) technique in three electrodes system in room conditions. It is found an excellent sensor results in terms of sensitivity as well as detection limit and satisfactory results when validated with the real samples. These results offer novel insights into the fabrication of PPy/TiO2/ZnO photocatalysts for addressing organic waste treatment, while also presenting promising prospects for potential applications in supercapacitors and sensors.

Target-specificity of different amyrin subunits in impeding HCV influx mechanism inside the human cells considering the quantum tunnel profiles and molecular strings of the CD81 receptor: a combined in silico and in vivo study.

HCV is a hepatotropic RNA virus recognized for its frequent virulence and fatality worldwide. Despite many vaccine development programs underway, researchers are on a quest for natural bioactive compounds due to their multivalent efficiencies against viral infections, considering which the current research aimed to figure out the target-specificity and therapeutic potentiality of α, ß, and δ subunits of amyrin, as novel bioactive components against the HCV influx mechanism. Initially, the novelty of amyrin subunits was conducted from 203 pharmacophores, comparing their in-silico pharmacokinetic and pharmacodynamic profiles. Besides, the best active site of CD81 was determined following the quantum tunneling algorithm. The molecular dynamic simulation was conducted (100 ns) following the molecular docking steps to reveal the parameters- RMSD (Å); Cα; RMSF (Å); MolSA (Å2); Rg (nm); PSA (Å); SASA (Å2), and the MM-GBSA dG binding scores. Besides, molecular strings of CD81, along with the co-expressed genes, were classified, as responsible for encoding CD81-mediated protein clusters during HCV infection, resulting in the potentiality of amyrins as targeted prophylactics in HCV infection. Finally, in vivo profiling of the oxidative stress marker, liver-specific enzymes, and antioxidant markers was conducted in the DMN-induced mice model, where ß-amyrin scored the most significant values in all aspects.

Biochemical and structural characterization of analogs of MRE11 breast cancer-associated mutant F237C.

The MRE11-RAD50-NBS1 (MRN) protein complex plays a vital role in DNA double strand break sensing, signaling, and repair. Mutation in any component of this complex may lead to disease as disrupting DNA double strand break repair has the potential to cause translocations and loss of genomic information. Here, we have investigated an MRE11 mutation, F237C, identified in a breast cancer tumor. We found that the analogous mutant of Pyrococcus furiosus Mre11 diminishes both the exonuclease and endonuclease activities of Mre11 in vitro. Solution state NMR experiments show that this mutant causes structural changes in the DNA-bound Mre11 for both exo- and endonuclease substrates and causes the protein to become generally more rigid. Moreover, by comparing the NMR data for this cancer-associated mutant with two previously described Mre11 separation-of-nuclease function mutants, a potential allosteric network was detected within Mre11 that connects the active site to regions responsible for recognizing the DNA ends and for dimerization. Together, our data further highlight the dynamics required for Mre11 nuclease function and illuminate the presence of allostery within the enzyme.

Automatic identification of abnormal blood smear images using color and morphology variation of RBCS and central pallor.

The anatomy of red blood cells (RBCs) in blood smear images plays an important role in the detection of several diseases. The automated image-based technique is fast and accurate for the analysis of blood cells morphology that can save time of both pathologists as well as that of patients. In this paper, we propose a novel method which segment and identify varied RBCs in a given blood smear images. In the proposed method, the central pallor and whole cell information are used, after using color processing followed by double thresholding of blood smear images. The shape and size variances of cells are calculated for the identification of abnormalities in peripheral blood smear images. We used cross-validation accuracy weighted probabilistic ensemble (CAWPE). It is a heterogeneous ensembling technique of nearly equivalent classifiers produced on averagely significant better classifiers (regarding errors and probability estimates) as compared to a wide range of potential parent classifiers. The proposed method is tested on 3 sets of images. The sets of images were prepared in a local government hospital by expert pathologists. Each image set has varied photographic conditions. The method was found accurate in term of results, closer to the ground truth. The average accuracy of the proposed method is 97% for the segmentation of single cells and 96% for overlapped cells. The variance (σ2) of accuracy is 3.5 and the deviation (σ) is 1.87.

A Survey of Reported Disease-Related Mutations in the MRE11-RAD50-NBS1 Complex.

The MRE11-RAD50-NBS1 (MRN) protein complex is one of the primary vehicles for repairing DNA double strand breaks and maintaining the genomic stability within the cell. The role of the MRN complex to recognize and process DNA double-strand breaks as well as signal other damage response factors is critical for maintaining proper cellular function. Mutations in any one of the components of the MRN complex that effect function or expression of the repair machinery could be detrimental to the cell and may initiate and/or propagate disease. Here, we discuss, in a structural and biochemical context, mutations in each of the three MRN components that have been associated with diseases such as ataxia telangiectasia-like disorder (ATLD), Nijmegen breakage syndrome (NBS), NBS-like disorder (NBSLD) and certain types of cancers. Overall, deepening our understanding of disease-causing mutations of the MRN complex at the structural and biochemical level is foundational to the future aim of treating diseases associated with these aberrations.

Mutation of Conserved Mre11 Residues Alter Protein Dynamics to Separate Nuclease Functions.

Naked and protein-blocked DNA ends occur naturally during immune cell development, meiosis, and at telomeres as well as from aborted topoisomerase reactions, collapsed replication forks, and other stressors. Damaged DNA ends are dangerous in cells and if left unrepaired can lead to genomic rearrangement, loss of genetic information, and eventually cancer. Mre11 is part of the Mre11-Rad50-Nbs1 complex that recognizes DNA double-strand breaks and has exonuclease and endonuclease activities that help to initiate the repair processes to resolve these broken DNA ends. In fact, these activities are crucial for proper DNA damage repair pathway choice. Here, using Pyrococcus furiosus Mre11, we question how two Mre11 separation-of-function mutants, one previously described but the second first described here, maintain endonuclease activity in the absence of exonuclease activity. To start, we performed solution-state NMR experiments to assign the side-chain methyl groups of the 64-kDa Mre11 nuclease and capping domains, which allowed us to describe the structural differences between Mre11 bound to exo- and endonuclease substrates. Then, through biochemical and biophysical characterization, including NMR structural and dynamics studies, we compared the two mutants and determined that both affect the dynamic features and double-stranded DNA binding properties of Mre11, but in different ways. In total, our results illuminate the structural and dynamic landscape of Mre11 nuclease function.

Radar micro-Doppler signatures of drones and birds at K-band and W-band.

Due to the substantial increase in the number of affordable drones in the consumer market and their regrettable misuse, there is a need for efficient technology to detect drones in airspace. This paper presents the characteristic radar micro-Doppler properties of drones and birds. Drones and birds both induce micro-Doppler signatures due to their propeller blade rotation and wingbeats, respectively. These distinctive signatures can then be used to differentiate a drone from a bird, along with studying them separately. Here, experimental measurements of micro-Doppler signatures of different types of drones and birds are presented and discussed. The data have been collected using two radars operating at different frequencies; K-band (24 GHz) and W-band (94 GHz). Three different models of drones and four species of birds of varying sizes have been used for data collection. The results clearly demonstrate that a phase coherent radar system can retrieve highly reliable and distinctive micro-Doppler signatures of these flying targets, both at K-band and W-band. Comparison of the signatures obtained at the two frequencies indicates that the micro-Doppler return from the W-band radar has higher SNR. However, micro-Doppler features in the K-band radar returns also reveal the micro-motion characteristics of drones and birds very effectively.

A dynamic allosteric pathway underlies Rad50 ABC ATPase function in DNA repair.

The Mre11-Rad50 protein complex is an initial responder to sites of DNA double strand breaks. Many studies have shown that ATP binding to Rad50 causes global changes to the Mre11-Rad50 structure, which are important for DNA repair functions. Here we used methyl-based NMR spectroscopy on a series of mutants to describe a dynamic allosteric pathway within Rad50. Mutations result in changes in the side chain methyl group chemical environment that are correlated with altered nanosecond timescale dynamics. We also observe striking relationships between the magnitude of chemical shift perturbations and Rad50 and Mre11 activities. Together, these data suggest an equilibrium between a ground state and an "active" dimerization competent state of Rad50 that has locally altered structure and dynamics and is poised for ATP-induced dimerization and eventual ATP hydrolysis. Thus, this sparsely populated intermediate is critical for Mre11-Rad50-directed DNA double strand break repair.