Publications by authors named "Arpan De"

Article Synopsis
  • Understanding bacterial movement from human feces may help diagnose and treat inflammatory bowel disease.
  • The text outlines a method for conducting a microbial swarming assay to isolate and identify these bacteria using techniques like MALDI-TOF mass spectrometry and whole-genome sequencing.
  • It emphasizes the importance of validating results by repeating the swarming assay to confirm the observed behavior of the bacteria.
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The malignant brain cancer glioblastoma (GBM) contains groups of highly invasive cells that drive tumor progression as well as recurrence after surgery and chemotherapy. The molecular mechanisms that enable these GBM cells to exit the primary mass and disperse throughout the brain remain largely unknown. Here we report using human tumor specimens and primary spheroids from male and female patients that glial cell adhesion molecule (GlialCAM), which has normal roles in brain astrocytes and is mutated in the developmental brain disorder megalencephalic leukoencephalopathy with subcortical cysts (MLC), is differentially expressed in subpopulations of GBM cells.

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The development of sensing technologies and miniaturization allows for the development of smart systems with elevated sensing performance. Silicon-based hydrogen sensors have received a lot of attention due to its electrical conductivity and the mechanical endurance. With this motivation, we have proposed a two-terminal silicon-based device in a crossbar architecture as a hydrogen gas sensing platform.

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Deoxyribonucleic acid (DNA) has emerged as a promising building block for next-generation ultra-high density storage devices. Although DNA has high durability and extremely high density in nature, its potential as the basis of storage devices is currently hindered by limitations such as expensive and complex fabrication processes and time-consuming read-write operations. In this article, we propose the use of a DNA crossbar array architecture for an electrically readable read-only memory (DNA-ROM).

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The blood-brain barrier (BBB) is a vascular endothelial cell boundary that partitions the circulation from the central nervous system to promote normal brain health. We have a limited understanding of how the BBB is formed during development and maintained in adulthood. We used quantitative transcriptional profiling to investigate whether specific adhesion molecules are involved in BBB functions, with an emphasis on understanding how astrocytes interact with endothelial cells.

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Many species of bacteria change their morphology and behavior under external stresses. In this study, we report transient elongation and swimming motility of a novel Enterobacter sp. strain, SM1_HS2B, in liquid broth under a standard growth condition.

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The molecular mechanism of circadian clocks depends on transcription-translation feedback loops (TTFLs) that have known effects on key cellular processes. However, the distinct role of circadian TTFLs in mammalian stem cells and other less differentiated cells remains poorly understood. Neural stem cells (NSCs) of the brain generate neurons and glia postnatally but also may become cancer stem cells (CSCs), particularly in astrocytomas.

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In the developing mammalian brain, neuroepithelial cells interact with blood vessels to regulate angiogenesis, blood-brain barrier maturation and other key neurovascular functions. Genetic studies in mice have shown that neurovascular development is controlled, in part, by Itgb8, which encodes the neuroepithelial cell-expressed integrin β8 subunit. However, these studies have involved complete loss-of-function Itgb8 mutations, and have not discerned the relative roles for the β8 integrin extracellular matrix (ECM) binding region versus the intracellular signaling tail.

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In the mammalian brain, perivascular astrocytes (PAs) closely juxtapose blood vessels and are postulated to have important roles in the control of vascular physiology, including regulation of the blood-brain barrier (BBB). Deciphering specific functions for PAs in BBB biology, however, has been limited by the ability to distinguish these cells from other astrocyte populations. In order to characterize selective roles for PAs , a new mouse model has been generated in which the endogenous megalencephalic leukoencephalopathy with subcortical cysts 1 (Mlc1) gene drives expression of Cre fused to a mutated estrogen ligand-binding domain (Mlc1-T2A-CreERT2).

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We propose and investigate a biosensor based on a transparent dielectric-modulated dual-trench gate-engineered metal-oxide-semiconductor field-effect transistor (DM DT GE-MOSFET) for label-free detection of biomolecules with enhanced sensitivity and efficiency. Various sensing parameters such as the / ratio and the threshold voltage shift are evaluated as metrics to validate the proposed sensing device. Additionally, (the sensitivity) is also analyzed, considering both positively and negatively charged biomolecules.

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Background And Aims: Bacterial swarming, a collective movement on a surface, has rarely been associated with human pathophysiology. This study aims to define a role for bacterial swarmers in amelioration of intestinal stress.

Methods: We developed a polymicrobial plate agar assay to detect swarming and screened mice and humans with intestinal stress and inflammation.

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Cancer and circadian rhythms are linked in several ways, through immunomodulatory, neuroendocrine, and metabolic pathways. The circadian timing system consists of interacting circadian clocks in organs throughout the body that contain cells endowed with self-sustaining molecular circadian oscillations. Circadian rhythms are spontaneously generated by specific transcription and translation feedback cycles.

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Glioblastoma (GBM), or grade IV astrocytoma, is a malignant brain cancer that contains subpopulations of proliferative and invasive cells that coordinately drive primary tumor growth, progression, and recurrence after therapy. Here, we have analyzed functions for megalencephalic leukoencephalopathy with subcortical cysts 1 (Mlc1), an eight-transmembrane protein normally expressed in perivascular brain astrocyte end feet that is essential for neurovascular development and physiology, in the pathogenesis of GBM. We show that Mlc1 is expressed in human stem-like GBM cells (GSCs) and is linked to the development of primary and recurrent GBM.

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Epithelial-mesenchymal transition (EMT) is a key event preceding tumor cell metastasis that increases cell invasiveness and cancer stem cell (CSC) populations. Studies suggest that genes used in generating circadian rhythms also serve in regulating EMT. To test the role of circadian clocks in cellular EMT events two cancer cell lines were compared, one that has a well-established circadian clock, C6 from rat glioma, and one that does not, MCF-7 from human breast tumor.

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Background: The suprachiasmatic nucleus (SCN) of the mammalian hypothalamus contains the master circadian clock of the body and an unusually large number of cells expressing stem cell-related proteins. These seemingly undifferentiated cells may serve in entrainment of the SCN circadian clock to light cycles or allow it to undergo neural plasticity important for modifying its rhythmic output signals. These cells may also proliferate and differentiate into neurons or glia in response to episodic stimuli or developmental events requiring alterations in the SCN's control of physiology and behavior.

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Article Synopsis
  • - MecA is an adaptor protein essential for ClpC/P-mediated proteolysis, and its absence in the mutant TW416 resulted in altered cell characteristics, including mucoid colonies, growth in chains of swollen cells, and a reduced growth rate compared to the wild-type UA159.
  • - The TW416 mutant exhibited significantly impaired biofilm formation, which was linked to lower expression levels of key proteins such as glucosyltransferases GtfC and GtfB, as well as the adhesins P1 and WapA.
  • - Although TW416 had much lower cell wall phosphate levels, it displayed a higher signal intensity when analyzed for murein sacculi, suggesting that MecA might play additional roles
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Cells expressing proteins characteristic of stem cells and progenitor cells are present in the suprachiasmatic nucleus (SCN) of the adult mammalian hypothalamus. Any relationship between this distinctive feature and the master circadian clock of the SCN is unclear. Considering the lack of obvious neurogenesis in the adult SCN relative to the hippocampus and other structures that provide neurons and glia, it is possible that the SCN has partially differentiated cells that can provide neural circuit plasticity rather than ongoing neurogenesis.

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Our recent studies have shown that BrpA in Streptococcus mutans plays a critical role in cell envelope biogenesis, stress responses, and biofilm formation. In this study, a 10-species consortium was used to assess how BrpA deficiency influences the establishment, persistence, and competitiveness of S. mutans during growth in a community under conditions typical of the oral cavity.

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Streptococcus mutans, a dental caries causing odontopathogen, produces X-prolyl dipeptidyl peptidase (Sm-XPDAP, encoded by pepX), a serine protease known to have a nutritional role. Considering the potential of proteases as therapeutic targets in pathogens, this study was primarily aimed at investigating the role of Sm-XPDAP in contributing to virulence-related traits. Dipeptidyl peptidase (DPP IV), an XPDAP analogous enzyme found in mammalian tissues,is a well known therapeutic target in Type II diabetes.

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Like , lactobacilli are commonly isolated from carious sites, although their exact role in caries development remains unclear. This study used mixed-species models to analyze biofilm formation by major groups of oral lactobacilli, including ssp. , and .

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To evaluate the cariogenic properties of almond milk beverages, 6 almond milks, along with soy and whole bovine milk, were analyzed for their abilities to support Streptococcus mutans biofilm formation and acid production, and their capacity to buffer changes in pH. Biofilm formation by S. mutans was analyzed using an in vitro 96-well plate model and measured by crystal violet staining.

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is known to possess rhamnose-glucose polysaccharide (RGP), a major cell wall antigen. strains deficient in , encoding the first enzyme of the RGP biosynthesis pathway, were constructed by allelic exchange. The deficiency had no effect on growth rate but caused major defects in cell division and altered cell morphology.

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Ziziphus jujuba Mill., jujube, leaf infusions are popular bedtime beverages as they improve sleep by soothing the nerves. With the aim of providing further insights into the polyphenol content of jujube leaf infusion and their antioxidant activities, a 2,2-diphenyl-1-picrylhydrazyl (DPPH)-guided purification of the aqueous extract of Z.

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Our study focuses on the antimicrobial susceptibility, genotypic and phenotypic heterogeneity, and serotype classification of the isolated from type II diabetic patients (n = 25; age 42-68). Eighty-two percent of isolates were classified as serotype . No serotype was present.

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