Publications by authors named "Aritra Chattopadhyay"

Biofilm-associated infections arising from antibiotic-resistant bacteria pose a critical challenge to global health. We report the generation of a library of cationic conjugated poly(phenylene ethynylene) (PPE) polymers featuring trimethylammonium terminated sidechains with tunable hydrophobicity. Screening of the library identified an amphiphilic polymer with a C hydrophobic spacer as the polymer with the highest antimicrobial efficacy against biofilms in the dark with excellent selectivity.

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Cell state transitions are fundamental in biology, determining how cells respond to environmental stimuli and adapt to diseases and treatments. Cell surface-based sensing of geno/phenotypes is a versatile approach for distinguishing different cell types and states. Array-based biosensors can provide a highly sensitive platform for distinguishing cells based on the differential interactions of each sensing element with cell surface components.

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Opportunistic bacterial pathogens can evade the immune response by residing and reproducing within host immune cells, including macrophages. These intracellular infections provide reservoirs for pathogens that enhance the progression of infections and inhibit therapeutic strategies. Current sensing strategies for intracellular infections generally use immunosensing of specific biomarkers on the cell surface or polymerase chain reaction (PCR) of the corresponding nucleic acids, making detection difficult, time-consuming, and challenging to generalize.

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Objectives: Fatty atrophy and fatty infiltration have been considered as limiting factors for rotator cuff repair. The metabolic activity of the muscle can be measured noninvasively by PET. In our study, we aim to compare the metabolic activity between the shoulders with rotator cuff tears and normal shoulders.

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Intracellular pathogenic bacteria use immune cells as hosts for bacterial replication and reinfection, leading to challenging systemic infections including peritonitis. The spread of multidrug-resistant (MDR) bacteria and the added barrier presented by host cell internalization limit the efficacy of standard antibiotic therapies for treating intracellular infections. We present a non-antibiotic strategy to treat intracellular infections.

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Integration of antimicrobial polymeric nanoparticles into hydrogel materials presents a promising strategy to address multidrug-resistant biofilm infections. Here we report an injectable hydrogel loaded with engineered cationic antimicrobial polymeric nanoparticles (PNPs) for the effective topical treatment of severe wound biofilm infections. The PNPs demonstrated biofilm penetration and disruption, resulting in the eradication of resistant and persister cells that reside within the biofilm.

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Bioorthogonal catalysis mediated by transition metal catalysts (TMCs) provides controlled activation of prodrugs through chemical reactions that do not interfere with cellular bioprocesses. The direct use of 'naked' TMCs in biological environments can have issues of solubility, deactivation, and toxicity. Here, we demonstrate the design and application of a biodegradable nanoemulsion-based scaffold stabilized by a cationic polymer that encapsulates a palladium-based TMC, generating bioorthogonal nanocatalyst "polyzymes".

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Macrophages are key components of the innate immune system that have essential functions in physiological processes and diseases. The phenotypic plasticity of macrophages allows cells to be polarized into a multidimensional spectrum of phenotypes, broadly classed as pro-inflammatory (M1) and anti-inflammatory (M2) states. Repolarization of M1 to M2 phenotypes alters the immune response to ameliorate autoimmune and inflammation-associated diseases.

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Multidrug resistance (MDR) in bacteria is a critical global health challenge that is exacerbated by the ability of bacteria to form biofilms. We report a combination therapy for biofilm infections that integrates silver nanoclusters (AgNCs) into polymeric biodegradable nanoemulsions (BNEs) incorporating eugenol. These Ag-BNEs demonstrated synergistic antimicrobial activity between the AgNCs and the BNEs.

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The rapid detection of proteins is very important in the early diagnosis of diseases. Gold nanoparticles (AuNPs) can be engineered to bind biomolecules efficiently and differentially. Cross-reactive sensor arrays have high sensitivity for sensing proteins using differential interactions between sensor elements and bioanalytes.

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Infections after arthroscopic procedures are rare. Infection due to fungal organisms is rarer and difficult to diagnose due to its insidious nature and chronic presentation but when neglected has devastating consequences. We present a 23-year-old immunocompetent adult post-arthroscopic meniscal repair with fungal surgical site infection.

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Hallux valgus is a common forefoot deformity characterized by medial deviation of the first metatarsal and lateral deviation of the hallux. More than 150 procedures have been described for the hallux valgus deformity with no proven superiority of one over the other. The initial osteotomies are open, and with the advent of power and micro instruments, the osteotomies were manageable via mini incisions and percutaneous procedures.

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Cell surface glycans serve fundamental roles in many biological processes, including cell-cell interaction, pathogen infection, and cancer metastasis. Cancer cell surface have alternative glycosylation to healthy cells, making these changes useful hallmarks of cancer. However, the diversity of glycan structures makes glycosylation profiling very challenging, with glycan 'fingerprints' providing an important tool for assessing cell state.

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Identification of Plasmodium-resistance genes in malaria vectors remains an elusive goal despite the recent availability of high-quality genomes of several mosquito vectors. Anopheles stephensi, with its three distinctly-identifiable forms at the egg stage, correlating with varying vector competence, offers an ideal species to discover functional mosquito genes implicated in Plasmodium resistance. Recently, the genomes of several strains of An.

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Bacterial biofilms are a major healthcare concern resulting in refractory conditions such as chronic wounds, implant infections and failure, and multidrug-resistant infections. Aggressive and invasive strategies are employed to cure biofilm infections but are prone to long and expensive treatments, adverse side-effects, and low patient compliance. Recent strategies such as ultrasound-based therapies and antimicrobial nanomaterials have shown some promise in the effective eradication of biofilms.

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Antibiotic resistance presents a critical threat to public health, necessitating the rapid development of novel antibiotics and an appropriate choice of therapeutics to combat refractory bacterial infections. Here, we report a high-throughput polymer-based sensor platform that rapidly (30 min) profiles mechanisms of antibiotic activity. The sensor array features three fluorophore-conjugated polymers that can detect subtle antibiotic-induced phenotypic changes on bacterial surfaces, generating distinct mechanism-based fluorescence patterns.

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Wound biofilm infections caused by multidrug-resistant (MDR) bacteria constitute a major threat to public health; acquired resistance combined with resistance associated with the biofilm phenotype makes combatting these infections challenging. Biodegradable polymeric nanoemulsions that encapsulate two hydrophobic antimicrobial agents (eugenol and triclosan) (TE-BNEs) as a strategy to combat chronic wound infections are reported here. The cationic nanoemulsions efficiently penetrate and accumulate in biofilms, synergistically eradicating MDR bacterial biofilms, including persister cells.

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Synthetic chemicals are widely used in food, agriculture, and medicine, making chemical safety assessments necessary for environmental exposure. In addition, the rapid determination of chemical drug efficacy and safety is a key step in therapeutic discoveries. Cell-based screening methods are non-invasive as compared with animal studies.

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Environmental agents can induce cellular responses at concentrations far below the limits of detection for current viability and biomarker-based cell sensing platforms. Hypothesis-free cell sensor platforms can be engineered to maximize sensitivity to phenotypic changes, providing a tool for lowering the threshold for detecting cellular changes. Pesticides are one of the most prevalent sources of chemical exposure due to their use in food and agriculture fields.

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Biofilm infections are a global public health threat, necessitating new treatment strategies. Biofilm formation also contributes to the development and spread of multidrug-resistant (MDR) bacterial strains. Biofilm-associated chronic infections typically involve colonization by more than one bacterial species.

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Macrophages are plastic cells of the innate immune system that perform a wide range of immune- and homeostasis-related functions. Due to their plasticity, macrophages can polarize into a spectrum of activated phenotypes. Rapid identification of macrophage polarization states provides valuable information for drug discovery, toxicological screening, and immunotherapy evaluation.

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Infections caused by multidrug-resistant (MDR) bacteria present an emerging global health crisis, and the threat is intensified by the involvement of biofilms. Some biofilm infections involve more than one species; this can further challenge treatment using traditional antibiotics. Nanomaterials are being developed as alternative therapeutics to traditional antibiotics; here we report biodegradable polymer-stabilized oil-in-water nanosponges (BNS) and show their activity against dual-species bacterial biofilms.

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Industrial use of nanomaterials is rapidly increasing, making the effects of these materials on the environment and human health of critical concern. Standard nanotoxicity evaluation methods rely on detecting cell death or major dysfunction and will miss early signs of toxicity. In this work, the use of rapid and sensitive nanosensors that can efficiently detect subtle phenotypic changes on the cell surface following nanomaterial exposure is reported.

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