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Biology subjects

Adhikari, G.

Publications and source records attributed to Adhikari, G..

4 recordsLinked to original sources

Development of a Novel Methyl Cellulose Hydrogel with Physiologically-Relevant Controlled Ethanol Release for Cervical Dysplasia Ablation

Cervical cancer is a leading cause of death in women in low- and middle-income countries (LMICs) and disproportionately affects women of minority populations in the US, primarily due to a lack of infrastructural support for specialized care. A promising treatment which meets accessibility requirements is ethyl cellulose (EC)-ethanol ablation--inducing necrotic cell death through application of ethanol to kill precancerous cells. While previous work focused on injecting EC-ethanol to ablate high-grade dysplasia (which can reach depths up to 5 mm below the tissue surface), low-grade dysplasia requires a different delivery method as it is much more superficial (reaching depths of only 1-3 mm). Here, we have developed a topical gel for local ethanol ablation of low-grade dysplasia with minimal damage to healthy cervical tissue. We investigated several gellants, including methyl cellulose (MC), EC, and Pluronic(R) F-127, to develop an ethanol gel that meets parameters for low cost and topical ease of use. Formulations with F-127 did not form gels with ethanol. Formulations with EC and MC were gel-forming. The MC-based formulations formed more uniform and stable gels that hold their own weight while still being spreadable at both room and body temperatures, key criterion for local cervical application. The optimal formulation contained 70% ethanol, 20% water, and 10% MC. One gram of this formulation represents approximately 5{cents} material cost, and formulated gels were stable for one week at least when stored at 4, 22, 30, and 37 {degrees}C. Additionally, the MC gel achieved localized ablation within 5 minutes after application to cervical cancer cells in-vitro. Taken together, we have developed a low-cost, efficacious, MC-based ethanol gel fit for translational testing to treat low-grade cervical dysplasia. This gel may provide a novel treatment option for women in LMICs, without causing major side effects or loss of healthy cervical tissue. Translational Impact StatementWe have developed a low-cost, efficacious, methyl cellulose-based ethanol gel fit for translational testing to topically treat low-grade cervical dysplasia. This addresses the need for a novel and accessible treatment option for women in low- and middle-income countries, which will not cause major side effects or loss of healthy cervical tissue. Ethics StatementAll work herein are the authors own original work. Authors have no conflicts of interest to disclose. Primary funding for the project was startup funds provided by the University of Maryland. All data available upon request.

bioengineering↗

Harnessing Lytic Phages for Biofilm Control in Carbapenem-Resistant Klebsiella pneumoniae Causing Urinary Tract Infection

BackgroundKlebsiella pneumoniae is a major opportunistic pathogen with rising multidrug resistance and biofilm-related infections. Molecular and phage characterization is crucial to understand resistance mechanisms and explore alternative therapies such as phage therapy. MethodsWe performed whole-genome sequencing and antibiotic susceptibility testing of hospital-isolated Klebsiella pneumoniae (KP6697). MLST, plasmid replicon analysis, and resistance gene identification were conducted using bioinformatics. Phage isolation, electron microscopy-based morphological and biofilm analysis, and evaluation of lytic activity, stability, and host range were performed. Phage genome sequencing and annotation identified functional genes. ResultsThe host strain Klebsiella pneumoniae (KP6697) was multidrug-resistant, exhibiting resistance to 18 of 22 tested antibiotics, and genome analysis identified ST16 with eight plasmid replicons and 23 resistance genes, including blaCTX-M-15, blaNDM-5, and blaOXA-181. Functional annotations revealed extensive metabolic versatility and a rich repertoire of genes for biofilm formation, quorum sensing, secretion systems, and stress response. A lytic phage, Phage_KP6697_Omshanti, was isolated and classified as a Caudoviricetes member with a 45.3kb genome encoding lysis, replication, and structural genes. It demonstrated short latency, high burst size, thermal and pH stability, and broad host range against CRKP and other MDR strains. Importantly, microscopy confirmed its ability to inhibit and degrade biofilms at multiple stages, highlighting strong therapeutic potential. ConclusionComprehensive analysis of carbapenem-resistant K. pneumoniae (KP6697) revealed multidrug resistance and strong biofilm formation. The lytic phage Phage_KP6697_Omshanti, with depolymerase and endolysin activity, disrupted biofilms, and its stability, high burst size, and genomic traits suggest potential as an anti-CRKP agent, especially with antibiotics IMPORTANCEKlebsiella pneumoniae is increasing multidrug resistance and robust biofilm formation pose severe clinical challenges, limiting treatment options. Understanding the molecular basis of its resistance and exploiting bacteriophages with strong biofilm-disrupting properties provide promising alternative therapeutic strategies. This study highlights the isolation and genomic characterization of a lytic phage with potent anti-biofilm activity against carbapenem-resistant K. pneumoniae, underscoring its potential in combating resistant infections.

microbiology↗

A fluorescent folding reporter uncovers myosin misfolding as a driver of Hypertrophic Cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is a fatal genetic disorder causing the thickening of ventricular walls in the heart muscle. While certain mutations in cardiac myosin deregulate ATPase activity, the pathology mechanism of most HCM mutations is not known. Here, by designing a fluorescent reporter to monitor myosin folding in cells, we uncovered a distinct class of HCM mutations that cause graded defects in myosin maturation. Using C. elegans as a disease model, we found that folding deficient HCM variants cause myofilament disruption, impaired motility, and reduced lifespan. Dietary restrictions resulted in a near-complete recovery from these detrimental defects by activating autophagy pathways through insulin/TOR signaling. In conclusion, our study identifies myosin misfolding as an important driver of HCM, revealing therapeutic opportunities to counteract muscle protein disorders.

cell biology↗

Development of a 3D in vitro human-sized model of cervical dysplasia to evaluate the delivery of ethyl cellulose-ethanol injection for the treatment of cervical dysplasia ablation

Cervical cancer, the second leading cause of cancer-related death for women worldwide, remains a preventable yet persistent disease that disproportionately affects women in low and middle-income countries (LMICs). While existing therapies for treating cervical dysplasia are effective, they are often inaccessible in LMICs. Ethanol ablation is an alternative low-cost, accessible therapy that we previously enhanced into an ethyl cellulose (EC)-ethanol gel formulation to improve efficacy. When seeking to evaluate EC-ethanol for cervical dysplasia, we found a paucity of relevant animal models. Thus, in this study, we developed a 3D in vitro model of cervical dysplasia featuring a central lesion of cervical cancer cells surrounded by fibroblasts and keratinocytes to enable the evaluation of EC-ethanol and other novel therapeutics. Our GelMA-based 3D model successfully captured the architectural complexity of cervical dysplasia, showcasing cell response and high viability. The GelMA hydrogel formulation (8.7% w/v) exhibited viscoelastic properties akin to human cervical tissue. Using micro-CT imaging, we assessed EC-ethanol injection deposition in the hydrogel, revealing retention of virtually the entire injected volume near the injection site. Finally, we evaluated the EC-ethanol injections efficacy in eliminating cervical cancer cells. The EC-ethanol injection led to a significant decrease in cancer cell viability while preserving healthy cells in the 3D in vitro model. Taken together, our in vitro model mirrored the architecture of cervical dysplasia and demonstrated the potential of EC-ethanol for localized treatment of cervical dysplasia.

bioengineering↗