Electro-antibacterial therapy (EAT) to enhance intracellular bacteria clearance in pancreatic cancer cells.

Intratumoral bacteria have been implicated in driving tumor progression, yet effective treatments to modulate the tumor microbiome remain limited. In this study, we investigate the use of electroporation in combination with metronidazole to enhance the clearance of intracellular Fusobacterium nucleatum within pancreatic cancer cells. We explore various parameters, including electric field strength, pulse width, and pulse number to assess the permeability of pancreatic cancer cells infected with F. nucleatum, compared to non-infected cells of the same type. We subsequently quantify the clearance of intracellular bacteria when these pulsing schemes are applied to a suspension of infected pancreatic cancer cells in the presence of metronidazole. Our results reveal distinct differences in cell permeability between infected and non-infected cells, identifying a unique biophysical marker for host cells infected with F. nucleatum. We demonstrate that the combinatorial use of electroporation and metronidazole significantly enhances the delivery of metronidazole into host cells, leading to more effective clearance of intracellular F. nucleatum compared to independent treatments; we term this novel approach Electro-Antibacterial Therapy (EAT). EAT holds promise as an innovative strategy for addressing intratumoral bacteria in pancreatic cancer, other malignancies, and potentially treatment-resistant infections, offering new avenues for therapeutic intervention.

High-Frequency Dielectrophoresis Reveals That Distinct Bio-Electric Signatures of Colorectal Cancer Cells Depend on Ploidy and Nuclear Volume.

Aneuploidy, or an incorrect chromosome number, is ubiquitous among cancers. Whole-genome duplication, resulting in tetraploidy, often occurs during the evolution of aneuploid tumors. Cancers that evolve through a tetraploid intermediate tend to be highly aneuploid and are associated with poor patient prognosis. The identification and enrichment of tetraploid cells from mixed populations is necessary to understand the role these cells play in cancer progression. Dielectrophoresis (DEP), a label-free electrokinetic technique, can distinguish cells based on their intracellular properties when stimulated above 10 MHz, but DEP has not been shown to distinguish tetraploid and/or aneuploid cancer cells from mixed tumor cell populations. Here, we used high-frequency DEP to distinguish cell subpopulations that differ in ploidy and nuclear size under flow conditions. We used impedance analysis to quantify the level of voltage decay at high frequencies and its impact on the DEP force acting on the cell. High-frequency DEP distinguished diploid cells from tetraploid clones due to their size and intracellular composition at frequencies above 40 MHz. Our findings demonstrate that high-frequency DEP can be a useful tool for identifying and distinguishing subpopulations with nuclear differences to determine their roles in disease progression.

Introducing electric field fabrication: A method of additive manufacturing via liquid dielectrophoresis.

Biomedical devices with millimeter and micron-scaled features have been a promising approach to single-cell analysis, diagnostics, and fundamental biological and chemical studies. These devices, however, have not been able to fully embrace the advantages of additive manufacturing (AM) that offers quick prototypes and complexities not achievable via traditional 2D fabrication techniques (e.g., soft lithography). This slow adoption of AM can be attributed in part to limited material selection, resolution, and inability to easily integrate components mid-print. Here, we present the feasibility of using liquid dielectrophoresis to manipulate and shape a droplet of build material, paired with subsequent curing and stacking, to generate 3D parts. This Electric Field Fabrication (EFF) technique is an additive manufacturing method that offers advantages such as new printable materials and mixed-media parts without post-assembly for biomedical applications.

A review: Dielectrophoresis for characterizing and separating similar cell subpopulations based on bioelectric property changes due to disease progression and therapy assessment.

This paper reviews the use of dielectrophoresis for high-fidelity separations and characterizations of subpopulations to highlight the recent advances in the electrokinetic field as well as provide insight into its progress toward commercialization. The role of cell subpopulations in heterogeneous clinical samples has been studied to deduce their role in disease progression and therapy resistance for instances such as cancer, tissue regeneration, and bacterial infection. Dielectrophoresis (DEP), a label-free electrokinetic technique, has been used to characterize and separate target subpopulations from mixed samples to determine disease severity, cell stemness, and drug efficacy. Despite its high sensitivity to characterize similar or related cells based on their differing bioelectric signatures, DEP has been slowly adopted both commercially and clinically. This review addresses the use of dielectrophoresis for the identification of target cell subtypes in stem cells, cancer cells, blood cells, and bacterial cells dependent on cell state and therapy exposure and addresses commercialization efforts in light of its sensitivity and future perspectives of the technology, both commercially and academically.

Highly Localized Enrichment of Trypanosoma brucei Parasites Using Dielectrophoresis.

Human African trypanosomiasis (HAT), also known as sleeping sickness, is a vector-borne neglected tropical disease endemic to rural sub-Saharan Africa. Current methods of early detection in the affected rural communities generally begin with general screening using the card agglutination test for trypanosomiasis (CATT), a serological test. However, the gold standard for confirmation of trypanosomiasis remains the direct observation of the causative parasite, Trypanosoma brucei. Here, we present the use of dielectrophoresis (DEP) to enrich T. brucei parasites in specific locations to facilitate their identification in a future diagnostic assay. DEP refers to physical movement that can be selectively induced on the parasites when exposing them to electric field gradients of specific magnitude, phase and frequency. The long-term goal of our work is to use DEP to selectively trap and enrich T. brucei in specific locations while eluting all other cells in a sample. This would allow for a diagnostic test that enables the user to characterize the presence of parasites in specific locations determined a priori instead of relying on scanning a sample. In the work presented here, we report the characterization of the conditions that lead to high enrichment, 780% in 50 s, of the parasite in specific locations using an array of titanium microelectrodes.

Management of the upper limb in cerebral palsy.

The management of the upper limb in cerebral palsy is often complex and challenging. Effective treatment requires a multidisciplinary approach involving paediatricians, occupational therapists, physiotherapists, orthotists and upper extremity surgeons. Interventions are generally aimed at improving function and cosmesis by spasticity management, preventing contractures and correcting established deformities. Treatment objectives vary according to each child and range from static correction of deformities to ease nursing care, to improvements in dynamic muscle balance to augment hand function. Botulinum toxin A therapy has been shown to relieve spasticity and improve function in the short term. Surgery is also effective but requires careful patient selection, as many children with cerebral palsy are not candidates for surgery. Occupational therapy and physiotherapy have small treatment effects alone but are essential adjuncts to medical and surgical management.

Functional and cosmetic outcome of surgery for cerebral palsy in the upper limb.

Function, cosmesis, hygiene, and ability to dress can be improved by appropriate surgery. This frequently involves multiple simultaneous procedures and addresses the muscles, their tendons, and the joints they pass over. The improvement in cosmesis is most profound in hemiplegic patients. Overall, patients are satisfied with the results of surgery.