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Cormode, D. P.

Publications and source records attributed to Cormode, D. P..

9 recordsLinked to original sources

Open-source robotic chip-to-plate interface for high-throughput microfluidic generation of materials libraries

Data-driven materials development requires large, well-characterized libraries of precisely defined formulations. While microfluidic platforms excel at generating highly controlled materials, their throughput is often limited by the challenge of efficiently interfacing device outputs with standard well plates. This bottleneck frequently necessitates manual transfer or non-microfluidic workflows, constraining both throughput and reproducibility. Here, we present LMNOP-bot (Libraries of Micro- and Nano-materials, OPen-source bot), an open-source robotic platform for the automated generation and collection of micro- and nanomaterial libraries from serial microfluidic outputs. Using synchronized, pressure-driven flow, LMNOP-bot enables continuous formulation and direct deposition into standard well plates. The system is low-cost (<$700, excluding pressure regulators), constructed from readily available or easily fabricated components, and designed for broad accessibility. LMNOP-bot collects [&ge;]30 {micro}L per formulation at a rate of one sample every four seconds, representing an approximately 50x increase in throughput over existing serial microfluidic workflows, and operates robustly for over 10,000 runs without maintenance. We demonstrate compatibility with both PDMS/glass and commercial polycarbonate devices, with seamless interfacing to 96- and 384-well plates. Repeated sampling confirms high precision and reproducibility. By removing a key bottleneck in microfluidic library generation, LMNOP-bot enables rapid, scalable, and accessible exploration of material design spaces.

bioengineering↗

Drug-Eluting, Radiopaque, Tumor-Casting Hydrogels for Endovascular Locoregional Therapy of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide. For patients with unresectable disease, locoregional therapies, such as transarterial chemoembolization (TACE), are the standard of care. However, even with this treatment, the average survival rate is only 27% at 5 years. Recent studies have demonstrated the potential of novel approaches to improve responses through more complete embolization and targeting ischemia-induced molecular dependencies. To build on these findings, we developed an injectable chitosan-based hydrogel system (AuNP-Lys05-gel) that we hypothesized might be a more effective embolic material by (i) enabling a more complete filling of tumor feeding blood vessels in a cast-like manner, (ii) encapsulating Lys05, a potent autophagy inhibitor, and (iii) providing X-ray contrast for direct visualization of the embolization. Chitosan hydrogels of varying composition were formed and characterized. We found that Lys05 could be loaded in this type of hydrogel and that it was released gradually over 7 days. We found that AuNP was better retained by the hydrogel than iopamidol, an FDA-approved contrast agent, indicating that AuNP would provide longer-lasting CT monitoring. In a rat model of HCC, AuNP-Lys05-gel reduced tumor growth and resulted in a 67% objective response rate vs 26% for a clinically used particle embolic. Histology indicated effective vascular occlusion by the gel. These findings indicate that AuNP-Lys05-gel merits further investigation as a treatment for HCC.

cancer biology↗

Transarterial Embolization Using a Liquid Embolic Enhances Tumor Necrosis to Enable Improved Efficacy Compared with a Particle Embolic in a Translational Rat Model of Hepatocellular Carcinoma

PurposeTo compare the effectiveness of transarterial embolization (TAE) using a liquid embolic (LE) to TAE using particle embolics (PE) with respect to tumor ischemia and treatment response in a translational rat model. Materials and MethodsHCC was induced in male Wistar rats using diethylnitrosamine. Rats were randomized into three treatment groups: sham transarterial embolization (TAE), TAE with LE, and TAE with PE. Tumor response to TAE was monitored via serial T2-weighted MRI scans and assessed using RECIST. Tumor necrosis and hypoxia were assessed through hematoxylin and eosin staining and pimonidazole immunohistochemistry, respectively. Statistical analyses were performed using chi-square tests, Kaplan-Meier estimates, and one-way ANOVAs, with significance set at p<0.05. ResultsTwenty-nine rats were randomized to TAE with LE (n=13), PE (n=13), or sham (n=3). TAE with LE demonstrated a significantly higher objective response rate (83%) compared to TAE with PE (28%; {chi}2 = 11.25, P=0.0008). Complete responses were observed in 50% of the LE-treated tumors versus 10% in the PE-treated group. LE treatment prolonged local progression-free survival (hazard ratio = 0.23; p=0.0085). Histological analysis, with an additional 14 rats randomized to TAE with LE (n=5), PE (n=6), or sham (n=3), showed greater necrosis and hypoxia in LE-treated tumors compared to PE. LE induced a significant reduction in viable tumor tissue (p<0.05) and increased necrotic and hypoxic tissue areas compared to PE (p<0.01). ConclusionLE significantly enhanced the therapeutic efficacy of TAE in a rat model of HCC compared to conventional PE. The results highlight LEs potential to improve ischemia and necrosis, thereby offering a promising option improving the efficacy of embolization for HCC treatment.

cancer biology↗

The effect of the size of gold nanoparticle contrast agents on CT imaging of the gastrointestinal tract and inflammatory bowel disease

Ulcerative colitis (UC) is a chronic inflammatory bowel disease (IBD). CT imaging with contrast agents is commonly used for visualizing the gastrointestinal (GI) tract in UC patients. CT is a common imaging modality for evaluating IBD, especially in patients with acute abdominal pain presenting to emergency departments. CTs major limitation lies in its lack of specificity for imaging UC, as the commonly used agents are not well-suited for inflamed areas. Recent studies gastrointestinal tract (GIT) in UC. Further systemic research is needed to explore novel contrast agents that can specifically image disease processes in this disease setting.

bioengineering↗

Towards the Clinical Translation of a Silver Sulfide Nanoparticle Contrast Agent: Large Scale Production with a Highly Parallelized Microfluidic Chip

Ultrasmall silver sulfide nanoparticles (Ag2S-NP) have been identified as promising contrast agents for a number of modalities and in particular for dual-energy mammography. These Ag2S-NP have demonstrated marked advantages over clinically available agents with the ability to generate higher contrast with high biocompatibility. However, current synthesis methods are low-throughput and highly time-intensive, limiting the possibility of large animal studies or eventual clinical use of this potential imaging agent. We herein report the use of a scalable silicon microfluidic system (SSMS) for the large-scale synthesis of Ag2S-NP. Using SSMS chips with 1 channel, 10 parallelized channels, and 256 parallelized channels, we determined that the Ag2S-NP produced were of similar quality as measured by core size, concentration, UV-visible spectrometry, and in vitro contrast generation. Moreover, by combining parallelized chips with increasing reagent concentration, we were able to increase output by an overall factor of 3,400. We also found that in vivo imaging contrast generation was consistent across synthesis methods and confirmed renal clearance of the ultrasmall nanoparticles. Finally, we found best-in-class clearance of the Ag2S-NP occurred within 24 hours. These studies have identified a promising method for the large-scale production of Ag2S-NP, paving the way for eventual clinical translation.

bioengineering↗

A biodegradable "one-for-all" nanoparticle for multimodality imaging and enhanced photothermal treatment of breast cancer

Silver sulfide nanoparticles (Ag2S-NP) have been proposed for various optical-based biomedical applications, such as near-infrared fluorescence (NIRF) imaging, photoacoustics (PA) and photothermal therapy (PTT). However, their absorbance is relatively low in the NIR window used in these applications, and previous formulations were synthesized using toxic precursors under harsh conditions and have clearance issues due to their large size. Herein, we synthesized sub-5 nm Ag2S-NP and encapsulated them in biodegradable, polymeric nanoparticles (AgPCPP). All syntheses were conducted using biocompatible reagents in the aqueous phase and under ambient conditions. We found that the encapsulation of Ag2S-NP in polymeric nanospheres greatly increases their NIR absorbance, resulting in enhanced optical imaging and photothermal heating effects. We therefore found that AgPCPP have potent contrast properties for PA and NIRF imaging, as well as for computed tomography (CT). We demonstrated the applicability of AgPCPP nanoparticles as a multimodal imaging probe that readily improves the conspicuity of breast tumors in vivo. PTT was performed using AgPCPP with NIR laser irradiation, which led to significant reduction in breast tumor growth and prolonged survival compared to free Ag2S-NP. Lastly, we observed a gradual decrease in AgPCPP retention in tissues over time with no signs of acute toxicity, thus providing strong evidence of safety and biodegradability. Therefore, AgPCPP may serve as a "one-for-all" theranostic agent that degrades into small components for excretion once the diagnostic and therapeutic tasks are fulfilled, thus providing good prospects for translation to clinical use. TOC graphic O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=119 SRC="FIGDIR/small/568885v1_ufig1.gif" ALT="Figure 1"> View larger version (28K): org.highwire.dtl.DTLVardef@e6be5dorg.highwire.dtl.DTLVardef@dbce2eorg.highwire.dtl.DTLVardef@bd5360org.highwire.dtl.DTLVardef@1acf01d_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioengineering↗

Theranostic gold in a gold cage nanoparticle for photothermal ablation and photoacoustic imaging of skin and oral infections

AbstractBiofilms are structured communities of microbial cells embedded in a self-produced matrix of extracellular polymeric substances. Biofilms are associated with many health issues in humans, including chronic wound infections and tooth decay. Current antimicrobials are often incapable of disrupting the polymeric biofilm matrix and reaching the bacteria within. Alternative approaches are needed. Here, we describe a unique structure of dextran coated gold in a gold cage nanoparticle that enables photoacoustic and photothermal properties for biofilm detection and treatment. Activation of these nanoparticles with a near infrared laser can selectively detect and kill biofilm bacteria with precise spatial control and in a short timeframe. We observe a strong biocidal effect against both Streptococcus mutans and Staphylococcus aureus biofilms in mouse models of oral plaque and wound infections respectively. These effects were over 100 times greater than that seen with chlorhexidine, a conventional antimicrobial agent. Moreover, this approach did not adversely affect surrounding tissues. We conclude that photothermal ablation using theranostic nanoparticles is a rapid, precise, and non-toxic method to detect and treat biofilm-associated infections.

bioengineering↗

A novel injectable radiopaque hydrogel with potent properties for multicolor CT imaging in the context of brain and cartilage regenerative therapy

Cell therapy is promising to treat many conditions, including neurological and osteoarticular diseases. Encapsulation of cells within hydrogels facilitates cell delivery and can improve therapeutic effects. However, much work remains to be done to align treatment strategies with specific diseases. The development of imaging tools that enable monitoring cells and hydrogel independently is key to achieving this goal. Our objective herein is to longitudinally study an iodine-labeled hydrogel, incorporating gold-labeled stem cells, by bicolor CT imaging after in vivo injection in rodent brains or knees. To this aim, an injectable self-healing hyaluronic acid (HA) hydrogel with long-persistent radiopacity was formed by the covalent grafting of a clinical contrast agent on HA. The labeling conditions were tuned to achieve sufficient X-ray signal and to maintain the mechanical and self-healing properties as well as injectability of the original HA scaffold. The efficient delivery of both cells and hydrogel at the targeted sites was demonstrated by synchrotron K-edge subtraction-CT. The iodine labeling enabled to monitor the hydrogel biodistribution in vivo up to 3 days post-administration, which represents a technological first in the field of molecular CT imaging agents. This tool may foster the translation of combined cell-hydrogel therapies into the clinics.

bioengineering↗

Myeloid cell mPGES-1 mediates inflammatory pain hypersensitivity in mice.

Nonsteroidal anti-inflammatory drugs (NSAIDs) relieve inflammatory pain by predominant suppression of cyclooxygenase-2 derived prostaglandin (PG) E2. Innate immune cells contribute to inflammatory pain hypersensitivity and may be an attractive target for novel non-addictive approaches to pain management. We studied the contribution of PGE2 produced by myeloid cell microsomal prostaglandin E synthase -1 (mPGES-1) to peripheral inflammation and hyperalgesia in mice. Selective deletion of mPGES-1 in myeloid cells by crossing LysM-Cre mice with mPGES-1flox/flox mice (Mac-mPGES-1-KO) resulted in significantly reduced mechanical and thermal hyperalgesia in complete Freunds adjuvant (CFA)-evoked hind paw inflammation, zymosan-induced peri-articular inflammation and collagen II antibody-induced arthritis models. Systemic COX-2 inhibition or myeloid cell specific COX-2 deletion (by crossing LysM-Cre with COX-2 flox/flox mice) recapitulated reduction of CFA-induced inflammation and hyperalgesia. In contrast, deletion of mPGES-1 in neurons and glial cells by crossing mPGES-1flox/flox mice with Nestin-Cre mice had no detectable effect on inflammatory pain hypersensitivity. While macrophage recruitment was unaltered, tissue concentrations of PGE2, IL-1{beta} and TNF were significantly reduced in Mac-mPGES-1-KO paw tissues following CFA induction. Our results demonstrate that myeloid cell mPGES-1 is the dominant source of PGE2 in inflammatory pain hypersensitivity. Targeting myeloid cell mPGES-1 may afford a novel approach to inflammatory pain therapy.

pharmacology and toxicology↗