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Öklü, Rahmi

https://orcid.org/0000-0003-4984-1778

Mayo Clinic

Mayo Clinic

Citations 86

Smart Catheters for Diagnosis, Monitoring, and Therapy
Tarman, Azra Yaprak , Ahmed, Samiha , Althumayri, Majed , Guy, Megan, Lugo, Darlenne Chavez, Ligler, Frances S. , Ligler, George T. , Öklü, Rahmi , Bova, Jonathan , Koydemir, Hatice Ceylan , Althumayri, Majed Othman , Kameoka, Jun , Bova, Jonathan , Ceylan Koydemir, Hatice , Oklu, Rahmi , Guy, Megan, Kawahira, Hiroshi , McShane, Michael J.

Advanced Healthcare Materials | November 17, 2025 | Volume: 15 | Issue: 13 | Pages: No page available

10.1002/adhm.202503913 Get It

Abstract This review explores smart catheters as an emerging class of medical devices that combine embedded sensors, robotics, and communication systems with increasing functionality and complexity to enable real‐time health monitoring, diagnostics, and treatment. Evolving from traditional catheters used as drains or entry ports, smart systems are now able to track blood pressure, temperature, biochemical signals, and mechanical forces within the body with a high degree of accuracy. Advances in materials, wireless communication, and robotic navigation have helped reduce common risks like infection and catheter blockage while also improving precision catheter placement for minimally invasive procedures. This review highlights recent developments across a variety of different types of smart catheters, ranging from sensing and imaging tools to therapeutic and multimodal systems. Additionally, it discusses the challenges that remain, including biocompatibility, long‐term performance, and clinical translation. The incorporation of new capabilities is changing how catheters are used, and these new uses promise to enable more personalized and responsive healthcare.
Ionic Liquid‐Reinforced Multifunctional Hydrogel for the Treatment of Enterocutaneous Fistula
Keum, Hyeongseop , Albadawi, Hassan , Altinbasak, Ismail , Yavuz, Furkan, Mishra, Nitin , Öklü, Rahmi , Kim, Jinjoo , Oklu, Rahmi , Graf, Erin H.

Advanced Materials | May 12, 2025 | Volume: 37 | Issue: 29 | Pages: No page available

10.1002/adma.202503179 Get It

AbstractEnterocutaneous fistulas (ECFs) profoundly impact patients’ quality of life, contributing to high morbidity rates and increased mortality due to ineffective treatment options. To address this challenge, ECFGel, a multifunctional, tissue adhesive injectable hydrogel, designed to occlude, sterilize, and promote healing of ECF tracts, is developed. ECFGel is formulated using gelatin and oxidized dextran (O‐Dex) as base components, which form chemical crosslinks within the hydrogel and with surrounding biological tissues, ensuring tissue adhesiveness. A choline and geranate‐based ionic liquid (IL) is incorporated to provide dual functionality, potent antimicrobial activity, and mechanical enhancement. By optimizing IL concentration, ECFGel achieves rapid gelation, enhanced mechanical strength, and improved elastic recoverability. Additionally, iohexol (IOH) is added for radiopacity, enabling real‐time imaging and further strengthening the hydrogel's mechanical properties. ECFGel demonstrates antiswelling properties, biodegradability, and effective tract occlusion in porcine soft tissues. It shows strong antimicrobial activity against highly resistant, patient‐derived pathogens isolated from clinical ECF cases. In a porcine perianal fistula model, ECFGel enables rapid occlusion and complete healing, promoting tissue maturation, reducing bacterial load, and increasing markers of cell proliferation and vascularization compared to untreated controls. These promising results highlight ECFGel's potential as a new therapeutic option for treating infected ECFs.
Catheter Injectable Multifunctional Biomaterial for the Treatment of Infected Enterocutaneous Fistulas
Albadawi, Hassan , Keum, Hyeongseop , Mayer, Joseph L. , Öklü, Rahmi , Kim, Jinjoo , Zhang, Zefu , Graf, Erin H. , Oklu, Rahmi

Advanced Science | February 14, 2025 | Volume: 12 | Issue: 20 | Pages: No page available

10.1002/advs.202414642 Get It

Abstract Enterocutaneous fistulas (ECF) are challenging to treat contributing to high morbidity and high mortality rates, significantly impacting the quality of life of the patients. Its susceptibility to antibiotic‐resistant infections often leads to chronic inflammation, complicating treatment with conventional methods. Here, 18NC75‐10P‐1IL is reported, which is a multi‐functional shear‐thinning hydrogel comprised of gelatin and nanosilicates for injectability, an ionic liquid for bactericidal effects, and platelet rich fibrin fraction for pro‐healing properties; this biomaterial is engineered for the treatment of ECFs. Through rigorous testing, the mechanical properties of 18NC75‐10P‐1IL were tailored for catheter injection to achieve durable occlusion of fistulous tracts under external pressures simulating clinical scenarios. 18NC75‐10P‐1IL demonstrated pro‐healing effects and anti‐microbial activity against highly resistant patient‐derived bacteria known to be associated with ECF. Subcutaneous implantation and anorectal fistula models confirmed its biocompatibility, pro‐healing, anti‐inflammatory, and anti‐microbial properties compared to control materials, suggesting promising potential for clinical translation in the treatment of human ECFs.
Liver Transplant Anatomy: Basics for Interventional Radiologists
Patel, Indravadan , Naidu, Sailendra , Wallace, Alex , Knuttinen, Grace , Alzubaidi, Sadeer , Özen, Merve , Crawford, Daniel A , Crawford, Daniel , Wallace, Alex, Öklü, Rahmi

Seminars in Interventional Radiology | February 4, 2025 | Volume: 42 | Issue: 02 | Pages: 234-238

10.1055/s-0045-1802649 Get It

AbstractLiver transplantation is becoming increasingly common in the United States, with very favorable 1- and 5-year survival rates. With increasing long-term survival rates, postprocedural vascular complications can occur with increased frequency. Familiarity with posttransplant vascular anatomy is essential for interventional radiologists dealing with this patient population. This article discusses the posttransplant venous, arterial, and biliary anatomy and the implications for minimally invasive interventions.
Multi‐Functional Biomaterial for the Treatment and Prevention of Central Line‐Associated Bloodstream Infections (Adv. Mater. 46/2024)
Albadawi, Hassan , Çevik, Enes , Kim, Jinjoo , Keum, Hyeongseop , Zhang, Zefu , Graf, Erin H. , Öklü, Rahmi

Advanced Materials | November 15, 2024 | Volume: 36 | Issue: 46 | Pages: No page available

10.1002/adma.202470365 Get It

Percutaneous Delivery of Oncogel for Targeted Liver Tumor Ablation and Controlled Release of Therapeutics (Adv. Mater. 45/2024)
Albadawi, Hassan , Çevik, Enes , Gündüz, Şeyda , Zhang, Zefu , Keum, Hyeongseop , Nagalo, Bolni Marius , Kita, Hirohito , Öklü, Rahmi

Advanced Materials | November 7, 2024 | Volume: 36 | Issue: 45 | Pages: No page available

10.1002/adma.202470363 Get It

Post–Liver Transplantation Vascular and Biliary Anatomy: A Pictorial Review
Al‐Ogaili, Mustafa , Baldawi, Jumana, Wallace, Alex, Alzubaidi, Sadeer , Knuttinen, Grace , Naidu, Sailendra , Patel, Indravadan , Öklü, Rahmi

Digestive Disease Interventions | September 20, 2024 | Volume: 09 | Issue: 02 | Pages: 094-099

10.1055/s-0044-1790523 Get It

AbstractThis article aims to assist radiologists in navigating the vascular and biliary anatomy of post-transplant patients, thereby enhancing their diagnostic accuracy and determining the need for potential interventions. We have detailed established methods for anastomosis between the donor and recipient arterial, hepatic venous, portal venous, and biliary systems, while omitting surgical techniques, vascular shunting, and operative procedures, as our primary audience is radiologists. The focus of this review is on inflow and outflow of both blood and bile. Given the numerous possible anastomosis points in hepatic transplantation, familiarizing radiologists with these variations will support their efforts in identifying crucial structures in post-transplant patients.
Multi‐Functional Biomaterial for the Treatment and Prevention of Central Line‐Associated Bloodstream Infections
Keum, Hyeongseop , Albadawi, Hassan , Zhang, Zefu , Çevik, Enes , Öklü, Rahmi , Kim, Jinjoo , Graf, Erin H. , Oklu, Rahmi

Advanced Materials | August 15, 2024 | Volume: 36 | Issue: 46 | Pages: No page available

10.1002/adma.202405805 Get It

AbstractCentral venous catheters are among the most used medical devices in hospitals today. Despite advances in modern medicine, catheter infections remain prevalent, causing significant morbidity and mortality worldwide. Here, SteriGel is reported, which is a multifunctional hydrogel engineered to prevent and treat central line‐associated bloodstream infections (CLABSI). The mechanical properties of SteriGel are optimized to ensure appropriate gelation kinetics, bio‐adhesiveness, stretchability, and recoverability to promote durability upon application and to provide persistent protection against infection. In vitro assays demonstrated that SteriGel exhibits long‐term antimicrobial efficacy and has bactericidal effects against highly resistant patient‐derived pathogens known to be frequently associated with CLABSI. SteriGel outperformed Biopatch, which is a clinically used device for CLABSI, in ex vivo cadaver studies that simulate clinical scenarios. Furthermore, SteriGel has biocompatible, pro‐healing, and anti‐inflammatory properties in vitro and in a rat subcutaneous injection model, suggesting a potential synergistic effect in the prevention and treatment of CLABSI. SteriGel is a multifunctional adherent biomaterial with potent antimicrobial effects for sustained sterility while promoting healing of the catheter incision site to protect against infection.
Percutaneous Delivery of Oncogel for Targeted Liver Tumor Ablation and Controlled Release of Therapeutics
Albadawi, Hassan , Zhang, Zefu , Keum, Hyeongseop , Çevik, Enes , Nagalo, Bolni Marius , Gündüz, Şeyda , Kita, Hirohito , Öklü, Rahmi , Oklu, Rahmi , Kita, H , Nagalo, Bolni

Advanced Materials | August 15, 2024 | Volume: 36 | Issue: 45 | Pages: No page available

10.1002/adma.202406080 Get It

Abstract Advanced‐stage liver cancers are associated with poor prognosis and have limited treatment options, often leading the patient to hospice care. Percutaneous intratumoral injection of anticancer agents has emerged as a potential alternative to systemic therapy to overcome tumor barriers, increase bioavailability, potentiate immunotherapy, and avoid systemic toxicity, which advanced‐stage cancer patients cannot tolerate. Here, an injectable OncoGel (OG) comprising of a nanocomposite hydrogel loaded with an ionic liquid (IL) is developed for achieving a predictable and uniform tumor ablation and long‐term slow release of anticancer agents into the ablation zone. Rigorous mechanical, physiochemical, drug release, cytotoxicity experiments, and ex vivo human tissue testing identify an injectable version of the OG with bactericidal properties against highly resistant bacteria. Intratumoral injection of OG loaded with Nivolumab (Nivo) and doxorubicin (Dox) into highly malignant tumor models in mice, rats, and rabbits demonstrates enhanced survival and tumor regression associated with robust tissue ablation and drug distribution throughout the tumor. Mass cytometry and proteomic studies in a mouse model of colorectal cancer that often metastasizes to the liver indicate an enhanced anticancer immune response following the intratumoral injection of OG. OG may augment immunotherapy and potentially improve outcomes in liver cancer patients.
Tissue Ablation: Applications and Perspectives (Adv. Mater. 32/2024)
Çevik, Enes , Demirlenk, Yusuf Mert , Atar, Dila , Saini, Gia , Sheth, Rahul A. , Keum, Hyeongseop , Kim, Jinjoo , Deipolyi, Amy R. , Öklü, Rahmi

Advanced Materials | August 8, 2024 | Volume: 36 | Issue: 32 | Pages: No page available

10.1002/adma.202470259 Get It