An arteriovenous fistula (AVF) is the preferred vascular access for chronic hemodialysis, but high failure rates restrict its use. Optimizing patients’ perioperative status and the surgical technique, among other methods for preventing primary AVF failure, continue to fall short in lowering failure rates in clinical practice. One of the predominant causes of AVF failure is neointimal hyperplasia (NIH), a process that results from the synergistic effects of inflammation, hypoxia, and hemodynamic shear stress on vascular tissue. Although several systemic therapies have aimed at suppressing NIH, none has shown a clear benefit towards this goal. Localized therapeutic approaches may improve rates of AVF maturation by providing direct structural and functional support to the maturating fistula, as well as by delivering higher doses of pharmacologic agents while avoiding the adverse effects associated with systemic administration of therapeutic agents. Novel materials—such as polymeric scaffolds and nanoparticles—have enabled the development of different perivascular therapies, such as supportive mechanical devices, targeted drug delivery, and cell-based therapeutics. In this review, we summarize various perivascular therapeutic approaches, available data on their effectiveness, and the outlook for localized therapies targeting NIH in the setting of AVF for hemodialysis use. Highlights: Most systemic therapies do not improve AVF patency outcomes; therefore, localized therapeutic approaches may be beneficial. Locally delivered drugs and medical devices may improve AVF patency outcomes by providing biological and mechanical support. Cell-based therapies have shown promise in suppressing NIH by delivering a more extensive array of bioactive substances in response to the biochemical changes in the AVF microenvironment.

Our results demonstrate the preliminary safety and efficacy of a nearly completely absorbable filter in the inferior vena cava for short-term protection (<5 weeks) against pulmonary embolism. PurposeTo evaluate the immediate and long-term safety as well as thrombus-capturing efficacy for 5 weeks after implantation of an absorbable inferior vena cava (IVC) filter in a swine model.Materia...

Objective: To assess the diagnostic accuracy and safety of percutaneous biopsy for upper tract urothelial carcinoma ( UTUC ). Patients and Methods: From 2002 to 2013, 26 upper tract lesions in 24 patients (20 men; median [range] age 67.8 [51.7–85.9] years) were percutaneously biopsied. Analysis was separated based on lesion appearance: (i) mass infiltrating renal parenchyma, (ii) filling defect in the collecting system, (iii) urothelial wall thickening. We tracked immediate complications and tract seeding on follow‐up imaging. Results: Of the 26 upper tract lesions, 15 (58%) were masses infiltrating the renal parenchyma (mean [range] size 5.4 [1.1–14.0] cm), six (23%) were urothelial wall thickenings (mean [range] size 0.8 [0.4–1.1] cm), and five (19%) were filling defects within the renal pelvis or calyx (mean [range] size 2.7 [1.0–4.6] cm). Definitive diagnosis of UTUC was made by biopsy in 22 of 26 lesions (85%). Biopsy characterised 14 of 15 infiltrative masses and five of five filling defects; biopsy characterised three of six cases of urothelial wall thickening. CT follow‐up was available for 19 patients (73%) at a median (range) of 13.6 (1.0–98.9) months. Three patients (11%) developed recurrence in the nephrectomy bed at 5.6, 9.7, and 29.0 months after biopsy; none were attributed to tract seeding after independent review, because recurrence was remote from the biopsy site. Conclusion: Percutaneous biopsy is effective for diagnosis of UTUC , providing tissue diagnosis in 85% of cases. While case reports cite a risk of tract seeding, no cases of recurrence were definitely attributable to percutaneous biopsy. Thus, for upper tract urothelial lesions, which are not amenable to endoscopic biopsy, percutaneous biopsy is a safe and effective technique.

Cirrhosis, a marker of severe liver diseases, limits future liver remnant (FLR) growth, preventing many cancer patients from undergoing surgery. While portal vein blockade (PVB) techniques are used to stimulate liver regeneration, 20–30% of patients still fail to achieve the required growth. Although mesenchymal stem cell (MSC) therapy improves PVB, its efficacy is limited by poor cell retention. To address this, we utilized alginate hydrogels to deliver MSCs and improve their retention. MSCs were loaded in the hydrogel and injected intraportally in cirrhotic rats. Liver volume, weights, enzyme levels, and histology were monitored. Results showed that the hydrogel maintained 89.0 ± 3.0% cell viability and gradually released MSCs for over two weeks. Furthermore, the rats injected with the MSC-loaded hydrogel demonstrated higher liver volumes (FLR ratio of 0.57 ± 0.32) and weights (FLR ratio of 0.84 ± 0.05). The treated rats exhibited more improved liver enzymes (AST: 72.75 ± 14.17 U/L, ALP: 135.67 ± 41.20 U/L, ALT: 46.00 ± 2.94 U/L) and decreased fibrotic areas in the liver (4.52 ± 0.22%) compared to the control group. Histology revealed increased retention when MSCs were delivered with the hydrogel (37.30 ± 16.10 MSCs/mm²) compared to cells alone (21.70 ± 22.10 MSCs/mm²). Overall, the MSC-loaded hydrogels enhanced the growth and reduced the fibrosis of the liver by promoting cell retention and efficacy in cirrhotic rats. This approach holds significant potential for improving outcomes among cancer patients, offering a promising therapeutic strategy for liver regeneration and treatment of liver diseases.