Role of hypoxia inducible factor HIF-1α in heart valves.

The 2016 Albert Lasker Basic Medical Research Award and subsequently the 2019 Nobel Prize in Physiology or Medicine were awarded to William Kaelin, Jr., Sir Peter Ratcliffe, and Gregg Semenza for their work on how cells sense and adapt to hypoxic conditions. Their work showed that the changes in gene expression, cell metabolism, and tissue remodelling that occur in response to low oxygen concentrations are orchestrated by the transcription factor, hypoxia inducible factor-1α (HIF-1α). While the effects mediated by HIF-1α have been widely studied, its role in heart valves has only recently been investigated. These studies have shown that HIF-1α expression is evident in mechanisms that regulate the structure and function of heart valves. These include embryonic development, the regulation of the extracellular matrix, angiogenesis and the initiation of the calcification process. This review provides a background on the role and function of HIF-1α in response to hypoxia and a discussion of the available evidence of its involvement in the regulation of heart valves in health and disease.

Vertebral augmentation with spinal implants: third-generation vertebroplasty.

This article is to review the different types of vertebral augmentation implants recently becoming available for the treatment of benign and malignant spinal compression fractures. After a detailed description of the augmentation implants, we review the available clinical data. We will conclude with a summary of the advantages and disadvantages of vertebral implants and how they can affect the future treatment options of compression fractures.

Multicenter clinical and imaging evaluation of targeted radiofrequency ablation (t-RFA) and cement augmentation of neoplastic vertebral lesions.

BACKGROUND: Treatment of spinal metastatic lesions by radiofrequency ablation (RFA) before cementation can potentially help in local tumor control and pain relief. This is often limited by access and tumor location. This study reports multicenter clinical and imaging outcomes following targeted RFA (t-RFA) and cement augmentation in neoplastic lesions of the spine. MATERIAL AND METHODS: A retrospective multicenter study of 49 patients with 72 painful vertebral lesions, evaluated for clinical and imaging outcomes following RFA and cement augmentation of spinal metastatic lesions, was undertaken. Visual Analogue Pain score (VAS) and Oswestry Disability Index (ODI) were obtained before and 2-4 weeks after treatment. Pre- and post-procedure imaging examinations including MRI and positron emission tomography (PET) were also evaluated. RESULTS: Mean ablation time was 3.7±2.5 min (range 0.92-15). Mean VAS scores decreased from 7.9±2.5 pre-procedure to 3.5±2.6 post-procedure (p<0.0001). Mean ODI scores improved from 34.9±18.3 to 21.6±13.8 post-procedure (p<0.0001). Post-contrast MRI resulted in a predictable pattern of decreased tumor volume and an enhancing rim. Metabolically active lesions in pre-procedure PET scans (n=10 levels) showed decreased fluorodeoxyglucose activity after ablation. CONCLUSIONS: t-RFA followed by vertebral augmentation in malignant vertebral lesions resulted in significant pain reduction and functional status improvement, with no major complications. t-RFA permitted access to vertebral lesions and real-time accurate monitoring of the ablation zone temperature. Post-procedure MRI and PET examinations correlated with a favorable tumor response and helped to monitor tumor growth and the timing of adjuvant therapy.

What Is the Role of the Bacterium Propionibacterium acnes in Type 1 Modic Changes? A Review of the Literature.

This review presents a summary of the pathology and epidemiology of Modic changes and the possible role of Propionibacterium acnes. This information is followed by a synthesis of the most recent clinical research involved in culturing the discs of patients with degenerative disc disease for the presence of bacteria. We also discuss a randomized controlled trial that investigates the effects of antibiotics on patients with chronic low back pain and type 1 Modic changes. We conclude with a brief discussion of the difficulties involved in this research and the significance of the findings.

Spinal cord stimulators in an outpatient interventional neuroradiology practice.

PURPOSE: Spinal cord stimulation is a known modality for the treatment of chronic back and neck pain. Traditionally, spine surgeons and pain physicians perform the procedures. We report our experience in performing neuromodulation procedures in an outpatient interventional neuroradiology practice. METHODS: A retrospective analysis of medical records of all trial and permanent implantation patients over a period of 4 years was performed. 45 patients (32 men) of median age 47 years were included in the study. The primary diagnoses were 23 cases of failed back or neck surgery syndrome, 12 cases of spinal stenosis, 4 cases of axial pain, 3 cases with reflex sympathetic dystrophy, 1 case of peripheral vascular disease, 1 case of phantom limb and 1 case of post-concussion syndrome. RESULTS: Thirty-four trials were performed in an outpatient clinic while 11 trials were performed in hospital outpatient settings. Trial periods were 3-7 days. 27 patients (60%) who reported ≥50% pain relief underwent a permanent implantation. An interventional neuroradiologist performed 17 implantations, while spine surgeons performed 10 implantations. 23 implants were epidural (19 lumbar and 4 cervical) and four implants were subcutaneous. During the follow-up period, three patients had infections (13%) and required removal of the device and two cases (8%) reported lead migration. CONCLUSIONS: Neuromodulation procedures can be performed safely in an outpatient interventional radiology setting. Although the infection rate was relatively higher in this study population, the other complication rates and trial-to-implant ratio are similar to published data.