Using Deep Image Prior to Assist Variational Selective Segmentation Deep Learning Algorithms

Variational segmentation algorithms require a prior imposed in the form of a regularisation term to enforce smoothness of the solution. Recently, it was shown in the Deep Image Prior work that the explicit regularisation in a model can be removed and replaced by the implicit regularisation captured by the architecture of a neural network. The Deep Image Prior approach is competitive, but is only tailored to one specific image and does not allow us to predict future images. We propose to incorporate the ideas from Deep Image Prior into a more traditional learning algorithm to allow us to use the implicit regularisation offered by the Deep Image Prior, but still be able to predict future images.Comment: Presented at SIPAIM 202

Stent frame movement following endovascular aneurysm sealing in the abdominal aorta

Purpose: We investigated the incidence and extent of stent migration after endovascular sealing of abdominal aortic aneurysms (EVAS), its relationship with adherence to the instructions for use of the Nellix endograft and its association with aneurysm growth. Methods: In this retrospective single centre study, the clinical data and follow-up CT images of patients undergoing infra-renal EVAS with a minimum follow-up of 1 year were reviewed. The first postoperative CT scan at one month and the subsequent scans were used to measure the distances between the proximal end of the stent and reference visceral vessels using a previously validated technique. Device migration was based on the Society of Vascular Surgery definition of >10mm downward movement of either Nellix stent in the proximal landing zone; furthermore, we defined proximal displacement a downward movement of ≥4mm. Patients were categorised according to adherence to the old (2013) or new (2016) Nellix IFU. Aneurysm diameter was measured for each scan and a change of ≥5mm was deemed indicative of aneurysm growth. Results: Seventy-five patients were eligible for inclusion in our study. Over a 4-year period, migration ≥4mm occurred in 42 (56%) patients and migration of ≥10mm in 16 (21%), with similar incidence in right and left stents. Migration ≥4mm was significantly more frequent among patients whose anatomy did not conform to any IFU (p=0.025). Presence of aneurysm growth ≥5mm was observed in 14 patients (19%) and was significantly associated with proximal displacement ≥4mm (p=0.03). Conclusion: Infra-renal EVAS may be complicated by proximal displacement and migration, particularly when performed outside IFU. The definition of migration used for EVAR is inappropriate for EVAS; a new consensus on definition and measurement technique is necessary

Potential therapeutic effects of natural heme oxygenase-1 inducers in cardiovascular diseases.

Significance: Many physiological effects of natural antioxidants, their extracts or their major active components, have been reported in recent decades. Most of these compounds are characterized by a phenolic structure, similar to that of α-tocopherol, and present antioxidant properties that have been demonstrated both in vitro and in vivo. Polyphenols may increase the capacity of endogenous antioxidant defenses and modulate the cellular redox state. Such effects may have wide-ranging consequences for cellular growth and differentiation. Critical Issues: The majority of in vitro and in vivo studies conducted so far have attributed the protective effect of bioactive polyphenols to their chemical reactivity toward free radicals and their capacity to prevent the oxidation of important intracellular components. One possible protective molecular mechanism of polyphenols is nuclear factor erythroid 2-related factor (Nrf2) activation, which in turn regulates a number of detoxification enzymes. Recent Advances: Among the latter, the heme oxygenase-1 (HO-1) pathway is likely to contribute to the established and powerful antioxidant/anti-inflammatory properties of polyphenols. In this context, it is interesting to note that induction of HO-1 expression by means of natural compounds contributes to prevention of cardiovascular diseases in various experimental models. Future Directions: The focus of this review is on the role of natural HO-1 inducers as a potential therapeutic strategy to protect the cardiovascular system against various stressors in several pathological conditions

Glucocorticoid-Induced Leucine Zipper (GILZ) in Cardiovascular Health and Disease

Glucocorticoids (GCs) are essential in regulating functions and homeostasis in many biological systems and are extensively used to treat a variety of conditions associated with immune/inflammatory processes. GCs are among the most powerful drugs for the treatment of autoimmune and inflammatory diseases, but their long-term usage is limited by severe adverse effects. For this reason, to envision new therapies devoid of typical GC side effects, research has focused on expanding the knowledge of cellular and molecular effects of GCs. GC-induced leucine zipper (GILZ) is a GC-target protein shown to mediate several actions of GCs, including inhibition of the NF-κB and MAPK pathways. GILZ expression is not restricted to immune cells, and it has been shown to play a regulatory role in many organs and tissues, including the cardiovascular system. Research on the role of GILZ on endothelial cells has demonstrated its ability to modulate the inflammatory cascade, resulting in a downregulation of cytokines, chemokines, and cellular adhesion molecules. GILZ also has the capacity to protect myocardial cells, as its deletion makes the heart, after a deleterious stimulus, more susceptible to apoptosis, immune cell infiltration, hypertrophy, and impaired function. Despite these advances, we have only just begun to appreciate the relevance of GILZ in cardiovascular homeostasis and dysfunction. This review summarizes the current understanding of the role of GILZ in modulating biological processes relevant to cardiovascular biology

Takotsubo syndrome in a young woman during puerperium: case report

Introduction. Takotsubo syndrome is a reversibile cardiomyopathy that often occurs during an emotional stress and is more frequent in post-menopausal women. Case presentation. We describe a clinic case of a 42 years old woman, admitted to our emergency unit because of a thoracic pain. The ECG showed ST-T elevation in V1- V4, the echocardiography revealed akinesia of apical segment of left ventricle. Coronary arteries were free from significant stenosis and ventriculography showed akinesia of apical segment of left ventricle. In the following days, ECG evolved toward a normalization of ST-T segment with appearance of negative T wave in V2-V6, and also the echocardiography showed a normalized LV wall motion. The patient was discharged and ECG and echocardiography were normal at two months follow up. Conclusion. In this case report, a young woman during puerperium presented with a Takotsubo syndrome. We speculate that the high Prolactin level and her emotional state contributed to the clinical manifestation of the syndrome

Topical rifampicin for prevention of deep sternal wound infections in patients undergoing coronary artery bypass grafting

Deep sternal wound infections (DSWI), although an infrequent complication, significantly impair postoperative outcomes after coronary artery bypass grafting (CABG) surgery. Among several preventive strategies, topical antibiotic therapy immediately before sternal closure has been strongly advocated. In this retrospective analysis, the incidence of DSWI in 517 patients undergoing isolated CABG and receiving rifampicin irrigation of mediastinum, sternum and suprasternal tissues was compared to an historical consecutive cohort of 448 patients. To account for the inherent selection bias, a 1:1 propensity matched analysis was performed. Patients receiving topical rifampicin experienced significantly less occurrence of postoperative DSWI (0.2% vs 2.5%, p = 0.0016 in the unmatched analysis; 0.3% vs 2.1%, p = 0.0391 in the matched analysis). Intensive care unit stay, hospital stay, and operative mortality were similar between groups. This study shows that topical rifampicin in combination with commonly prescribed preventative strategies significantly reduces the incidence of DSWI to less than 0.3% in unselected patients undergoing a full median sternotomy for CABG. Further studies, including a larger number of patients and with a randomization design, would establish the potential preventative role of topical rifampicin in reducing the occurrence of DSWI

Migration of the Nellix Endoprosthesis

Background This study reports the incidence and sequelae of migration of the Nellix (Endologix Inc, Irvine, Calif) endoprosthesis after endovascular aneurysm sealing. Methods A review was performed of the follow-up imaging of all endovascular aneurysm sealing patients in a university hospital endovascular program who had a minimum follow-up of 1 year. The first postoperative and latest follow-up computed tomography scans were used to measure the distances between the proximal and distal borders of the stent grafts relative to reference vessels using a previously validated technique. Device migration was based on previously established criteria and defined as any stent graft movement of ≥4 mm related to a predefined reference vessel. Device movement in a caudal direction was given a positive value, and movement in a cranial direction was denoted by a negative value. Results Eighteen patients (35 stent grafts) were eligible for inclusion in this retrospective review. The mean preoperative abdominal aortic aneurysm diameter was 57 mm (standard deviation [SD], 5; range, 50-67 mm) and aortic neck length was 30 mm (SD, 16; range, 6-62 mm). Proximal migration, according to study definitions, was identified in six stent grafts (17%), all in a caudal direction. At 1 year the mean proximal migration distance was +6.6 mm (SD, 1.6; range, +4.7-+9.2 mm). Migration occurred in a single stent graft in four patients and bilaterally in one. No distal migration occurred. Conclusions Proximal migration of the Nellix endoprosthesis does occur and was without any sequelae in our series. Further investigations into the long-term positional stability of the Nellix device, together with a more thorough understanding of the etiology and consequences of migration, are required. Author conflict of interest: F.T. and R.F.K. have received professional fees and educational grants from Endologix. The editors and reviewers of this article have no relevant financial relationships to disclose per the JVS policy that requires reviewers to decline review of any manuscript for which they may have a conflict of interest