ERASMO SIMAO DA SILVA
Projetos de Pesquisa
Unidades Organizacionais
Departamento de Cirurgia, Faculdade de Medicina - Docente
LIM/02 - Laboratório de Anatomia Médico-Cirúrgica, Hospital das Clínicas, Faculdade de Medicina - Líder
LIM/02 - Laboratório de Anatomia Médico-Cirúrgica, Hospital das Clínicas, Faculdade de Medicina - Líder
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- The Distensibility of the Human Vena Cava and Its Importance to In Vitro Studies of Venous Compression Syndromes: A Search for a Suitable Polymer for 3-Dimensional Printing(2023) PUECH-LEAO, Pedro; TORRES, Inez O.; SILVA, Erasmo S. da; CESTARI, Ismar N.; CESTARI, Idagene A.; ROSA, Jhenyfer M. da; NAHAS, William C.; LUCCIA, Nelson DeBackground: Venous compression syndromes are clinical conditions in which the large veins are compressed by other anatomical structures. Laboratory simulations may help us better understand the hemodynamics in venous compressions by creating situations similar to those seen in vivo. The aim of this study is to produce a model of the caval bifurcation using a polymer with distensibility similar to the human vena cava. Methods: Fragments of the inferior vena cava were collected from 13 deceased kidney donors (aged 15-37 years) and were tested for deformation (strain) when subjected to distension at 50 N/cm2. Strips of 5 different polymers-thermic polyurethane and Agilus30 with Vero Magenta (AV) (in 3 different hardnesses) and silicone-were subjected to the same biomechanical tests and compared with the vena cava. A model of the caval bifurcation was produced with 3-D printing. Results: The deformation (strain) of the vena cava wall was 0.16 & PLUSMN; 0.9 when submitted to stress close to 50 N/cm2. Silicone showed a strain higher than the standard deviation of venous fragments. The strain of AV resin 95 Shore was lower than the standard deviation of the venous fragments. AV Resins 70 and 85 Shore showed strains within the standard deviation of the venous specimen, with 70 Shore being closest to the mean venous strain. Therefore, this material was selected for modeling the caval bifurcation. The computed tomography scan image generated a computer model of the caval bifurcation and was printed in 3 dimensions. In addition, the segments of 2 adjacent vertebrae were also printed to reference the compression site. Conclusions: The 3-D printing of large veins can produce models with anatomy and biome-chanics similar to those of human veins and opens a field of investigation into the hemody-namics of venous compression syndromes. Polymers with Shore A70 appear to have biomechanical properties similar to those of the vena cava wall. The model obtained in this study can be used in several in vitro studies of May-Thurner Syndrome.
- Cysteine and glycine-rich protein 3 (Crp3) as a critical regulator of elastolysis, inflammation, and smooth muscle cell apoptosis in abdominal aortic aneurysm development(2023) MATTOS, Ana Barbosa Marcondes de; RIBEIRO-SILVA, Joao Carlos; FONSECA-ALANIZ, Miriam Helena; VALADAO, Iuri Cordeiro; SILVA, Erasmo Simao da; KRIEGER, Jose Eduardo; MIYAKAWA, Ayumi AureaAbdominal aortic aneurysm (AAA) is a life-threatening vascular disease for which surgical or endovascular repair are the only currently available therapeutic strategies. The development of AAA involves the breakdown of elastic fibers (elastolysis), infiltration of inflammatory cells, and apoptosis of smooth muscle cells (SMCs). However, the specific regulators governing these responses remain unknown. We previously demonstrated that Cysteine and glycine-rich protein 3 (Crp3) sensitizes SMCs to apoptosis induced by stretching. Building upon this finding, we aimed to investigate the influence of Crp3 on elastolysis and apoptosis during AAA development. Using the elastase-CaCl2 rat model, we observed an increase in Crp3 expression, aortic diameter, and a reduction in wall thickness in wild type rats. In contrast, Crp3-/- rats exhibited a decreased incidence of AAA, with minimal or no changes in aortic diameter and thickness. Histopathological analysis revealed the absence of SMC apoptosis and degradation of elastic fibers in Crp3-/- rats, accompanied by reduced inflammation and diminished proteolytic capacity in Crp3-/- SMCs and bone marrow-derived macrophages. Collectively, our findings provide evidence that Crp3 plays a crucial role in AAA development by modulating elastolysis, inflammation, and SMC apoptosis. These results underscore the potential significance of Crp3 in the context of AAA progression and offer new insights into therapeutic targets for this disease.
- In Hospital and Long Term Outcomes After Repair of Subclavian and Axillary Artery Injuries(2023) TORRES, Inez Ohashi; ANDRADE, Rebeca Cristina Lourenco de; APOLONI, Rafael; SILVA, Erasmo Simao da; PUECH-LEAO, Pedro; LUCCIA, Nelson DeObjective: To evaluate the in hospital and long term outcomes after open or endovascular repair of subclavian and axillary artery injuries.Methods: This was a retrospective, single centre study. Data were reviewed from patients with subclavian and or axillary injuries who presented to the authors' centre between January 2009 and December 2022. Outcome data included complications, death, amputations, and re-interventions. A p value < .050 was considered to be statistically significant.Results: Over the study period, 62 patients with subclavian or axillary trauma were admitted to the study hospital. Patients were young (median age 32.5 years, range 12 - 53) and most were men (85%); 32 patients experienced blunt trauma, and 30 penetrating trauma. The median injury severity score was 18 (interquartile range [IQR] 9, 34), and 47% of patients had a brachial plexus injury. The arterial injury was occlusion in 62% of patients, and the median ischaemia time was 12.5 hours (IQR 7.13, 24). All patients with subclavian injuries (n = 37) and 13 of 25 patients with an axillary injury underwent endovascular repair (stent graft placement). Open repair was performed in 12 patients with axillary injury (axillobrachial bypass in seven patients). At hospital discharge, the amputation free survival rate was 82% vs. 92% (p = .67), the mortality rate was 10% vs. 8% (p = 1.0), and the amputation rate was 10% vs. 0 (p = .57) for endovascular and open repair, respectively. The mean follow up time was 4.1 +/- 3.5 years. After the seven year follow up, the stent primary patency was 42%. No re-interventions or amputations were performed after hospital discharge. Disability was related to fractures and soft tissue and brachial plexus injuries.Conclusion: Endovascular treatment was preferred for patients with subclavian artery injuries. Open repair was preferred for patients with penetrating axillary injuries. In hospital and long term complications were related to fractures and soft tissue and brachial plexus injuries, rather than the treatment of arterial injuries. Measures are needed to reduce ischaemia time and improve brachial plexus injury repair.