VITOR CERVANTES GORNATI
Projetos de Pesquisa
Unidades Organizacionais
LIM/02 - Laboratório de Anatomia Médico-Cirúrgica, Hospital das Clínicas, Faculdade de Medicina
6 resultados
Resultados de Busca
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- Study of the Biomechanical and Histological Properties of the Abdominal Aorta of Diabetic Rats Exposed to Cigarette Smoke(2019) BARAO, Felipe Trajano de Freitas; BARAO, Vivian Helena Pedroso; GORNATI, Vitor Cervantes; SILVESTRE, Gina Camillo Rocha; SILVA, Alexandre Queiroz; LACCHINI, Silvia; CASTRO, Michele Mazzaron de; LUCCIA, Nelson De; SILVA, Erasmo Simao daIntroduction: In spite of the great relevance of abdominal aortic aneurysm, its etiopathogenesis is not fully understood. The biomechanical and histological study of the aortic wall may contribute to this elucidation. Methods: Seventy-five male Wistar rats were divided into 4 groups: control (CG), smoker (SG), diabetic (DG), and diabetic + smoker (DSG). The SG and DSG rats were exposed to cigarette smoke for 30 min/day, 5 days a week. Diabetes was induced by the intravenous injection of streptozotocin. After 16 weeks, the abdominal aorta was collected for biomechanical, histological, and matrix metalloproteinase 2 (MMP-2) activity analyses. Results: The valid biomechanical tests of 52 specimens were analyzed: 11 in the CG, 10 in the DG, 16 in the SG, and 15 in the DSG. The biomechanical analysis of the fragments showed no differences between the control, DG, SG, and DSG. Collagen deposition also did not present a significant difference between the studied groups. The total count of elastic fibers was higher in diabetic rats (DG and DSG) than in the SG. The inflammatory response observed in all experimental groups was significantly more intense than in the CG. Compared to the DSG, MMP-2 activity showed a significant decrease in the DG. Conclusions: Resistance and elasticity did not present a difference between the CG and the DG, SG, and DSG. Compared to the CG, the total count of elastic fibers, fragmentation of the elastic lamina, pericellular matrix deposition, and cell loss/substitution in the tunica media showed significant alterations in the aortic walls of the DG, SG, and DSG. MMP-2 activity was lower in the DG aorta than in the DSG aorta.
- The similarities and differences among patients with abdominal aortic aneurysms referred to a tertiary hospital and found at necropsy(2015) SILVA, Erasmo S. da; GORNATI, Vitor C.; CASELLA, Ivan B.; AUN, Ricardo; ESTENSSORO, Andre E. V.; PUECH-LEAO, Pedro; LUCCIA, Nelson DeObjective: To analyze the characteristics of patients with abdominal aortic aneurysms referred to a tertiary center and to compare with individuals with abdominal aortic aneurysm found at necropsy. Methods: We have retrospectively analyzed the medical records of 556 patients with abdominal aortic aneurysm and 102 cases abdominal aortic aneurysm found at necropsy. Results: At univariated analysis, hypertension, tobacco use and maximum diameter were significant risk factors for symptomatic aneurysm, while diabetes tended to be a protective factor for rupture. By logistic regression analysis, the largest transverse diameter was the only one significantly associated with abdominal aortic aneurysm rupture (p<.0001, odds ratio 1.7, 95% confidence interval 1.481-1.951). Intact abdominal aortic aneurysm found at necropsy showed similarities with outpatients in relation to abdominal aortic aneurysm diameter and risk factors. Conclusion: Intact abdominal aortic aneurysm at necropsy and at outpatients setting showed similarities that confirmed that abdominal aortic aneurysm repair is less offered to women, and they died more frequently with intact abdominal aortic aneurysm from other causes.
- Development of a Puncture Technique for Implanting Temporary Vascular Shunts in a Porcine Model(2019) GORNATI, Vitor Cervantes; UTSUNOMIA, Karen; LIMA, Thaissio Britto de; BARO, Felipe Trajano de Freitas; LOPES, Daniel Faccioli; SILVA, Erasmo Simao daBackground: Temporary vascular shunts (TVSs) are an effective tool for rapidly restoring blood flow to a limb or organ that has experienced vascular injury and ischemia and for which revascularization is not an immediate option. Usually, through an opening in the skin, the TVS is positioned within the proximal and distal stumps of the injured vessel, restoring perfusion and stopping the ischemia. The aim of this study is to compare standard TVS technique and a developed puncture technique for implanting TVS and to evaluate the utility and feasibility of this protocol after arterial lesions, in pigs. Methods: Vascular injuries were inflicted in both hind limbs of 30 pigs, and vascular interventions were performed, using standard and puncture TVS. Because each pig was implanted with both types of TVSs, it was possible to simultaneously monitor, analyze, and compare parameters such as, the mean arterial pressure (MAP, inmmHg), blood flow (mL/min), and insertion times, in the same animal. Results: It was observed that the MAP in the limbs recovered and approached systemic MAP, in 100% of the experiments, in both groups. Analysis of the blood flow data showed that this parameter was significantly reduced in the puncture TVS group (110.36 +/- 9.99 mL/min vs. 153.20 +/- 18.57 mL/min, P = 0.001). On the other hand, the insertion time for the standard TVS was significantly greater than that of the puncture shunt (15.32 +/- 3.08 min vs. 10.37 +/- 1.7 min, P = 0.001). Furthermore, it was found that the primary and secondary patency and complication rates were similar for both TVS types. Conclusion: Thus, given the adequate MAP recovery and reduction in implantation time observed in this experimental and in an animal model study, the use of the puncture TVS technique is effective and feasible.
- Normal Costoclavicular Distance as a Standard in the Radiological Evaluation of Thoracic Outlet Syndrome in the Costoclavicular Space(2021) DUARTE, Flavio H.; ZERATI, Antonio E.; GORNATI, Vitor C.; NOMURA, Cesar; PUECH-LEAO, PedroBackground: The costoclavicular space is a common site of thoracic outlet syndrome. When there is no anatomical alteration, the diagnosis of thoracic outlet syndrome is difficult. Several authors relate costoclavicular distance to symptoms of thoracic outlet syndrome; however, there is no standardized site for measurement of the costoclavicular distance. This study aimed to determine the standard costoclavicular distance at neurovascular bundle crossing points (near the subclavian vein [Measure V] and the subclavian artery/brachial plexus branches [Measure NA]) using high-resolution chest computed tomography (CT) scans and evaluate its variations with respect to age, sex, height, and body mass index. Methods: This prospective cross-sectional observational study analyzed 150 of 156 CT scans from consecutive adult patients (72 females and 78 males). Costoclavicular distance was measured at the subclavian vein and brachial plexus/subclavian artery sites, where narrowing of the costoclavicular distance could lead to symptoms of thoracic outlet syndrome. Costoclavicular distance was analyzed with respect to sex, laterality, age group (<50 and >50 years) and body mass index group (body mass index <25 and >25 kg/m2). Results: Measures of V and NA were normally distributed. The measured costoclavicular distances were 1.23 cm (+/- 0.40) and 1.24 cm (+/- 0.47), respectively. Age (>50 years) and body mass index (>25 kg/m2) increased the costoclavicular distance. Measurements V and NA below the fifth percentile indicated a narrowed costoclavicular distance and a greater chance of developing thoracic outlet syndrome. For young (<50 years) and eutrophic patients (body mass index <25 kg/m2), these measurements were 0.46 and 0.44 cm, respectively; for young people and body mass index >25 kg/m2, they were 0.54 and 0.24 cm, respectively; for the elderly (>50 years) and eutrophic, they were 0.57 and 0.48 cm, respectively; and for the elderly and body mass index > 25 kg/m2, they were 0.83 and 0.73 cm, respectively. There was no significant difference between measurements V and NA regarding patient laterality, gender, and height. Conclusions: Standardization of costoclavicular distance measurements at neurovascular bundle crossing points (subclavian vein and brachial plexus/subclavian artery) is possible. It may aid the diagnosis and help direct the therapeutic indications for symptomatic patients with thoracic outlet syndrome.
- A rare presentation of ruptured infected popliteal artery aneurysm with massive local emphysema(2015) GORNATI, Vitor Cervantes; SILVA, Erasmo Simao da; LUCCIA, Nelson De
- Histologic analysis of stent graft oversizing in the thoracic aorta(2013) SINCOS, Igor Rafael; SILVA, Erasmo Simao da; BELCZAK, Sergio Quilici; SINCOS, Anna Paula Weinhardt Baptista; HIGUCHI, Maria de Lourdes; GORNATI, Vitor; OTOCH, Jose Pinatas; AUN, RicardoObjective: To elucidate the histologic changes after stent graft oversizing in nonatherosclerotic aortas using an experimental porcine model. We previously reported that the diameter and angulation of the aorta in this model are similar to those in young individuals who undergo stent graft repair for blunt aortic injuries. The lack of commercially available stent grafts specific for repairing blunt aortic injuries, particularly for small and angulated aortas, may be related to the high rate of endograft complications in this population. Methods: Twenty-five pigs were randomized into one control group (without stent graft implantation) and four oversized groups (A: 10%-19%, B: 20%-29%, C: 30%-39%, and D: >40%). Three circumferential fragments were collected from the aorta for histologic and immunohistochemical studies. Morphometric analyzes were performed using an inflow system and image analysis software (Quantimet 500; Leica Cambridge Ltd, Cambridge, UK). Results: Collagen expression in the aortic wall was not significantly different among the five groups (P = .5604). There were significantly fewer muscle fibers in the aortic wall in the oversized groups compared with the control group (P = .000198). The proportion of elastic fibers in the aortic wall was significantly smaller in the oversized groups compared with the control group (P = .0000001). Immunohistochemical analysis showed that alpha-actin expression in the aortic wall was significantly decreased in the oversized groups compared with the control group (P= .002031). There were no significant differences in either the number of muscle fibers or alpha-actin expression among the four oversized groups. Conclusions: Histologic and immunohistochemical studies confirmed the structural disarrangement of the aortic wall after insertion of an endoprosthesis, including reduced number of muscle and elastic fibers.