RESUMO
INTRODUCTION: Medical improvements are needed to prevent ischemia-reperfusion injury in thoracoabdominal aortic surgery. The aim of this study was to determine the antioxidant effects of thymoquinone, silymarin, and curcumin against ischemia-reperfusion injury associated with abdominal aorta. METHODS: Twenty-five Wistar albino rats were included in the study. Sham, control, and treatment (thymoquinone, silymarin, and curcumin) groups were set in equal numbers. Ischemia-reperfusion was applied by clamping (120 minutes) and de-clamping (60 minutes) the infrarenal aorta of all groups, except the sham group. Before reperfusion, thymoquinone, silymarin, and curcumin were given intraperitoneally to the treatment groups. After reperfusion, blood samples were taken from the right ventricle. Total antioxidant status (TAS), total oxidant status (TOS), and oxidative stress index (OSI) were studied in serum samples and histopathological examination was performed on the gastrocnemius muscle. RESULTS: There was a significant difference in TOS and OSI values between the control and sham groups. Both values were found higher in the control group than in the sham group (P<0.05). OSI values were found to be lower in the thymoquinone group compared to the control group (P<0.05). All three parameters were found to be lower in the silymarin group than in the control group (P<0.05). TAS and TOS levels were found to be higher in the curcumin group than in the control group (P<0.05). There was no histopathological difference between the groups. CONCLUSION: Silymarin and thymoquinone administration decreases oxidative stress in experimental aortic ischemia-reperfusion injury. Antioxidant effect of curcumin was lower than silymarin and thymoquinone.
Assuntos
Curcumina , Traumatismo por Reperfusão , Silimarina , Animais , Ratos , Antioxidantes/farmacologia , Silimarina/farmacologia , Curcumina/farmacologia , Ratos Wistar , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/prevenção & controle , Traumatismo por Reperfusão/patologia , Isquemia , Aorta Abdominal/patologia , ReperfusãoRESUMO
Abdominal aortic aneurysms (AAAs) are a dangerous cardiovascular disease, the pathogenesis of which is not yet fully understood. In the present work a recent mechanopathological theory, which correlates AAA progression with microstructural and mechanical alterations in the tissue, is investigated using multiscale models. The goal is to combine these changes, within the framework of mechanobiology, with possible mechanical cues that are sensed by vascular cells along the AAA pathogenesis. Particular attention is paid to the formation of a 'neo-adventitia' on the abluminal side of the aortic wall, which is characterized by a highly random (isotropic) distribution of collagen fibers. Macro- and micro-scale results suggest that the formation of an AAA, as expected, perturbs the micromechanical state of the aortic tissue and triggers a growth and remodeling (G&R) reaction by mechanosensing cells such as fibroblasts. This G&R then leads to the formation of a thick neo-adventitia that appears to bring the micromechanical state of the tissue closer to the original homeostatic level. In this context, this new layer could act like a protective sheath, similar to the tunica adventitia in healthy aortas. This potential 'attempt at healing' by vascular cells would have important implications on the stability of the AAA wall and thus on the risk of rupture. STATEMENT OF SIGNIFICANCE: Current clinical criteria for risk assessment in AAAs are still empirical, as the causes and mechanisms of the disease are not yet fully understood. The strength of the arterial tissue is closely related to its microstructure, which in turn is remodeled by mechanosensing cells in the course of the disease. In this study, multiscale simulations show a possible connection between mechanical cues at the microscopic level and collagen G&R in AAA tissue. It should be emphasized that these micromechanical cues cannot be visualized in vivo. Therefore, the results presented here will help to advance our current understanding of the disease and motivate future experimental studies, with important implications for AAA risk assessment.
Assuntos
Aneurisma da Aorta Abdominal , Túnica Adventícia/patologia , Aorta , Aorta Abdominal/patologia , Aneurisma da Aorta Abdominal/patologia , Colágeno , HumanosRESUMO
Abstract Background Aneurysms and atheromatous processes are prominent pathological features that are commonly associated with significant morbidity and mortality. Objectives This cadaveric study was conducted to evaluate the morphometric and histological aspects of atheromatous plaque formation in abdominal aortas and their branches and their associated morphological variations, if present, characterized by loops, kinking, or tortuosity. Methods The study was performed using 30 human cadavers (approx. 65-75 years). Frequency of occurrence of calcified plaques in the abdominal aorta and its branches and their morphometric measurements were noted and histological features were observed with the aid of Hematoxylin & Eosin staining. Results Variations in the abdominal aorta and the common iliac artery were observed in 16.6% of specimens. Atheromatous plaque formation was seen in 2 specimens (1 specimen was associated with kinking) while in 3 other specimens only variation in normal structure (kinking/ tortuous artery) was observed. Histological analysis showed foamy macrophages and dense calcification, giving an atheromatous appearance. Conclusions Cadaveric reports of the location, nature, and degree of plaque formation in the abdominal aorta and its branches are extremely important in clinical settings and for choosing treatment options.
Resumo Contexto Aneurismas e processos ateromatosos são características patológicas perceptíveis que costumam estar associadas a morbidade e mortalidade significativas. Objetivos Este estudo em cadáveres teve como objetivo avaliar os aspectos morfométricos e histológicos da formação de placa ateromatosa na aorta abdominal e em seus ramos com suas subsequentes variações morfológicas caracterizadas por enrolamentos, acotovelamentos ou tortuosidades, se presentes. Métodos O estudo foi realizado com 30 cadáveres humanos (aproximadamente 65-75 anos). Foi descrita a frequência de ocorrência de placas calcificadas na aorta abdominal e em seus ramos com as respectivas medidas morfométricas e características histológicas com auxílio da coloração por hematoxilina e eosina. Resultados Variações na aorta abdominal e na artéria ilíaca comum foram observadas em 16,6% dos espécimes. A formação de placa ateromatosa foi observada em dois espécimes (um espécime foi associado a acotovelamento), enquanto em outros três espécimes houve apenas variação na estrutura normal (acotovelamento/artéria tortuosa). A análise histológica mostrou macrófagos espumosos e calcificação densa, o que gerou uma impressão ateromatosa. Conclusões Os estudos em cadáveres sobre localização, natureza e grau de formação de placa na aorta abdominal e em seus ramos são extremamente importantes para os cenários clínicos e as opções de tratamento.
Assuntos
Humanos , Masculino , Idoso , Aorta Abdominal/anatomia & histologia , Placa Aterosclerótica/epidemiologia , Aorta Abdominal/patologia , Prevalência , Placa Aterosclerótica/patologia , Artéria Ilíaca/anatomia & histologia , Artéria Ilíaca/patologiaRESUMO
Complete surgical resection of soft-tissue sarcomas (STSs) frequently requires complex multivisceral resections, which is the most important factor related to overall survival and local recurrence. Major vascular involvement is not rare in patients with primary retroperitoneal STSs. We present a 54-year-old woman with a retroperitoneal STS encasing the infrarenal abdominal aorta. The patient underwent complete oncological resection with vascular reconstruction using a bi-iliac vascular graft. Major blood vessel involvement is not a contraindication for STS surgery with a curative intent.
Assuntos
Aorta Abdominal/patologia , Neoplasias Retroperitoneais/cirurgia , Sarcoma/cirurgia , Aorta Abdominal/diagnóstico por imagem , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Retroperitoneais/diagnóstico por imagem , Neoplasias Retroperitoneais/patologia , Sarcoma/diagnóstico por imagem , Sarcoma/patologia , Tomografia Computadorizada por Raios XRESUMO
BACKGROUND: Several studies in the literature report continued proximal aorta and distal iliac artery dilatation after surgical correction of an abdominal aortic aneurysm (AAA). The purpose of this study is to evaluate these findings, in a South American population, and relate them to the type of configuration of the open procedure aortic reconstruction. METHODS: This is a retrospective review of ultrasonographic follow-up of patients submitted to open repair of AAA from 1989 to 2013, reporting proximal aorta dilatation (≥3 cm) and distal iliac artery dilatation (≥1.5 cm). RESULTS: A total of 155 patients were included. Life-table freedom at the intervals 11 < 15 years and ≥15 years were 47% and 23% for proximal dilatation and 63% and 38% for distal iliac arteries dilatation, respectively. There were more proximal and distal dilatations in patients submitted to more extensive aortic reconstructions (aorto-aortic 13% and 22% vs aorto-bilateral common iliacs 27% and 8% vs aorto-unilateral or bilateral external iliacs 27% and 32% and aorto-femoral 67% and 0%) P < 0.0001. Juxtarenal anastomosis was also correlated with more proximal dilatations (42% vs 21%, P = 0,046). There were two proximal and three distal anastomosis pseudoaneurysms. CONCLUSIONS: The presence of more extensive degenerative disease at the time of operation, requiring juxtarenal or more distal iliac reconstructions, may pose an increased risk of proximal aorta and iliac artery dilatation during follow-up. This study corroborates that significant changes are found after 7 to 10 years of the operation, reinforcing the need for long-term monitoring.
Assuntos
Falso Aneurisma/patologia , Aorta Abdominal/cirurgia , Aneurisma da Aorta Abdominal/cirurgia , Aneurisma Aórtico/patologia , Implante de Prótese Vascular/efeitos adversos , Artéria Ilíaca/cirurgia , Remodelação Vascular , Idoso , Idoso de 80 Anos ou mais , Falso Aneurisma/diagnóstico por imagem , Falso Aneurisma/epidemiologia , Aorta Abdominal/diagnóstico por imagem , Aorta Abdominal/patologia , Aneurisma Aórtico/diagnóstico por imagem , Aneurisma Aórtico/epidemiologia , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/epidemiologia , Aneurisma da Aorta Abdominal/patologia , Brasil/epidemiologia , Dilatação Patológica , Feminino , Humanos , Artéria Ilíaca/diagnóstico por imagem , Artéria Ilíaca/patologia , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do TratamentoRESUMO
OBJECTIVE: Tissue-engineered vascular grafts containing adipose-derived mesenchymal stem cells offer an alternative to small-diameter vascular grafts currently used in cardiac and lower-extremity revascularization procedures. Adipose-derived, mesenchymal stem cell-infused, tissue-engineered vascular grafts have been shown to promote remodeling and vascular homeostasis in vivo and offer a possible treatment solution for those with cardiovascular disease. Unfortunately, the time needed to cultivate adipose-derived mesenchymal stem cells remains a large hurdle for tissue-engineered vascular grafts as a treatment option. The purpose of this study was to determine if stromal vascular fraction (known to contain progenitor cells) seeded tissue-engineered vascular grafts would remain patent in vivo and remodel, allowing for a "same-day" process for tissue-engineered vascular graft fabrication and implantation. METHODS: Stromal vascular fraction, obtained from adult human adipose tissue, was seeded within 4 hours after acquisition from the patient onto poly(ester urethane)urea bilayered scaffolds using a customized rotational vacuum seeding device. Constructs were then surgically implanted as abdominal aortic interposition grafts in Lewis rats. RESULTS: Findings revealed patency in 5 of 7 implanted scaffolds at 8 weeks, along with neotissue formation and remodeling occurring in patent tissue-engineered vascular grafts. Patency was documented using angiography and gross inspection, and remodeling and vascular components were detected using immunofluorescent chemistry. CONCLUSIONS: A "same-day" cell-seeded, tissue-engineered vascular graft can remain patent after implantation in vivo, with neotissue formation and remodeling occurring by 8 weeks.
Assuntos
Tecido Adiposo/citologia , Aorta Abdominal/cirurgia , Bioprótese , Implante de Prótese Vascular/instrumentação , Prótese Vascular , Transplante de Células-Tronco/instrumentação , Células Estromais/fisiologia , Células Estromais/transplante , Engenharia Tecidual/métodos , Alicerces Teciduais , Adulto , Animais , Aorta Abdominal/metabolismo , Aorta Abdominal/patologia , Aorta Abdominal/fisiopatologia , Biomarcadores/metabolismo , Células Cultivadas , Estudos de Viabilidade , Feminino , Humanos , Pessoa de Meia-Idade , Neointima , Fenótipo , Desenho de Prótese , Ratos Endogâmicos Lew , Células Estromais/metabolismo , Fatores de Tempo , Transplante Heterólogo , Grau de Desobstrução Vascular , Remodelação Vascular , Fluxo de TrabalhoRESUMO
OBJECTIVE: The injury-reducing effect of acetaminophen, an effective analgesic and antipyretic on ischemia-reperfusion continues to attract great attention. This study analyzed the protective effect of acetaminophen on myocardial injury induced by ischemia-reperfusion in an experimental animal model from lower extremity ischemia-reperfusion. METHODS: Twenty-four Sprague-Dawley female rats were randomized into three groups (n=8) as (i) control group (only laparotomy), (ii) aortic ischemia-reperfusion group (60 min of ischemia and 120 min of reperfusion) and (iii) ischemia-reperfusion + acetaminophen group (15 mg/kg/h intravenous acetaminophen infusion starting 15 minutes before the end of the ischemic period and lasting till the end of the reperfusion period). Sternotomy was performed in all groups at the end of the reperfusion period and the heart was removed for histopathological examination. The removed hearts were histopathologically investigated for myocytolysis, polymorphonuclear leukocyte (PMNL) infiltration, myofibrillar edema and focal hemorrhage. RESULTS: The results of histopathological examination showed that acetaminophen was detected to particularly diminish focal hemorrhage and myofibrillar edema in the ischemia-reperfusion + acetaminophen group (P<0.001, P=0.011), while there were no effects on myocytolysis and PMNL infiltration between the groups (P=1.000, P=0.124). CONCLUSION: Acetaminophen is considered to have cardioprotective effect in rats, by reducing myocardial injury induced by abdominal aortic ischemia-reperfusion.
Assuntos
Acetaminofen/farmacologia , Cardiotônicos/farmacologia , Extremidade Inferior/irrigação sanguínea , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Animais , Aorta Abdominal/patologia , Constrição , Modelos Animais de Doenças , Edema Cardíaco/patologia , Feminino , Humanos , Isquemia/sangue , Isquemia/prevenção & controle , Traumatismo por Reperfusão Miocárdica/patologia , Miofibrilas/patologia , Distribuição Aleatória , Ratos Sprague-Dawley , Valores de Referência , Fatores de TempoRESUMO
Abstract Objective: The injury-reducing effect of acetaminophen, an effective analgesic and antipyretic on ischemia-reperfusion continues to attract great attention. This study analyzed the protective effect of acetaminophen on myocardial injury induced by ischemia-reperfusion in an experimental animal model from lower extremity ischemia-reperfusion. Methods: Twenty-four Sprague-Dawley female rats were randomized into three groups (n=8) as (i) control group (only laparotomy), (ii) aortic ischemia-reperfusion group (60 min of ischemia and 120 min of reperfusion) and (iii) ischemia-reperfusion + acetaminophen group (15 mg/kg/h intravenous acetaminophen infusion starting 15 minutes before the end of the ischemic period and lasting till the end of the reperfusion period). Sternotomy was performed in all groups at the end of the reperfusion period and the heart was removed for histopathological examination. The removed hearts were histopathologically investigated for myocytolysis, polymorphonuclear leukocyte (PMNL) infiltration, myofibrillar edema and focal hemorrhage. Results: The results of histopathological examination showed that acetaminophen was detected to particularly diminish focal hemorrhage and myofibrillar edema in the ischemia-reperfusion + acetaminophen group (P<0.001, P=0.011), while there were no effects on myocytolysis and PMNL infiltration between the groups (P=1.000, P=0.124). Conclusion: Acetaminophen is considered to have cardioprotective effect in rats, by reducing myocardial injury induced by abdominal aortic ischemia-reperfusion.
Assuntos
Humanos , Animais , Feminino , Cardiotônicos/farmacologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Extremidade Inferior/irrigação sanguínea , Acetaminofen/farmacologia , Aorta Abdominal/patologia , Valores de Referência , Fatores de Tempo , Traumatismo por Reperfusão Miocárdica/patologia , Distribuição Aleatória , Ratos Sprague-Dawley , Constrição , Modelos Animais de Doenças , Edema Cardíaco/patologia , Isquemia/prevenção & controle , Isquemia/sangue , Miofibrilas/patologiaRESUMO
OBJECTIVE: To investigate prevalence and predictors of cardiovascular risk in pediatric liver transplant recipients using noninvasive markers of subclinical atherosclerosis: carotid intima-media thickness (cIMT) and aorta intima-media thickness (aIMT). STUDY DESIGN: Cross-sectional study of 88 pediatric liver transplant recipients. The cIMT and aIMT were measured by ultrasound imaging using standardized protocol. RESULTS: Participants were 15.4 ± 4.8 years of age, and 11.2 ± 5.6 years post-transplantation. The cIMT and aIMT were both higher in males than females. In analyses adjusted for sex, age, and height, the cIMT was higher in subjects transplanted for chronic/cirrhotic liver disease and lower in subjects on cyclosporine (n = 9) than tacrolimus (n = 71). The cIMT was not associated with rejection history or current corticosteroid use. The cIMT increased with increasing diastolic blood pressure and triglycerides. The aIMT (n = 83) also increased with age, and its rate of increase post-transplant varied by age at transplantation. In adjusted analyses, aIMT was higher in subjects with glucose intolerance. In analysis of patients ≤20 years of age for whom blood pressure percentiles could be calculated (n = 66), aIMT increased with increasing diastolic blood pressure percentile (0.010 mm per 5-percentile; 95% CI, 0.000-0.021; P = 0.05). Neither the cIMT nor the aIMT was associated with obesity, systolic hypertension, or other dyslipidemia at study visit. CONCLUSION: Measures of long-term cardiovascular risk were associated with conditions that are more common in pediatric liver transplant recipients than nontransplanted peers, namely, diastolic hypertension and glucose intolerance. Larger, longitudinal studies are warranted to investigate whether cIMT could be useful for stratifying these patients' cardiovascular risk-and potential need for proactive intervention-during long-term follow-up.