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1.
Ann Vasc Surg ; 102: 1-8, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38307228

RESUMO

BACKGROUND: Spontaneous isolated celiac artery dissection (SICAD) is uncommon, with very few series reported in the literature. The present study aims to describe the clinical characteristics and treatment outcomes of patients with SICAD treated at a single Chilean institution over 20 years. METHODS: A retrospective review of all patients from a single academic hospital with SICAD diagnosed between January 2003 and March 2023 was performed. Conservative treatment included antiplatelets, anticoagulation, or both. The normal size of a celiac artery in our population was 7.9 ± 0.79 mm in females and 8.3 ± 1.08 mm in males. We defined a celiac artery with a diameter equal to or more than 12.5 mm as an aneurysmal celiac artery. RESULTS: The cohort included 27 patients; 77.8% (n = 21) were males. The median age was 51.0 years (range: 38-84 years). Fourteen (51.8%) patients presented with aneurysmal dilatation. Fourteen (51.8%) patients were treated with antiplatelets, 6 (22.2%) patients with anticoagulation, and 7 (25.9%) with anticoagulation and antiplatelets. One patient was treated with endovascular therapy due to a pseudoaneurysm of the celiac artery detected 10 days after conservative treatment with antiplatelets. The median length of hospital stay was 5 days (range: 2-14 days). Complete remodeling was seen in 6 (22.2%) patients, partial remodeling in 10 (37.0%) patients, and no change was seen in 8 (26.9%) patients. Three (11.5%) patients were lost to follow-up. There were no significant differences between treatments and remodeling outcomes (P = 0.729). The median celiac artery diameter of patients with aneurysmal dilatation was 13.5 mm (range: 12.5-20.5 mm). Systemic arterial hypertension was found more commonly in patients who presented with aneurysmal dilatation than in patients without (87.5% vs. 12.5%, respectively, P = 0.016). Mean follow-up was 41.5 months and median follow-up was 16 months (range: 6-204 months). CONCLUSIONS: Most patients with SICAD can be treated conservatively with excellent outcomes. Hypertension was more commonly found in patients with SICAD and aneurysmal dilatation.


Assuntos
Dissecção Aórtica , Procedimentos Endovasculares , Hipertensão , Masculino , Feminino , Humanos , Pessoa de Meia-Idade , Artéria Celíaca/diagnóstico por imagem , Resultado do Tratamento , Procedimentos Endovasculares/efeitos adversos , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/terapia , Anticoagulantes/uso terapêutico , Estudos Retrospectivos
3.
Ann Vasc Surg ; 99: 193-200, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37805170

RESUMO

BACKGROUND: Infective native aortic aneurysms (INAAs), formerly called mycotic aneurysms, remain an uncommon disease with significant heterogeneity among cases; hence, there is lack of solid evidence to opt for the best treatment strategy. The present study aims to describe a 20-year experience at a single institution treating this uncommon condition. METHODS: Retrospective study of all patients treated for INAA at a single academic hospital in Santiago, Chile, between 2002 and 2022. Clinical characteristics are described, as well as operative outcomes per type of treatment. Nonparametric Mann-Whitney U-test or Kruskal-Wallis tests were performed when appropriate, and results were reported as median and ranges. Survival at given timeframes was determined by a Kaplan-Meier curve, with analysis performed through a Cox regression model. RESULTS: During the study period, 1,798 patients underwent aortic procedures at our center, of which 35 (1.9%) were treated for INAA. Of them, 25 (71.4%) were male. One patient had 2 INAAs. Median age was 69.5 years (range: 34-89 years). Of the 36 INAAs, the most frequent location was the abdominal and thoracic aorta in 20 (55.5%) and 11 (30.5%) cases, respectively, followed by the iliac arteries in 4 (11.1%) cases. One (2.7%) patient presented a thoracoabdominal INAA. Overall, endovascular treatment associated with long-term antibiotics was used in 20 (57.1%) patients: 4 of them underwent hybrid treatment. Fifteen (42.8%) patients underwent direct aortic debridement followed by in situ or extra anatomic revascularization. There was a significant difference in age between both treatment strategies (a median of 76.5 years for endovascular versus a median of 57 years for open, P = 0.011). The median hospital stay was 15 days (range: 2-70 days). The early complications rate (<30 postoperative days) was 20% (n = 7). Early mortality rate (inhospital or before postoperative 30 days) was 14.2% (n = 5). Median follow-up was 33 months (range: 6-216 months). The overall survival rates at 1, 3, and 5 years were 69.9% (standard error [SE] 8.0), 61.7% (SE 9.8), and 50.9% (SE 11.8), respectively. Five-year survival rate of patients undergoing endovascular treatment compared with open approach was 45.9% (SE 15.1) versus 80.0% (SE 17.8), respectively (P = 0.431). There were no significant differences in survival between open and endovascular treatment, hazard ratio 3.58 (confidence interval 95%: 0.185-1.968, SE ± 0.45 P = 0.454). CONCLUSIONS: Patients treated by endovascular approach were older than patients treated by open approach. Even though, the open group had a higher 5-year survival rate than the endovascular group, not statically significance differences were found between treatments.


Assuntos
Aneurisma Infectado , Aneurisma da Aorta Abdominal , Aneurisma da Aorta Torácica , Implante de Prótese Vascular , Procedimentos Endovasculares , Humanos , Masculino , Idoso , Feminino , Aneurisma Infectado/diagnóstico por imagem , Aneurisma Infectado/cirurgia , Chile , Estudos Retrospectivos , Resultado do Tratamento , Implante de Prótese Vascular/efeitos adversos , Procedimentos Endovasculares/efeitos adversos , Complicações Pós-Operatórias/etiologia , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/cirurgia , Aneurisma da Aorta Abdominal/etiologia , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/cirurgia , Aneurisma da Aorta Torácica/etiologia , Fatores de Risco
4.
J Vasc Surg Cases Innov Tech ; 9(3): 101290, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37662570

RESUMO

We report the case of a 60-year-old woman who sought medical attention for left cervical and supraclavicular pain and swelling. Previous computed tomography, intravascular ultrasound, and venography studies were reviewed, confirming extrinsic compression of the left innominate vein by the left common carotid artery against the left clavicle head. Stenting of the lesion was performed, with good mid-term symptom relief and patency. It is, to the best of our knowledge, the first case study in the literature to report endovascular treatment of this syndrome.

5.
Accid Anal Prev ; 191: 107222, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37515919

RESUMO

INTRODUCTION: The global motorcycle market has grown significantly, with over 770 million vehicles estimated to be in use worldwide. Motorcycle-related road traffic deaths in low and middle-income countries (LMICs) like Colombia are concerning, comprising 30% of all reported fatalities. Cartagena has an average of 70 motorcycle-related deaths annually between 2019 and 2022, making it a high-risk area for motorcyclists. OBJECTIVE: The study aimed to identify factors associated with motorcyclist safety at unsignalized three-legged and four-legged intersections in Cartagena by observing the behavior of the motorcyclists and the analysis of the potential traffic conflicts. The observational analysis focused on the access of motorcyclists from a secondary road to a main road since it is the behavior offered by the most significant road interaction and the potential risk of traffic conflicts due to crossing. METHODS: The observational process was consolidated at ten three-legged intersections and seven four-legged intersections. Thirty-six hours of videos were collected considering different time slots and weekdays randomly distributed during September 2019 and March 2020. The selection of the intersections included different vehicular flows and road safety conditions. The variables considered in the study were: interaction with other road users, motorcyclist behavior, vehicle handling, potential distractors, and safety elements. The study used the Swedish Traffic Conflict Technique to analyze conflict analysis, incorporating the Post Encroachment Time (PET) measurement. The analysis was developed with descriptive and inferential statistical techniques. The collected variables were analyzed individually (frequency analysis), and contrasts were conducted with the PET values. The study evaluated associations between motorcycles and other motorized road actors at intersections about behaviors and crossroads. RESULTS: In the Records, 10,281 motorcycle accesses at three and four-Legged Intersections were interactions with other road users, where 2417 and 1903 resulted in potential traffic conflicts, respectively. Average potential conflicts per hour were 115 and 127 at three and four-legged intersections. At the two intersections, the average PET values in motorcycles were between 2.09 and 2.10 s, while in the other motorized road users, it averaged around 2.67 to 2.71 s. In the road conditions, it was identified that intersections with a traffic flow of<10,000 vehicles/day and poor visibility to the left of the intersection lead to more unsafe conditions for motorcyclists. Motorcycle taxi drivers were the user group most frequently involved in traffic conflicts. Actions on the part of motorcyclists, such as risky behaviors, not using helmets, not using turn signals, and not waiting patiently for access, showed a relationship with the potential for traffic conflicts. Finally, turns to the left, particularly the indirect turn to the left on the opposite road, showed a greater risk of traffic conflicts. CONCLUSIONS: The study found that motorcycles exhibit more severe traffic conflicts than motorized vehicles at intersections. Infrastructure conditions significantly impact the risk of intersection conflicts. Individual behaviors such as not stopping at intersections and driving recklessly increased the risk of traffic conflicts. The study recommends improving infrastructure such as visibility and signaling and implementing separators to reduce travel speed and traffic conflicts for motorcycles.


Assuntos
Acidentes de Trânsito , Assunção de Riscos , Humanos , Acidentes de Trânsito/prevenção & controle , Colômbia , Motocicletas , Viagem
6.
Accid Anal Prev ; 190: 107180, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37356219

RESUMO

Contemporary research has pointed out that while newer cars are contributing to the decrease of AIS2+ and AIS3+ injuries in several body regions, this effect is not shown for thoracic injuries like rib or sternal fractures. The objective of this study is to assess the effectiveness of advanced seat belt systems incorporating pre-tensioners and load limiters in the prevention of fatal, AIS2+ and AIS3+ injuries overall and then focus only on the head-face-neck and thoracic areas. Data from the NASS CDS database between 2000 and 2015 was augmented with specific vehicle information taken from NHTSA's NCAP tests to identify the characteristics of the seat belt of each vehicle involved in a collision. Multivariate logistic regressions were developed to assess the likelihood of injuries for belted front seat occupants in frontal impacts. The presence of pre-tensioners and load limiters with a low load limiter (<4.5 kN) was significantly associated with a decreased risk of fatal and AIS3+ in the whole body (OR = 0.31 (p < 0.05) and OR = 0.70 (p < 0.1)), while high load limiters were significant in the prevention of fatal injuries (OR = 0.42). These effects should be considered always in combination with the delta-v of the collision, as the interaction term between delta-v and advanced seat belt features was significant. In the crashes considered, the model predicted a higher risk of injury for women compared to men, controlling for other occupant and crash factors. Impacts with a slightly oblique component increased the risk of injury compared to pure frontal impacts. After controlling for the presence of pre-tensioners and load limiters, the vehicle model year variable was found to be insignificant in any of the regression models. This study shows that the real-world effectiveness of advanced seat belts still requires further analysis. Other effects like age or impact direction might be more influential in the injury outcome than these seat belt features.


Assuntos
Traumatismos Torácicos , Ferimentos e Lesões , Masculino , Humanos , Feminino , Cintos de Segurança , Acidentes de Trânsito , Escala Resumida de Ferimentos , Automóveis , Traumatismos Torácicos/prevenção & controle , Ferimentos e Lesões/epidemiologia , Ferimentos e Lesões/prevenção & controle
7.
Front Bioeng Biotechnol ; 11: 1106554, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36860885

RESUMO

Introduction: Chest deformation has been proposed as the best predictor of thoracic injury risk in frontal impacts. Finite Element Human Body Models (FE-HBM) can enhance the results obtained in physical crash tests with Anthropometric Test Devices (ATD) since they can be exposed to omnidirectional impacts and their geometry can be modified to reflect specific population groups. This study aims to assess the sensitivity of two thoracic injury risk criteria (PC Score and Cmax) to several personalization techniques of FE-HBMs. Methods: Three 30° nearside oblique sled tests were reproduced using the SAFER HBM v8 and three personalization techniques were applied to this model to evaluate the influence on the risk of thoracic injuries. First, the overall mass of the model was adjusted to represent the weight of the subjects. Second, the model anthropometry and mass were modified to represent the characteristics of the post-mortem human subjects (PMHS). Finally, the spine alignment of the model was adapted to the PMHS posture at t = 0 ms, to conform to the angles between spinal landmarks measured in the PMHS. The following two metrics were used to predict three or more fractured ribs (AIS3+) of the SAFER HBM v8 and the effect of personalization techniques: the maximum posterior displacement of any studied chest point (Cmax), and the sum of the upper and lower deformation of selected rib points (PC score). Results: Despite having led to statistically significant differences in the probability of AIS3+ calculations, the mass-scaled and morphed version provided, in general, lower values for injury risk than the baseline model and the postured version being the latter, which exhibited the better approximation to the PMHS tests in terms of probability of injury. Additionally, this study found that the prediction of AIS3+ chest injuries based on PC Score resulted in higher probability values than the prediction based on Cmax for the loading conditions and personalization techniques analyzed within this study. Discussion: This study could demonstrate that the personalization techniques do not lead to linear trends when they are used in combination. Furthermore, the results included here suggest that these two criteria will result in significantly different predictions if the chest is loaded more asymmetrically.

8.
Materials (Basel) ; 16(4)2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36837267

RESUMO

Bone is a heterogeneous, hierarchical biocomposite material made of an organic matrix filled with a mineral component, which plays an important role in bone strength. Although the effect of the mineral/matrix ratio on the mechanical properties of bone during aging has been intensively investigated, the relationship between the mechanical properties and the chemical composition of bone with age requires additional research in juvenile individuals. In this study, bone coupons from bovine and ovine animal species were machined from cortical areas of long bones to quantify whether the variation in mechanical properties at different stages of development is related to the change in the composition of bone tissue. An energy-dispersive X-ray detector (EDX) attached to a scanning electron microscope (SEM) was used to perform a compositional analysis of the tissue. In addition, nanoindentation analyses were carried out to address how the elastic modulus changed with age. Nonparametric statistical analyses found significant differences (p < 0.05) in Ca content and elastic modulus between species, but no differences were found within each species with development. A multiple linear regression model found that the elastic modulus was significantly related to the decrease in P and C in the samples, to the animal species (larger in bovine), and development, although not linearly. This model also found an interaction between Ca and development that could explain the lack of significance of the relationship between the elastic modulus and development in the univariate models.

9.
Vascular ; 31(4): 813-817, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35392735

RESUMO

OBJECTIVE: This study aims to report two cases of symptomatic extrinsic compression of the inferior vena cava and left iliac vein caused by vertebral osteophytes. METHODS: We present two case reports of extrinsic venous compression by vertebral osteophytes. Both cases were endovascularly treated, with a successful outcome. A review of the literature of this unusual condition is also presented. RESULTS: The first patient is an 80-year-old woman who presented to the vascular surgery clinic with bilateral lower extremity edema and pain. A computed-tomography angiography (CTA) revealed extrinsic compression of the inferior vena cava from enlarged osteophytes. Venography and intravascular ultrasound were performed, confirming the diagnosis. A self-expanding venous stent was successfully deployed in the inferior vena cava relieving the extrinsic compression. The edema resolved the following day and was discharged without complications. The second patient is a 61-year-old male that presented to the emergency department with a left iliofemoral deep venous thrombosis. CTA showed left iliac vein compression by a lumbar osteophyte. Percutaneous thrombectomy was successfully achieved and an expanding stent was deployed covering the entire lesion. One month after the procedure the patient died from COVID-19-associated respiratory failure. CONCLUSION: Osteophytes must be considered when dealing with extrinsic venous compression, especially in elderly people.


Assuntos
COVID-19 , Osteófito , Doenças Vasculares , Trombose Venosa , Masculino , Feminino , Humanos , Idoso , Idoso de 80 Anos ou mais , Pessoa de Meia-Idade , Trombose Venosa/terapia , Veia Ilíaca , Veia Cava Inferior , Stents
10.
Traffic Inj Prev ; 24(1): 69-74, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36512330

RESUMO

Objective: The objective of this study is to analyze the 6 degrees of freedom (DOF) motion of the spine using the finite helical axis (FHA) in three postmortem human surrogates (PMHS) sled tests.Methods: The sled test configurations corresponded to a 30° nearside oblique impact at 35 km/h. Two different restraint system versions (RSv) were used. RSv1 was used for PMHS A and B while RSv2 was used for PMHS C. The 6 DOF motion of the head and three selected vertebrae have been analyzed using the FHA which describes the 3 D motion of a rigid body between two instants of time as a rotation about and a translation along a unit vector. A minimal amount of rotation is necessary to the FHA calculation, thus the FHA components have been calculated based on a pre-defined interval of 8° of rotation.Results: The analysis of the FHA components demonstrated right lateral bending until around 100 ms, when the rebound phase was reached and the head and the lower spine undergoes left lateral bending. The three PMHS exhibited, in general, flexion movement of the whole body and torsion to the right side of the occupant. This general motion can be associated to the effect of the seatbelt acting as a fulcrum of the rotational movement of the bony landmarks. The interaction of the PMHS with the retention system can be noted by analyzing the time in which the head and the upper spine initiated the rotation and the sudden changes of rotational direction of the three PMHS's head.Conclusions: The rotational analyses have shown to be more sensitive to experimental events than the trajectory analyses for the studied physical tests. Additionally, the results presented in the present study contributes to the analysis of the body kinematics during an oblique impact and adds new experimental data for Human Body Models (HBM) and Anthropometric Test Devices (ATD) benchmarking.


Assuntos
Aceleração , Acidentes de Trânsito , Humanos , Cadáver , Coluna Vertebral , Rotação , Fenômenos Biomecânicos
12.
J Vasc Bras ; 21: e20190160, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35677746

RESUMO

Endovascular embolization of arteries feeding pulmonary sequestrations is a growing therapeutic option. A 51-year-old woman with chest pain and hemoptysis was admitted. During hospitalization she presented 150 mL hemoptysis, hypotension, and hematocrit fell to 23.3%. Contrast-enhanced computed tomography confirmed a pulmonary sequestration irrigated by an aneurysmal artery from the abdominal aorta. The patient underwent endovascular coil embolization of the artery feeding the aneurysm and an Amplatzer device was deployed in the proximal third of the sequestration artery. Subsequent contrast-enhanced computed tomography confirmed complete thrombosis of the aberrant artery feeding the aneurysm and absence of irrigation of the pulmonary sequestration. At 56 months follow-up the patient remains asymptomatic, tomography showed involution of the sequestration and complete thrombosis of the aberrant artery. The challenges presented by the different treatment alternatives are discussed.


A embolização endovascular das artérias que alimentam os sequestros pulmonares é uma opção terapêutica em crescimento. Uma mulher de 51 anos com dor torácica e hemoptise foi internada. Durante a internação, ela apresentou hemoptise de 150 mL, hipotensão e queda do hematócrito para 23,3%. A tomografia computadorizada com contraste confirmou um sequestro pulmonar irrigado por uma artéria aneurismática originária da aorta abdominal. A paciente foi submetida a embolização endovascular da artéria que alimentava o aneurisma com uso de coils e dispositivo Amplatzer no terço proximal da artéria sequestrante. A tomografia subsequente confirmou a trombose completa da artéria aberrante que alimentava o aneurisma e a ausência de irrigação dentro do sequestro pulmonar. No seguimento de 56 meses, a paciente permanecia assintomática, e a tomografia mostrou involução do sequestro e trombose completa da artéria aberrante. Os desafios apresentados pelas diferentes alternativas de tratamento são discutidos neste artigo.

13.
Rev. med. Chile ; 150(6): 788-801, jun. 2022. tab
Artigo em Espanhol | LILACS | ID: biblio-1424138

RESUMO

Ruptured abdominal aortic aneurysm (RAAA) is an arterial emergency with an overall mortality of 80%-90% secondary to massive hemorrhage. If a patient with RAAA presents in a primary hospital without resolution capacity, survival will depend on early transfer to a center with adequately trained specialists. This article reviews the evidence supporting the centralization of AAAR treatment in qualified centers, specifying the criteria used for the selection of referral centers and the role of a coordinating unit. Our current referral system, which is based primarily on costs, is also described. Patients with AAAR who consult in non-resolving centers should be rapidly transferred to a qualified referral center, following a transfer protocol, and guided by a coordinating unit acting according to technical and established criteria based on results, quality, and costs. Qualified referral centers should have an accredited vascular surgeon and a high institutional aortic surgery volume, adequate infrastructure, endovascular resolution capacity, support services (intensive care, hemodialysis, etc.) and specialized personnel permanently available.


Assuntos
Humanos , Ruptura Aórtica/cirurgia , Aneurisma da Aorta Abdominal/cirurgia , Procedimentos Endovasculares/métodos , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento , Mortalidade Hospitalar , Hospitais
14.
Vasc Endovascular Surg ; : 15385744221098812, 2022 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-35506432

RESUMO

BACKGROUND: Innominate artery embolism may result in upper extremity ischemia or stroke. A free-floating thrombus originating from the IA is an unusual and dangerous disorder with embolic potential. Only isolated cases have been described showing different treatment modalities. PURPOSE: To present 3 cases of free-floating thrombus in the IA treated at our institution with 3 different approaches. CASES: The first case is a patient with a free-floating thrombus in the IA treated with cervical debranching and ligation of the proximal right carotid artery; another case of a patient treated with a hybrid approach with deployment of an iliac limb in the IA plus right carotid to subclavian bypass; and a third case of a patient operated by open arch thrombectomy. CONCLUSIONS: Free-floating thrombus in the IA is a threatening condition feasible to be managed through different customized surgical approaches in specialized centers.

15.
Vasc Endovascular Surg ; 56(6): 622-627, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35491900

RESUMO

Purpose: The objective of this study is to report a case of a 65-year-old woman who presented with pallor and pain of her left arm secondary to a true arterial brachial aneurysm, which was successfully treated with saphenous vein bypass and embolization of the aneurysm sac. A review of the literature is also presented. Case report: A 65-year-old woman presented with an acute onset of pallor and pain of her left forearm, and hand. On physical examination, there was a pulsatile mass at the forearm. A doppler ultrasound showed a fusiform aneurysmal dilatation of the brachial artery of 23 mm of diameter. A dynamic contrast-enhanced MRI angiogram confirmed a fusiform dilation of the distal brachial artery. The patient was scheduled for open repair. A fusiform 20 x 60 mm aneurysm of the distal brachial artery extending to the cubital fossa was found and a brachial artery to radial and ulnar arteries bypass with interposed reverse right saphenous vein was created. Embolization of the aneurysm sac was performed using Gelita-spon ® (Gelita Medical, Eberbach, Germany). A final angiogram showed an adequate perfusion through the bypass to the hand, and no contrast in the aneurysmal sac. Postoperative course was uneventful with discharge on the fourth postoperative day. Conclusion: Revascularization with autologous saphenous vein graft and exclusion of the aneurysm with local embolization is a good treatment alternative in a patient with symptomatic brachial aneurysm with distal embolization.


Assuntos
Aneurisma , Artéria Braquial , Idoso , Aneurisma/diagnóstico por imagem , Aneurisma/cirurgia , Artéria Braquial/diagnóstico por imagem , Artéria Braquial/cirurgia , Feminino , Humanos , Dor , Palidez/complicações , Veia Safena/diagnóstico por imagem , Veia Safena/transplante , Resultado do Tratamento
16.
Traffic Inj Prev ; 23(4): 181-186, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35201949

RESUMO

OBJECTIVE: The present study has three objectives: First, to analyze the chest deflection measured in nearside oblique tests performed with three post mortem human subjects (PMHS). Second, to assess the capability of a HBM to predict the chest deflection sustained by the PMHS. Third to evaluate the influence on chest deflection prediction of subject-specific HBM. METHODS: Three dimensional chest deformation of five anterior chest landmarks was extracted from three PMHS (A-C) in three sled tests. The sled test configurations corresponded to a 30 degree nearside oblique impact at 35 km/h. Two different restraint system versions (RSv) were used. RSv1 was used for PMHS A and B while RSv2 was used for PMHS C. The capability of the SAFER HBM (called baseline model) to predict PMHS chest deflection was benchmarked by means of the PMHS test results. In a second step, the anthropometry, mass and pre-impact posture of the baseline HBM were modified to the PMHS-specific characteristics to develop a model to assess the influence of personalization techniques in the capability of the human body model to predict PMHS chest deflection. RESULTS: In the sled tests, the measured sternum compression relative to the eighth thoracic vertebra in the PMHS tests was 49, 54 and 55 millimeters respectively. The HBM baseline model predicted 48%, 43% and 34% of the deflections measured in the PMHS tests, while the personalized version predicted 38%, 34% and 28%. When chest deflection was analyzed in x-, y- and z-direction for the five chest landmarks it was found that neither the baseline HBM nor the personalized model predicted x, y and z axis deflections. CONCLUSIONS: The PMHS in situ chest deflection was found to be sensitive to the variation in restraint system and the three PMHS exhibited greater values of lower right chest deflection compared to what was found in available literature. The baseline HBM underpredicted peak chest deflection obtained in the PMHS test. The personalized model was not capable of predicting the chest deflection sustained by the PMHS. Hence, further biofidelity investigations have to be carried out on the human body thorax model for oblique loading.


Assuntos
Acidentes de Trânsito , Corpo Humano , Fenômenos Biomecânicos , Cadáver , Humanos , Sujeitos da Pesquisa , Tórax
17.
Rev Med Chil ; 150(6): 788-801, 2022 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-37906914

RESUMO

Ruptured abdominal aortic aneurysm (RAAA) is an arterial emergency with an overall mortality of 80%-90% secondary to massive hemorrhage. If a patient with RAAA presents in a primary hospital without resolution capacity, survival will depend on early transfer to a center with adequately trained specialists. This article reviews the evidence supporting the centralization of AAAR treatment in qualified centers, specifying the criteria used for the selection of referral centers and the role of a coordinating unit. Our current referral system, which is based primarily on costs, is also described. Patients with AAAR who consult in non-resolving centers should be rapidly transferred to a qualified referral center, following a transfer protocol, and guided by a coordinating unit acting according to technical and established criteria based on results, quality, and costs. Qualified referral centers should have an accredited vascular surgeon and a high institutional aortic surgery volume, adequate infrastructure, endovascular resolution capacity, support services (intensive care, hemodialysis, etc.) and specialized personnel permanently available.


Assuntos
Aneurisma da Aorta Abdominal , Ruptura Aórtica , Procedimentos Endovasculares , Humanos , Ruptura Aórtica/cirurgia , Hospitais , Mortalidade Hospitalar , Aneurisma da Aorta Abdominal/cirurgia , Resultado do Tratamento , Procedimentos Endovasculares/métodos , Estudos Retrospectivos , Fatores de Risco
20.
Anticancer Agents Med Chem ; 22(7): 1414-1425, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34053425

RESUMO

BACKGROUND: Adenosine is a natural nucleoside present in a variety of organs and tissues, where it acts as a modulator of diverse physiological and pathophysiological processes. These actions are mediated by at least four G protein-coupled receptors, which are widely and differentially expressed in tissues. Interestingly, high concentrations of adenosine have been reported in a variety of tumors. In this context, the final output of adenosine in tumorigenesis will likely depend on the constellation of adenosine receptors expressed by tumor and stromal cells. Notably, activation of the A3 receptor can reduce the proliferative capacity of various cancer cells. OBJECTIVE: This study aimed to describe the anti-proliferative effects of two previously synthesized adenosine derivatives with A3 agonist action (compounds 2b and 2f) through in vitro assays. METHODS: We used gastric and breast cancer cell lines expressing the A3 receptor as in vitro models and theoretical experiments for molecular dynamics and determination of ADME properties. RESULTS: The antiproliferative effects of adenosine derivatives (after determining IC50 values) were comparable or even higher than those described for IB-MECA, a commercially available A3 agonist. Among possible mechanisms involved, apoptosis was found to be induced in MCF-7 cells but not in AGS or MDA-MB-231 cells. Surprisingly, we were unable to observe cellular senescence induction upon treatment with compounds 2b and 2f in any of the cell lines studied, although we cannot rule out other forms of cell cycles exit at this point. CONCLUSION: Both adenosine derivatives showed antiproliferative effects on gastric and breast cancer cell lines, and were able to induce apoptosis, at least in the MCF-7 cell line. Further studies will be necessary to unveil receptor specificity and mechanisms accounting for the antiproliferative properties of these novel semi-synthetic compounds.


Assuntos
Neoplasias da Mama , Receptor A3 de Adenosina , Adenosina/farmacologia , Apoptose , Neoplasias da Mama/tratamento farmacológico , Ciclo Celular , Feminino , Humanos , Receptor A3 de Adenosina/metabolismo
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