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1.
PLoS One ; 19(6): e0305089, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38923938

RESUMO

The volume of human carbon (δ13C) and nitrogen (δ15N) isotope data produced in archaeological research has increased markedly in recent years. However, knowledge of bone remodelling, its impact on isotope variation, and the temporal resolution of isotope data remains poorly understood. Varied remodelling rates mean different elements (e.g., femur and rib) produce different temporal signals but little research has examined intra-element variability. This study investigates human bone remodelling using osteon population density and the relationship with carbon and nitrogen isotope data at a high resolution, focusing on variation through femoral cross-sections, from periosteal to endosteal surfaces. Results demonstrate considerable differences in isotope values between cross-sectional segments of a single fragment, by up to 1.3‰ for carbon and 1.8‰ for nitrogen, illustrating the need for standardised sampling strategies. Remodelling also varies between bone sections, occurring predominantly within the endosteal portion, followed by the midcortical and periosteal. Therefore, the endosteal portion likely reflects a shorter period of life closer to the time of death, consistent with expectations. By contrast, the periosteal surface provides a longer average, though there were exceptions to this. Results revealed a weak negative correlation between osteon population density and δ15N or δ13C, confirming that remodelling has an effect on isotope values but is not the principal driver. However, a consistent elevation of δ15N and δ13C (0.5‰ average) was found between the endosteal and periosteal regions, which requires further investigation. These findings suggest that, with further research, there is potential for single bone fragments to reconstruct in-life dietary change and mobility, thus reducing destructive sampling.


Assuntos
Remodelação Óssea , Isótopos de Carbono , Fêmur , Isótopos de Nitrogênio , Humanos , Fêmur/anatomia & histologia , Fêmur/química , Fêmur/metabolismo , Remodelação Óssea/fisiologia , Isótopos de Carbono/análise , Isótopos de Nitrogênio/análise , Feminino , Masculino , Adulto , Pessoa de Meia-Idade
2.
J Cancer Surviv ; 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38649650

RESUMO

PURPOSE: Hodgkin lymphoma (HL) survivors are at increased risk of cardiovascular disease (CVD) due to former lymphoma treatment. In 2013, cardiovascular screening for 5-year HL survivors according to national guidelines was implemented in Dutch survivorship clinics. We aim to assess the following: (1) adherence to screening guidelines and (2) the yield of (risk factors for) CVD in the screening program. METHODS: The study population consisted of 5-year HL survivors who received survivorship care at three University Medical Centers from 2013 to 2016 through 2021. Patient characteristics, cardiovascular screening procedures, and outcomes were collected from the medical records. RESULTS: In 186 survivors eligible for cardiovascular screening (mean age 47.8 years, 60.8% female), the following diagnostics were performed: complete blood tests (81.0%, median frequency: yearly instead of advised 5-yearly evaluation), electrocardiogram (93.0%), echocardiography (94.6%). Fifty-five percent of survivors had at least one modifiable cardiovascular risk factor (i.e., current smoking, overweight, new/insufficiently controlled hypertension, dyslipidemia, or diabetes). Screening detected ≥ 1 CVD in 31.1% of survivors. Among survivors with available echocardiography report (n = 106), screening detected new aortic and/or mitral valve dysfunction(s) in 51.0% (with grades 3-4 in 4.9%) and impaired left ventricular ejection fraction in 10.3%. CONCLUSIONS: Adherence to the screening guidelines in the Dutch HL survivorship care program was reasonable to good and a substantial number of actionable (risk factors for) CVD were diagnosed. IMPLICATIONS FOR CANCER SURVIVORS: Our findings inform HL survivors at high risk of late cardiotoxicity about cardiovascular screening findings and demonstrate appropriate therapeutic actions after diagnosis of (risk factors for) CVD.

3.
JMIR Res Protoc ; 13: e55601, 2024 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-38635308

RESUMO

BACKGROUND: Hodgkin lymphoma (HL) occurs at young ages, with the highest incidence between 20 and 40 years. While cure rates have improved to 80%-90% over the past decades, survivors of HL are at substantial risk of late treatment-related complications, such as cardiovascular diseases, breast cancer, severe infections, and hypothyroidism. To reduce morbidity and mortality from late treatment effects, the Dutch Better care after lymphoma, Evaluation of long-term Treatment Effects and screening Recommendations (BETER) consortium developed a survivorship care program for 5-year survivors of HL that includes risk-based screening for and treatment of (risk factors for) late adverse events. Even though several cancer survivorship care programs have been established worldwide, there is a lack of knowledge about their effectiveness in clinical practice. OBJECTIVE: The Improving Nationwide Survivorship care Infrastructure and Guidelines after Hodgkin lymphoma Treatment (INSIGHT) study evaluates whether Dutch BETER survivorship care for survivors of HL decreases survivors' burden of disease from late adverse events after HL treatment and associated health care costs and improves their quality of life. METHODS: The INSIGHT study is a multicenter retrospective cohort study with a quasi-experimental design and prospective follow-up, embedded in the national BETER survivorship care infrastructure. The first BETER clinics started in 2013-2016 and several other centers started or will start BETER clinics in 2019-2024. This allows us to compare survivors who did and those who did not receive BETER survivorship care in the last decade. Survivors in the intervention group are matched to controls (n=450 per group) based on sex, age at diagnosis (±5 years), age in 2013 (±5 years), and treatment characteristics. The primary outcome is the burden of disease in disability-adjusted life years from cardiovascular disease, breast cancer, severe infections, and hypothyroidism. In a cost-effectiveness analysis, we will assess the cost of BETER survivorship care per averted or gained disability-adjusted life year and quality-adjusted life year. Secondary outcomes are BETER clinic attendance, adherence to screening guidelines, and knowledge and distress about late effects among survivors of HL. Study data are collected from a survivor survey, a general practitioner survey, medical records, and through linkages with national disease registries. RESULTS: The study was funded in November 2020 and approved by the institutional review board of the Netherlands Cancer Institute in July 2021. We expect to finalize recruitment by October 2024, data collection by early 2025, and data analysis by May 2025. CONCLUSIONS: INSIGHT is the first evaluation of a comprehensive survivorship program using real-world data; it will result in new information on the (cost-)effectiveness of survivorship care in survivors of HL in clinical practice. The results of this study will be used to improve the BETER program where necessary and contribute to more effective evidence-based long-term survivorship care for lymphoma survivors. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/55601.

4.
Arterioscler Thromb Vasc Biol ; 44(4): 976-986, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38328935

RESUMO

BACKGROUND: Plaque composition and wall shear stress (WSS) magnitude act as well-established players in coronary plaque progression. However, WSS magnitude per se does not completely capture the mechanical stimulus to which the endothelium is subjected, since endothelial cells experience changes in the WSS spatiotemporal configuration on the luminal surface. This study explores WSS profile and lipid content signatures of plaque progression to identify novel biomarkers of coronary atherosclerosis. METHODS: Thirty-seven patients with acute coronary syndrome underwent coronary computed tomography angiography, near-infrared spectroscopy intravascular ultrasound, and optical coherence tomography of at least 1 nonculprit vessel at baseline and 1-year follow-up. Baseline coronary artery geometries were reconstructed from intravascular ultrasound and coronary computed tomography angiography and combined with flow information to perform computational fluid dynamics simulations to assess the time-averaged WSS magnitude (TAWSS) and the variability in the contraction/expansion action exerted by WSS on the endothelium, quantifiable in terms of topological shear variation index (TSVI). Plaque progression was measured as intravascular ultrasound-derived percentage plaque atheroma volume change at 1-year follow-up. Plaque composition information was extracted from near-infrared spectroscopy and optical coherence tomography. RESULTS: Exposure to high TSVI and low TAWSS was associated with higher plaque progression (4.00±0.69% and 3.60±0.62%, respectively). Plaque composition acted synergistically with TSVI or TAWSS, resulting in the highest plaque progression (≥5.90%) at locations where lipid-rich plaque is exposed to high TSVI or low TAWSS. CONCLUSIONS: Luminal exposure to high TSVI, solely or combined with a lipid-rich plaque phenotype, is associated with enhanced plaque progression at 1-year follow-up. Where plaque progression occurred, low TAWSS was also observed. These findings suggest TSVI, in addition to low TAWSS, as a potential biomechanical predictor for plaque progression, showing promise for clinical translation to improve patient prognosis.


Assuntos
Doença da Artéria Coronariana , Placa Aterosclerótica , Humanos , Vasos Coronários/diagnóstico por imagem , Células Endoteliais , Doença da Artéria Coronariana/diagnóstico por imagem , Angiografia por Tomografia Computadorizada , Lipídeos , Estresse Mecânico , Angiografia Coronária
5.
Forensic Sci Int ; 358: 111745, 2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37301722

RESUMO

The location of human remains is performed primarily through the aid of cadaver detection dogs, which rely on the malodour produced through decomposition of decaying bodies. Malefactors will attempt to conceal these putrefactive odours through chemical additions such as lime, which is also wrongly believed to accelerate decomposition and prevent the identification of the victim. Despite the frequency of lime in forensic applications, to date no research has been performed to determine its effect on the volatile organic compounds (VOCs) released during human decomposition. This research was therefore conducted to ascertain the effects of hydrated lime on the VOC profile of human remains. Two human donors were used in a field trial at the Australian Facility for Taphonomic Experimental Research (AFTER): one donor was covered with hydrated lime, and the other had no chemical additions acting as a control. VOC samples were collected over a period of 100 days and analysed using comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry (GC×GC-TOFMS). The volatile samples were accompanied by visual observations of how decomposition progressed. The results showed that lime application decreased the rate of decomposition and decreased total carrion insect activity. Lime increased the abundance of VOCs during the fresh and bloat stages of decay, however the abundance of compounds plateaued during active and advanced decomposition and were much lower than those detected from the control donor. Despite this suppression of VOCs, the study found that dimethyl disulfide and dimethyl trisulfide, key sulfur-containing compounds, were still produced in high quantities, and can thus still be used to locate chemically altered human remains. Knowledge of the effects of lime on human decomposition can inform the training of cadaver detection dogs, and ensure a greater chance at locating victims of crimes or mass disasters.

6.
Cardiovasc Res ; 119(4): 1021-1029, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-36575921

RESUMO

AIMS: Low wall shear stress (WSS) is acknowledged to play a role in plaque development through its influence on local endothelial function. Also, lipid-rich plaques (LRPs) are associated with endothelial dysfunction. However, little is known about the interplay between WSS and the presence of lipids with respect to plaque progression. Therefore, we aimed to study the differences in WSS-related plaque progression between LRPs, non-LRPs, or plaque-free regions in human coronary arteries. METHODS AND RESULTS: In the present single-centre, prospective study, 40 patients who presented with an acute coronary syndrome successfully underwent near-infrared spectroscopy intravascular ultrasound (NIRS-IVUS) and optical coherence tomography (OCT) of at least one non-culprit vessel at baseline and completed a 1-year follow-up. WSS was computed applying computational fluid dynamics to a three-dimensional reconstruction of the coronary artery based on the fusion of the IVUS-segmented lumen with a CT-derived centreline, using invasive flow measurements as boundary conditions. For data analysis, each artery was divided into 1.5 mm/45° sectors. Plaque growth based on IVUS-derived percentage atheroma volume change was compared between LRPs, non-LRPs, and plaque-free wall segments, as assessed by both OCT and NIRS. Both NIRS- and OCT-detected lipid-rich sectors showed a significantly higher plaque progression than non-LRPs or plaque-free regions. Exposure to low WSS was associated with a higher plaque progression than exposure to mid or high WSS, even in the regions classified as a plaque-free wall. Furthermore, low WSS and the presence of lipids had a synergistic effect on plaque growth, resulting in the highest plaque progression in lipid-rich regions exposed to low shear stress. CONCLUSION: This study demonstrates that NIRS- and OCT-detected lipid-rich regions exposed to low WSS are subject to enhanced plaque growth over a 1-year follow-up. The presence of lipids and low WSS proves to have a synergistic effect on plaque growth.


Assuntos
Doença da Artéria Coronariana , Placa Aterosclerótica , Humanos , Vasos Coronários/diagnóstico por imagem , Doença da Artéria Coronariana/diagnóstico por imagem , Espectroscopia de Luz Próxima ao Infravermelho , Tomografia de Coerência Óptica , Estudos Prospectivos , Lipídeos
7.
EuroIntervention ; 18(3): 253-261, 2022 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34930718

RESUMO

BACKGROUND: Positive near-infrared spectroscopy (NIRS) signals might be encountered in areas without evident artery wall thickening, being typically perceived as artefacts. AIMS: We aimed to evaluate the utility of NIRS to identify artery wall regions associated with an increase in wall thickness (WT) as assessed by serial intravascular ultrasound (IVUS) and optical coherence tomography (OCT). METHODS: In this prospective, single-centre study, patients presenting with acute coronary syndrome (ACS) underwent NIRS-IVUS and OCT assessment of a non-culprit artery at baseline and 12-month follow-up. For each vessel, 1.5 mm segments were identified, matched and divided into 45 sectors. The relationship between the change in IVUS-based WT (DWT) and the presence of NIRS-positive signals and OCT-detected lipid was evaluated using linear mixed models. RESULTS: A total of 37 patients (38 vessels, 6,936 matched sectors) were analysed at baseline and 12 months. A total of 140/406 (34.5%) NIRS (+) sectors and 513/1,575 (32.6%) OCT-lipid (+) sectors were found to be located in thin (WT<0.5 mm) wall sectors. In the thin wall sectors, an increase in WT was significantly more pronounced in NIRS (+) vs NIRS (-) sectors (0.11 mm vs 0.06 mm, p<0.001). In the thick wall sectors, there was a decrease in WT observed that was less pronounced in the NIRS (+) versus NIRS (-) sectors (-0.08 mm vs -0.09 mm, p<0.001). Thin wall NIRS (+) OCT-lipid (+) sectors showed significant wall thickening (DWT=0.13 mm). CONCLUSIONS: NIRS-positive signals in otherwise non-diseased arterial walls as assessed by IVUS could identify vessel wall regions prone to WT increase over 12-month follow-up. Our observations suggest that NIRS-positive signals in areas without evident wall thickening by IVUS should no longer be viewed as benign or imaging artefact.


Assuntos
Doença da Artéria Coronariana , Placa Aterosclerótica , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Humanos , Lipídeos/análise , Placa Aterosclerótica/complicações , Placa Aterosclerótica/diagnóstico por imagem , Valor Preditivo dos Testes , Estudos Prospectivos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Tomografia de Coerência Óptica/métodos , Ultrassonografia de Intervenção/métodos
8.
Sci Rep ; 11(1): 22086, 2021 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-34764316

RESUMO

Wall shear stress (WSS), the frictional force of the blood on the vessel wall, plays a crucial role in atherosclerotic plaque development. Low WSS has been associated with plaque growth, however previous research used different approaches to define low WSS to investigate its effect on plaque progression. In this study, we used four methodologies to allocate low, mid and high WSS in one dataset of human coronary arteries and investigated the predictive power of low WSS for plaque progression. Coronary reconstructions were based on multimodality imaging, using intravascular ultrasound and CT-imaging. Vessel-specific flow was measured using Doppler wire and computational fluid dynamics was performed to calculate WSS. The absolute WSS range varied greatly between the coronary arteries. On the population level, the established pattern of most plaque progression at low WSS was apparent in all methodologies defining the WSS categories. However, for the individual patient, when using measured flow to determine WSS, the absolute WSS values range so widely, that the use of absolute thresholds to determine low WSS was not appropriate to identify regions at high risk for plaque progression.


Assuntos
Doença da Artéria Coronariana/patologia , Vasos Coronários/patologia , Placa Aterosclerótica/patologia , Idoso , Fenômenos Biomecânicos , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estresse Mecânico
9.
Front Bioeng Biotechnol ; 9: 731924, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34409022

RESUMO

Coronary atherosclerosis is a leading cause of illness and death in Western World and its mechanisms are still non completely understood. Several animal models have been used to 1) study coronary atherosclerosis natural history and 2) propose predictive tools for this disease, that is asymptomatic for a long time, aiming for a direct translation of their findings to human coronary arteries. Among them, swine models are largely used due to the observed anatomical and pathophysiological similarities to humans. However, a direct comparison between swine and human models in terms of coronary hemodynamics, known to influence atherosclerotic onset/development, is still lacking. In this context, we performed a detailed comparative analysis between swine- and human-specific computational hemodynamic models of coronary arteries. The analysis involved several near-wall and intravascular flow descriptors, previously emerged as markers of coronary atherosclerosis initiation/progression, as well as anatomical features. To do that, non-culprit coronary arteries (18 right-RCA, 18 left anterior descending-LAD, 13 left circumflex-LCX coronary artery) from patients presenting with acute coronary syndrome were imaged by intravascular ultrasound and coronary computed tomography angiography. Similarly, the three main coronary arteries of ten adult mini-pigs were also imaged (10 RCA, 10 LAD, 10 LCX). The geometries of the imaged coronary arteries were reconstructed (49 human, 30 swine), and computational fluid dynamic simulations were performed by imposing individualized boundary conditions. Overall, no relevant differences in 1) wall shear stress-based quantities, 2) intravascular hemodynamics (in terms of helical flow features), and 3) anatomical features emerged between human- and swine-specific models. The findings of this study strongly support the use of swine-specific computational models to study and characterize the hemodynamic features linked to coronary atherosclerosis, sustaining the reliability of their translation to human vascular disease.

10.
Curr Biol ; 31(11): 2455-2468.e18, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-33857427

RESUMO

The social organization of the first fully sedentary societies that emerged during the Neolithic period in Southwest Asia remains enigmatic,1 mainly because material culture studies provide limited insight into this issue. However, because Neolithic Anatolian communities often buried their dead beneath domestic buildings,2 household composition and social structure can be studied through these human remains. Here, we describe genetic relatedness among co-burials associated with domestic buildings in Neolithic Anatolia using 59 ancient genomes, including 22 new genomes from Asikli Höyük and Çatalhöyük. We infer pedigree relationships by simultaneously analyzing multiple types of information, including autosomal and X chromosome kinship coefficients, maternal markers, and radiocarbon dating. In two early Neolithic villages dating to the 9th and 8th millennia BCE, Asikli Höyük and Boncuklu, we discover that siblings and parent-offspring pairings were frequent within domestic structures, which provides the first direct indication of close genetic relationships among co-burials. In contrast, in the 7th millennium BCE sites of Çatalhöyük and Barcin, where we study subadults interred within and around houses, we find close genetic relatives to be rare. Hence, genetic relatedness may not have played a major role in the choice of burial location at these latter two sites, at least for subadults. This supports the hypothesis that in Çatalhöyük,3-5 and possibly in some other Neolithic communities, domestic structures may have served as burial location for social units incorporating biologically unrelated individuals. Our results underscore the diversity of kin structures in Neolithic communities during this important phase of sociocultural development.


Assuntos
Arqueologia , Estrutura Social , História Antiga , Humanos , Linhagem , Turquia
11.
J Cardiovasc Transl Res ; 14(5): 992-1000, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33624259

RESUMO

BACKGROUND: Coronary calcification has been linked to cardiovascular events. We developed and validated an algorithm to automatically quantify coronary calcifications on intravascular ultrasound (IVUS). We aimed to assess the prognostic value of an IVUS-calcium score (ICS) on patient-oriented composite endpoint (POCE). METHODS: We included patients that underwent coronary angiography plus pre-procedural IVUS imaging. The ICS was calculated per patient. The primary endpoint was a composite of all-cause mortality, stroke, myocardial infarction, and revascularization (POCE). RESULTS: In a cohort of 408 patients, median ICS was 85. Both an ICS ≥ 85 and a 100 unit increase in ICS increased the risk of POCE at 6-year follow-up (adjusted hazard ratio (aHR) 1.51, 95%CI 1.05-2.17, p value = 0.026, and aHR 1.21, 95%CI 1.04-1.41, p value = 0.014, respectively). CONCLUSIONS: The ICS, calculated by a validated automated algorithm derived from routine IVUS pullbacks, was strongly associated with the long-term risk of POCE.


Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Ultrassonografia de Intervenção , Calcificação Vascular/diagnóstico por imagem , Idoso , Automação , Angiografia Coronária , Doença da Artéria Coronariana/mortalidade , Doença da Artéria Coronariana/terapia , Progressão da Doença , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Revascularização Miocárdica , Valor Preditivo dos Testes , Prognóstico , Reprodutibilidade dos Testes , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Calcificação Vascular/mortalidade , Calcificação Vascular/terapia
12.
J Cardiovasc Transl Res ; 14(3): 416-425, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33034862

RESUMO

High wall shear stress (WSS) and near-infrared spectroscopy (NIRS) detected lipid-rich plaque (LRP) are both known to be associated with plaque destabilization and future adverse cardiovascular events. However, knowledge of spatial co-localization of LRP and high WSS is lacking. This study investigated the co-localization of LRP based on NIRS and high WSS. Fifty-three patients presenting acute coronary syndrome underwent NIRS-intravascular-ultrasound (NIRS-IVUS) imaging of a non-culprit coronary artery. WSS was obtained using WSS profiling in 3D-reconstructions of the coronary arteries based on fusion of IVUS-segmented lumen and CT-derived 3D-centerline. Thirty-eight vessels were available for final analysis and divided into 0.5 mm/45° sectors. LRP sectors, as identified by NIRS, were more often colocalized with high WSS than sectors without LRP. Moreover, there was a dose-dependent relationship between lipid content and high WSS exposure. This study is a first step in understanding the evolution of LRPs to vulnerable plaques. Graphical Abstract.


Assuntos
Síndrome Coronariana Aguda/diagnóstico por imagem , Doença da Artéria Coronariana/diagnóstico por imagem , Circulação Coronária , Vasos Coronários/diagnóstico por imagem , Hemodinâmica , Lipídeos/análise , Placa Aterosclerótica , Espectroscopia de Luz Próxima ao Infravermelho , Ultrassonografia de Intervenção , Síndrome Coronariana Aguda/metabolismo , Síndrome Coronariana Aguda/fisiopatologia , Idoso , Doença da Artéria Coronariana/metabolismo , Doença da Artéria Coronariana/fisiopatologia , Vasos Coronários/química , Vasos Coronários/fisiopatologia , Feminino , Humanos , Hidrodinâmica , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Modelos Cardiovasculares , Modelagem Computacional Específica para o Paciente , Valor Preditivo dos Testes , Estudos Prospectivos , Ruptura Espontânea , Estresse Mecânico
13.
Ann Biomed Eng ; 49(4): 1151-1168, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33067688

RESUMO

Endothelial shear stress (ESS) identifies coronary plaques at high risk for progression and/or rupture leading to a future acute coronary syndrome. In this study an optimized methodology was developed to derive ESS, pressure drop and oscillatory shear index using computational fluid dynamics (CFD) in 3D models of coronary arteries derived from non-invasive coronary computed tomography angiography (CTA). These CTA-based ESS calculations were compared to the ESS calculations using the gold standard with fusion of invasive imaging and CTA. In 14 patients paired patient-specific CFD models based on invasive and non-invasive imaging of the left anterior descending (LAD) coronary arteries were created. Ten patients were used to optimize the methodology, and four patients to test this methodology. Time-averaged ESS (TAESS) was calculated for both coronary models applying patient-specific physiological data available at the time of imaging. For data analysis, each 3D reconstructed coronary artery was divided into 2 mm segments and each segment was subdivided into 8 arcs (45°).TAESS and other hemodynamic parameters were averaged per segment as well as per arc. Furthermore, the paired segment- and arc-averaged TAESS were categorized into patient-specific tertiles (low, medium and high). In the ten LADs, used for optimization of the methodology, we found high correlations between invasively-derived and non-invasively-derived TAESS averaged over segments (n = 263, r = 0.86) as well as arcs (n = 2104, r = 0.85, p < 0.001). The correlation was also strong in the four testing-patients with r = 0.95 (n = 117 segments, p = 0.001) and r = 0.93 (n = 936 arcs, p = 0.001).There was an overall high concordance of 78% of the three TAESS categories comparing both methodologies using the segment- and 76% for the arc-averages in the first ten patients. This concordance was lower in the four testing patients (64 and 64% in segment- and arc-averaged TAESS). Although the correlation and concordance were high for both patient groups, the absolute TAESS values averaged per segment and arc were overestimated using non-invasive vs. invasive imaging [testing patients: TAESS segment: 30.1(17.1-83.8) vs. 15.8(8.8-63.4) and TAESS arc: 29.4(16.2-74.7) vs 15.0(8.9-57.4) p < 0.001]. We showed that our methodology can accurately assess the TAESS distribution non-invasively from CTA and demonstrated a good correlation with TAESS calculated using IVUS/OCT 3D reconstructed models.


Assuntos
Vasos Coronários/diagnóstico por imagem , Modelos Cardiovasculares , Modelagem Computacional Específica para o Paciente , Idoso , Angiografia por Tomografia Computadorizada , Vasos Coronários/fisiologia , Feminino , Humanos , Hidrodinâmica , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estresse Mecânico , Tomografia de Coerência Óptica , Ultrassonografia de Intervenção
14.
J Forensic Sci ; 66(2): 479-490, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33202037

RESUMO

Forensic investigations of single and mass graves often use surface anomalies, including changes to soil and vegetation conditions, to identify potential grave locations. Though numerous resources describe surface anomalies in grave detection, few studies formally investigate the rate at which the surface anomalies return to a natural state; hence, the period the grave is detectable to observers. Understanding these processes can provide guidance as to when ground searches will be an effective strategy for locating graves. We studied three experimental graves and control plots in woodland at the Australian Facility for Taphonomic Experimental Research (Sydney, Australia) to monitor the rate at which surface anomalies change following disturbance. After three years, vegetation cover on all grave sites and control plots had steadily increased but remained substantially less than undisturbed surroundings. Soil anomalies (depressions and cracking) were more pronounced at larger grave sites versus the smaller grave and controls, with leaf litterfall rendering smaller graves difficult to detect beyond 20 months. Similar results were observed in two concurrent burial studies, except where accelerated revegetation appeared to be influenced by mummified remains. Extreme weather events such as heatwaves and heavy rainfall may prolong the detection window for grave sites by hindering vegetation establishment. Observation of grave-indicator vegetation, which exhibited abnormally strong growth 10 months after commencement, suggests that different surface anomalies may have different detection windows. Our findings are environment-specific, but the concepts are applicable globally.

15.
Int J Cardiovasc Imaging ; 36(12): 2319-2333, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32779078

RESUMO

Improvements in spatial and temporal resolution now permit robust high quality characterization of presence, morphology and composition of coronary atherosclerosis in computed tomography (CT). These characteristics include high risk features such as large plaque volume, low CT attenuation, napkin-ring sign, spotty calcification and positive remodeling. Because of the high image quality, principles of patient-specific computational fluid dynamics modeling of blood flow through the coronary arteries can now be applied to CT and allow the calculation of local lesion-specific hemodynamics such as endothelial shear stress, fractional flow reserve and axial plaque stress. This review examines recent advances in coronary CT image-based computational modeling and discusses the opportunity to identify lesions at risk for rupture much earlier than today through the combination of anatomic and hemodynamic information.


Assuntos
Angiografia por Tomografia Computadorizada , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Modelos Cardiovasculares , Modelagem Computacional Específica para o Paciente , Animais , Tomada de Decisão Clínica , Doença da Artéria Coronariana/fisiopatologia , Doença da Artéria Coronariana/terapia , Circulação Coronária , Vasos Coronários/fisiopatologia , Hemodinâmica , Humanos , Hidrodinâmica , Valor Preditivo dos Testes , Prognóstico
16.
Ultrasound Med Biol ; 46(10): 2801-2809, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32636052

RESUMO

Coronary calcification represents a challenge in the treatment of coronary artery disease by stent placement. It negatively affects stent expansion and has been related to future adverse cardiac events. Intravascular ultrasound (IVUS) is known for its high sensitivity in detecting coronary calcification. At present, automated quantification of calcium as detected by IVUS is not available. For this reason, we developed and validated an optimized framework for accurate automated detection and quantification of calcified plaque in coronary atherosclerosis as seen by IVUS. Calcified lesions were detected by training a supported vector classifier per IVUS A-line on manually annotated IVUS images, followed by post-processing using regional information. We applied our framework to 35 IVUS pullbacks from each of the three commonly used IVUS systems. Cross-validation accuracy for each system was >0.9, and the testing accuracy was 0.87, 0.89 and 0.89 for the three systems. Using the detection result, we propose an IVUS calcium score, based on the fraction of calcium-positive A-lines in a pullback segment, to quantify the extent of calcified plaque. The high accuracy of the proposed classifier suggests that it may provide a robust and accurate tool to assess the presence and amount of coronary calcification and, thus, may play a role in image-guided coronary interventions.


Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Placa Aterosclerótica/diagnóstico por imagem , Ultrassonografia de Intervenção , Calcificação Vascular/diagnóstico por imagem , Automação , Humanos
17.
Proc Natl Acad Sci U S A ; 117(26): 14851-14856, 2020 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-32541036

RESUMO

The Mid-Upper Paleolithic (Gravettian) karstic Grotte de Cussac (France) contains two areas of human remains in the context of abundant (and spectacular) parietal engravings. The first area (loci 1 and 2) includes the skeleton of a young adult male in a bear nest, rearranged by postdecomposition inundation, and the variably fragmentary remains of at least two individuals distributed across two bear nests, sorted anatomically and with most of the elements constrained to one side of one nest. The second area (locus 3) retains remains of two adults and an adolescent, in upper hollows and variably distributed down the slope, largely segregated into upper versus lower body groups. The only decoration associated with the human remains is red pigment on some of the bones or underlying sediment. The human remains indicate variable nonnatural deposition and manipulation of human bodies, body portions, and skeletal elements of at least six individuals. Moreover, Cussac is unusual in the association of these remains with exceptional parietal art. The complex Cussac mortuary pattern joins growing evidence from other Gravettian sites of variable treatment of individuals after death, within and across sites, in terms of formal deposition of the body versus postmortem manipulation versus surface abandonment. It provides a window onto the social diversity and the complex interactions of the living and the dead among these successful Late Pleistocene foragers.


Assuntos
Sepultamento/história , Adulto , Animais , Arqueologia , Osso e Ossos/anatomia & histologia , Cavernas , França , História Antiga , Humanos , Masculino , Adulto Jovem
19.
J Forensic Leg Med ; 70: 101895, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31965971

RESUMO

The Murambi Genocide Memorial Centre is one of the major centres in Rwanda that commemorate the 1994 Rwandan genocide. Seventeen months after the genocide, about 1000 excavated human remains were put on display in Murambi Technical School. Repeated efforts were made to desiccate the human remains with lime for educational reasons. The aim of this study was to assess their state of preservation and understand the extent of degradation of the tissue. Limed soft tissue samples from four individuals were examined with light and electron microscopy, and subjected to histological analysis. Raman spectroscopy at 785 nm and 1064 nm provided information about the impact of environmental conditions on the extent of deterioration to these samples, the presence of organics and the conversion of the associated lime from calcium hydroxide to calcium carbonate. While visual degradation of the bodies in Murambi has been reported, this study confirms deterioration at a microscopic and molecular level. Both histology and Raman spectroscopic analysis revealed that the limed bodies in Murambi were deteriorating at the time the samples were collected. The results of this study will inform future decisions regarding the long-term conservation of those human remains.


Assuntos
Restos Mortais/diagnóstico por imagem , Compostos de Cálcio/química , Dessecação , Óxidos/química , Análise Espectral Raman , Restos Mortais/anatomia & histologia , Genocídio , Humanos , Ruanda/etnologia , Preservação de Tecido
20.
EuroIntervention ; 16(11): e930-e937, 2020 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31951204

RESUMO

AIMS: Bioresorbable scaffold (BRS) regions exposed to flow recirculation, low time-averaged wall shear stress (TAWSS) and high oscillatory shear index (OSI) develop increased neointima tissue. We investigated haemodynamic features in four different BRSs. METHODS AND RESULTS: Fantom (strut height [SH] = 125 µm), Fantom Encore (SH = 98 µm), Absorb (SH = 157 µm) and Magmaris (SH = 150 µm) BRSs were deployed in phantom tubes and imaged with microCT. Both 2D and 3D geometrical scaffold models were reconstructed. Computational fluid dynamics (CFD) simulation was performed to compute TAWSS and OSI. Thicker struts had larger recirculation zones and lower TAWSS in 2D. Absorb had the largest recirculation zone and the lowest TAWSS (240 µm and -0.18 Pa), followed by Magmaris (170 µm and -0.15 Pa), Fantom (140 µm and -0.14 Pa) and Fantom Encore (100 µm and -0.13 Pa). Besides strut size, stent design played a dominant role in 3D. The highest percentage area adverse TAWSS (<0.5 Pa) and OSI (>0.2) were found for Fantom (56% and 30%) and Absorb (53% and 33%), followed by Fantom Encore (30% and 25%) and Magmaris (25% and 20%). Magmaris had the smallest areas due to a small footprint and rounded struts. CONCLUSIONS: Due to stent design, both Fantom Encore and Magmaris showed smaller TAWSS and OSI than Fantom and Absorb. This study quantifies which scaffold features are most important to reduce long-term restenosis.


Assuntos
Implantes Absorvíveis , Hidrodinâmica , Simulação por Computador , Circulação Coronária , Vasos Coronários , Hemodinâmica , Modelos Cardiovasculares , Estresse Mecânico
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