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1.
BMC Cardiovasc Disord ; 22(1): 506, 2022 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-36435762

RESUMO

BACKGROUND: Studies have shown that quantitative evaluation of coronary artery plaque on Coronary Computed Tomography Angiography (CCTA) can identify patients at risk of cardiac events. Recent demonstration of artificial intelligence (AI) assisted CCTA shows that it allows for evaluation of CAD and plaque characteristics. Based on publications to date, we are the first group to perform AI augmented CCTA serial analysis of changes in coronary plaque characteristics over 13 years. We evaluated whether AI assisted CCTA can accurately assess changes in coronary plaque progression, which has potential clinical prognostic value in CAD management. CASE PRESENTATION: 51-year-old male with hypertension, hyperlipidemia and family history of myocardial infarction, underwent CCTA exams for anginal symptom evaluation and CAD assessment. 5 CCTAs were performed between 2008 and 2021. Quantitative atherosclerosis plaque characterization (APC) using an AI platform (Cleerly), was performed to assess CAD burden. Total plaque volume (TPV) change-over-time demonstrated decreasing low-density non-calcified plaque (LD-NCP) with increasing overall NCP and calcified-plaque (CP). Examination of individual segments revealed a proximal-LAD lesion with decreasing NCP over-time and increasing CP. In contrast, although the D2/D1/ramus lesions showed increasing stenosis, CP, and total plaque, there were no significant differences in NCP over-time, with stable NCP and increased CP. Remarkably, we also consistently visualized small plaques, which typically readers may interpret as false positives due to artifacts. But in this case, they reappeared each study in the same locations, generally progressing in size and demonstrating expected plaque transformation over-time. CONCLUSIONS: We performed the first AI augmented CCTA based serial analysis of changes in coronary plaque characteristics over 13 years. We were able to consistently assess progression of plaque volumes, stenosis, and APCs with this novel methodology. We found a significant increase in TPV composed of decreasing LD-NCP, and increasing NCP and CP, with variations in the evolution of APCs between vessels. Although the significance of evolving APCs needs to be investigated, this case demonstrates AI-based CCTA analysis can serve as valuable clinical tool to accurately define unique CAD characteristics over time. Prospective trails are needed to assess whether quantification of APCs provides prognostic capabilities to improve clinical care.


Assuntos
Doença da Artéria Coronariana , Placa Aterosclerótica , Masculino , Humanos , Pessoa de Meia-Idade , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/terapia , Angiografia por Tomografia Computadorizada , Angiografia Coronária/métodos , Inteligência Artificial , Estudos Prospectivos , Constrição Patológica
2.
Org Divers Evol ; 21(4): 691-717, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34658667

RESUMO

In the deep sea, the phylogeny and biogeography of only a few taxa have been well studied. Although more than 200 species in 32 genera have been described for the asellote isopod families Desmosomatidae Sars, 1897 and Nannoniscidae Hansen, 1916 from all ocean basins, their phylogenetic relationships are not completely understood. There is little doubt about the close relationship of these families, but the taxonomic position of a number of genera is so far unknown. Based on a combined morphological phylogeny using the Hennigian method with a dataset of 107 described species and a molecular phylogeny based on three markers (COI, 16S, and 18S) with 75 species (most new to science), we could separate Desmosomatidae and Nannoniscidae as separate families. However, we could not support the concept of the subfamilies Eugerdellatinae Hessler, 1970 and Desmosomatinae Hessler, 1970. Most genera of both families were well supported, but several genera appear as para- or even polyphyletic. Within both families, convergent evolution and analogies caused difficulty in defining apomorphies for phylogenetic reconstructions and this is reflected in the results of the concatenated molecular tree. There is no biogeographic pattern in the distribution as the genera occur over the entire Atlantic and Pacific Ocean, showing no specific phylogeographical pattern. Poor resolution at deep desmosomatid nodes may reflect the long evolutionary history of the family and rapid evolutionary radiations. Supplementary Information: The online version contains supplementary material available at 10.1007/s13127-021-00509-9.

4.
Scand Cardiovasc J ; 52(5): 262-267, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30182762

RESUMO

OBJECTIVES: An acute coronary occlusion and its possible subsequent complications is one of the most common causes of death. One such complication is ventricular fibrillation (VF) due to myocardial ischemia. The severity of ischemia is related to the amount of coronary arterial collateral flow. In dog studies collateral flow has also been shown to be associated with QRS prolongation. The aim of this study was to investigate whether ischemic QRS prolongation (IQP) is associated with impending VF in an experimental acute ischemia dog model. METHODS: Degree of IQP and occurrence of VF were measured in dogs (n = 21) during coronary occlusion for 15 min and also during subsequent reperfusion (experiments conducted in 1984). RESULTS: There was a significant difference in absolute IQP between dogs which developed VF during reperfusion (47 ± 29 ms, mean ± SD) and those which did not (12 ± 10 ms; p = .001). CONCLUSIONS: IQP during acute coronary occlusion is associated with reperfusion VF in an experimental dog model and might therefore be a potential predictor of malignant arrhythmias in patients with acute coronary syndrome.


Assuntos
Síndrome Coronariana Aguda/complicações , Oclusão Coronária/complicações , Sistema de Condução Cardíaco/fisiopatologia , Fibrilação Ventricular/etiologia , Potenciais de Ação , Síndrome Coronariana Aguda/diagnóstico por imagem , Síndrome Coronariana Aguda/fisiopatologia , Animais , Circulação Colateral , Circulação Coronária , Oclusão Coronária/diagnóstico , Oclusão Coronária/fisiopatologia , Modelos Animais de Doenças , Cães , Eletrocardiografia , Frequência Cardíaca , Fatores de Risco , Fatores de Tempo , Fibrilação Ventricular/diagnóstico , Fibrilação Ventricular/fisiopatologia
5.
J Arthroplasty ; 33(5): 1557-1561, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29352689

RESUMO

BACKGROUND: Navigated total hip arthroplasty (THA) can employ intra-osseous pins through a separate incision to secure reference arrays to the iliac crest. This study is the first to investigate the consequences of pin use in THA in vivo. METHODS: A prospective, consecutive series of 43 patients presenting for navigated THA were included. Two temporary 125 × 4 mm Schanz screws were inserted into the iliac crest for the attachment of a reference array. Telephone follow-up occurred at 6 and 12 weeks post-operatively. Patients were asked about pain, interference with daily activities, how often the wound was noticed, and duration of discomfort. Patient body mass index was recorded. RESULTS: The follow-up rate was 100%. Pin site pain at any time post-operatively was reported by 24 patients (56%). This improved to 30%, 9%, and 2% at 3, 6, and 12 weeks, respectively. On average, pain lasted for 16 days total. The most common complaints after pain were clothing discomfort (23%), pain when wearing a belt (12%), or pain when mobilizing (9%). For the majority (98%) of patients, all symptoms had resolved by 12 weeks. There was no nerve injury, pin site fracture, infection, or screw breakage. Patients with body mass index greater than 30 kg/m2 were up to 3 times more likely to experience pin site pain (P = .05), and had a longer duration of pain (P = .04). CONCLUSION: Surgeons and patients should be aware that using navigational pins for array fixation carries low complication rates but often will cause pain and irritation that resolves in the short term.


Assuntos
Artroplastia de Quadril/efeitos adversos , Pinos Ortopédicos , Parafusos Ósseos , Fraturas Ósseas/cirurgia , Ílio/cirurgia , Cirurgia Assistida por Computador , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Morbidade , Estudos Prospectivos , Adulto Jovem
6.
Circ Res ; 117(3): 254-65, 2015 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-25972514

RESUMO

RATIONALE: After acute myocardial infarction (MI), delineating the area-at-risk (AAR) is crucial for measuring how much, if any, ischemic myocardium has been salvaged. T2-weighted MRI is promoted as an excellent method to delineate the AAR. However, the evidence supporting the validity of this method to measure the AAR is indirect, and it has never been validated with direct anatomic measurements. OBJECTIVE: To determine whether T2-weighted MRI delineates the AAR. METHODS AND RESULTS: Twenty-one canines and 24 patients with acute MI were studied. We compared bright-blood and black-blood T2-weighted MRI with images of the AAR and MI by histopathology in canines and with MI by in vivo delayed-enhancement MRI in canines and patients. Abnormal regions on MRI and pathology were compared by (a) quantitative measurement of the transmural-extent of the abnormality and (b) picture matching of contours. We found no relationship between the transmural-extent of T2-hyperintense regions and that of the AAR (bright-blood-T2: r=0.06, P=0.69; black-blood-T2: r=0.01, P=0.97). Instead, there was a strong correlation with that of infarction (bright-blood-T2: r=0.94, P<0.0001; black-blood-T2: r=0.95, P<0.0001). Additionally, contour analysis demonstrated a fingerprint match of T2-hyperintense regions with the intricate contour of infarcted regions by delayed-enhancement MRI. Similarly, in patients there was a close correspondence between contours of T2-hyperintense and infarcted regions, and the transmural-extent of these regions were highly correlated (bright-blood-T2: r=0.82, P<0.0001; black-blood-T2: r=0.83, P<0.0001). CONCLUSION: T2-weighted MRI does not depict the AAR. Accordingly, T2-weighted MRI should not be used to measure myocardial salvage, either to inform patient management decisions or to evaluate novel therapies for acute MI.


Assuntos
Imageamento por Ressonância Magnética/métodos , Infarto do Miocárdio/patologia , Miocárdio/patologia , Adulto , Idoso , Animais , Circulação Coronária , Diagnóstico Diferencial , Cães , Edema/patologia , Determinação de Ponto Final , Feminino , Corantes Fluorescentes , Coração/fisiopatologia , Humanos , Masculino , Microesferas , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Infarto do Miocárdio/induzido quimicamente , Infarto do Miocárdio/fisiopatologia , Tamanho do Órgão , Compostos Organometálicos , Estudos Prospectivos , Risco , Troponina T/sangue
7.
Basic Res Cardiol ; 111(6): 70, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27766474

RESUMO

To commemorate the auspicious occasion of the 30th anniversary of IPC, leading pioneers in the field of cardioprotection gathered in Barcelona in May 2016 to review and discuss the history of IPC, its evolution to IPost and RIC, myocardial reperfusion injury as a therapeutic target, and future targets and strategies for cardioprotection. This article provides an overview of the major topics discussed at this special meeting and underscores the huge importance and impact, the discovery of IPC has made in the field of cardiovascular research.


Assuntos
Precondicionamento Isquêmico Miocárdico , Traumatismo por Reperfusão Miocárdica , Animais , Humanos
8.
J Electrocardiol ; 49(2): 139-47, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26810927

RESUMO

BACKGROUND: Previous studies have shown that QRS prolongation is a sign of depressed collateral flow and increased rate of myocardial cell death during coronary occlusion. The aims of this study were to evaluate ischemic QRS prolongation as a biomarker of severe ischemia by establishing the relationship between prolongation and collateral flow experimentally in a dog model, and test if the same pattern of ischemic QRS prolongation occurs in man. METHODS: Degree of ischemic QRS prolongation was measured using a novel method in dogs (n=23) and patients (n=52) during coronary occlusion for 5min. Collateral arterial flow was assessed in the dogs. RESULTS: There was a significant correlation between QRS prolongation and collateral flow in dogs (r=0.61, p=0.008). Magnitude and temporal evolution of prolongation during ischemia were similar for dogs and humans (p=0.202 and p=0.911). CONCLUSION: Quantification of ischemic QRS prolongation could potentially be used as a biomarker for severe myocardial ischemia.


Assuntos
Vasos Coronários/fisiopatologia , Diagnóstico por Computador/métodos , Eletrocardiografia/métodos , Isquemia Miocárdica/diagnóstico , Isquemia Miocárdica/fisiopatologia , Adulto , Idoso , Animais , Biomarcadores , Velocidade do Fluxo Sanguíneo , Circulação Coronária , Cães , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/classificação , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Especificidade da Espécie
9.
Biochim Biophys Acta ; 1837(6): 726-33, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24561096

RESUMO

The fluorescence emission characteristics of the photosynthetic apparatus under conditions of open (F0) and closed (FM) Photosystem II reaction centres have been investigated under steady state conditions and by monitoring the decay lifetimes of the excited state, in vivo, in the green alga Chlorella sorokiniana. The results indicate a marked wavelength dependence of the ratio of the variable fluorescence, FV=FM-F0, over FM, a parameter that is often employed to estimate the maximal quantum efficiency of Photosystem II. The maximal value of the FV/FM ratio is observed between 660 and 680nm and the minimal in the 690-730nm region. It is possible to attribute the spectral variation of FV/FM principally to the contribution of Photosystem I fluorescence emission at room temperature. Moreover, the analysis of the excited state lifetime at F0 and FM indicates only a small wavelength dependence of Photosystem II trapping efficiency in vivo.


Assuntos
Chlorella/metabolismo , Complexo de Proteína do Fotossistema II/metabolismo , Espectrometria de Fluorescência
10.
Plant Cell ; 24(7): 2963-78, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22822202

RESUMO

State transitions are an important photosynthetic short-term response that allows energy distribution balancing between photosystems I (PSI) and II (PSII). In plants when PSII is preferentially excited compared with PSI (State II), part of the major light-harvesting complex LHCII migrates to PSI to form a PSI-LHCII supercomplex. So far, little is known about this complex, mainly due to purification problems. Here, a stable PSI-LHCII supercomplex is purified from Arabidopsis thaliana and maize (Zea mays) plants. It is demonstrated that LHCIIs loosely bound to PSII in State I are the trimers mainly involved in state transitions and become strongly bound to PSI in State II. Specific Lhcb1-3 isoforms are differently represented in the mobile LHCII compared with S and M trimers. Fluorescence analyses indicate that excitation energy migration from mobile LHCII to PSI is rapid and efficient, and the quantum yield of photochemical conversion of PSI-LHCII is substantially unaffected with respect to PSI, despite a sizable increase of the antenna size. An updated PSI-LHCII structural model suggests that the low-energy chlorophylls 611 and 612 in LHCII interact with the chlorophyll 11145 at the interface of PSI. In contrast with the common opinion, we suggest that the mobile pool of LHCII may be considered an intimate part of the PSI antenna system that is displaced to PSII in State I.


Assuntos
Arabidopsis/química , Complexos de Proteínas Captadores de Luz/química , Complexo de Proteína do Fotossistema I/química , Complexo de Proteína do Fotossistema II/metabolismo , Tilacoides/química , Zea mays/química , Arabidopsis/metabolismo , Clorofila/metabolismo , Dicroísmo Circular , Transferência de Energia , Complexos de Proteínas Captadores de Luz/isolamento & purificação , Complexos de Proteínas Captadores de Luz/metabolismo , Complexos de Proteínas Captadores de Luz/ultraestrutura , Espectrometria de Massas , Modelos Químicos , Complexo de Proteína do Fotossistema I/isolamento & purificação , Complexo de Proteína do Fotossistema I/metabolismo , Complexo de Proteína do Fotossistema I/ultraestrutura , Isoformas de Proteínas , Multimerização Proteica , Estabilidade Proteica , Espectrometria de Fluorescência , Tilacoides/metabolismo , Zea mays/metabolismo
11.
Circ Res ; 113(4): 428-38, 2013 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-23908330

RESUMO

A selective history of the pathophysiological, structural, and metabolic changes found during an episode of severe myocardial ischemia in the canine heart is presented. The changes that cause ischemic injury to become irreversible are discussed in detail because these changes are the target of any successful therapy designed to prevent ischemic cell death. Of these, the disruption of the sarcolemma, an injury the development of which is accelerated in vivo by the contraction of viable tissue elsewhere in the heart traumatizing the ischemic area, plus the changes in high-energy phosphate and the total adenine nucleotide pool are considered to be the critical events leading to the development of irreversibility. The discovery of preconditioning with ischemia is discussed, together with a brief description of postconditioning. Finally, reperfusion injury is discussed in a summary fashion. The evidence for the fact that myocytes are salvaged by reperfusion is presented, as is the evidence that myocytes become unsalvageable by reperfusion as the duration of ischemia increases. The concept that some of the myocytes that die after successful reperfusion with arterial blood actually are killed by changes initiated by reperfusion, so-called lethal reperfusion injury, is attractive in that prevention of this change would lead to greater salvage; however, the prevalence of this phenomenon in clinical practice remains to be determined.


Assuntos
Modelos Animais de Doenças , Traumatismo por Reperfusão Miocárdica/história , Traumatismo por Reperfusão Miocárdica/patologia , Miócitos Cardíacos/patologia , Nucleotídeos de Adenina/fisiologia , Animais , Morte Celular/fisiologia , Cães , História do Século XIX , História do Século XX , História do Século XXI , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Miócitos Cardíacos/fisiologia , Fosfatos/fisiologia , Fatores de Tempo
12.
Biochim Biophys Acta ; 1827(6): 779-85, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23542448

RESUMO

In the present paper the marked changes in photochemical trapping time over the absorption/fluorescence band of isolated PSI-LHCI are studied by means of time resolved fluorescence decay measurements. For emission at 680-690nm the effective trapping time is close to 17-18ps, and represents the effective trapping time from the bulk antenna. At wavelengths above 700nm the effective trapping time increases in a monotonic way, over the entire emission band, to attain values in the range of 70-80ps near 760nm. This is argued to be caused by "uphill" energy transfer from the low energy states to the core antenna and reaction centre. These data, together with the steady state emission spectrum, permit calculation of the overall trapping time for maize PSI-LHCI, which is estimated to be approximately 40ps. The wavelength dependence of the trapping time indicates, that in PSI-LHCI there exists at least one red form which emits at lower energies than the 735nm state. These data indicate that Photosystem I is about 55% diffusion limited.


Assuntos
Complexo de Proteína do Fotossistema I/química , Zea mays/metabolismo , Clorofila/química , Fluorescência , Fotoquímica
13.
Am J Physiol Heart Circ Physiol ; 307(1): H80-7, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24778173

RESUMO

Ischemic preconditioning is a form of intrinsic cardioprotection where an episode of sublethal ischemia protects against subsequent episodes of ischemia. Identifying a clinical biomarker of preconditioning could have important clinical implications, and prior work has focused on the electrocardiographic ST segment. However, the electrophysiology biomarker of preconditioning is increased action potential duration (APD) shortening with subsequent ischemic episodes, and APD shortening should primarily alter the T wave, not the ST segment. We translated findings from simulations to canine to patient models of preconditioning to test the hypothesis that the combination of increased [delta (Δ)] T wave amplitude with decreased ST segment elevation characterizes preconditioning. In simulations, decreased APD caused increased T wave amplitude with minimal ST segment elevation. In contrast, decreased action potential amplitude increased ST segment elevation significantly. In a canine model of preconditioning (9 mongrel dogs undergoing 4 ischemia-reperfusion episodes), ST segment amplitude increased more than T wave amplitude during the first ischemic episode [ΔT/ΔST slope = 0.81, 95% confidence interval (CI) 0.46-1.15]; however, during subsequent ischemic episodes the T wave increased significantly more than the ST segment (ΔT/ΔST slope = 2.43, CI 2.07-2.80) (P < 0.001 for interaction of occlusions 2 vs. 1). A similar result was observed in patients (9 patients undergoing 2 consecutive prolonged occlusions during elective percutaneous coronary intervention), with an increase in slope of ΔT/ΔST of 0.13 (CI -0.15 to 0.42) in the first occlusion to 1.02 (CI 0.31-1.73) in the second occlusion (P = 0.02). This integrated analysis of the T wave and ST segment goes beyond the standard approach to only analyze ST elevation, and detects cellular electrophysiology changes of preconditioning.


Assuntos
Algoritmos , Diagnóstico por Computador/métodos , Eletrocardiografia/métodos , Precondicionamento Isquêmico Miocárdico/métodos , Modelos Cardiovasculares , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Traumatismo por Reperfusão Miocárdica/terapia , Animais , Simulação por Computador , Cães , Humanos , Masculino , Traumatismo por Reperfusão Miocárdica/diagnóstico , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resultado do Tratamento
14.
J Electrocardiol ; 47(4): 491-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24952922

RESUMO

The extent and rate at which necrosis develops in experimental acute myocardial infarction in the dog heart is presented together with an analysis of the role played by protective mechanisms in myocyte death. Preconditioning with ischemia delays but does not prevent myocyte death. Arterial collateral flows exceeding 30% of control flow essentially prevent myocyte death, while lesser amounts of collateral flow delay myocyte death to a variable extent. Flows of <0.09mlmin(-1)g(-1) wet exert no protective effect. Cell death occurs as quickly as it does with zero flow. Electrocardiography provides a means of detection of the preconditioned state in the dog heart in that the amount of ST elevation observed during the preconditioning episode is reduced during subsequent episodes of ischemia. Also, marked depression of arterial collateral flow can be detected by an increase in the duration of the QRS segment.


Assuntos
Velocidade do Fluxo Sanguíneo , Circulação Coronária , Precondicionamento Isquêmico/métodos , Modelos Cardiovasculares , Isquemia Miocárdica/prevenção & controle , Isquemia Miocárdica/fisiopatologia , Doença Aguda , Animais , Cães , Isquemia Miocárdica/patologia
15.
Mol Phylogenet Evol ; 69(1): 188-204, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23742885

RESUMO

A molecular phylogeny of Protobranchia, the subclass of bivalve mollusks sister to the remaining Bivalvia, has long proven elusive, because many constituent lineages are deep-sea endemics, which creates methodological challenges for collecting and preserving genetic material. We obtained 74 representatives of all 12 extant protobranch families and investigated the internal phylogeny of this group using sequence data from five molecular loci (16S rRNA, 18S rRNA, 28S rRNA, cytochrome c oxidase subunit I, and histone H3). Model-based and dynamic homology parsimony approaches to phylogenetic reconstruction unanimously supported four major clades of Protobranchia, irrespective of treatment of hypervariable regions in the nuclear ribosomal genes 18S rRNA and 28S rRNA. These four clades correspond to the superfamilies Nuculoidea (excluding Sareptidae), Nuculanoidea (including Sareptidae), Solemyoidea, and Manzanelloidea. Salient aspects of the phylogeny include (1) support for the placement of the family Sareptidae with Nuculanoidea; (2) the non-monophyly of the order Solemyida (Solemyidae+Nucinellidae); (3) and the non-monophyly of most nuculoid and nuculanoid genera and families. In light of this first family-level phylogeny of Protobranchia, we present a revised classification of the group. Estimation of divergence times in concert with analyses of diversification rates demonstrate the signature of the end-Permian mass extinction in the phylogeny of extant protobranchs.


Assuntos
Bivalves/classificação , Complexo IV da Cadeia de Transporte de Elétrons/classificação , Especiação Genética , Histonas/classificação , Filogenia , RNA Ribossômico/classificação , Algoritmos , Animais , Bivalves/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Extinção Biológica , Variação Genética , Histonas/genética , Funções Verossimilhança , Modelos Genéticos , Oceanos e Mares , RNA Ribossômico/genética , Análise de Sequência de DNA
16.
Zootaxa ; 5293(3): 401-434, 2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37518475

RESUMO

Hadal trenches are perceived as a unique deep-sea ecosystem with fundamentally different communities compared to the nearby abyss. So far, however, scarce information exists about how populations are genetically linked within a trench and about mechanisms for species divergence. The present study presents the morphological and molecular-genetic characterization and description of a new nannoniscid species within the genus Austroniscus Vanhöffen, 1914 obtained from abyssal and hadal depths of the Puerto Rico Trench, NW Atlantic. Samples were collected as part of the Vema-TRANSIT expedition onboard RV Sonne in January 2015. Because of the large depth differences between sampling locations (4,552-8,338 m), we expected to find different species within the genus inhabiting abyssal and hadal sites. Initial morphological examination using traditional light microscopy and Confocal Laser Scanning Microscopy was paired with subsequent molecular analysis based on mtDNA (COI and 16S). Contrary to our assumptions, combined morphological and molecular species delimitation analyses (sGMYC, mPTP, ABGD) revealed the presence of only one species spanning the abyssal and hadal seafloor of the Puerto Rico Trench. In addition, comparison with type material could show that this species belongs to a new species, Austroniscus brandtae n. sp., which is described herein. Incongruence between some species delimitation methods suggesting the presence of multiple species is interpreted as strong genetic population structuring within the trench, which is also supported by the analysis of the haplotype networks. The geographic and bathymetric distribution of Austroniscus species is discussed. The species described herein represents the first in the genus Austroniscus from the Atlantic Ocean and the deepest record of the genus to date, and hence significantly expanding previously known limits of its geographic and bathymetric range.


Assuntos
Isópodes , Animais , Isópodes/genética , DNA Mitocondrial/genética , Ecossistema , Porto Rico
17.
Cureus ; 15(5): e38689, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37292554

RESUMO

Introduction Leg length and offset are important considerations in total hip arthroplasty (THA). Navigation systems are capable of providing intra-operative measurements of leg length and offset, and high accuracy has been shown in experimental studies. This study assesses the accuracy of an imageless navigation system with a pinless femoral array (Hip 5.1, BrainLAB, Feldkirchen, Germany) in measuring leg length and offset changes in vivo. Methods A prospective, consecutive series of 37 patients undergoing navigated THA were included in the study. Intra-operative measurements of leg length and offset were recorded using the navigation system. For each patient, pre- and post-operative digital radiographs were scaled and analyzed to provide radiographic measurements for comparison. Results Measurements of leg length change made by the navigation system showed a strong correlation with the size of change measured radiographically (R = 0.71; p<0.0001). The mean difference between the radiographic and navigational measurement was 2.6mm ± 3.0mm (0.0-16.0mm) (mean, SD, range). The navigation system was accurate to within 1mm of the radiographic measurement in 49% of cases, within 2mm in 66% of cases, and within 5mm in 89% of cases. Measurements of offset change by the navigation system also showed a correlation with radiographic measurements, albeit less pronounced (R = 0.35; p=0.035). The mean difference between navigational and radiographic measurements was 5.5mm ± 4.7mm (0.0-16.0mm) (mean, SD, range). The navigation system was accurate within 1mm of the radiographic measurement in 22% of cases, within 2mm in 35% of cases, and within 5mm in 57% of cases. Conclusions This research demonstrates in vivo that an imageless, non-invasive navigation system is a reliable tool for intra-operative leg length (accurate within 2mm) and to a lesser extent offset measurement (accurate within 5mm) when compared to standard practice of plain film radiographs.

18.
Am J Cardiol ; 204: 276-283, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37562193

RESUMO

It is unknown whether gender influences the atherosclerotic plaque characteristics (APCs) of lesions of varying angiographic stenosis severity. This study evaluated the imaging data of 303 symptomatic patients from the derivation arm of the CREDENCE (Computed TomogRaphic Evaluation of Atherosclerotic Determinants of Myocardial IsChEmia) trial, all of whom underwent coronary computed tomographic angiography and clinically indicated nonemergent invasive coronary angiography upon study enrollment. Index tests were interpreted by 2 blinded core laboratories, one of which performed quantitative coronary computed tomographic angiography using an artificial intelligence application to characterize and quantify APCs, including percent atheroma volume (PAV), low-density noncalcified plaque (LD-NCP), noncalcified plaque (NCP), calcified plaque (CP), lesion length, positive arterial remodeling, and high-risk plaque (a combination of LD-NCP and positive remodeling ≥1.10); the other classified lesions as obstructive (≥50% diameter stenosis) or nonobstructive (<50% diameter stenosis) based on quantitative invasive coronary angiography. The relation between APCs and angiographic stenosis was further examined by gender. The mean age of the study cohort was 64.4 ± 10.2 years (29.0% female). In patients with obstructive disease, men had more LD-NCP PAV (0.5 ± 0.4 vs 0.3 ± 0.8, p = 0.03) and women had more CP PAV (11.7 ± 1.6 vs 8.0 ± 0.8, p = 0.04). Obstructive lesions had more NCP PAV compared with their nonobstructive lesions in both genders, however, obstructive lesions in women also demonstrated greater LD-NCP PAV (0.4 ± 0.5 vs 1.0 ± 1.8, p = 0.03), and CP PAV (17.4 ± 16.5 vs 25.9 ± 18.7, p = 0.03) than nonobstructive lesions. Comparing the composition of obstructive lesions by gender, women had more CP PAV (26.3 ± 3.4 vs 15.8 ± 1.5, p = 0.005) whereas men had more NCP PAV (33.0 ± 1.6 vs 26.7 ± 2.5, p = 0.04). Men had more LD-NCP PAV in nonobstructive lesions compared with women (1.2 ± 0.2 vs 0.6 ± 0.2, p = 0.02). In conclusion, there are gender-specific differences in plaque composition based on stenosis severity.


Assuntos
Doença da Artéria Coronariana , Estenose Coronária , Placa Aterosclerótica , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Placa Aterosclerótica/diagnóstico por imagem , Constrição Patológica , Inteligência Artificial , Angiografia Coronária/métodos , Angiografia por Tomografia Computadorizada/métodos , Valor Preditivo dos Testes , Índice de Gravidade de Doença
19.
Diabetes Care ; 46(2): 416-424, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36577120

RESUMO

OBJECTIVE: This study evaluates the relationship between atherosclerotic plaque characteristics (APCs) and angiographic stenosis severity in patients with and without diabetes. Whether APCs differ based on lesion severity and diabetes status is unknown. RESEARCH DESIGN AND METHODS: We retrospectively evaluated 303 subjects from the Computed TomogRaphic Evaluation of Atherosclerotic Determinants of Myocardial IsChEmia (CREDENCE) trial referred for invasive coronary angiography with coronary computed tomographic angiography (CCTA) and classified lesions as obstructive (≥50% stenosed) or nonobstructive using blinded core laboratory analysis of quantitative coronary angiography. CCTA quantified APCs, including plaque volume (PV), calcified plaque (CP), noncalcified plaque (NCP), low-density NCP (LD-NCP), lesion length, positive remodeling (PR), high-risk plaque (HRP), and percentage of atheroma volume (PAV; PV normalized for vessel volume). The relationship between APCs, stenosis severity, and diabetes status was assessed. RESULTS: Among the 303 patients, 95 (31.4%) had diabetes. There were 117 lesions in the cohort with diabetes, 58.1% of which were obstructive. Patients with diabetes had greater plaque burden (P = 0.004). Patients with diabetes and nonobstructive disease had greater PV (P = 0.02), PAV (P = 0.02), NCP (P = 0.03), PAV NCP (P = 0.02), diseased vessels (P = 0.03), and maximum stenosis (P = 0.02) than patients without diabetes with nonobstructive disease. APCs were similar between patients with diabetes with nonobstructive disease and patients without diabetes with obstructive disease. Diabetes status did not affect HRP or PR. Patients with diabetes had similar APCs in obstructive and nonobstructive lesions. CONCLUSIONS: Patients with diabetes and nonobstructive stenosis had an association to similar APCs as patients without diabetes who had obstructive stenosis. Among patients with nonobstructive disease, patients with diabetes had more total PV and NCP.


Assuntos
Aterosclerose , Doença da Artéria Coronariana , Estenose Coronária , Diabetes Mellitus , Placa Aterosclerótica , Humanos , Constrição Patológica/complicações , Estudos Retrospectivos , Doença da Artéria Coronariana/complicações , Placa Aterosclerótica/diagnóstico por imagem , Angiografia Coronária/métodos , Aterosclerose/complicações , Angiografia por Tomografia Computadorizada/métodos , Diabetes Mellitus/epidemiologia , Inteligência Artificial , Estenose Coronária/complicações , Valor Preditivo dos Testes
20.
Biochemistry ; 51(13): 2717-36, 2012 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-22417459

RESUMO

The absorption spectrum of the main antenna complex of photosystem II, LHCII, has been modeled using, as starting points, the chlorophyll (chl) atomic coordinates as obtained by the LHCII crystal analysis [Liu, Z., Yan, H., Wang, K., Kuang, T., Zhang, J., Gui, L., An, X., and Chang, W. (2004) Nature 428, 287-292] of three different trimers. The chl site Q(y) transition energies have been obtained in terms of the chl macrocycle deformations influencing the energy level of the chl frontier orbitals. Using these chl site transition energy values and the entire set of interaction energies, calculated in the ideal dipole approximation, the complete Hamiltonians for the three LHCII trimers have been written and the full set of 42 eigenstates of each LHCII trimer have been calculated. With the 42 transition energies and transition dipole strengths, either unperturbed or associated to the eigenstates, the LHCII Q(y) absorption spectrum has been calculated using a chl absorption band shape. These calculations have been performed both in vacuo and in the presence of a medium. Despite the number of approximations, a good correlation with the measured absorption spectrum of a LHCII preparation is obtained. This analysis shows that, although a substantial C3 symmetry of the LHCII trimer in terms of both chl-chl distances and interaction energies is present, a marked variation among monomer subsets of site transition energies is estimated. This leads to a C3 symmetry breaking in the unperturbed chl site transition energies set and, consequently, in the trimer eigenstates. It is also concluded that interactions among chlorophylls do not significantly modify the light absorption role of LHCII in plant leaves.


Assuntos
Clorofila/metabolismo , Complexos de Proteínas Captadores de Luz/metabolismo , Complexos de Proteínas Captadores de Luz/química , Conformação Proteica
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