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1.
J Assist Reprod Genet ; 41(2): 253-275, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37947940

RESUMO

PURPOSE: Although significant improvements in assisted reproductive technology (ART) outcomes have been accomplished, a critical question remains: which embryo is most likely to result in a pregnancy? Embryo selection is currently based on morphological and genetic criteria; however, these criteria do not fully predict good-quality embryos and additional objective criteria are needed. The cumulus cells are critical for oocyte and embryo development. This systematic review assessed biomarkers in cumulus-oocyte complexes and their association with successful IVF outcomes. METHODS: A comprehensive search was conducted using PubMed, Embase, Scopus, and Web of Science from inception until November 2022. Only English-language publications were included. Inclusion criteria consisted of papers that evaluated genetic biomarkers associated with the cumulus cells (CCs) in humans and the following three outcomes of interest: oocyte quality, embryo quality, and clinical outcomes, including fertilization, implantation, pregnancy, and live birth rates. RESULTS: The search revealed 446 studies of which 42 met eligibility criteria. Nineteen studies correlated genetic and biochemical biomarkers in CCs with oocyte quality. A positive correlation was reported between oocyte quality and increased mRNA expression in CCs of genes encoding for calcium homeostasis (CAMK1D), glucose metabolism (PFKP), extracellular matrix (HAS2, VCAN), TGF-ß family (GDF9, BMP15), and prostaglandin synthesis (PTGS2). Nineteen studies correlated genetic and biochemical biomarkers in CCs with embryo quality. A positive correlation was reported between embryo quality and increased mRNA expression in CCs of genes encoding for extracellular matrix (HAS2), prostaglandin synthesis (PTGS2), steroidogenesis (GREM1), and decreased expression of gene encoding for hormone receptor (AMHR2). Twenty-two studies assessed genetic and biochemical biomarkers in CCs with clinical outcomes. Increased expression of genes encoding for extracellular matrix (VCAN), and TGF-ß family (GDF9, BMP15) were positively correlated with pregnancy rate. CONCLUSION: Genetic biomarkers from cumulus cells were associated with oocyte quality (CAMK1D, PFKP, HAS2, VCAN, GDF-9, BMP-15, PTGS2), embryo quality (GREM1, PTGS2, HAS2), and pregnancy rate (GDF9, BMP15, VCAN). These results might help guide future studies directed at tests of cumulus cells to devise objective criteria to predict IVF outcomes.


Assuntos
Células do Cúmulo , Oócitos , Gravidez , Feminino , Humanos , Células do Cúmulo/metabolismo , Ciclo-Oxigenase 2/genética , Oócitos/metabolismo , Fertilização in vitro , Técnicas de Reprodução Assistida , Marcadores Genéticos/genética , RNA Mensageiro/metabolismo , Fator de Crescimento Transformador beta/genética , Prostaglandinas/metabolismo
2.
F S Rep ; 3(2): 116-123, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35789724

RESUMO

Objective: To evaluate the feasibility of generating a center-specific embryo morphokinetic algorithm by time-lapse microscopy to predict clinical pregnancy rates. Design: A retrospective cohort analysis. Setting: Academic fertility clinic in a tertiary hospital setting. Patients: Patients who underwent in vitro fertilization with embryos that underwent EmbryoScope time-lapse microscopy and subsequent transfer between 2014 and 2018. Interventions: None. Main Outcome Measures: Clinical pregnancy. Results: A supervised, random forest learning algorithm from 367 embryos successfully predicted clinical pregnancy from a training set with overall 65% sensitivity and 74% positive predictive value, with an area under the curve of 0.7 for the test set. Similar results were achieved for live birth outcomes. For the secondary analysis, embryo growth morphokinetics were grouped into five clusters using unsupervised clustering. The clusters that had the fastest morphokinetics (time to blastocyst = 97 hours) had pregnancy rates of 54%, whereas a cluster that had the slowest morphokinetics (time to blastocyst = 122 hours) had a pregnancy rate of 71%, although the differences were not statistically significant (P=.356). Other clusters had pregnancy rates of 51%-60%. Conclusions: This study shows the feasibility of a clinic-specific, noninvasive embryo morphokinetic simple machine learning model to predict clinical pregnancy rates.

3.
Biology (Basel) ; 9(7)2020 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-32708356

RESUMO

Edge-to-edge repair for mitral valve regurgitation is being increasingly performed in high-surgical risk patients using minimally invasive mitral clipping devices. Known procedural complications include chordal rupture and mitral leaflet perforation. Hence, it is important to quantitatively evaluate the effect of edge-to-edge repair on chordal integrity. in this study, we employ a computational mitral valve model to simulate functional mitral regurgitation (FMR) by creating papillary muscle displacement. Edge-to-edge repair is then modeled by simulated coaptation of the mid portion of the mitral leaflets. in the setting of simulated FMR, edge-to-edge repair was shown to sustain low regurgitant orifice area, until a two fold increase in the inter-papillary muscle distance as compared to the normal mitral valve. Strain in the chordae was evaluated near the papillary muscles and the leaflets. Following edge-to-edge repair, strain near the papillary muscles did not significantly change relative to the unrepaired valve, while strain near the leaflets increased significantly relative to the unrepaired valve. These data demonstrate the potential for computational simulations to aid in the pre-procedural evaluation of possible complications such as chordal rupture and leaflet perforation following percutaneous edge-to-edge repair.

4.
J Surg Res ; 243: 399-409, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31277018

RESUMO

BACKGROUND: Extracorporeal membrane oxygenation (ECMO), a rescue therapy for pulmonary failure, has traditionally been limited by anticoagulation requirements. Recent practice has challenged the absolute need for anticoagulation, expanding the role of ECMO to patients with higher bleeding risk. We hypothesize that mortality, bleeding, thrombotic events, and transfusions do not differ between heparin-sparing and full therapeutic anticoagulation strategies in veno-venous (VV) ECMO management. MATERIALS AND METHODS: Adult VV ECMO patients between October 2011 and May 2018 at a single center were reviewed. A heparin-sparing strategy was implemented in October 2014; we compared outcomes in an as-treated fashion. The primary end point was survival. Secondary end points included bleeding, thrombotic complications, and transfusion requirements. RESULTS: Forty VV ECMO patients were included: 17 (147 circuit-days) before and 23 (214 circuit-days) after implementation of a heparin-sparing protocol. Patients treated with heparin-sparing anticoagulation had a lower body mass index (28.5 ± 7.1 versus 38.1 ± 12.4, P = 0.01), more often required inotropic support before ECMO (82 versus 50%, P = 0.05), and had a lower mean activated clotting time (167 ± 15 versus 189 ± 15 s, P < 0.01). There were no significant differences in survival to decannulation (59 versus 83%, P = 0.16) or discharge (50 versus 72%, P = 0.20), bleeding (32 versus 33%, P = 1.0), thromboembolic events (18 versus 39%, P = 0.17), or transfusion requirements (median 1.1 versus 0.9 unit per circuit-day, P = 0.48). CONCLUSIONS: Survival, bleeding, thrombotic complications, and transfusion requirements did not differ between heparin-sparing and full therapeutic heparin strategies for management of VV ECMO. VV ECMO can be a safe option in patients with traditional contraindications to anticoagulation.


Assuntos
Anticoagulantes/efeitos adversos , Oxigenação por Membrana Extracorpórea/estatística & dados numéricos , Hemorragia/induzido quimicamente , Heparina/efeitos adversos , Trombose/prevenção & controle , Adulto , Contraindicações de Medicamentos , Oxigenação por Membrana Extracorpórea/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Trombose/etiologia , Adulto Jovem
5.
J Surg Res ; 242: 157-165, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31078900

RESUMO

BACKGROUND: Limited data exist that compare the predominant cardiac preservation solutions (CPSs). MATERIALS AND METHODS: The United Network for Organ Sharing database was retrospectively reviewed from January 1, 2004 to March 31, 2018, for donor hearts. Of 34,614 potential donors, 21,908 remained after applying the exclusion criteria. The CPS analyzed included saline, the University of Wisconsin (UW), cardioplegia, Celsior, and Custodiol. The primary endpoints were recipient survival and posttransplant rejection. Logistic and Cox models were used to quantify survival endpoints. RESULTS: Saline was used as the CPS in 2549 patients (12%), UW in 10,549 (48%), cardioplegia in 1307 (6%), Celsior in 5081 (23%), and Custodiol in 2422 (11%). Donor age ranged from 15 to 68 y (mean = 32.0 y, median = 30.0 y), and 71% were male. Adjusted survival probabilities of recipients whose donor hearts were procured with saline was 96% 30 d, 90% 1 y, UW: 97% 30 d, 92% 1 y, cardioplegia: 95% 30 d, 87% 1 y, Celsior: 96% 30 d, 90% 1 y, and Custodiol: 97% 30 d, 92% 1 y. When these comparisons were adjusted for donor age, sex, ethnicity, ischemic time, recipient age, sex, ethnicity, creatinine, ventricular assist device (VAD), length of stay, region and days on waiting list, cardioplegia solution was demonstrated to have a higher risk of death (30 d, 1 y, overall) and posttransplant rejection versus UW (odds ratio 1.70, P = 0.001; odds ratio 1.63, P < 0.001; hazard ratio 1.22, P < 0.001; hazard ratio 1.21, P < 0.001, respectively). CONCLUSIONS: Cardioplegia solutions for cardiac preservation are associated with a higher mortality in heart transplant recipients.


Assuntos
Soluções Cardioplégicas/efeitos adversos , Rejeição de Enxerto/epidemiologia , Insuficiência Cardíaca/cirurgia , Soluções para Preservação de Órgãos/efeitos adversos , Preservação de Órgãos/efeitos adversos , Adenosina/efeitos adversos , Adolescente , Adulto , Idoso , Aloenxertos/efeitos dos fármacos , Alopurinol/efeitos adversos , Dissacarídeos/efeitos adversos , Eletrólitos/efeitos adversos , Feminino , Seguimentos , Glucose/efeitos adversos , Glutamatos/efeitos adversos , Glutationa/efeitos adversos , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto/efeitos dos fármacos , Coração/efeitos dos fármacos , Insuficiência Cardíaca/mortalidade , Transplante de Coração/efeitos adversos , Histidina/efeitos adversos , Humanos , Insulina/efeitos adversos , Masculino , Manitol/efeitos adversos , Pessoa de Meia-Idade , Preservação de Órgãos/métodos , Cloreto de Potássio/efeitos adversos , Procaína/efeitos adversos , Rafinose/efeitos adversos , Estudos Retrospectivos , Solução Salina/efeitos adversos , Análise de Sobrevida , Resultado do Tratamento , Adulto Jovem
6.
Chem Mater ; 31(1): 251-259, 2019 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33859455

RESUMO

In this paper, we show that gadolinium-loaded synthetic melanin nanoparticles (Gd(III)-SMNPs) exhibit up to a 40-fold enhanced photoacoustic signal intensity relative to synthetic melanin alone and higher than other metal-chelated SMNPs. This property makes these materials useful as dual labeling agents because Gd(III)-SMNPs also behave as magnetic resonance imaging (MRI) contrast agents. As a proof-of-concept, we used these nanoparticles to label human mesenchymal stem cells. Cellular uptake was confirmed with bright-field optical and transmission electron microscopy. The Gd(III)-SMNP-labeled stem cells continued to express the stem cell surface markers CD73, CD90, and CD105 and proliferate. The labeled stem cells were subsequently injected intramyocardially in mice, and the tissue was observed by photoacoustic and MR imaging. We found that the photoacoustic signal increased as the cell number increased (R 2 = 0.96), indicating that such an approach could be employed to discriminate between stem cell populations with a limit of detection of 2.3 × 104 cells in in vitro tests. This multimodal photoacoustic/MRI approach combines the excellent temporal resolution of photoacoustics with the anatomic resolution of MRI.

7.
Chem Soc Rev ; 47(7): 2374-2400, 2018 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-29451571

RESUMO

Sea spray aerosol particles (SSA), formed through wave breaking at the ocean surface, contribute to natural aerosol particle concentrations in remote regions of Earth's atmosphere, and alter the direct and indirect effects of aerosol particles on Earth's radiation budget. In addition, sea spray aerosol serves as suspended surface area that can catalyze trace gas reactions. It has been shown repeatedly that sea spray aerosol is heavily enriched in organic material compared to the surface ocean. The selective enrichment of organic material complicates the selection of representative molecular mimics of SSA for laboratory or computational studies. In this review, we first provide a short introduction to SSA formation processes and discuss chemical transformations of SSA that occur in polluted coastal regions and remote pristine air. We then focus on existing literature of the chemical composition of nascent SSA generated in controlled laboratory experiments and field investigations. We combine the evidence on the chemical properties of nascent SSA with literature measurements of SSA water uptake to assess SSA molecular composition and liquid water content. Efforts to speciate SSA organic material into molecular classes and specific molecules have led to the identification of saccharides, alkanes, free fatty acids, anionic surfactants, dicarboxylic acids, amino acids, proteinaceous matter, and other large macromolecules. However to date, less than 25% of the organic mass of nascent SSA has been quantified at a molecular level. As discussed here, quantitative measurements of size resolved elemental ratios, combined with determinations of water uptake properties, provides unique insight on the concentration of ions within SSA as a function of particle size, pointing to a controlling role for relative humidity and the hygroscopicity of SSA organic material at small particle diameters.

8.
Acc Chem Res ; 50(3): 599-604, 2017 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-28945390

RESUMO

The oceans, atmosphere, and clouds are all interconnected through the release and deposition of chemical species, which provide critical feedback in controlling the composition of our atmosphere and climate. To better understand the couplings between the ocean and atmosphere, it is critical to improve our understanding of the processes that control sea spray aerosol (SSA) composition and which ones plays the dominate role in regulating atmospheric chemistry and climate.

9.
Artigo em Inglês | MEDLINE | ID: mdl-27342229

RESUMO

Over the years, three-dimensional models of the mitral valve have generally been organized around a simplified anatomy. Leaflets have been typically modeled as membranes, tethered to discrete chordae typically modeled as one-dimensional, non-linear cables. Yet, recent, high-resolution medical images have revealed that there is no clear boundary between the chordae and the leaflets. In fact, the mitral valve has been revealed to be more of a webbed structure whose architecture is continuous with the chordae and their extensions into the leaflets. Such detailed images can serve as the basis of anatomically accurate, subject-specific models, wherein the entire valve is modeled with solid elements that more faithfully represent the chordae, the leaflets, and the transition between the two. These models have the potential to enhance our understanding of mitral valve mechanics and to re-examine the role of the mitral valve chordae, which heretofore have been considered to be 'invisible' to the fluid and to be of secondary importance to the leaflets. However, these new models also require a rethinking of modeling assumptions. In this study, we examine the conventional practice of loading the leaflets only and not the chordae in order to study the structural response of the mitral valve apparatus. Specifically, we demonstrate that fully resolved 3D models of the mitral valve require a fluid-structure interaction analysis to correctly load the valve even in the case of quasi-static mechanics. While a fluid-structure interaction mode is still more computationally expensive than a structural-only model, we also show that advances in GPU computing have made such models tractable. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Simulação por Computador , Imageamento Tridimensional/métodos , Valva Mitral/anatomia & histologia , Valva Mitral/fisiologia , Modelos Anatômicos , Cordas Tendinosas/anatomia & histologia , Cordas Tendinosas/fisiologia , Humanos
10.
Ann Biomed Eng ; 45(3): 619-631, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27624659

RESUMO

The chordal structure is a part of mitral valve geometry that has been commonly neglected or simplified in computational modeling due to its complexity. However, these simplifications cannot be used when investigating the roles of individual chordae tendineae in mitral valve closure. For the first time, advancements in imaging, computational techniques, and hardware technology make it possible to create models of the mitral valve without simplifications to its complex geometry, and to quickly run validated computer simulations that more realistically capture its function. Such simulations can then be used for a detailed analysis of chordae-related diseases. In this work, a comprehensive model of a subject-specific mitral valve with detailed chordal structure is used to analyze the distinct role played by individual chordae in closure of the mitral valve leaflets. Mitral closure was simulated for 51 possible chordal rupture points. Resultant regurgitant orifice area and strain change in the chordae at the papillary muscle tips were then calculated to examine the role of each ruptured chorda in the mitral valve closure. For certain subclassifications of chordae, regurgitant orifice area was found to trend positively with ruptured chordal diameter, and strain changes correlated negatively with regurgitant orifice area. Further advancements in clinical imaging modalities, coupled with the next generation of computational techniques will enable more physiologically realistic simulations.


Assuntos
Hemodinâmica , Valva Mitral , Modelos Cardiovasculares , Animais , Valva Mitral/patologia , Valva Mitral/fisiopatologia , Ruptura Espontânea , Ovinos
11.
Phys Chem Chem Phys ; 18(47): 32345-32357, 2016 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-27854367

RESUMO

Transition metals are known to be enriched in organic-coated marine aerosols, but the impact these cations have on their surface properties is not well understood. Here the effect of Zn2+ enrichment on the surface properties of a dipalmitoylphosphatidylcholine (DPPC) monolayer was investigated and compared to that of the alkaline earth metal Sr2+, an ion not enriched in aerosols. Phase behavior of the DPPC film on concentrated aqueous solutions was probed with surface pressure-area isotherms while domain morphology was monitored with Brewster angle microscopy (BAM). Infrared reflection-absorption spectroscopy (IRRAS) and vibrational sum frequency generation (VSFG) spectroscopy were used to assess the impact of cations on the conformation and orientation of alkyl chains as well as the hydration state of the carbonyl and phosphatidylcholine (PC) moieties. Results of compression isotherms and BAM show that Zn2+ strongly interacts with DPPC molecules, and induces condensation of the monolayer while Sr2+ only weakly interacts with the monolayer in expanded phases. Conformational order and orientation of alkyl chains in the condensed phase are not significantly altered by either cation. IRRAS indicates that Sr2+ has weak interactions with the PC headgroup. Zn2+ ions cause dehydration of carbonyl groups and binds to the phosphate group in a 2 : 1 bridging complex. Findings here suggest that Sr2+ is not enriched in aerosols because it behaves similar to a monovalent ion and only weakly interacts with the monolayer, while enrichment of Zn2+ is due to strong binding to the lipid film.

12.
J Phys Chem A ; 120(30): 6029-38, 2016 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-27400255

RESUMO

Current atmospheric models incorporate the values of vaporization enthalpies, ΔHvap, obtained for neat standards, thus disregarding the matrix effects on volatilization. To test the adequacy of this approximation, this study measured enthalpies of vaporization for five polycyclic aromatic hydrocarbons (PAHs) in the form of neat standards (ΔHvap) as well as adsorbed on the surface of silica, graphite, and graphene particles (ΔHvap(eff)), by using simultaneous thermogravimetry-differential scanning calorimetry (TGA-DSC). Measurement of the corresponding activation energy values, Ea(vap) and Ea vap(eff), by TGA using a derivative method was shown to be the most reliable and practical way to assess ΔHvap and ΔHvap(eff). Enthalpies of adsorption (ΔHads) were then calculated from the differences between Ea(vap) and Ea vap(eff), thus paving a way to modeling the solid-gas phase partitioning in atmospheric particulate matter (PM). The PAH adsorption on silica particle surfaces (representing n-π* interactions) resulted in negative values of ΔHads, indicating significant interactions. For graphite particles, positive ΔHads values were obtained; i.e., PAHs did not interact with the particle surface as strongly as observed for PM. PAHs on the surface of graphene particles evaporated in two stages, with the bulk of the mass loss occurring at temperatures lower than those with the neat standard, just as on graphite. Yet, unlike graphite, a small PAH fraction did not evaporate until higher temperatures compared to case of the neat standards and other particle surfaces (37.4-145.7 K), signifying negative, more PM-relevant values of ΔHads, apparently reflecting π-π* interactions and ranging between -7.6 and +32.6 kJ mol(-1), i.e., even larger than for silica, -3.3 to +8.3 kJ mol(-1). Thus, current atmospheric models may underestimate the partitioning of organic species in the particle phase unless matrix adsorption is taken into account.

13.
J Phys Chem Lett ; 7(9): 1692-6, 2016 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-27093579

RESUMO

Although theories have been developed that describe surface activity of organic molecules at the air-water interface, few studies have tested how surface activity impacts the selective transfer of molecules from solution phase into the aerosol phase during bubble bursting. The selective transfer of a series of organic compounds that differ in their solubility and surface activity from solution into the aerosol phase is quantified experimentally for the first time. Aerosol was produced from solutions containing salts and a series of linear carboxlyates (LCs) and dicarboxylates (LDCs) using a bubble bursting process. Surface activity of these molecules dominated the transport across the interface, with enrichment factors of the more surface-active C4-C8 LCs (55 ± 8) being greater than those of C4-C8 LDCs (5 ± 1). Trends in the estimated surface concentrations of LCs at the liquid-air interface agreed well with their relative concentrations in the aerosol phase. In addition, enrichment of LCs was followed by enrichment of calcium with respect to other inorganic cations and depletion of chloride and sulfate.

14.
Biomech Model Mechanobiol ; 15(6): 1619-1630, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27094182

RESUMO

The diversity of mitral valve (MV) geometries and multitude of surgical options for correction of MV diseases necessitates the use of computational modeling. Numerical simulations of the MV would allow surgeons and engineers to evaluate repairs, devices, procedures, and concepts before performing them and before moving on to more costly testing modalities. Constructing, tuning, and validating these models rely upon extensive in vitro characterization of valve structure, function, and response to change due to diseases. Micro-computed tomography ([Formula: see text]CT) allows for unmatched spatial resolution for soft tissue imaging. However, it is still technically challenging to obtain an accurate geometry of the diastolic MV. We discuss here the development of a novel technique for treating MV specimens with glutaraldehyde fixative in order to minimize geometric distortions in preparation for [Formula: see text]CT scanning. The technique provides a resulting MV geometry which is significantly more detailed in chordal structure, accurate in leaflet shape, and closer to its physiological diastolic geometry. In this paper, computational fluid-structure interaction (FSI) simulations are used to show the importance of more detailed subject-specific MV geometry with 3D chordal structure to simulate a proper closure validated against [Formula: see text]CT images of the closed valve. Two computational models, before and after use of the aforementioned technique, are used to simulate closure of the MV.


Assuntos
Imageamento Tridimensional , Valva Mitral/anatomia & histologia , Modelos Cardiovasculares , Animais , Simulação por Computador , Diástole , Valva Mitral/fisiologia , Ovinos , Estresse Mecânico , Microtomografia por Raio-X
15.
Environ Sci Technol ; 50(5): 2477-86, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26828238

RESUMO

The inclusion of organic compounds in freshly emitted sea spray aerosol (SSA) has been shown to be size-dependent, with an increasing organic fraction in smaller particles. Here we have used electrospray ionization-high resolution mass spectrometry in negative ion mode to identify organic compounds in nascent sea spray collected throughout a 25 day mesocosm experiment. Over 280 organic compounds from ten major homologous series were tentatively identified, including saturated (C8-C24) and unsaturated (C12-C22) fatty acids, fatty acid derivatives (including saturated oxo-fatty acids (C5-C18) and saturated hydroxy-fatty acids (C5-C18), organosulfates (C2-C7, C12-C17) and sulfonates (C16-C22). During the mesocosm, the distributions of molecules within some homologous series responded to variations among the levels of phytoplankton and bacteria in the seawater. The average molecular weight and carbon preference index of saturated fatty acids significantly decreased within fine SSA during the progression of the mesocosm, which was not observed in coarse SSA, sea-surface microlayer or in fresh seawater. This study helps to define the molecular composition of nascent SSA and biological processes in the ocean relate to SSA composition.


Assuntos
Aerossóis/análise , Água do Mar/química , Tensoativos/análise , Aerossóis/química , Cromatografia Líquida de Alta Pressão/métodos , Ácidos Graxos/análise , Fitoplâncton , Água do Mar/microbiologia , Espectrometria de Massas por Ionização por Electrospray/métodos , Tensoativos/química
16.
Ann Biomed Eng ; 44(4): 942-53, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26183963

RESUMO

Numerical models of native heart valves are being used to study valve biomechanics to aid design and development of repair procedures and replacement devices. These models have evolved from simple two-dimensional approximations to complex three-dimensional, fully coupled fluid-structure interaction (FSI) systems. Such simulations are useful for predicting the mechanical and hemodynamic loading on implanted valve devices. A current challenge for improving the accuracy of these predictions is choosing and implementing modeling boundary conditions. In order to address this challenge, we are utilizing an advanced in vitro system to validate FSI conditions for the mitral valve system. Explanted ovine mitral valves were mounted in an in vitro setup, and structural data for the mitral valve was acquired with [Formula: see text]CT. Experimental data from the in vitro ovine mitral valve system were used to validate the computational model. As the valve closes, the hemodynamic data, high speed leaflet dynamics, and force vectors from the in vitro system were compared to the results of the FSI simulation computational model. The total force of 2.6 N per papillary muscle is matched by the computational model. In vitro and in vivo force measurements enable validating and adjusting material parameters to improve the accuracy of computational models. The simulations can then be used to answer questions that are otherwise not possible to investigate experimentally. This work is important to maximize the validity of computational models of not just the mitral valve, but any biomechanical aspect using computational simulation in designing medical devices.


Assuntos
Valva Mitral/fisiologia , Modelos Cardiovasculares , Músculos Papilares/fisiologia , Animais , Cordas Tendinosas/diagnóstico por imagem , Cordas Tendinosas/fisiologia , Técnicas In Vitro , Valva Mitral/diagnóstico por imagem , Músculos Papilares/diagnóstico por imagem , Ovinos , Microtomografia por Raio-X
17.
Artigo em Inglês | MEDLINE | ID: mdl-24345236

RESUMO

Exposure to combustion emissions, including diesel engine exhaust and wood smoke particles (DEPs and WSPs), has been associated with inflammatory responses. To investigate the possible role of polycyclic aromatic hydrocarbons (PAHs) and PAH-derivatives, the DEPs and WSPs methanol extracts were fractionated by solid phase extraction (SPE), and the fractions were analyzed for more than ∼120 compounds. The pro-inflammatory effects of the fractionated extracts were characterized by exposure of bronchial epithelial lung cells (BEAS-2B). Both native DEPs and WSPs caused a concentration-dependent increase in IL-6 and IL-8 release and cytotoxicity. This is consistent with the finding of a rather similar total content of PAHs and PAH-derivatives. Yet, the samples differed in specific components, suggesting that different species contribute to the toxicological response in these two types of particles. The majority of the IL-6 release and cytotoxicity was induced upon exposure to the most polar (methanol) SPE fraction of extracts from both samples. In these fractions hydroxy-PAHs, carboxy-PAHs were observed along with nitro-amino-PAHs in DEP. However, the biological effects induced by the polar fractions could not be attributed only to the occurrence of PAH-derivatives. The present findings indicate a need for further characterization of organic extracts, beyond an extensive analysis of commonly suspected PAH and PAH-derivatives. Supplemental materials are available for this article. Go to the publisher's online edition of Journal of Environmental Science and Health, Part A, to view the supplemental file.


Assuntos
Inflamação/induzido quimicamente , Material Particulado/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Emissões de Veículos/toxicidade , Brônquios/citologia , Carbono/análise , Linhagem Celular , Fracionamento Químico , Relação Dose-Resposta a Droga , Células Epiteliais/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Inflamação/metabolismo , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Material Particulado/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/análise , Fumaça/efeitos adversos , Extração em Fase Sólida , Testes de Toxicidade/métodos , Emissões de Veículos/análise , Madeira
18.
Toxicol Lett ; 208(3): 262-8, 2012 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-22100492

RESUMO

Exposure to diesel engine exhaust particles (DEPs), representing a complex and variable mixture of components, has been associated with lung disease and induction of pro-inflammatory mediators and CYP1A1 expression. The aim of this study was to further characterise DEP-components accounting for these effects. Human bronchial epithelial cells (BEAS-2B) were exposed to either native DEPs, or corresponding methanol DEP-extract or residual DEPs, and investigated with respect to cytotoxicity and expression and release of multiple inflammation-related mediators. Both native DEPs and DEP-extract, but not residual DEPs, induced marked mRNA expression of COX-2, IL-6 and IL-8, as well as cytotoxicity and release of IL-6. However, CYP1A1 was primarily induced by the native and residual DEPs. Overall, the results of near-edge X-ray absorption fine structure (NEXAFS) spectroscopy and gas chromatography with mass spectrometry (GC/MS) analysis of DEP-extracts indicated that the majority of the analysed PAHs and PAH-derivatives were extracted from the particles, but that certain PAH-derivatives, probably their carboxylic isomers, tended to be retained on the residual DEPs. Moreover, it appeared that certain components of the methanol extract may suppress CYP1A1 expression. These results provide insight into how different components of the complex DEP-mixture may be differently involved in DEP-induced pro-inflammatory responses and underscore the importance of identifying and clarifying the roles of active DEP-components in relation to different biological effects.


Assuntos
Brônquios/efeitos dos fármacos , Emissões de Veículos/toxicidade , Poluentes Atmosféricos/toxicidade , Brônquios/citologia , Brônquios/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Ciclo-Oxigenase 2/biossíntese , Ciclo-Oxigenase 2/genética , Citocromo P-450 CYP1A1/biossíntese , Citocromo P-450 CYP1A1/genética , Células Epiteliais/efeitos dos fármacos , Humanos , Interleucina-6/biossíntese , Interleucina-6/genética , Interleucina-8/biossíntese , Interleucina-8/genética , Pneumopatias/induzido quimicamente , Pneumopatias/enzimologia , Pneumopatias/patologia , Hidrocarbonetos Policíclicos Aromáticos/química , RNA Mensageiro/química , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Espectroscopia por Absorção de Raios X
19.
Int J Numer Methods Eng ; 26(3-4): 348-380, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20454531

RESUMO

The remodeling that occurs after a posterolateral myocardial infarction can alter mitral valve function by creating conformational abnormalities in the mitral annulus and in the posteromedial papillary muscle, leading to mitral regurgitation (MR). It is generally assumed that this remodeling is caused by a volume load and is mediated by an increase in diastolic wall stress. Thus, mitral regurgitation can be both the cause and effect of an abnormal cardiac stress environment. Computational modeling of ischemic MR and its surgical correction is attractive because it enables an examination of whether a given intervention addresses the correction of regurgitation (fluid-flow) at the cost of abnormal tissue stress. This is significant because the negative effects of an increased wall stress due to the intervention will only be evident over time. However, a meaningful fluid-structure interaction model of the left heart is not trivial; it requires a careful characterization of the in-vivo cardiac geometry, tissue parameterization though inverse analysis, a robust coupled solver that handles collapsing Lagrangian interfaces, automatic grid-generation algorithms that are capable of accurately discretizing the cardiac geometry, innovations in image analysis, competent and efficient constitutive models and an understanding of the spatial organization of tissue microstructure. In this manuscript, we profile our work toward a comprehensive fluid-structure interaction model of the left heart by reviewing our early work, presenting our current work and laying out our future work in four broad categories: data collection, geometry, fluid-structure interaction and validation.

20.
Cancer Cytopathol ; 118(2): 97-104, 2010 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-20225199

RESUMO

BACKGROUND: Endometrial cancer is the most common pelvic gynecological malignancy. The diagnosis of well-differentiated endometrial adenocarcinoma, atypical hyperplasia, and hyperplasia is often challenging. The authors sought to investigate the utility of chromosomal anomalies for the detection of endometrial hyperplasia and carcinoma using multitarget fluorescence in situ hybridization (FISH). METHODS: Samples were collected by endometrial Tao brush and processed by liquid-based cytological preparation protocol from consecutive cases to include 50 benign, 50 hyperplasia without atypia, 47 atypical hyperplasia, and 53 endometrial cancers. Each was hybridized using fluorescence-labeled DNA probes to chromosomes 1, 8, and 10. The FISH signals were enumerated in 100 cells per case, and the chromosomal anomalies were correlated with pathologic findings, including histologic diagnoses on matched endometrial tissue samples. RESULTS: Numeric chromosomal anomalies were found in 0% (0 of 50) of benign, 20% (10 of 50) of hyperplasia, 74% (35 of 47) of atypical hyperplasia, and 87% (46 of 53) of carcinoma specimens. The mean percentage of cells with chromosomal changes was 55% in cancer specimens, which was significantly higher than that in hyperplasia without atypia (13%, P < .0001) and atypical hyperplasia (32%, P = .003). The most frequent chromosomal anomaly was gain of chromosome 1. FISH anomalies had an overall sensitivity of 81% and specificity of 90% for the detection of atypical hyperplasia and/or endometrial carcinoma. There was no association with grade of endometrial carcinoma. CONCLUSIONS: Multitarget FISH appears to be useful for the differential diagnosis of hyperplasia, atypical hyperplasia, and endometrial adenocarcinoma, with a high level of sensitivity and specificity. It is also a potential tool for the early detection of neoplastic cells in endometrial cytology specimens. Endometrial hyperplasia with FISH-detected chromosomal anomalies may represent a clinically significant subset of cases that warrant close clinical follow-up.


Assuntos
Adenocarcinoma/genética , Aberrações Cromossômicas , Hiperplasia Endometrial/genética , Neoplasias do Endométrio/genética , Hibridização in Situ Fluorescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Cromossomos Humanos Par 1 , Cromossomos Humanos Par 10 , Cromossomos Humanos Par 8 , Hiperplasia Endometrial/diagnóstico , Neoplasias do Endométrio/diagnóstico , Feminino , Humanos , Pessoa de Meia-Idade , Sensibilidade e Especificidade
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