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Organ-Chips Enhance the Maturation of Human iPSC-Derived Dopamine Neurons. Int J Mol Sci 2023; 24:14227. [PMID: 37762529 PMCID: PMC10531789 DOI: 10.3390/ijms241814227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 09/06/2023] [Accepted: 09/08/2023] [Indexed: 09/29/2023] Open
Abstract
While cells in the human body function in an environment where the blood supply constantly delivers nutrients and removes waste, cells in conventional tissue culture well platforms are grown with a static pool of media above them and often lack maturity, limiting their utility to study cell biology in health and disease. In contrast, organ-chip microfluidic systems allow the growth of cells under constant flow, more akin to the in vivo situation. Here, we differentiated human induced pluripotent stem cells into dopamine neurons and assessed cellular properties in conventional multi-well cultures and organ-chips. We show that organ-chip cultures, compared to multi-well cultures, provide an overall greater proportion and homogeneity of dopaminergic neurons as well as increased levels of maturation markers. These organ-chips are an ideal platform to study mature dopamine neurons to better understand their biology in health and ultimately in neurological disorders.
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Integrating EM and Patch-seq data: Synaptic connectivity and target specificity of predicted Sst transcriptomic types. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.22.533857. [PMID: 36993629 PMCID: PMC10055412 DOI: 10.1101/2023.03.22.533857] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Neural circuit function is shaped both by the cell types that comprise the circuit and the connections between those cell types 1 . Neural cell types have previously been defined by morphology 2, 3 , electrophysiology 4, 5 , transcriptomic expression 6-8 , connectivity 9-13 , or even a combination of such modalities 14-16 . More recently, the Patch-seq technique has enabled the characterization of morphology (M), electrophysiology (E), and transcriptomic (T) properties from individual cells 17-20 . Using this technique, these properties were integrated to define 28, inhibitory multimodal, MET-types in mouse primary visual cortex 21 . It is unknown how these MET-types connect within the broader cortical circuitry however. Here we show that we can predict the MET-type identity of inhibitory cells within a large-scale electron microscopy (EM) dataset and these MET-types have distinct ultrastructural features and synapse connectivity patterns. We found that EM Martinotti cells, a well defined morphological cell type 22, 23 known to be Somatostatin positive (Sst+) 24, 25 , were successfully predicted to belong to Sst+ MET-types. Each identified MET-type had distinct axon myelination patterns and synapsed onto specific excitatory targets. Our results demonstrate that morphological features can be used to link cell type identities across imaging modalities, which enables further comparison of connectivity in relation to transcriptomic or electrophysiological properties. Furthermore, our results show that MET-types have distinct connectivity patterns, supporting the use of MET-types and connectivity to meaningfully define cell types.
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Interpopulation characterization of quinoa (Chenopodium quinoa Willd.) from different agroecological environments of Colombia. BRAZ J BIOL 2023; 83:e271954. [PMID: 37132743 DOI: 10.1590/1519-6984.271954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Accepted: 03/24/2023] [Indexed: 05/04/2023] Open
Abstract
Chenopodium quinoa Willd. it is an Andean cereal of great importance for human consumption due to its high nutritional value. In Colombia there is a high phenotypic and genotypic variability within quinoa crops, which has not been studied and has been maintained by the same farmers cycle after production cycle. The objective of this study was to carry out an interpopulation characterization of quinoa cultivated in different producing municipalities of the department of Boyacá, in Colombia, for which 19 morphological descriptors were used, which were evaluated in situ in nine municipalities and analyzed through descriptive statistics, principal component analysis, correlation and conglomerates. In the evaluation of the quantitative traits for all the populations, it was observed that the most variable descriptors were Number of teeth lower leaf (DHI), Lower leaf length (LHI), Width upper leaf (AHI) and Number of teeth upper leaf (DHS). Great segregation between and within individuals of Blanca de Jericó and Piartal was observed for panicle and leaf color and shape, stem color, presence of teeth, and axils on upper and lower leaves. A classification key is proposed that allows in the field to be able to morphologically differentiate the genotypes of Piartal and Blanca de Jericó. This research shows that among the most cultivated genotypes in the department of Boyacá, there is still an important phenotypic diversity given at the inter and intra-individual level, due to the phenological state and the agroclimatological conditions of the different producing regions.
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Predictors of long term tricuspid regurgitation after pulmonary valve replacement: a single center study on the cohort of significant preoperative tricuspid regurgitation. Eur Heart J 2022. [DOI: 10.1093/eurheartj/ehac544.1845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
Almost one-third of repaired tetralogy of Fallot (TOF) and pulmonary stenosis (PS) patients referred for pulmonary valve replacement (PVR) have at least moderate tricuspid regurgitation (TR). Predictors of long term TR in this population are not well defined and the role of Tricuspid Annuloplasty (TA) in addition to PVR in this setting is controversial.
Purpose
Patients with preoperative severe TR or moderate TR with dilated tricuspid annulus (>40mm) undergo TA at the time of PVR as per protocol in our instititution. The aim of this observational study was to evaluate the long term results of this approach and to identify predictors of significant TR at the end of follow-up.
Material and methods
We retrospectively reviewed 35 repaired TOF and PS patients who underwent surgical PVR with (n=17, group 1) or without (n=18, group 2) TA in a single tertiary hospital between June-2009 and June-2021. Pre- and postoperative echocardiographic and cardiac magnetic resonance data were assessed for TR severity and right ventricle size and systolic function. Baseline and clinical follow up data were collected. Uni- and multivariable tests were used to analyze predictors of at least moderate TR after PVR.
Results
Mean age at PVR and baseline image parameters were comparable between groups, except for TR grade (p 0.006), tricuspid annulus size (p 0.018) and right ventricle outflow tract diameter (p 0.04) which were greater in group 1. TA did not confer and increased risk of surgical and peroperative complications. Intensive care unit (p 0.94) and total hospital admission days (p 0.59) did not differ among groups. At one year, TR grade significantly improved regardless of TA. At the end of follow-up (5.29±2.9 years), the degree of TR increased in both groups with no differences between groups (p 0.38) (see table 1). In univariable analysis, two independent predictors of at least moderate TR at end of follow-up were identified; mixed TR mechanism (OR 12.5, p 0.006) and severe preoperative TR grade (OR 10.21, p 0.003). Mixed TR mechanism (OR 15.78, p 0.01) and a right ventricle ejection fraction below 45% (OR 1.47, p 0.01) were identified as risk factors of significant TR in multivariable analysis (see Table 2).
Conclusions
TA seems a reasonable approach at the time of PVR in patients with severe TR or moderate TR with dilated annulus. Mixed TR mechanism and a worse right ventricular function have been identified as independent predictors factors of long term significant postoperative TR in our study cohort.
Funding Acknowledgement
Type of funding sources: None.
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Mutual synchronization of spin-torque oscillators within a ring array. Sci Rep 2022; 12:12030. [PMID: 35835771 PMCID: PMC9283394 DOI: 10.1038/s41598-022-15483-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Accepted: 05/12/2022] [Indexed: 11/09/2022] Open
Abstract
An array of spin torque nano-oscillators (STNOs), coupled by dipolar interaction and arranged on a ring, has been studied numerically and analytically. The phase patterns and locking ranges are extracted as a function of the number N, their separation, and the current density mismatch between selected subgroups of STNOs. If \documentclass[12pt]{minimal}
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\begin{document}$$N\ge 6$$\end{document}N≥6 for identical current densities through all STNOs, two degenerated modes are identified an in-phase mode (all STNOs have the same phase) and a splay mode (the phase makes a 2\documentclass[12pt]{minimal}
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\begin{document}$$\pi$$\end{document}π turn along the ring). When inducing a current density mismatch between two subgroups, additional phase shifts occur. The locking range (maximum current density mismatch) of the in-phase mode is larger than the one for the splay mode and depends on the number N of STNOs on the ring as well as on the separation. These results can be used for the development of magnetic devices that are based on STNO arrays.
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Magnetostatic interaction between two bubble skyrmions. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2020; 32:175801. [PMID: 31931481 DOI: 10.1088/1361-648x/ab6aec] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
A detailed analytic and numerical analysis of the interaction between two bubble skyrmions has been carried out. The results from the micromagnetic calculations show that when the skyrmions are in the same plane, the magnetic parameters vary weakly as a function of the separation between them. On the other hand, when the skyrmions are located in the same vertical axis, the magnetic parameters show a strong variation as a function of the separation of the skyrmions. In particular, when a magnetic disk is over another, there is a transition from a Bloch-like skyrmion configuration to a Néel-like skyrmion configuration as the distance between the disks decreases, as a consequence of the magnetostatic interaction. Therefore, it is possible to stabilize a bubble skyrmion with a Néel configuration without the Dzyaloshinskii-Moriya interaction. Thus, these results can be used for the control of the skyrmion parameters in magnetic spintronic devices that need to use these configurations.
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Ascorbic acid increases SVCT2 localization at the plasma membrane by accelerating its trafficking from early secretory compartments and through the endocytic-recycling pathway. Free Radic Biol Med 2018; 120:181-191. [PMID: 29545069 DOI: 10.1016/j.freeradbiomed.2018.03.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 03/06/2018] [Accepted: 03/08/2018] [Indexed: 11/30/2022]
Abstract
Ascorbic acid (Asc) is an antioxidant molecule essential for physiological functions. The concentration of extracellular Asc increases during synaptic transmission and renal reabsorption. These phenomena induce an increase of the Sodium-dependent-Vitamin-C-transporter 2 (SVCT2) at plasma membrane (PM) localization, as we previously demonstrated in neuronal and non-neuronal cells. Hence, the aim of this study was to evaluate intracellular SVCT2 trafficking kinetics in response to Asc. We observed two peaks of SVCT2 localization and function at the PM (at 5-10 min, "acute response", and 30-60 min, "post-acute response") when cells were incubated with Asc. We defined that the post-acute response was dependent on SVCT2 located in early secretory compartments, and its trafficking was abolished with Tunicamycin and Brefeldin A treatment. Moreover, using the RUSH system to retain and synchronize cargo secretion through the secretory pathway we demonstrated that the post-acute response increases SVCT2 trafficking kinetics from the ER to the PM suggesting the retention of SVCT2 at the early secretory pathway when Asc is absent. However, these observations do not explain the increased SVCT2 levels at the PM during the "acute" response, suggesting the involvement of a faster mechanism in close proximity with the PM. To investigate the possible role of endosomal compartments, we tested the effect of endocytosis inhibition. Expression of dominant-negative (DN) versions of the GTPase-dynamin II and clathrin-accessory protein AP180 showed a significant increase in SVCT2 levels at the PM. Moreover, expression of Rab11-DN, a GTPase implicated in cargo protein recycling from endosomes to the PM showed a similar outcome, strongly indicating that Asc impacts SVCT2 trafficking during the acute response. Therefore, our results revealed two mechanisms by which Asc modulates SVCT2 levels at the PM, one at the early secretory pathway and another at the endocytic compartments. We propose that these two mechanisms have key protective implications in the homeostasis of metabolically active and specialized tissues.
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A pragmatic approach for mortality prediction after surgery in infective endocarditis: optimizing and refining EuroSCORE. Clin Microbiol Infect 2018; 24:1102.e7-1102.e15. [PMID: 29408350 DOI: 10.1016/j.cmi.2018.01.019] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Revised: 01/13/2018] [Accepted: 01/20/2018] [Indexed: 01/13/2023]
Abstract
OBJECTIVE To simplify and optimize the ability of EuroSCORE I and II to predict early mortality after surgery for infective endocarditis (IE). METHODS Multicentre retrospective study (n = 775). Simplified scores, eliminating irrelevant variables, and new specific scores, adding specific IE variables, were created. The performance of the original, recalibrated and specific EuroSCOREs was assessed by Brier score, C-statistic and calibration plot in bootstrap samples. The Net Reclassification Index was quantified. RESULTS Recalibrated scores including age, previous cardiac surgery, critical preoperative state, New York Heart Association >I, and emergent surgery (EuroSCORE I and II); renal failure and pulmonary hypertension (EuroSCORE I); and urgent surgery (EuroSCORE II) performed better than the original EuroSCOREs (Brier original and recalibrated: EuroSCORE I: 0.1770 and 0.1667; EuroSCORE II: 0.2307 and 0.1680). Performance improved with the addition of fistula, staphylococci and mitral location (EuroSCORE I and II) (Brier specific: EuroSCORE I 0.1587, EuroSCORE II 0.1592). Discrimination improved in specific models (C-statistic original, recalibrated and specific: EuroSCORE I: 0.7340, 0.7471 and 0.7728; EuroSCORE II: 0.7442, 0.7423 and 0.7700). Calibration improved in both EuroSCORE I models (intercept 0.295, slope 0.829 (original); intercept -0.094, slope 0.888 (recalibrated); intercept -0.059, slope 0.925 (specific)) but only in specific EuroSCORE II model (intercept 2.554, slope 1.114 (original); intercept -0.260, slope 0.703 (recalibrated); intercept -0.053, slope 0.930 (specific)). Net Reclassification Index was 5.1% and 20.3% for the specific EuroSCORE I and II. CONCLUSIONS The use of simplified EuroSCORE I and EuroSCORE II models in IE with the addition of specific variables may lead to simpler and more accurate models.
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Poster session 1Cell growth, differentiation and stem cells - Heart72Understanding the metabolism of cardiac progenitor cells: a first step towards controlling their proliferation and differentiation?73Expression of pw1/peg3 identifies a new cardiac adult stem cell population involved in post-myocardial infarction remodeling74Long-term stimulation of iPS-derived cardiomyocytes using optogenetic techniques to promote phenotypic changes in E-C coupling75Benefits of electrical stimulation on differentiation and maturation of cardiomyocytes from human induced pluripotent stem cells76Constitutive beta-adrenoceptor-mediated cAMP production controls spontaneous automaticity of human induced pluripotent stem cell-derived cardiomyocytes77Formation and stability of T-tubules in cardiomyocytes78Identification of miRNAs promoting human cardiomyocyte proliferation by regulating Hippo pathway79A direct comparison of foetal to adult epicardial cell activation reveals distinct differences relevant for the post-injury response80Role of neuropilins in zebrafish heart regeneration81Highly efficient immunomagnetic purification of cardiomyocytes derived from human pluripotent stem cells82Cardiac progenitor cells posses a molecular circadian clock and display large 24-hour oscillations in proliferation and stress tolerance83Influence of sirolimus and everolimus on bone marrow-derived mesenchymal stem cell biology84Endoglin is important for epicardial behaviour following cardiac injuryCell death and apoptosis - Heart87Ultrastructural alterations reflecting Ca2+ handling and cell-to-cell coupling disorders precede occurrence of severe arrhythmias in intact animal heart88Urocortin-1 promotes cardioprotection through ERK1/2 and EPAC pathways: role in apoptosis and necrosis89Expression p38 MAPK and Cas-3 in myocardium LV of rats with experimental heart failure at melatonin and enalapril introductionTranscriptional control and RNA species - Heart92Accumulation of beta-amyloid 1-40 in HF patients: the role of lncRNA BACE1-AS93Role of miR-182 in zebrafish and mouse models of Holt-Oram syndrome94Mir-27 distinctly regulates muscle-enriched transcription factors and growth factors in cardiac and skeletal muscle cells95AF risk factors impair PITX2 expression leading to Wnt-microRNA-ion channel remodelingCytokines and cellular inflammation - Heart98Post-infarct survival depends on the interplay of monocytes, neutrophils and interferon gamma in a mouse model of myocardial Infarction99Inflammatory cd11b/c cells play a protective role in compensated cardiac hypertrophy by promoting an orai3-related pro-survival signal100Anti-inflammatory effects of endothelin receptor blockade in the atrial tissue of spontaneously hypertensive rats101Mesenchymal stromal cells reduce NLRP3 inflammasome activity in Coxsackievirus B3-induced myocarditis102Mesenchymal stromal cells modulate monocytes trafficking in Coxsackievirus B3-induced myocarditis103The impact of regulatory T lymphocytes on long-term mortality in patients with chronic heart failure104Temporal dynamics of dendritic cells after ST-elevation myocardial infarction relate with improvement of myocardial functionGrowth factors and neurohormones - Heart107Preconditioning of hypertrophied heart: miR-1 and IGF-1 crosstalk108Modulation of catecholamine secretion from human adrenal chromaffin cells by manipulation of G protein-coupled receptor kinase-2 activity109Evaluation of cyclic adenosin-3,5- monophosphate and neurohormones in patients with chronic heart failureNitric oxide and reactive oxygen species - Heart112Hydrogen sulfide donor inhibits oxidative and nitrosative stress, cardiohemodynamics disturbances and restores cNOS coupling in old rats113Role and mechanisms of action of aldehydes produced by monoamine oxidase A in cardiomyocyte death and heart failure114Exercise training has contrasting effects in myocardial infarction and pressure-overload due to different endothelial nitric oxide synthase regulation115S-Nitroso Human Serum Albumin dose-dependently leads to vasodilation and alters reactive hyperaemia in coronary arteries of an isolated mouse heart model116Modulating endothelial nitric oxide synthase with folic acid attenuates doxorubicin-induced cardiomyopathy119Effects of long-term very high intensity exercise on aortic structure and function in an animal model120Electron paramagnetic resonance spectroscopy quantification of nitrosylated hemoglobin (HbNO) as an index of vascular nitric oxide bioavailability in vivo121Deletion of repressor activator protein 1 impairs acetylcholine-induced relaxation due to production of reactive oxygen speciesExtracellular matrix and fibrosis - Heart124MicroRNA-19b is associated with myocardial collagen cross-linking in patients with severe aortic stenosis. Potential usefulness as a circulating biomarker125A new ex vivo model to study cardiac fibrosis126Heterogeneity of fibrosis and fibroblast differentiation in the left ventricle after myocardial infarction127Effect of carbohydrate metabolism degree compensation to the level of galectin-3 changes in hypertensive patients with chronic heart failure and type 2 diabetes mellitus128Statin paradox in association with calcification of bicuspid aortic valve interstitial cells129Cardiac function remains impaired despite reversible cardiac fibrosis after healed experimental viral myocarditisIon channels, ion exchangers and cellular electrophysiology - Heart132Identifying a novel role for PMCA1 (Atp2b1) in heart rhythm instability133Mutations of the caveolin-3 gene as a predisposing factor for cardiac arrhythmias134The human sinoatrial node action potential: time for a computational model135iPSC-derived cardiomyocytes as a model to dissect ion current alterations of genetic atrial fibrillation136Postextrasystolic potentiation in healthy and diseased hearts: effects of the site of origin and coupling interval of the preceding extrasystole137Absence of Nav1.8-based (late) sodium current in rabbit cardiomyocytes and human iPSC-CMs138hiPSC-derived cardiomyocytes from Brugada Syndrome patients without identified mutations do not exhibit cellular electrophysiological abnormalitiesMicrocirculation141Atherogenic indices, collagen type IV turnover and the development of microvascular complications- study in diabetics with arterial hypertension142Changes in the microvasculature and blood viscosity in women with rheumatoid arthritis, hypercholesterolemia and hypertensionAtherosclerosis145Shear stress regulates endothelial autophagy: consequences on endothelial senescence and atherogenesis146Obstructive sleep apnea causes aortic remodeling in a chronic murine model147Aortic perivascular adipose tissue displays an aged phenotype in early and late atherosclerosis in ApoE-/- mice148A systematic evaluation of the cellular innate immune response during the process of human atherosclerosis149Inhibition of Coagulation factor Xa increases plaque stability and attenuates the onset and progression of atherosclerotic plaque in apolipoprotein e-deficient mice150Regulatory CD4+ T cells from patients with atherosclerosis display pro-inflammatory skewing and enhanced suppression function151Hypoxia-inducible factor (HIF)-1alpha regulates macrophage energy metabolism by mediating miRNAs152Extracellular S100A4 is a key player of smooth muscle cell phenotypic transition: implications in atherosclerosis153Microparticles of healthy origins improve atherosclerosis-associated endothelial progenitor cell dysfunction via microRNA transfer154Arterial remodeling and metabolism impairment in early atherosclerosis155Role of pannexin1 in atherosclerotic plaque formationCalcium fluxes and excitation-contraction coupling158Amphiphysin II induces tubule formation in cardiac cells159Interleukin 1 beta regulation of connexin 43 in cardiac fibroblasts and the effects of adult cardiac myocyte:fibroblast co-culture on myocyte contraction160T-tubular electrical defects contribute to blunted beta-adrenergic response in heart failure161Beat-to-beat variability of intracellular Ca2+ dynamics of Purkinje cells in the infarct border zone of the mouse heart revealed by rapid-scanning confocal microscopy162The efficacy of late sodium current blockers in hypertrophic cardiomyopathy is dependent on genotype: a study on transgenic mouse models with different mutations163Synthesis of cADPR and NAADP by intracellular CD38 in heart: role in inotropic and arrhythmogenic effects of beta-adrenoceptor signalingContractile apparatus166Towards an engineered heart tissue model of HCM using hiPSC expressing the ACTC E99K mutation167Diastolic mechanical load delays structural and functional deterioration of ultrathin adult heart slices in culture168Structural investigation of the cardiac troponin complex by molecular dynamics169Exercise training restores myocardial and oxidative skeletal muscle function from myocardial infarction heart failure ratsOxygen sensing, ischaemia and reperfusion172A novel antibody specific to full-length stromal derived factor-1 alpha reveals that remote conditioning induces its cleavage by endothelial dipeptidyl peptidase 4173Attenuation of myocardial and vascular arginase activity by vagal nerve stimulation via a mechanism involving alpha-7 nicotinic receptor during cardiac ischemia and reperfusion174Novel nanoparticle-mediated medicine for myocardial ischemia-reperfusion injury simultaneously targeting mitochondrial injury and myocardial inflammation175Acetylcholine plays a key role in myocardial ischaemic preconditioning via recruitment of intrinsic cardiac ganglia176The role of nitric oxide and VEGFR-2 signaling in post ischemic revascularization and muscle recovery in aged hypercholesterolemic mice177Efficacy of ischemic preconditioning to protect the human myocardium: the role of clinical conditions and treatmentsCardiomyopathies and fibrosis180Plakophilin-2 haploinsufficiency leads to impaired canonical Wnt signaling in ARVC patient181Improved technique for customized, easier, safer and more reliable transverse aortic arch banding and debanding in mice as a model of pressure overload hypertrophy182Late sodium current inhibitors for the treatment of inducible obstruction and diastolic dysfunction in hypertrophic cardiomyopathy: a study on human myocardium183Angiotensin II receptor antagonist fimasartan has protective role of left ventricular fibrosis and remodeling in the rat ischemic heart184Role of High-Mobility Group Box 1 (HMGB1) redox state on cardiac fibroblasts activities and heart function after myocardial infarction185Atrial remodeling in hypertrophic cardiomyopathy: insights from mouse models carrying different mutations in cTnT186Electrophysiological abnormalities in ventricular cardiomyocytes from a Maine Coon cat with hypertrophic cardiomyopathy: effects of ranolazine187ZBTB17 is a novel cardiomyopathy candidate gene and regulates autophagy in the heart188Inhibition of SRSF4 in cardiomyocytes induces left ventricular hypertrophy189Molecular characterization of a novel cardiomyopathy related desmin frame shift mutation190Autonomic characterisation of electro-mechanical remodeling in an in-vitro leporine model of heart failure191Modulation of Ca2+-regulatory function by three novel mutations in TNNI3 associated with severe infant restrictive cardiomyopathyAging194The aging impact on cardiac mesenchymal like stromal cells (S+P+)195Reversal of premature aging markers after bariatric surgery196Sex-associated differences in vascular remodeling during aging: role of renin-angiotensin system197Role of the receptor for advanced glycation end-products (RAGE) in age dependent left ventricle dysfunctionsGenetics and epigenetics200hsa-miR-21-5p as a key factor in aortic remodeling during aneurysm formation201Co-inheritance of mutations associated with arrhythmogenic and hypertrophic cardiomyopathy in two Italian families202Lamin a/c hot spot codon 190: form various amino acid substitutions to clinical effects203Treatment with aspirin and atorvastatin attenuate cardiac injury induced by rat chest irradiation: Implication of myocardial miR-1, miR-21, connexin-43 and PKCGenomics, proteomics, metabolomics, lipidomics and glycomics206Differential phosphorylation of desmin at serines 27 and 31 drives the accumulation of preamyloid oligomers in heart failure207Potential role of kinase Akt2 in the reduced recovery of type 2 diabetic hearts subjected to ischemia / reperfusion injury208A proteomics comparison of extracellular matrix remodelling in porcine coronary arteries upon stent implantationMetabolism, diabetes mellitus and obesity211Targeting grk2 as therapeutic strategy for cancer associated to diabetes212Effects of salbutamol on large arterial stiffness in patients with metabolic syndrome213Circulating microRNA-1 and microRNA-133a: potential biomarkers of myocardial steatosis in type 2 diabetes mellitus214Anti-inflammatory nutrigenomic effects of hydroxytyrosol in human adipocytes - protective mechanisms of mediterranean diets in obesity-related inflammation215Alterations in the metal content of different cardiac regions within a rat model of diabetic cardiomyopathyTissue engineering218A novel conductive patch for application in cardiac tissue engineering219Establishment of a simplified and improved workflow from neonatal heart dissociation to cardiomyocyte purification and characterization220Effects of flexible substrate on cardiomyocytes cell culture221Mechanical stretching on cardiac adipose progenitors upregulates sarcomere-related genes. Cardiovasc Res 2016. [DOI: 10.1093/cvr/cvw135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Polarization effects on the electric properties of urea and thiourea molecules in solid phase. J Chem Phys 2016; 143:234503. [PMID: 26696062 DOI: 10.1063/1.4937481] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We present theoretical results for the dipole moment, linear polarizability, and first hyperpolarizability of the urea and thiourea molecules in solid phase. The in-crystal electric properties were determined by applying a supermolecule approach in combination with an iterative electrostatic scheme, in which the surrounding molecules are represented by point charges. It is found for both urea and thiourea molecules that the influence of the polarization effects is mild for the linear polarizability, but it is marked for the dipole moment and first hyperpolarizability. The replacement of oxygen atoms by sulfur atoms increases, in general, the electric responses. Our second-order Møller-Plesset perturbation theory based iterative scheme predicts for the in-crystal dipole moment of urea and thiourea the values of 7.54 and 9.19 D which are, respectively, increased by 61% and 58%, in comparison with the corresponding isolated values. The result for urea is in agreement with the available experimental result of 6.56 D. In addition, we present an estimate of macroscopic quantities considering explicit unit cells of urea and thiourea crystals including environment polarization effects. These supermolecule calculations take into account partially the exchange and dispersion effects. The results illustrate the role played by the electrostatic interactions on the static second-order nonlinear susceptibility of the urea crystal.
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Isotropic magnetic shielding constants of retinal derivatives in aprotic and protic solvents. J Chem Phys 2013; 139:094502. [PMID: 24028122 DOI: 10.1063/1.4819694] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We investigate the nuclear isotropic shielding constants σ((13)C) and σ((17)O) of isomers of retinoic acid and retinal in gas-phase and in chloroform, acetonitrile, methanol, and water solutions via Monte Carlo simulation and quantum mechanics calculations using the GIAO-B3LYP∕6-311++G(2d,2p) approach. Electronic solute polarization effects due to protic and aprotic solvents are included iteratively and play an important role in the quantitative determination of oxygen shielding constants. Our MP2∕6-31G+(d) results show substantial increases of the dipole moment of both retinal derivatives in solution as compared with the gas-phase results (between 22% and 26% in chloroform and between 55% and 99% in water). For the oxygen atoms the influence of the solute polarization is mild for σ((17)O) of hydroxyl group, even in protic solvents, but it is particularly important for σ((17)O) of carbonyl group. For the latter, there is a sizable increase in the magnitude with increasing solvent polarity. For the carbon atoms, the solvent effects on the σ((13)C) values are in general small, being more appreciable in carbon atoms of the polyene chain than in the carbon atoms of the β-ionone ring and methyl groups. The results also show that isomeric changes on the backbones of the polyene chains have marked influence on the (13)C chemical shifts of carbon atoms near to the structural distortions, in good agreement with the experimental results measured in solution.
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A theoretical investigation of electric properties of L-arginine phosphate monohydrate including environment polarization effects. J Chem Phys 2011; 133:144103. [PMID: 20949983 DOI: 10.1063/1.3501237] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The dipole moment (μ), linear polarizability (α), and first hyperpolarizability (β(tot)) of the asymmetric unit of L-arginine phosphate (LAP) monohydrate crystal are investigated using the supermolecule approach in combination with an iterative electrostatic polarization scheme. Environment polarization effects are attained by assuring the convergence of the dipole moment of LAP embedded in the polarization field of the surrounding molecules whose atomic sites are treated as point charges. The results obtained show that in the presence of the embedding charges, the value of μ is increased by 9% but the static values of α and β(tot) are decreased, respectively, by 3% and 13%, as compared with the isolated situation. The MP2/6-311+G(d) model predicts for the in-crystal dipole moment the converged value of 33 D, in good concordance with the available experimental result of 32 D. Our estimates for the converged results of α and β(tot) are, respectively, 22.51×10(-24) and 5.01×10(-30) esu. Dispersion effects are found to have a small impact on the nonlinear optical responses of LAP in the visible region. In addition, MP2/6-311G results obtained for β(tot) by using isolated and embedded LAP dimers show that crystal packing effects have a significant contribution of the electrostatic interactions. Our results suggest that the role of the crystal environment is to minimize the effects of the intermolecular interactions in the electric properties. That is, μ and β(tot) gain a more additive character in the presence of the field of the embedding charges. This is specially marked for β(tot).
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Quantitative hemodynamic analysis of brain aneurysms at different locations. AJNR Am J Neuroradiol 2009; 30:1507-12. [PMID: 19406766 DOI: 10.3174/ajnr.a1600] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Studies have shown that the occurrence of brain aneurysms and risk of rupture vary between locations. However, the reason that aneurysms at different branches of the cerebral arteries have different clinical presentations is not clear. Because research has indicated that aneurysm hemodynamics may be one of the important factors related to aneurysm growth and rupture, our aim was to analyze and compare the flow parameters in aneurysms at different locations. MATERIALS AND METHODS A total of 24 patient-specific aneurysm models were constructed by using 3D rotational angiographic data for the hemodynamic simulation. Previously developed computational fluid dynamics software was applied to each aneurysm to simulate the blood-flow properties. Hemodynamic data at peak pulsatile flow were recorded, and wall shear stress (WSS) and flow rate in the aneurysms and parent arteries were quantitatively compared. To validate our method, a comparison with a previously reported technique was also performed. RESULTS WSS and flow rate in the aneurysms at the peak of the cardiac cycle were found to differ in magnitude between different locations. Multiple comparisons among locations showed higher WSS and flow rate in middle cerebral artery aneurysms and lower WSS and flow rate in basilar artery and anterior communicating artery aneurysms. CONCLUSIONS We observed changes in hemodynamic values that may be related to aneurysm location. Further study of aneurysm locations with a large number of cases is needed to test this hypothesis.
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Hemodynamic patterns of anterior communicating artery aneurysms: a possible association with rupture. AJNR Am J Neuroradiol 2009; 30:297-302. [PMID: 19131411 DOI: 10.3174/ajnr.a1323] [Citation(s) in RCA: 134] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE The anterior communicating artery (AcomA) is a predilect location of aneurysms which typically carry higher rupture risks than other locations in the anterior circulation. The purpose of this study was to characterize the different flow types present in AcomA aneurysms and to investigate possible associations with rupture. MATERIALS AND METHODS Patient-specific computational models of 26 AcomA aneurysms were constructed from 3D rotational angiography images. Bilateral images were acquired in 15 patients who had both A1 segments of the anterior cerebral arteries, and models of the whole anterior circulation were created by fusing the reconstructed left and right arterial trees. Computational fluid dynamics simulations were performed under pulsatile flow conditions measured on a healthy subject. Visualizations of flow velocity, instantaneous streamlines, and wall shear stress (WSS) were performed. These were analyzed for flow patterns, size of the impaction zone, and peak WSS and then correlations were made with prior history of rupture. RESULTS Aneurysms with small impaction zones were more likely to have ruptured than those with large impaction zones (83% versus 63%). Maximum intra-aneurysmal WSS (MWSS) for the unruptured aneurysms ranged from 10 to 230 dyne/cm(2) (mean, 114 dyne/cm(2)) compared with ruptured aneurysms, which ranged from 35 to 1500 dyne/cm(2) (mean, 271 dyne/cm(2)). This difference in MWSS was statistically significant at 90% confidence levels (P = .10). CONCLUSIONS Aneurysms with small impaction zones, higher flow rates entering the aneurysm, and elevated MWSS are associated with a clinical history of previous rupture.
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BIOMECHANICAL ANALYSIS OF AN INCITING EVENT OF ANKLE SPRAIN IN BASKETBALL PLAYERS. J Biomech 2008. [DOI: 10.1016/s0021-9290(08)70453-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Abstract
Subject-specific computational and experimental models of hemodynamics in cerebral aneurysms require the specification of physiologic flow conditions. Because patient-specific flow data are not always available, researchers have used 'typical' or population average flow rates and waveforms. However, in order to be able to compare the magnitude of hemodynamic variables between different aneurysms or groups of aneurysms (e.g. ruptured versus unruptured) it is necessary to scale the flow rates to the area of the inflow artery. In this work, a relationship between flow rates and vessel areas is derived from phase-contrast magnetic resonance measurements in the internal carotid arteries and vertebral arteries of normal subjects.
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Retention of inorganic arsenic by coryneform mutant strains. WATER RESEARCH 2007; 41:531-42. [PMID: 17204300 DOI: 10.1016/j.watres.2006.11.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2006] [Revised: 10/19/2006] [Accepted: 11/07/2006] [Indexed: 05/13/2023]
Abstract
The natural resistance mechanisms of corynebacteria to respond to the environments containing high levels of arsenic were successfully adopted to develop inexpensive and selective extractants for submicrogram amounts of arsenic. Kinetic and equilibrium characteristics were evaluated, and a preliminary exploration of the capability of these strains to be used for arsenic speciation was also made in this work. Three kinetics models were used to fit the experimental data. It was found that the pseudo-first-order kinetics model was not quite adequate to describe the retention process, while the intraparticle diffusion and the pseudo-second-order kinetics models provide the best fits. The equilibrium isotherm showed that the retention of arsenic was consistent with the Langmuir equation and that the Freundlich and Dubinin-Radushkevich models provided poorer fits to the experimental data. The maximum effective retention capacity for arsenic was about 15.4 ng As/mg biomass. The amount of arsenic retained was directly measured in the biomass by forward planning a slurry electrothermal atomic absorption spectrometric procedure.
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Patient-specific computational fluid dynamics modeling of anterior communicating artery aneurysms: a study of the sensitivity of intra-aneurysmal flow patterns to flow conditions in the carotid arteries. AJNR Am J Neuroradiol 2006; 27:2061-8. [PMID: 17110667 PMCID: PMC7977194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
BACKGROUND AND PURPOSE The purpose of this study was to investigate the effects of unequal physiologic flow conditions in the internal carotid arteries (ICAs) on the hemodynamics of anterior communicating artery aneurysms. METHODS Patient-specific computational fluid dynamics models of 2 cerebral aneurysms were constructed from bilateral 3D rotational angiograms. The flow dynamics of the aneurysm sac were analyzed under the effect of unequal mean flows, phase shifts, and waveforms between the ICAs. A total of 9 simulations were performed for each patient; cine flow velocity simulations and unsteady wall shear stress (WSS) maps were created for each flow condition. Time-dependent curves of average WSS magnitude over selected regions on the aneurysms were constructed. RESULTS Mean flow unbalances in the feeding vessels tended to shift the regions of elevated WSS towards the dominating inflow jet and to change the magnitude of the WSS peaks. The overall qualitative appearance of the WSS distribution and velocity simulations was not substantially affected. Phase and waveform asymmetry increased the temporal complexity of the hemodynamic patterns and tended to destabilize the flow pattern. CONCLUSIONS Differences in the relative phase and waveform shape in ICAs can significantly affect the complexity and stability of the hemodynamic force distributions. The magnitude of these effects is related to the geometry of the aneurysm and the feeding vessels. Conditions affecting the flow characteristics in the parent arteries of cerebral aneurysms with more than 1 avenue of inflow should be incorporated into flow models.
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Computational fluid dynamics modeling of intracranial aneurysms: effects of parent artery segmentation on intra-aneurysmal hemodynamics. AJNR Am J Neuroradiol 2006; 27:1703-9. [PMID: 16971618 PMCID: PMC8139802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
PURPOSE The purpose of this study is to show the influence of the upstream parent artery geometry on intraaneurysmal hemodynamics of cerebral aneurysms. METHODS Patient-specific models of 4 cerebral aneurysms (1 posterior communicating artery [PcomA], 2 middle cerebral artery [MCA], and 1 anterior communicating artery [AcomA]) were constructed from 3D rotational angiography images. Two geometric models were constructed for each aneurysm. One model had the native parent vessel geometry; the second model was truncated approximately 1 cm upstream from the aneurysm, and the parent artery replaced with a straight cylinder. Corresponding finite element grids were generated and computational fluid dynamics simulations were carried out under pulsatile flow conditions. The intra-aneurysmal flow patterns and wall shear stress (WSS) distributions were visualized and compared. RESULTS Models using the truncated parent vessel underestimated the WSS in the aneurysms in all cases and shifted the impaction zone to the neck compared with the native geometry. These effects were more pronounced in the PcomA and AcomA aneurysms where upstream curvature was substantial. The MCA aneurysm with a long M1 segment was the least effected. The more laminar flow pattern within the parent vessel in truncated models resulted in a less complex intra-aneurysmal flow patterns with fewer vortices and less velocity at the dome. CONCLUSIONS Failure to properly model the inflow stream contributed by the upstream parent artery can significantly influence the results of intra-aneurysmal hemodynamic models. The upstream portion of the parent vessel of cerebral aneurysms should be included to accurately represent the intra-aneurysmal hemodynamics.
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Abstract
Several podophyllotoxin derivatives modified in the A, B, C, D and E rings were prepared from podophyllotoxin and methyl isoxazopodophyllic acid and evaluated for their cytotoxicity on several neoplastic cell lines. Chemical transformations performed on these compounds have yielded derivatives more potent and more selective that the parent compound. Most of the compounds maintained their cytotoxicity at the microM level. Distribution, biosynthesis, production, biotechnology, applications and synthesis have also been reviewed.
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Fourier-transform infrared spectroscopic study of the interactions of selenium species with living bacterial cells. Anal Bioanal Chem 2004; 378:1601-7. [PMID: 15214423 DOI: 10.1007/s00216-004-2494-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
UNLABELLED A study of the interactions of several selenium species with living bacterial cells was carried out by Fourier-transform infrared (FT-IR) spectroscopy. Bacterial cells consisted of an Escherichia coli strain (K-12) cultivated in a growth medium based on glucose contaminated with selenium species. Equilibrium between the analyte in the solution and the extraction medium was established, and then the effects of selenium species upon the external membrane of the living bacterial cells were characterized by performing FT-IR spectroscopy of whole cells. The presence of the toxicants at various concentrations in the culture medium had an effect on the FT-IR spectra, and the concentration of the selenium species was determined directly in the biomass by FT-IR spectroscopy. The intensity ratios between several absorption lines, which varied as a function of the concentration of the selenium species, were used as the analytical signal. ELECTRONIC SUPPLEMENTARY MATERIAL Supplementary material is available for this article if you access the article at http://dx.doi.org/10.1007/s00216-004-2494-4. A link in the frame on the left on that page takes you directly to the supplementary material.
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The distribution of toluene in intercalation complexes of a vermiculite and alkyl trimethylammonium bromides. J Colloid Interface Sci 2003; 267:265-71. [PMID: 14583201 DOI: 10.1016/s0021-9797(03)00111-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Neutron diffraction and isotopic labeling have been used to determine the distribution of toluene sorbed into the interlamellar space of complexes of vermiculite with alkyl trimethylammonium bromide complex of alkyl chain lengths C(12), C(14), and C(16) and in a mixed C(12)/C(16) complex. The toluene remains in a liquid-like form and fills and swells the interlamellar space space up to a point where there remains a small amount of overlap of the alkyl chains of the surfactant. If the complex is between vermiculite and one surfactant only this results in the toluene concentration being reduced in the center of the interlamellar space, with maxima on either side. On the other hand, in a complex of mixed-length surfactants, the toluene distribution reaches its maximum at the center of the interlamellar space.
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[Influence of different pharmacological agents in the ex vivo proliferation of mesothelial cells obtained from the peritoneal effluent of patients treated with peritoneal dialysis]. Nefrologia 2003; 23:243-51. [PMID: 12891939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/04/2023] Open
Abstract
UNLABELLED Mesothelial cells (MC) are the first peritoneal membrane barrier in contact with dialysate. The aim of this study was to analyze the in vitro capacity of different pharmacological agents to modify the ex vivo proliferation of MC obtained from the peritoneal effluent of patients treated with peritoneal dialysis (PD). MATERIAL AND METHODS Thirty cultures of MC taken from nocturnal peritoneal effluent were performed. After identification, MC are subcultured in 24 multi-well plates, adding the different exogenous agents. Proliferative capacity and cell morphology were estimated on day 16th of culture. The agents evaluated were insulin, IGF-1, tamoxifen, labetalol, carvedilol, enalapril and losartan. RESULTS Insulin shows a dose-dependent effect on MC growth, with a limit that is stimulated by the addition of fetal bovine serum (FBS). Concentrations higher than 100 micrograms/ml, are not associated with further growth, even with cell damage. In contrast, the wide range of IGF-1 dose used did not affect to MC proliferation. Tamoxifen causes negative effects on MC growth just a very high doses, not resembling doses in clinical practice. Labetalol does not modify MC proliferation used under therapeutic calculated range. However, concentrations higher than 40 micrograms/ml showed a negative influence on growth, behaving as lethal doses that over 100 micrograms/ml. The addition of FBS attenuates this effect. These effects were very similar to that caused by carvedilol addition. Enalapril and losartan act as antiproliferative agents for MC. This effect is potentiated with angiotensin II, reaching lethal concentrations increasing the dose. In conclusion, mesothelial cell growth ex vivo taken from nocturnal peritoneal effluent on PD patients is an useful tool to explore the effects of any pharmacological agent on the biology of the cell of the peritoneum. The agents used had any influence in the proliferation capacity of mesothelial cells.
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Abstract
In this brief contribution we demonstrate that 1H and 2H NMR spectroscopy can be an effective method of investigating adsorption from liquids at the solid-liquid interface. The method is illustrated here with the adsorption of a simple alkane adsorbed on graphite, in particular the system n-dodecane and graphite at coverages of 1 and 5 monolayers. Static single-pulse proton nuclear magnetic resonance and static quadrupolar echo deuterium nuclear magnetic resonance spectra were recorded for both coverages. The experimental NMR results presented here show features clearly consistent with earlier calorimetric and neutron scattering work and demonstrate the formation of solid adsorbed layers that coexist with the bulk adsorbate with both isotopes. This ability to probe both deuterated and protonated materials simultaneously illustrates that this experimental approach can be readily extended to investigate the adsorption behaviour of multicomponent mixtures.
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Nickel as a Chemical Modifier for Sensitivity Enhancement and Fast Atomization Processes in Electrothermal Atomic Absorption Spectrometric Determination of Cadmium in Biological and Environmental Samples. ANAL SCI 2003; 19:1631-6. [PMID: 14696927 DOI: 10.2116/analsci.19.1631] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
A systematic study of the efficiency of protons, Ni, Pd and Th as chemical modifiers for the determination of cadmium by electrothermal atomic absorption spectrometry (ETAAS) using fast temperature programs was made for platform atomization. A comparison was made in terms of the salt type, absorbance-time profiles and elimination of the sodium chloride interference. The results were adapted to develop a method for the ETAAS determination of cadmium in biological and environmental samples. The highest sensitivity to determine cadmium in biological and environmental samples was obtained using nickel (together with protons) as a chemical modifier. The accuracy of the method was tested by the determination of cadmium in different certified reference materials. The best detection limit and the characteristic mass of Cd were found to be 0.03 ng mL(-1) and 0.35 pg, respectively.
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Effect of bicarbonate/lactate peritoneal dialysis solutions on human mesothelial cell proliferation ex vivo. ADVANCES IN PERITONEAL DIALYSIS. CONFERENCE ON PERITONEAL DIALYSIS 2002; 17:37-41. [PMID: 11510293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
Peritoneal membrane suffers structural and functional changes over time on peritoneal dialysis (PD)--in part, owing to the dialysis solutions currently used. Low pH seems to be an important element associated with solution bioincompatibility. Bicarbonate-containing fluids open new perspectives on this issue. The present study compared the effects of bicarbonate/lactate (Bic/Lac) solution (25 mmol/L bicarbonate, 15 mmol/L lactate) and lactate (Lac) solution (40 mmol/L lactate) on mesothelial cell (MC) growth in culture. Eight stable PD patients were asked to collect peritoneal effluent from an 8-hour dwell on two separate days, within an interval shorter than one week. For the first dwell, Lac solution was infused; for the second dwell, Bic/Lac solution was instilled. Human MCs were isolated from the effluent, seeded in 25-cm2 tissue culture flasks, and grown ex vivo. Morphology of the cells was also evaluated. In all effluents, MCs were present in mean amounts of 26,939 +/- 21,267 cells (Bic/Lac) and 25,986 +/- 15,286 cells [Lac, p = nonsignificant (NS)]. Morphology of the MCs was similar with both solutions (87.5% typical). After initial culture, MCs from 6 patients using Bic/Lac (75%) and 3 patients using Lac (37.5%) reached confluence. At this time, the number of MCs from the 3 patients who showed MC growth with both solutions was slightly higher with Bic/Lac-buffered fluid (Lac: 1,154,125 +/- 213,333 cells; Bic/Lac: 1,198,291 +/- 806,713 cells). To summarize: 3 patients showed MC growth under both solutions; 3 patients showed MC growth only under Bic/Lac solution; and 2 patients showed no MC growth at all. After cells were seeded in 24-well plates, the MC growth curve was performed in 4 cases of Bic/Lac solution use and in 3 cases of Lac solution use. Although no significant differences were observed between the solutions, the final number of MCs obtained was higher with Bic/Lac solution use. In conclusion, MCs released into peritoneal effluent under bicarbonate/lactate-buffered peritoneal dialysis solution are associated with a greater ex vivo proliferation capacity than those released under lactate solution in the same patient. This finding may demonstrate better biocompatibility for Bic/Lac solution.
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Structure and ultrastructure of leaf and calyx glands in Galphimia brasiliensis (Malpighiaceae). AMERICAN JOURNAL OF BOTANY 2001; 88:1935-1944. [PMID: 21669626 DOI: 10.2307/3558420] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The present study describes the anatomical structure of calyx and leaf glands in Galphimia brasiliensis and analyzes the mechanism of secretion. The glands are marginal and suprabasal, cup-shaped, sessile, and scarcely visible with the naked eye. Light microscopy reveals the following features: a thin, smooth cuticle; unistratified secretory cells; subglandular parenchyma; and vascular bundle supply composed of phloem and xylem with abundant druses of calcium oxalate. Transmission electron microscopy reveals the presence of secretory cells with conspicuous nuclei, dense cytoplasm, lipid droplets, numerous vesicles, mitochondria, Golgi, rough endoplasmic reticulum (RER), and elongated plastids with osmiophilic contents. The secretion reaches the apoplastic space and accumulates beneath the cuticle. Finally, the viscous, translucent exudate is eliminated by mechanical rupture of the cuticle. Histochemical analysis confirms that lipids are the main constituent. Small amounts of polysaccharides were also identified.
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Distortion-tolerant three-dimensional object recognition with digital holography. APPLIED OPTICS 2001; 40:3887-3893. [PMID: 18360422 DOI: 10.1364/ao.40.003887] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
We present a technique to implement three-dimensional (3-D) object recognition based on phase-shift digital holography. We use a nonlinear composite correlation filter to achieve distortion tolerance. We take advantage of the properties of holograms to make the composite filter by using one single hologram. Experiments are presented to illustrate the recognition of a 3-D object in the presence of out-of-plane rotation and longitudinal shift along the z axis.
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[Effectiveness of the abdominal CT in diagnosis of the viscero-abdominal fat accumulation in HIV patients treated with protease inhibitors]. ANALES DE MEDICINA INTERNA (MADRID, SPAIN : 1984) 2001; 18:452-3. [PMID: 11589092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
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Intercellular contact-dependent survival of human A549, NCI-H596 and NCI-H520 non-small cell lung carcinoma cell lines. Braz J Med Biol Res 2001; 34:1007-13. [PMID: 11471039 DOI: 10.1590/s0100-879x2001000800006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
In the present study, we examined the relationship between cell phenotype and cell survival of three human non-small cell lung carcinoma cell lines (A549, NCI-H596 and NCI-H520). Cells in exponential growth at various densities were incubated for 24 h at 37 degrees C in a 5% CO2 humidified atmosphere and then exposed to UV radiation for 1 min (256 nm, 40 W, source-to-target distance 100 cm). After two days the surviving cells were quantified by sulforhodamine beta staining and DNA fragmentation assay. The differences in UV sensitivity at 60 x 10(3) cells/cm2 among the cell lines were not related to the proliferative state of the cells but to the extent of intercellular contact. In contrast to A549 and NCI-H596, irradiated NCI-H520 cells presented lower DNA fragmentation and an aggregated cell culture phenotype even prior to confluence, suggesting that a contact-effect mechanism provides further protection against UV radiation.
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Vascular endothelial growth factor (VEGF) levels in peritoneal dialysis effluent. J Nephrol 2001; 14:270-4. [PMID: 11506249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
BACKGROUND Long-term peritoneal dialysis (PD) patients who develop peritoneal ultrafiltration failure have an abnormally large number of capillaries and sclerotic changes in peritoneal biopsy. Peritoneal vascular endothelial growth factor (VEGF) production has been suggested to explain the higher levels in peritoneal effluent than in plasma. The high effluent VEGF levels have been related to peritoneal changes consisting of increased permeability to small molecules. To further analyze the relationship between peritoneal neoangiogenesis induced by VEGF and peritoneal transport, we studied peritoneal effluent VEGF levels in active PD patients. METHODS VEGF levels were determined in serum and plasma, and in peritoneal effluent (PE) after 4, 8 and 15 h dwell times. RESULTS PE VEGF levels were 58.6+/-33.7 pg/mL, with a mean VEGF D/P ratio of 0.45+/-0.29 (range 0.06-0.93). In low-transport patients (n = 7) this ratio did not differ from high-average ones (n=5) (0.48+/-0.3 and 0.41+/-0.1, NS). In multivariate analysis, the VEGF D/P ratio showed no correlation with the independent variables included in this study. VEGF levels were higher in 15 h than in 8 h effluent; so the VEGF D/P ratios were higher as well. Regression analysis showed a direct correlation between PEVEGF levels and dwell time (r: 0.57, p = 0.03), but not between VEGF D/P ratio and dwell time. PEVEGF levels directly correlated with effluent protein content. Regression analysis showed no correlation between PEVEGF levels and age, time on PD, days of peritonitis, urea and creatinine-mass transfer coefficients, ultrafiltration capacity, and accumulated glucose dose. Multivariate regression analysis showed correlation only between PEVEGF levels and dwell time, but not with the other independent variables. CONCLUSIONS This study confirms that VEGF is present in fresh PE from PD patients at levels that suggest local production and filtration from plasma. Peritoneal effluent VEGF levels are not significantly associated with peritoneal functional parameters and background, and seem to be influenced by ultrafiltration in a dilution process. We believe that the role of VEGF in peritoneal pathophysiology is part of a complex relationship involving multiple peritoneal structures and other growth factors, including local counteracting factors for VEGF that regulate neoangiogenesis.
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Separation of amniotic membranes after amniocentesis in an individual with the classic form of EDS and haploinsufficiency for COL5A1 expression. AMERICAN JOURNAL OF MEDICAL GENETICS 2001; 101:174-7. [PMID: 11391664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
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Abstract
A new series of diterpenylquinone/hydroquinones has been prepared by Diels-Alder cycloaddition between three labdanic diterpenoids (myrceocommunic acid, methyl myrceocommunate, and myrceocommunyl acetate) and p-benzoquinone or 1,4-naphthoquinone. Influences of the quinone/hydroquinone fragment and other structural features, such as the different functionalities in the terpenic core, are considered in relation to the cytotoxicity toward neoplastic cells and the selectivity of these diterpenylnaphthoquinones/hydroquinones and anthraquinones. Several compounds showed IC50 values under the micromolar level, and four of these derivatives were evaluated at the NCI screening panel. The results showed an important selectivity toward renal cancer lines, identifying these compounds as a very promising group of antineoplastics.
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Abstract
The lignan family of natural products includes compounds with important antineoplastic and antiviral properties such as podophyllotoxin and two of their semisynthetic derivatives, etoposide and teniposide. The latter are included in a wide variety of cancer chemotherapy protocols. Due to these biological activities, lignans, and especially cyclolignans, have been the objective of numerous studies focused to prepare better and safer anticancer drugs. The mechanism by which podophyllotoxin blocks cell division is related to its inhibition of microtubule assembly in the mitotic apparatus. However, etoposide and teniposide were shown not to be inhibitors of microtubule assembly which suggested that their antitumor properties were due to another mechanism of action, via their interaction with DNA and inhibition of DNA topoisomerase II. Other podophyllotoxin derivatives has also been reported which retained or even improved the cytotoxic activity, but these were weak inhibitors of topoisomerase II in vitro; the data revealed that such analogs exhibit a different, as yet unknown, mechanism of action. The main deficiency of these compounds is their cytotoxicity for normal cells and hence side effects derived from their lack of selectivity against tumoral cells. In this regard it is necessary to investigate and prepare new more potent and less toxic analogs, that is, with better therapeutic indices. It is well accepted from structure-activity studies in this field that the trans-lactones are more potent as antineoplastics than the cis-lactones. Not only the configuration of the D ring is an important factor for high cytotoxic activity, but also a quasi-axial arrangement of the E ring is necessary. On this basis, studies on lignans have been addressed to modify the lactone moiety and prepare analogs with heteroatoms at different positions of the cyclolignan skeleton. Our group has been working during the last few years on chemical transformations of podophyllotoxin and analogs and we have prepared a large number of cyclolignan derivatives some of which display potent antiviral, immunosuppressive and cytotoxic activities. We have reported several new cytotoxic agents with nitrogen atoms at C-7 or C-9 or at both C-7 and C-9: imine derivatives, oxime derivatives, pyrazoline-, pyrazo- and isoxazoline-fused cyclolignans. At present, we are preparing mainly new compounds by modifications of the A and E cyclolignan-rings. They are being tested on cultures of different tumoral cell lines (P-388 murine leukemia, A-549 human lung carcinoma, HT-29 human colon carcinoma and MEL-28 human melanoma) and some of them have shown an interesting and selective cytotoxicity.
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Spontaneous VEGF production by cultured peritoneal mesothelial cells from patients on peritoneal dialysis. Perit Dial Int 2000; 20:798-801. [PMID: 11216582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023] Open
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Icodextrin effluent leads to a greater proliferation than glucose effluent of human mesothelial cells studied ex vivo. Perit Dial Int 2000; 20:742-7. [PMID: 11216569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023] Open
Abstract
OBJECTIVE To compare the effect of glucose (Glu) and icodextrin (Ico) dialysate on in vitro culture of mesothelial cells (MC) from peritoneal dialysis (PD) patients. DESIGN Prospective, controlled comparative study on the effects of two PD solutions. SETTING A tertiary-care public university hospital. PATIENTS Sixteen PD patients regularly using Glu dialysate were asked to collect an 8-hour dwell peritoneal effluent on 2 different days, with an interval shorter than 7 days. In the first collection, 2.27% Glu solution and in the last, 7.5% Ico solution was infused. Human MC were isolated from the nocturnal peritoneal effluent bags and grown ex vivo. MAIN OUTCOME MEASURES Mesothelial cell proliferative capacity ex vivo. RESULTS Mesothelial cells were present in all patient dialysates except that of a single patient's Glu dialysate. The number of MC drained was similar with both solutions. After the initial culture reached confluence, MC were identified in 14 and 12 patients receiving Ico and Glu, respectively. However, in 1 patient using Ico and in 2 using Glu, the MC count at this stage was so low that further subculture could not be performed. Cells from Ico-derived solutions exhibited a higher degree of proliferation than cells from Glu-derived solutions. The morphology of MC was also different. Cells from drained effluent were typical in 11 patients using Glu solution in contrast with 14 patients using Ico. At confluence, the percentages of typical appearance were 50% and 92.9% (p < 0.05) in Glu and Ico respectively. CONCLUSIONS Mesothelial cells taken from icodextrin effluent show a greater proliferation ex vivo than those taken from glucose effluent.
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Gastric necrosis and perforation as a complication of splenectomy. Case report and related references. ARQUIVOS DE GASTROENTEROLOGIA 2000; 37:227-30. [PMID: 11460603 DOI: 10.1590/s0004-28032000000400008] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Necrosis of the stomach after isolated splenectomy with the formation of gastrocutaneous fistula is a rare event that occurs in less than 1% of splenectomies. It is more frequent when the removal of the spleen is done because of hematological diseases. Its mortality index can reach 60% and its pathogenesis is controversial, as it may be attributed both to direct trauma of the gastric wall and to ischemic phenomena. Although the stomach may exhibit exuberant arterial blood irrigation, anatomical variations can cause a predisposition towards the appearance of potentially ischemic areas, especially after ligation of the short gastric vessels around the major curvature of the stomach. Once this is diagnosed in the immediate postoperative period, it becomes imperative to reoperate. The surgical procedure will depend on the conditions of the peritoneal cavity and patient's clinic status. The objective of this study was to report on the case of a patient submitted to splenectomy because of closed abdominal traumatism, who then presented peritonitis and percutaneous gastric fistula in the post-operative period. During the second operation, perforations were identified in anterior gastric wall where there had been signs of vascular stress. The lesion was sutured after revival of its borders, and the patient had good evolution. Prompt diagnosis and immediate treatment of this unusual complication are needed to reduce its high mortality rate.
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Calculated Infrared, Raman, and Rayleigh Properties of the CO(3) Molecule. JOURNAL OF MOLECULAR SPECTROSCOPY 2000; 202:281-284. [PMID: 10877958 DOI: 10.1006/jmsp.2000.8129] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Properties associated with the infrared, Rayleigh, and Raman spectra of the CO(3) molecule are calculated by the Hartree-Fock and Møller-Plesset perturbation theory methods. Vibrational frequencies and infrared activities are found to be in agreement with the experiment and previous calculations. The values obtained for the Raman spectrum show a very sensitive dependence to the treatment of electron correlation. The OCO wag normal mode, unobserved in the IR experiment, is predicted to have a very small Raman scattering activity. Copyright 2000 Academic Press.
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Abstract
Several aldehydes related to methyl 9-deoxy-9-oxo-alpha-apopicropodophyllate, a selective antitumour agent against the HT-29 colon carcinoma, have been prepared and evaluated for their cytotoxic activities on four neoplastic cell lines (P-388, A-549, HT-29 and MEL-28). All of them lacked the lactone ring but maintained their cytotoxicity at, or under, the microM level.
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[Methods to assess the ex vivo growth capacity of mesothelial cells obtained directly from peritoneal effluent]. Nefrologia 2000; 20:277-83. [PMID: 10917005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023] Open
Abstract
The anatomical and functional integrity of mesothelial cells (MC) is necessary for peritoneal membrane stability. At present, there is no satisfactory method to assess MC function and regenerative capacity in individual peritoneal dialysis (PD) patients. MC may be cultured from peritoneal biopsy specimens, but peritoneal biopsy is an invasive procedure that cannot be performed serially. The aim of this study is to explore the feasibility of serial culture of MC from the peritoneal effluent of PD patients. Fifty-two randomly selected PD patients were studied. MC were obtained from the peritoneal effluent of nocturnal 2.27% glucose exchanges and cultured in T25 tissue culture flasks. Subconfluent MC cultures were obtained in 80.7% of patients. At this stage, the percentage of cells in the tissue cultured flask characterized as MC by morphology and immunostaining had increased to 95.5%. MC were then subcultured in multi-well culture plates, where they showed exponential cell growth until day 16. Nine (17%) patients released low numbers of MC into the effluent and MC could not be cultured to subconfluence. One additional patient released and apparently adequate number of MC that repeatedly failed to reach confluence. Patients showed the same behavior in several cultures performed. In conclusion, peritoneal MC released into peritoneal effluent are accessible for profound analysis by a culture technique. This technique opens the possibility of serial follow-up of the biology of MC individual PD patients.
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Abstract
Several prenylhydroquinones have been prepared through Diels-Alder condensation, further functionalized or degraded chemically and then evaluated for their cytotoxic activity against some neoplastic cultured cell lines. A number of them have shown IC50 values under the microM level.
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Ex vivo proliferation of mesothelial cells directly obtained from peritoneal effluent: its relationship with peritoneal antecedents and functional parameters. ADVANCES IN PERITONEAL DIALYSIS. CONFERENCE ON PERITONEAL DIALYSIS 2000; 14:19-24. [PMID: 10649684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
The peritoneal membrane requires anatomico-functional integrity to guarantee long-term stability for peritoneal dialysis (PD). Since mesothelial cells (MC) are active cells and the first part of the membrane to contact the dialysate, they are important in maintaining this stability. Mesothelial cells released daily into peritoneal effluent are able to grow in culture. This growth capacity may be related to some of the anatomicofunctional characteristics of each peritoneum. Our aim was to culture mesothelial cells taken from peritoneal effluents drained by 32 PD-stable patients, and relate this growth capacity to individual peritoneal data. Cells were taken from a residual fluid after sedimentation, washed twice with phosphate-buffered saline (PBS), and seeded into 25-cm2 tissue-culture flasks. These flasks were incubated in a humidified 5%-CO2 atmosphere. After MC confluence, cells were detached by trypsinization, passaged into 24-well plates, and finally counted. Cells were identified by morphology and immuno-histochemical characteristics. Cells from 28 out of 32 patients showed an appropriate growth in culture. Mesothelial cell confluence was reached in a mean of 18.2 +/- 8 days. After 7 days of seeding in plate wells, the cell growth showed a significant and progressive increase until day 16. Mesothelial cell growth rate was inversely related to PD duration. Neither peritonitis incidence nor other demographic characteristic were related to MC growth. Creatinine and urea mass transfer coefficients (MTC), but not ultrafiltration (UF) capacity, were significantly related to MC growth rate. In conclusion, the growth in culture of MC taken directly from PD bags is certainly possible. This growth is influenced by some of the intrinsic peritoneal characteristics derived from the peritoneal dialysis process. This tool could be useful in evaluating individual peritoneal conditions and, probably, as a method for peritoneal viability follow-up, although further research is required.
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Abstract
BACKGROUND Infants delivered by vacuum extraction or other operative techniques may be more likely to sustain major injuries than those delivered spontaneously, but the extent of the risk is unknown. METHODS From a California data base, we identified 583,340 live-born singleton infants born to nulliparous women between 1992 and 1994 and weighing between 2500 and 4000 g. One third of the infants were delivered by operative techniques. We evaluated the relation between the mode of delivery and morbidity in the infants. RESULTS Intracranial hemorrhage occurred in 1 of 860 infants delivered by vacuum extraction, 1 of 664 delivered with the use of forceps, 1 of 907 delivered by cesarean section during labor, 1 of 2750 delivered by cesarean section with no labor, and 1 of 1900 delivered spontaneously. As compared with the infants delivered spontaneously, those delivered by vacuum extraction had a significantly higher rate of subdural or cerebral hemorrhage (odds ratio, 2.7; 95 percent confidence interval, 1.9 to 3.9), as did the infants delivered with the use of forceps (odds ratio, 3.4; 95 percent confidence interval, 1.9 to 5.9) or cesarean section during labor (odds ratio, 2.5; 95 percent confidence interval, 1.8 to 3.4), but the rate of subdural or cerebral hemorrhage associated with vacuum extraction did not differ significantly from that associated with forceps use (odds ratio for the comparison with vacuum extraction, 1.2; 95 percent confidence interval, 0.7 to 2.2) or cesarean section during labor (odds ratio, 0.9; 95 percent confidence interval, 0.6 to 1.4). CONCLUSIONS The rate of intracranial hemorrhage is higher among infants delivered by vacuum extraction, forceps, or cesarean section during labor than among infants delivered spontaneously, but the rate among infants delivered by cesarean section before labor is not higher, suggesting that the common risk factor for hemorrhage is abnormal labor.
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[Tuberculosis, AIDS, and antiretroviral therapy]. Rev Clin Esp 1999; 199:858. [PMID: 10687426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
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Abstract
Mammalian cell shape is critically important to cell differentiation, apoptosis, cell division, and growth arrest. In the present study we examined the relationship among cell density, cell phenotype (which include shape and coupling) and cell survival using the human A549, H596 and H520 non-small cell lung carcinoma lines. Thus, cells from monolayers, aggregated and suspended cultures at different densities were exposed to UV-radiation and both the density and the phenotype of the cells induce shifts in cellular growth rate. Except in suspended cultures, we observed a UV-sensitivity closely related to the proliferative status of the cells. The variability of the cellular response to UV were investigated taking into account the shape and the coupling potential of the cell lines, suggesting that an intercellular-contact mechanism provides further protection against UV-radiation damage.
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CD2 and CD3 associate independently with CD5 and differentially regulate signaling through CD5 in Jurkat T cells. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1999; 163:4238-45. [PMID: 10510361] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
In T lymphocytes, the CD2 and CD5 glycoproteins are believed to be involved in the regulation of signals elicited by the TCR/CD3 complex. Here we show that CD2 and CD3 independently associate with CD5 in human PBMC and Jurkat cells. CD5 coprecipitates with CD2 in CD3-deficient cells and, conversely, coprecipitates with CD3 in cells devoid of CD2. In unstimulated CD2+ CD3+ Jurkat cells, CD5 associates equivalently with CD2 and CD3 and is as efficiently phosphorylated in CD2 as in CD3 immune complexes. However, upon activation the involvement of CD5 is the opposite in the CD2 and CD3 pathways. CD5 becomes rapidly tyrosine phosphorylated after CD3 stimulation, but is dephosphorylated upon CD2 cross-linking. These opposing effects correlate with the decrease in the activity of the SH2 domain-containing protein phosphatase 1 (SHP-1) following CD3 activation vs an enhanced activity of the phosphatase after CD2 triggering. The failure of CD5 to become phosphorylated on tyrosine residues in the CD2 pathway has no parallel with the lack of use of zeta-chains in CD2 signaling; contrasting with comparable levels of association of CD2 or CD3 with CD5, zeta associates with CD2 only residually and is nevertheless slightly phosphorylated after CD2 stimulation. The modulation of CD5 phosphorylation may thus represent a level of regulation controlled by CD2 in signal transduction mechanisms in human T lymphocytes.
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Reversible peripartum liver failure: a new perspective on the diagnosis, treatment, and cause of acute fatty liver of pregnancy, based on 28 consecutive cases. Am J Obstet Gynecol 1999; 181:389-95. [PMID: 10454689 DOI: 10.1016/s0002-9378(99)70567-3] [Citation(s) in RCA: 182] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
OBJECTIVE We sought to describe our experience with the clinical diagnosis, management, and course of patients with acute fatty liver of pregnancy. STUDY DESIGN Twenty-eight cases of acute fatty liver of pregnancy at the Los Angeles County and University of Southern California Medical Center from 1982 to June 1997 were identified, and presenting symptoms, clinical course, laboratory values, maternal complications, and neonatal outcomes were studied. RESULTS The incidence of acute fatty liver of pregnancy was 1 in 6659 births. There were no maternal deaths. Initial presentation was at an average of 37 weeks of gestation with a characteristic prodrome of malaise, nausea, vomiting, and abdominal pain. No patient was admitted with the diagnosis of acute fatty liver of pregnancy. The condition was diagnosed most commonly on the second hospital day after laboratory results indicated coagulopathy, renal insufficiency, and liver function abnormalities. One patient underwent liver biopsy at cesarean delivery. Radiologic studies did not aid with the diagnosis. Twenty-one patients were admitted in spontaneous labor, and 16 labors were complicated by abnormal fetal heart rate patterns or meconium. There was 1 stillbirth and 1 neonatal death as a result of perinatal asphyxia. Maternal morbidity consisted of hypoglycemia, infection, renal insufficiency, coagulopathy, encephalopathy, and wound complications. All patients had evidence of disseminated intravascular coagulopathy with profoundly decreased antithrombin levels. All patients recovered normal liver function post partum. CONCLUSIONS Reversible peripartum liver failure may be diagnosed and managed on the basis of clinical and laboratory criteria. With adequate support, these patients may have full recovery of hepatic function.
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Deficient proliferation of myeloid, erythroid, and multipotent progenitor cells in long-term marrow cultures from patients with aplastic anemia treated with immunosuppressive therapy. Am J Hematol 1998; 59:149-55. [PMID: 9766800 DOI: 10.1002/(sici)1096-8652(199810)59:2<149::aid-ajh8>3.0.co;2-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
By using Dexter-type long-term marrow cultures (D-LTMC), it has been shown previously that hematopoietic progenitor cells (HPC) from patients with aplastic anemia (AA) have a deficient proliferation in vitro. The studies reported to date, however, have focused exclusively on granulomonocytic progenitors and no information exists on erythroid or multipotent progenitor cells. On the other hand, in such studies, the input progenitor cell numbers were significantly below normal levels, thus suggesting that the rapid disappearance of myeloid progenitor cells from AA D-LTMC could also be due, at least in part, to their reduced number at culture onset. In the present study, we have followed the kinetics of myeloid, erythroid, and multipotent progenitors, from 24 AA patients subjected to immunosuppressive therapy (including patients that achieved complete, partial, or no remission at all), throughout a seven-week culture period. For analysis, we grouped all the patients based on their initial content of all three types of progenitors. Thus, we were able to evaluate separately the kinetics of these cells in D-LTMC from patients with normal and subnormal levels of progenitor cells. At the time of marrow sampling, most patients showed decreased levels of HPC; in fact, only 21%, 8%, and 16% of them showed normal levels of myeloid, erythroid, and multipotent progenitors, respectively. When cultured in D-LTMC, HPC from all AA patients analyzed showed a relatively fast disappearance from the cultures. Indeed, myeloid progenitors could be detected for only six weeks, whereas erythroid and multipotent progenitors disappeared from the cultures after two and one weeks of culture, respectively. In contrast, in normal marrow D-LTMC, myeloid, erythroid, and multipotent progenitors were detected for at least seven, five, and three weeks, respectively. Such a deficient proliferation was observed even in cultures of AA patients that contained normal levels of HPC at culture onset. Interestingly, no correlation was found between HPC proliferation in D-LTMC and response to treatment. Thus, the results of this study indicate the presence of a functional in vitro deficiency in the hematopoietic system of patients with AA, including those that achieved partial or complete remission after immunosuppressive treatment. Furthermore, this work suggests that such a proliferation deficiency is more pronounced in erythroid and multipotent progenitors than in their myeloid counterparts.
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