Discrimination of ß-cyclodextrin/hazelnut (Corylus avellana L.) oil/flavonoid glycoside and flavonolignan ternary complexes by Fourier-transform infrared spectroscopy coupled with principal component analysis.

The goal of the study was the discrimination of ß-cyclodextrin (ß-CD)/hazelnut (Corylus avellana L.) oil/antioxidant ternary complexes through Fourier-transform infrared spectroscopy coupled with principal component analysis (FTIR-PCA). These innovative complexes combine the characteristics of the three components and improve the properties of the resulting material such as the onsite protection against oxidative degradation of hazelnut oil unsaturated fatty acid glycerides. Also, the apparent water solubility and bioaccessibility of the hazelnut oil components and antioxidants can be increased, as well as the controlled release of bioactive compounds (fatty acid glycerides and antioxidant flavonoids, namely hesperidin, naringin, rutin, and silymarin). The appropriate method for obtaining the ternary complexes was kneading the components at various molar ratios (1:1:1 and 3:1:1 for ß-CD hydrate:hazelnut oil (average molar mass of 900 g/mol):flavonoid). The recovering yields of the ternary complexes were in the range of 51.5-85.3% and were generally higher for the 3:1:1 samples. The thermal stability was evaluated by thermogravimetry and differential scanning calorimetry. Discrimination of the ternary complexes was easily performed through the FTIR-PCA coupled method, especially based on the stretching vibrations of CO groups in flavonoids and/or CO/CC groups in the ternary complexes at 1014.6 (± 3.8) and 1023.2 (± 1.1) cm-1 along the second PCA component (PC2), respectively. The wavenumbers were more appropriate for discrimination than the corresponding intensities of the specific FTIR bands. On the other hand, ternary complexes were clearly distinguishable from the starting ß-CD hydrate along the first component (PC1) by all FTIR band intensities and along PC2 by the wavenumber of the asymmetric stretching vibrations of the CH groups at 2922.9 (± 0.4) cm-1 for ternary complexes and 2924.8 (± 1.4) cm-1 for ß-CD hydrate. The first two PCA components explain 70.38% from the variance of the FTIR data (from a total number of 26 variables). Other valuable classifications were obtained for the antioxidant flavonoids, with a high similarity for hesperidin and naringin, according to FTIR-PCA, as well as for ternary complexes depending on molar ratios. The FTIR-PCA coupled technique is a fast, nondestructive and cheap method for the evaluation of quality and similarity/characteristics of these new types of cyclodextrin-based ternary complexes having enhanced properties and stability.

The Impact of Composites with Silicate-Based Glasses and Gold Nanoparticles on Skin Wound Regeneration.

The silver content of the skin regeneration ointments can influence its regeneration process but in the meantime, it can take the benefit of the antibacterial properties of silver by avoiding the bacterial infection of an open wound. In the current study, the skin healing and regeneration capacity of bioactive glass with spherical gold nanocages (BGAuIND) in the Vaseline ointments were evaluated in vivo comparing the bioactive glass (BG)-Vaseline and bioactive glass with spherical gold (BGAuSP)-Vaseline ointments. Spherical gold nanocages are stabilized with silver and as a consequence the BGAuIND exhibits great antibacterial activity. Histological examination of the cutaneous tissue performed on day 8 indicates a more advanced regeneration process in rats treated with BGAuSP-Vaseline. The histopathological examination also confirms the results obtained after 11 days post-intervention, when the skin is completely regenerated at rats treated with BGAuSP-Vaseline compared with the others groups where the healing was incomplete. This result is also confirmed by the macroscopic images of the evolution of wounds healing. As expected, the silver content influences the wound healing process but after two weeks, for all of the post-interventional trials from the groups of rats, the skin healing was completely.

Obesity increases hepatic glycine dehydrogenase and aminomethyltransferase expression while dietary glycine supplementation reduces white adipose tissue in Zucker diabetic fatty rats.

Obesity is associated with altered glycine metabolism in humans. This study investigated the mechanisms regulating glycine metabolism in obese rats. Eight-week-old Zucker diabetic fatty rats (ZDF; a type-II diabetic animal model) received either 1% glycine or 1.19% L-alanine (isonitrogenous control) in drinking water for 6 weeks. An additional group of lean Zucker rats also received 1.19% L-alanine as a lean control. Glycine concentrations in serum and liver were markedly lower in obese versus lean rats. Enteral glycine supplementation restored both serum and hepatic glycine levels, while reducing mesenteric and internal white fat mass compared with alanine-treated ZDF rats. Blood glucose and non-esterified fatty acid (NEFA) concentrations did not differ between the control and glycine-supplemented ZDF rats (P > 0.10). Both mRNA and protein expression of aminomethyltransferase (AMT) and glycine dehydrogenase, decarboxylating (GLDC) were increased in the livers of obese versus lean rats (P < 0.05). In contrast, glycine cleavage system H (GCSH) hepatic mRNA expression was downregulated in obese versus lean rats, although there was no change in protein expression. These findings indicate that reduced quantities of glycine observed in obese subjects likely results from an upregulation of the hepatic glycine cleavage system and that dietary glycine supplementation potentially reduces obesity in ZDF rats.

Assessment of Cutaneous Melanoma by Use of Very- High-Frequency Ultrasound and Real-Time Elastography.

OBJECTIVE: The primary objective of this study was to evaluate the usefulness of very-high-frequency ultrasound as tool for assessment of skin melanoma by investigation of the correlation between the ultrasound measurement of the thickness of a melanoma and the histopathologically measured Breslow index. The secondary objective was to assess the potential role of real-time elastography in the preoperative evaluation of skin melanoma. SUBJECTS AND METHODS: The study included 42 cutaneous melanoma lesions in 39 adult subjects examined in the division of ultrasound of a department of radiology between September 2011 and January 2015. Gray-scale sonographic features at 40 MHz (thickness, echogenicity, contour) and real-time strain elastographic (qualitative and semiquantitative, strain ratio) characteristics were evaluated and compared with the pathologic results. RESULTS: The melanoma lesions had a homogeneous hypoechoic appearance with a regular contour and stiff or medium consistency. The mean difference between Breslow index and ultrasound thickness was -0.05 mm (95% CI, -0.24 to 0.13 mm), sustaining the absence of significant differences between these two measurements. A strong relation was identified between real-time elastographic appearance and strain ratio for the relations between lesion and hypodermis and between lesion and neighboring dermis (p < 0.002) or hypodermis. CONCLUSION: Our study showed that very-high-frequency ultrasound and real-time elastography can be useful examinations for comprehensive preoperative evaluation of cutaneous melanoma.

Diffuse angiomatosis of the breast--sonographic appearance.

Angiomatosis or diffuse hemangioma is a very rare benign vascular tumor, consisting of blood and lymphatic channels growing diffusely in the breast parenchyma. We report a case of diffuse breast angiomatosis in a 34-year-old woman with pubertal anisomastia. Ultrasound raised the suspicion of vascular tumor, by showing large cystic spaces separated by septae with moderate blood flow, similar to those found in cystic lymphangioma. We discuss the imaging (mammography, ultrasound, and MRI) and pathologic findings, with a brief review of the literature.

The ultrasonographic diagnosis of lymph node varicose veins in the groin - an overlooked missing link in chronic venous disease?

AIM: Chronic venous disease is a common pathology characterized by valvular incompetence and venous hypertension. The venous network of the lymph nodes at the Scarpa triangle connects the superficial and the deep venous systems. This study aimed to describe infrainguinal intranodal venous dilatations and to evaluate the connection with peripheral venous disease. MATERIAL AND METHODS: The study included 183 subjects (116 women, 67 men) who underwent Doppler ultrasound examinations of the venous system of the inferior limb in the context of chronic venous disease. The diagnosis of lymph node varices was based on well-defined criteria and the severity of the lymph node varices was established using an original classification. RESULTS: There was a statistically significant, moderately strong association, between the presence of intranodal varices and the great saphenous vein reflux (φ=0.341, p=0.000). There was a moderate-to-high positive correlation between intranodal varices and the chronic venous disease stage (rrb=0.457, p=0.000). CONCLUSIONS: Patients with more advanced stages of chronic venous insufficiency have a higher probability of presenting intranodal varices. Lymph node venous network identification could considerably impact clinical decision-making and treatment choices.

Income inequality, social cohesion, and crime against businesses: Evidence from a global sample of firms.

Rising inequality is one of the grand societal challenges of our time. Yet, its effects on firms - including multinational enterprises (MNEs) - and their operations have not been widely examined by IB scholars. In this study, we posit that income inequality within a country is positively associated with the incidence and severity of crime experienced by businesses. Further, we propose that this relationship will be negatively moderated by social cohesion (in the form of greater societal trust and lower ethno-linguistic fractionalization) in these countries, such that social cohesion helps to offset the negative impacts of inequality on crime against businesses. We test these hypotheses using a comprehensive data set of 114,000 firms from 122 countries and find consistent support for our theses. Our findings, which are robust to different alternative variables, model specifications, instrumentation, and estimation techniques, unpack the intricate ways through which inequality affects businesses worldwide and the associated challenges to MNEs. They also offer important managerial and policy insights regarding the consequences of inequality and potential mitigation mechanisms. Supplementary Information: The online version contains supplementary material available at 10.1057/s41267-022-00535-5.

L'inégalité croissante est l'un des grands défis sociétaux de notre époque. Pourtant, ses impacts sur les entreprises - y compris les entreprises multinationales - et leurs activités n'ont pas été largement examinés par les chercheurs en affaires internationales. Dans cette recherche, nous postulons que l'inégalité des revenus dans un pays est positivement associée à l'incidence et à la gravité de la criminalité subies par les entreprises. De plus, nous proposons que cette relation soit négativement modérée par la cohésion sociale dans ces pays (sous la forme d'une plus grande confiance sociétale et d'une plus faible fragmentation ethnolinguistique), dans la mesure où la cohésion sociale aide à compenser les impacts négatifs de l'inégalité sur la criminalité contre les entreprises. Nous testons ces hypothèses sur un ensemble complet de données de 114000 entreprises issues de 122 pays et trouvons des appuis cohérents à nos thèses. Nos résultats, robustes aux différentes variables alternatives, spécifications du modèle, techniques d'estimation et à l'instrumentation, dévoilent les manières complexes par lesquelles l'inégalité influe sur les entreprises dans le monde entier ainsi que sur les défis associés aux entreprises multinationales. Ils apportent également d'importants renseignements managérial et politique liés aux conséquences de l'inégalité et aux mécanismes d'atténuation potentiels.

El aumento de la desigualdad es uno de los grandes desafíos sociales de nuestro tiempo. Con todo, sus efectos en las empresas, incluyendo las empresas multinacionales, y sus operaciones no han sido ampliamente examinado por académicos de Negocios Internacionales. En este estudio, planteamos que la desigualdad en un país está asociada positivamente con la incidencia y gravedad de la delincuencia que experimentan las empresas. Aún más, proponemos que esta relación será moderada negativamente por la cohesión social (en forma de mayor confianza social y menor fraccionamiento etnolingüístico) en estos países, para que la cohesión social ayuda a compensar los impactos negativos de la desigualdad en la delincuencia contra las empresas. Probamos estas hipótesis utilizando un exhaustivo conjunto de datos de 114.000 empresas de 122 países y encontramos un apoyo consistente a nuestras tesis. Nuestros hallazgos, que son robustos a diferentes variables alternativas, especificaciones del modelo, instrumentación y técnicas de estimación, desentrañan las maneras intrincadas en que la desigualdad afecta a las empresas de todo el mundo y los desafíos asociados a las empresas multinacionales. También ofrecen importantes perspectivas para la gerencia y política en relación con las consecuencias de la desigualdad y los posibles mecanismos de mitigación.

O aumento da desigualdade é um dos grandes desafios sociais do nosso tempo. No entanto, seus efeitos sobre empresas ­ incluindo empresas multinacionais (MNEs) ­ e suas operações não foram amplamente examinados por acadêmicos de IB. Neste estudo, postulamos que a desigualdade de renda dentro de um país é positivamente associada à incidência e gravidade de crimes vivenciados por empresas. Além disso, propomos que essa relação seja negativamente moderada pela coesão social (na forma de maior confiança social e menor fracionamento etnolinguístico) nesses países, de modo que a coesão social ajude a compensar os impactos negativos da desigualdade em crimes contra empresas. Testamos essas hipóteses usando um conjunto de dados abrangente de 114.000 empresas de 122 países e encontramos consistente suporte para nossas teses. Nossos achados, robustos a diferentes variáveis alternativas, especificações de modelo, instrumentação e técnicas de estimação, desvendam as formas intrincadas pelas quais a desigualdade afeta negócios em todo o mundo e os desafios associados a MNEs. Eles também oferecem importantes insights gerenciais e de políticas no que tange às consequências da desigualdade bem como potenciais mecanismos mitigantes.

Spatial Stress and Strain Distributions of Viscoelastic Layers in Oscillatory Shear.

One of the standard experimental probes of a viscoelastic material is to measure the response of a layer trapped between parallel surfaces, imposing either periodic stress or strain at one boundary and measuring the other. The relative phase between stress and strain yields solid-like and liquid-like properties, called the storage and loss moduli, respectively, which are then captured over a range of imposed frequencies. Rarely are the full spatial distributions of shear and normal stresses considered, primarily because they cannot be measured except at boundaries and the information was not deemed of particular interest in theoretical studies. Likewise, strain distributions throughout the layer were traditionally ignored except in a classical protocol of Ferry, Adler and Sawyer, based on snapshots of standing shear waves. Recent investigations of thin lung mucus layers exposed to oscillatory stress (breathing) and strain (coordinated cilia), however, suggest that the wide range of healthy conditions and environmental or disease assaults lead to conditions that are quite disparate from the "surface loading" and "gap loading" conditions that characterize classical rheometers. In this article, we extend our previous linear and nonlinear models of boundary stresses in controlled oscillatory strain to the entire layer. To illustrate non-intuitive heterogeneous responses, we characterize experimental conditions and material parameter ranges where the maximum stresses migrate into the channel interior.

Inhibition of HIV-1 virion production by a transdominant mutant of integrase interactor 1.

Integase interactor 1 (INI1), also known as hSNF5, is a protein that interacts with HIV-1 integrase. We report here that a cytoplasmically localized fragment of INI1 (S6; aa183-294) containing the minimal integrase-interaction domain potently inhibits HIV-1 particle production and replication. Mutations in S6 or integrase that disrupt integrase-INI1 interaction abrogated the inhibitory effect. An integrase-deficient HIV-1 transcomplemented with integrase fused to Vpr was not affected by S6. INI1 was specifically incorporated into virions and was required for efficient HIV-1 particle production. These results indicate that INI1 is required for late events in the viral life cycle, and that ectopic expression of S6 inhibits HIV-1 replication in a transdominant manner via its specific interaction with integrase within the context of Gag-Pol, providing a novel strategy to control HIV-1 replication.

Contrast-Enhanced Ultrasonography in the Diagnosis and Treatment Modulation of Breast Cancer.

The aim of this paper is to highlight the role of contrast-enhanced ultrasound in breast cancer in terms of diagnosis, staging and follow-up of the post-treatment response. Contrast-enhanced ultrasound (CEUS) is successfully used to diagnose multiple pathologies and has also clinical relevance in breast cancer. CEUS has high accuracy in differentiating benign from malignant lesions by analyzing the enhancement characteristics and calculating the time-intensity curve's quantitative parameters. It also has a significant role in axillary staging, especially when the lymph nodes are not suspicious on clinical examination and have a normal appearance on gray-scale ultrasound. The most significant clinical impact consists of predicting the response to neoadjuvant chemotherapy, which offers the possibility of adjusting the therapy by dynamically evaluating the patient. CEUS is a high-performance, feasible, non-irradiating, accessible, easy-to-implement imaging method and has proven to be a valuable addition to breast ultrasound.

A framework to predict the price of energy for the end-users with applications to monetary and energy policies.

Energy affects every single individual and entity in the world. Therefore, it is crucial to precisely quantify the "price of energy" and study how it evolves through time, through major political and social events, and through changes in energy and monetary policies. Here, we develop a predictive framework, an index to calculate the average price of energy in the United States. The complex energy landscape is thoroughly analysed to accurately determine the two key factors of this framework: the total demand of the energy products directed to the end-use sectors, and the corresponding price of each product. A rolling horizon predictive methodology is introduced to estimate future energy demands, with excellent predictive capability, shown over a period of 174 months. The effectiveness of the framework is demonstrated by addressing two policy questions of significant public interest.

Ultrasonography and SARS-CoV 2 infection: a review of what we know and do not yet know.

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Maternal arginine supplementation enhances thermogenesis in the newborn lamb.

Body temperature maintenance is one of the most important physiological processes initiated after birth. Brown adipose tissue (BAT) is an essential mediator of thermogenesis in many species and is responsible for 50% of the heat generated in the newborn lamb. To determine if maternal arginine supplementation could enhance thermogenesis in the neonate, we randomly assigned 31 multiparous Suffolk ewes, gestating singletons or twins, to receive intravenous injections of either l-arginine (27 mg/kg body weight; n = 17) or sterile saline (n = 14) three times daily from day 75 to 125 of gestation (term = 147). Following parturition, lambs were removed from their mothers and subjected to 0 °C cold challenges at 4 and 22 h of age. Rectal temperatures were higher for the duration of the cold challenges in lambs from arginine-treated ewes compared with lambs from saline-treated ewes (P < 0.05). Elevated rectal temperatures were associated with increased (P < 0.05) circulating glycine and serine concentrations in lambs. The mRNA expression of genes related to BAT function changed over time, but not between lambs from arginine-treated vs. saline-treated ewes. Results indicate that maternal arginine treatment increases neonatal thermogenesis after birth. Although the underlying mechanisms remain to be elucidated, these data are a first step in improving neonatal survival in response to cold.

Adaptive responses to maternal nutrient restriction alter placental transport in ewes.

INTRODUCTION: Maternal nutrient partitioning, uteroplacental blood flow, transporter activity, and fetoplacental metabolism mediate nutrient delivery to the fetus. Inadequate availability or delivery of nutrients results in intrauterine growth restriction (IUGR), a leading cause of neonatal morbidity and mortality. Maternal nutrient restriction can result in IUGR, but only in an unforeseeable subset of individuals. METHODS: To elucidate potential mechanisms regulating fetal nutrient availability, singleton sheep pregnancies were generated by embryo transfer. Pregnant ewes received either a 50% NRC (NR; n = 24) or 100% NRC (n = 7) diet from gestational Day 35 until necropsy on Day 125. Maternal weight did not correlate with fetal weight; therefore, the six heaviest (NR Non-IUGR) and five lightest (NR IUGR) fetuses from nutrient-restricted ewes, and seven 100% NRC fetuses, were compared to investigate differences in nutrient availability. RESULTS: Insulin, multiple amino acids, and their metabolites, were reduced in fetal circulation of NR IUGR compared to NR Non-IUGR and 100% NRC pregnancies. In contrast, glucose in fetal fluids was not different between groups. There was a nearly two-fold reduction in placentome volume and fetal/maternal interface length in NR IUGR compared to NR Non-IUGR and 100% NRC pregnancies. Changes in amino acid concentrations were associated with altered expression of cationic (SLC7A2, SLC7A6, and SLC7A7) and large neutral (SLC38A2) amino acid transporters in placentomes. DISCUSSION: Results establish a novel approach to study placental adaptation to maternal undernutrition in sheep and support the hypothesis that amino acids and polyamines are critical mediators of placental and fetal growth in sheep.

Proteomics of regenerated tissue in response to a titanium implant with a bioactive surface in a rat tibial defect model.

Due to their excellent mechanical and biocompatibility properties, titanium-based implants are successfully used as biomedical devices. However, when new bone formation fails for different reasons, impaired fracture healing becomes a clinical problem and affects the patient's quality of life. We aimed to design a new bioactive surface of titanium implants with a synergetic PEG biopolymer-based composition for gradual delivery of growth factors (FGF2, VEGF, and BMP4) during bone healing. The optimal architecture of non-cytotoxic polymeric coatings deposited by dip coating under controlled parameters was assessed both in cultured cells and in a rat tibial defect model (100% viability). Notably, the titanium adsorbed polymer matrix induced an improved healing process when compared with the individual action of each biomolecules. High-performance mass spectrometry analysis demonstrated that recovery after a traumatic event is governed by specific differentially regulated proteins, acting in a coordinated response to the external stimulus. Predicted protein interactions shown by STRING analysis were well organized in hub-based networks related with response to chemical, wound healing and response to stress pathways. The proposed functional polymer coatings of the titanium implants demonstrated the significant improvement of bone healing process after injury.

Cardiovascular magnetic resonance: contribution to the exploration of cardiomyopathies.

BACKGROUND AND AIMS: Magnetic resonance imaging is a non-invasive and non-irradiating imaging method, complementary to cardiac ultrasound in the assessment of cardiovascular disease and implicitly of cardiomyopathies. Although it is not a first intention imaging method, it is superior in the assessment of cardiac volumes, left ventricular ejection fraction, in the analysis of cardiac wall dyskinesia and myocardial tissue characteristics with and without using a contrast agent. The purpose of this paper is to review the current knowledge regarding cardiovascular magnetic resonance imaging (CMR) and its applications in cardiomyopathy analysis. METHODS: In order to create this review, relevant articles were searched and analyzed by using MeSH terms such as: "cardiac magnetic resonance imaging", "cardiomyopathy", "myocardial fibrosis". Three main international databases PubMed, Web of Science and Medscape were searched. We carried out a narrative review focused on the current indications of cardiovascular magnetic resonance imaging in cardiomyopathies, both common and raret, of ischemic and nonischemic types. RESULTS: Cardiac magnetic resonance imaging has a very important role in the diagnosis, assessment and prognosis of common cardiomyopathies (the dilated, hypertrophic and inflammatory types) or other more rare ones such as (amyloidosis, arrhythmogenic right ventricular, non-compaction or Takotsubo cardiomyopathy), as it represents the gold standard for evaluating the ejection fraction, ventricular volumes and mass. CMR techniques, such as late gadolinium enhancement, T1 and T2 mapping have proven their usefulness, helping differentiate between ischemic (subendocardial enhancement) and nonischemic cardiomyopathy (varied pattern) or also establish the etiology. Another important feature of this imaging technique is that it can establish the myocardial viability, thus the chance of contractile recovery after revascularization. This feature is based on the transmural extent of LGE, left ventricle wall thickness and the assessment of the contractile reserve after administration of low dose dobutamine. CONCLUSIONS: Cardiovascular magnetic resonance imaging is an indispensable tool, with proven efficiency, capable of providing the differential diagnosis between ischemic and nonischemic cardiomyopathy or establishing the etiology in the nonischemic type. In addition, these findings have a prognostic value, they may guide the patient management plan and, if necessary, can evaluate treatment response. Therefore, this technique should be part of any routine investigation of various cardiomyopathies.

Extensions of the Ferry shear wave model for active linear and nonlinear microrheology.

The classical oscillatory shear wave model of Ferry et al. [J. Polym. Sci. 2:593-611, (1947)] is extended for active linear and nonlinear microrheology. In the Ferry protocol, oscillation and attenuation lengths of the shear wave measured from strobe photographs determine storage and loss moduli at each frequency of plate oscillation. The microliter volumes typical in biology require modifications of experimental method and theory. Microbead tracking replaces strobe photographs. Reflection from the top boundary yields counterpropagating modes which are modeled here for linear and nonlinear viscoelastic constitutive laws. Furthermore, bulk imposed strain is easily controlled, and we explore the onset of normal stress generation and shear thinning using nonlinear viscoelastic models. For this paper, we present the theory, exact linear and nonlinear solutions where possible, and simulation tools more generally. We then illustrate errors in inverse characterization by application of the Ferry formulas, due to both suppression of wave reflection and nonlinearity, even if there were no experimental error. This shear wave method presents an active and nonlinear analog of the two-point microrheology of Crocker et al. [Phys. Rev. Lett. 85: 888 - 891 (2000)]. Nonlocal (spatially extended) deformations and stresses are propagated through a small volume sample, on wavelengths long relative to bead size. The setup is ideal for exploration of nonlinear threshold behavior.

Metachronal wave formation in a model of pulmonary cilia.

A three-dimensional simulation of the formation of metachronal waves in rows of pulmonary cilia is presented. The cilia move in a two-layer fluid model. The fluid layer adjacent to the cilia bases is purely viscous while the tips of the cilia move through a viscoelastic fluid. An overlapping fixed-moving grid formulation is employed to capture the effect of the cilia on the surrounding fluid. In contrast with immersed boundary methods, this technique allows a natural enforcement of boundary conditions without the need for smoothing of singular force distributions. The fluid domains are discretized using a finite volume method. The 9 + 2 internal microtubule structure of an individual cilium is modeled using large-deflection, curved, finite-element beams. The microtubule skeleton is cross-linked to itself and to the cilium membrane through spring elements which model nexin links. The cilium membrane itself is considered to be elastic and subject to fluid stresses computed from the moving grid formulation as well as internal forces transmitted from the microtubule skeleton. A cilium is set into motion by the action of dynein molecules exerting forces between adjacent microtubules. Realistic models of the forces exerted by dynein molecules are extracted from measurements of observed cilia shapes.

[Doppler ultrasound assessment of intraocular and orbital tumors]. / Ultrasonografia Doppler în patologia tumorala oculo-orbitala.

PURPOSE: To assess the role of spectral and color Doppler ultrasonography in the positive and differential diagnosis of ocular and orbital tumoral masses. MATERIAL AND METHODS: Retrospective clinical study of 153 patients with 163 ocular or / and orbital masses who were examined by spectral and color Doppler ultrasonography in the Clinic of Radiology, Cluj County Emergency Hospital, between 1997 and 2004. In all patients, the arterial impedance indices were measured by pulsed Doppler examination. The color Doppler characterization of the mass consisted in the description of intratumoral vascularity: presence, vessel number and appearance and peculiar aspects. The final diagnosis was established by histopathology in 123 tumors. In 40 tumors, the diagnosis was established by correlating the clinical findings with the results of other imaging modalities. RESULTS: The study identifies and describes peculiar ultrasonographic aspects of the vascularity in various intraocular and orbital tumors. It describes and illustrates the Doppler ultrasonographic appearance of choroidal melanoma, retinoblastoma, eyeball metastases, hemangioma, lymphangioma, optic nerve sheath glioma, inflammatory pseudotumors and tumors invading the orbit. CONCLUSIONS: The association of vascular information to the two-dimensional ultrasonographic image allows for an improved characterization of ocular and orbital tumoral masses.