779 resultados para LENS SUBLUXATION


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α-Crystallins, initially described as the major structural proteins of the lens, belong to the small heat shock protein family. Apart from their function as chaperones, α-crystallins are involved in the regulation of intracellular apoptotic signals. αA- and αB-crystallins have been shown to interfere with the mitochondrial apoptotic pathway triggering Bax pro-apoptotic activity and downstream activation of effector caspases. Differential regulation of α-crystallins has been observed in several eye diseases such as age-related macular degeneration and stress-induced and inherited retinal degenerations. Although the function of α-crystallins in healthy and diseased retina remains poorly understood, their altered expression in pathological conditions argue in favor of a role in cellular defensive response. In the Rpe65(-/-) mouse model of Leber's congenital amaurosis, we previously observed decreased expression of αA- and αB-crystallins during disease progression, which was correlated with Bax pro-death activity and photoreceptor apoptosis. In the present study, we demonstrated that α-crystallins interacted with pro-apoptotic Bax and displayed cytoprotective action against Bax-triggered apoptosis, as assessed by TUNEL and caspase assays. We further observed in staurosporine-treated photoreceptor-like 661W cells stably overexpressing αA- or αB-crystallin that Bax-dependent apoptosis and caspase activation were inhibited. Finally, we reported that the C-terminal extension domain of αA-crystallin was sufficient to provide protection against Bax-triggered apoptosis. Altogether, these data suggest that α-crystallins interfere with Bax-induced apoptosis in several cell types, including the cone-derived 661W cells. They further suggest that αA-crystallin-derived peptides might be sufficient to promote cytoprotective action in response to apoptotic cell death.

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The field of mobility studies examines social phenomena through the lens of movement. In this perspective, societies are regarded as being constantly reconfigured as they are shaped by a series of mobile entities (capital, people, information). This book engages critically with many of the claims and challenges of mobility studies by providing empirically rich reports of mobilities and their limitations. Instead of assuming a seamless world of flows, the volume foregrounds questions of power, inequality, and moorings as integral to the movement of capital, goods, images, practices, or people. It brings together the work of several internationally renowned scholars, who engage with these movements at critical sites. This is the first book to provide a critical and interdisciplinary view of mobilities covering a broad range of issues rather than a single domain. The chapters deal with current and important issues, such as organ transplants, illegal migrations, urban globalization, international policies of higher education institutions, and scientific diasporas. As a whole, the book provides new insights into how power relations shape mobilities and societies.

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Els resultats de l'estudi arqueobotànic realitzat sobre diferents àmbits de l'assentament de Sant Jaume aporta noves dades al coneixement de la gestió dels recursos vegetals de la protohistòria del nordest peninsular. El registre arqueològic constata una certa homogeneïtzació en la funcionalitat dels àmbits, que s'interpreten com a magatzems en el pis superior i espais d'estabulació a l'inferior. L'àmbit millor representat és l'A4, que conserva com a fet singular un elevat nombre de restes de llavors i fruits amb molt bon estat de conservació. Els tàxons conreats més importants són la pisana (Triticum dicoccum) i les guixes i guixols (Lathyrus sativus i Lathyrus cicera), seguits d¿una menor proporció d'ordi vestit (Hordeum vulgare), blat nu (comú/dur) (Triticum aestivum/durum), pèsol (Pisum sativum), llentia (Lens culinaris) i erb (Vicia ervilia). D'altra banda, el registre arqueobotànic del pis inferior de l'àmbit A4 sembla posar en evidència la presència de l¿associació de pisana i guixa, destinada a l'alim.

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Deficiency of carbohydrate sulfotransferase 3 (CHST3; also known as chondroitin-6-sulfotransferase) has been reported in a single kindred so far and in association with a phenotype of severe chondrodysplasia with progressive spinal involvement. We report eight CHST3 mutations in six unrelated individuals who presented at birth with congenital joint dislocations. These patients had been given a diagnosis of either Larsen syndrome (three individuals) or humero-spinal dysostosis (three individuals), and their clinical features included congenital dislocation of the knees, elbow joint dysplasia with subluxation and limited extension, hip dysplasia or dislocation, clubfoot, short stature, and kyphoscoliosis developing in late childhood. Analysis of chondroitin sulfate proteoglycans in dermal fibroblasts showed markedly decreased 6-O-sulfation but enhanced 4-O-sulfation, confirming functional impairment of CHST3 and distinguishing them from diastrophic dysplasia sulphate transporter (DTDST)-deficient cells. These observations provide a molecular basis for recessive Larsen syndrome and indicate that recessive Larsen syndrome, humero-spinal dysostosis, and spondyloepiphyseal dysplasia Omani type form a phenotypic spectrum.

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The control of whitefly Bemisia tabaci (Gennadius) biotype B (Hemiptera: Aleyrodidae) on okra (Abelmoschus esculentus L.) consists primarily in the use of insecticides, due to the lack of information on other mortality factors. The objective of this study was to evaluate the spatial and temporal population dynamics of the whitefly B. tabaci biotype B on two successive A. esculentus var. "Santa Cruz" plantations. Leaf chemical composition, leaf nitrogen and potassium contents, trichome density, canopy height, plant age, predators, parasitoids, total rainfall and median temperature were evaluated and their relationships with whitefly on okra were determined. Monthly number estimates of whitefly adults, nymphs (visual inspection) and eggs (magnifying lens) occurred on bottom, middle and apical parts of 30 plants/plantation (one leaf/plant). Plants senescence and natural enemies, mainly Encarsia sp., Chrysoperla spp. and Coccinellidae, were some of the factors that most contributed to whitefly reduction. The second okra plantation, 50 m apart from the first, was strongly attacked by whitefly, probably because of the insect migration from the first to the second plantation. No significant effects of the plant canopy on whitefly eggs and adults distribution were found. A higher number of whitefly nymphs was found on the medium part than on the bottom part.

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Kale Brassica oleracea var. acephala is attacked by whitefly Bemisia tabaci, aphid Brevicoryne brassicae and Thrips tabaci. One of the main reasons for extensive insecticide application is the lack of information about factors that control insect population. The objectives of this study were to investigate the relationships between predators and parasitoids, organic compound leaves, levels of leaf nitrogen and potassium, total rainfall, relative humidity, sunlight and median temperature on the abundance of whitefly, aphid, and thrips in kale genotype "Talo Roxo". The beating tray method, direct counting and magnifying lens were used to estimate the number of these pests, predators and parasitoids. Median temperature, sunlight and relative humidity correlated to the amount of leaf nonacosane, which in turn was associated with aphids population increase. A tendency in the reduction of aphids and thrips populations with increase in total rainfall was observed. The whitefly can be a harmful pest in kale producing regions of higher temperature and smaller rainfall. In regions which present moderate temperature, where there is a high incidence of aphids, genotype with low leaf wax content should be chosen. Natural enemies, especially the parasitoid Adialytus spp., can control agents of the aphids population in kale.

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BACKGROUND: Eotaxin-1 (CCL11) is a potent eosinophil chemotactic and activating peptide that may be implicated in the pathogenesis of chronic allergic eye disease and has been associated with the wearing of contact lenses (CL) in patients with contact lens papillary conjunctivitis (CLPC). The purpose of this study was to study eotaxin-1 expression in the tears of long-term CL wearers. PATIENTS AND METHODS: Tears were collected with glass capillaries from 15 patients (2 male, 13 female) with various degree of CLPC at 2-year intervals. CLPC severity was graded from 0 to 4 with reference to standard slit-lamp photographs of the superior tarsal conjunctiva. The eotaxin-1 level in the tears was measured by an ELISA, using mouse anti-human eotaxin monoclonal antibodies. RESULTS: The mean age was 32.5 ± 13.3 years (range: 17 - 69 years). The mean interval between the tear collections was 30 ± 4.8 months. The mean concentration of eotaxin was 2150 ± 477 pg/mL and 2486 ± 810 pg/mL for the first and second series, respectively. The difference was not statistically significant (paired Wilcoxon/Kruskal-Wallis, p = 0.803). The mean score of papilla grade was 1.26 ± 0.18 for the first sample and 1.40 ± 0.19 two years later. There was no significant difference of grading between the two time periods (paired Wilcoxon/Kruskal-Wallis, p = 0.751). CONCLUSIONS: the eotaxin-1 level remains up-regulated over a long time period in patients wearing CL, most of them with chronic CLPC. Eotaxin may play a role in the pathogenesis of contact lens intolerance.

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Cataract surgery is a common ocular surgical procedure consisting in the implantation of an artificial intraocular lens (IOL) to replace the ageing, dystrophic or damaged natural one. The management of postoperative ocular inflammation is a major challenge especially in the context of pre-existing uveitis. The association of the implanted IOL with a drug delivery system (DDS) allows the prolonged intraocular release of anti-inflammatory agents after surgery. Thus IOL-DDS represents an "all in one" strategy that simultaneously addresses both cataract and inflammation issues. Polymeric DDS loaded with two model anti-inflammatory drugs (triamcinolone acetonide (TA) and cyclosporine A (CsA)) were manufactured in a novel way and tested regarding their efficiency for the management of intraocular inflammation during the 3 months following surgery. The study involved an experimentally induced uveitis in rabbits. Experimental results showed that medicated DDS efficiently reduced ocular inflammation (decrease of protein concentration in aqueous humour, inflammatory cells in aqueous humour and clinical score). Additionally, more than 60% of the loading dose remained in the DDS at the end of the experiment, suggesting that the system could potentially cover longer inflammatory episodes. Thus, IOL-DDS were demonstrated to inhibit intraocular inflammation for at least 3 months after cataract surgery, representing a potential novel approach to cataract surgery in eyes with pre-existing uveitis.

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Wars are often associated with a rhetoric of renewal or new beginnings. This essay explores this claim through the lens of civil religion and a recent book by Carolyn Marvin and David Ingle, Blood Sacrifice and the Nation, which combines Emile Durkheim with Réné Girard in proposing that modern national cohesion depends on blood sacrifice. I unpack some of the paradoxes raised by this theory of national renewal in the context of 9/11, with a special focus on the sacred status of the flag and the special attention given to uniformed serviceman in the American body politic.

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The estimation of muscle forces in musculoskeletal shoulder models is still controversial. Two different methods are widely used to solve the indeterminacy of the system: electromyography (EMG)-based methods and stress-based methods. The goal of this work was to evaluate the influence of these two methods on the prediction of muscle forces, glenohumeral load and joint stability after total shoulder arthroplasty. An EMG-based and a stress-based method were implemented into the same musculoskeletal shoulder model. The model replicated the glenohumeral joint after total shoulder arthroplasty. It contained the scapula, the humerus, the joint prosthesis, the rotator cuff muscles supraspinatus, subscapularis and infraspinatus and the middle, anterior and posterior deltoid muscles. A movement of abduction was simulated in the plane of the scapula. The EMG-based method replicated muscular activity of experimentally measured EMG. The stress-based method minimised a cost function based on muscle stresses. We compared muscle forces, joint reaction force, articular contact pressure and translation of the humeral head. The stress-based method predicted a lower force of the rotator cuff muscles. This was partly counter-balanced by a higher force of the middle part of the deltoid muscle. As a consequence, the stress-based method predicted a lower joint load (16% reduced) and a higher superior-inferior translation of the humeral head (increased by 1.2 mm). The EMG-based method has the advantage of replicating the observed cocontraction of stabilising muscles of the rotator cuff. This method is, however, limited to available EMG measurements. The stress-based method has thus an advantage of flexibility, but may overestimate glenohumeral subluxation.

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PURPOSE: To evaluate the safety and efficacy of an intravitreal fluocinolone acetonide (FA) implant compared with standard therapy in subjects with noninfectious posterior uveitis (NIPU). DESIGN: Randomized, controlled, phase 2b/3, open-label, multicenter superiority trial. PARTICIPANTS: Subjects with unilateral or bilateral NIPU. METHODS: One hundred forty subjects received either a 0.59-mg FA intravitreal implant (n = 66) or standard of care (SOC; n = 74) with either systemic prednisolone or equivalent corticosteroid as monotherapy (> or =0.2 mg/kg daily) or, if judged necessary by the investigator, combination therapy with an immunosuppressive agent plus a lower dose of prednisolone or equivalent corticosteroid (> or =0.1 mg/kg daily). MAIN OUTCOME MEASURES: Time to first recurrence of uveitis. RESULTS: Eyes that received the FA intravitreal implant experienced delayed onset of observed recurrence of uveitis (P<0.01) and a lower rate of recurrence of uveitis (18.2% vs. 63.5%; P< or =0.01) compared with SOC study eyes. Adverse events frequently observed in implanted eyes included elevated intraocular pressure (IOP) requiring IOP-lowering surgery (occurring in 21.2% of implanted eyes) and cataracts requiring extraction (occurring in 87.8% of phakic implanted eyes). No treatment-related nonocular adverse events were observed in the implant group, whereas such events occurred in 25.7% of subjects in the SOC group. CONCLUSIONS: The FA intravitreal implant provided better control of inflammation in patients with uveitis compared with systemic therapy. Intraocular pressure and lens clarity of implanted eyes need close monitoring in patients receiving the FA intravitreal implant.

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OBJECTIVES: To describe the spectrum of pathologies responsible for neck ailments in a primary care pediatric emergency setting and evaluate their outcome. METHODS: All children aged 16 years or younger, who presented to the emergency department of the Children's Hospital of Lausanne during a 1-year period, were retrospectively identified and charts were reviewed. Causes of neck complaints were classified as traumatic (group 1), infectious (group 2), postural (group 3), or miscellaneous (group 4) according to the final diagnosis. History and physical examination findings, radiological and laboratory results, as well as patient outcomes were recorded. RESULTS: During the study period, 28,722 children were observed in the emergency department, and 170 were identified as having neck complaints. The number of patients with neck ailments in group 1 was 105 (62%). Group 2 contained 33 patients (19%), of which 28 (16.5%) had a viral infection and 5 (2.9%) had a bacterial infection. Group 3 contained 30 children (17.6%) and group 4 contained 2 children (1.2%). Cervical spine radiography was performed on an emergency basis in 60 children (57 in group 1, 2 in group 2, and 1 in group 3). Significant abnormalities were observed in 6 children. Cervical computed tomography (CT) was performed in 9 children, from which 5 were in group 1, 3 were in group 2, and 1 was in group 4. The CT scan revealed pathologic findings in 6 children. Follow-up data were available in 135 patients (79.4%), of which 129 (95.6%) experienced complete recovery in less than 2 weeks. Admission to the hospital was necessary in 4 children (1 in group 1 and 3 in group 2), including 2 for emergency surgical drainage of retropharyngeal abscesses. One child with posttraumatic torticollis was treated conservatively as an outpatient and recovered in 7 weeks. One child was had his/her condition eventually diagnosed with osteoid osteoma and treated with oral nonsteroidal anti-inflammatory drug. CONCLUSIONS: Most cases of neck ailments in children presenting to the emergency department were due to trauma or infection, which were effectively managed as outpatients. When signs and symptoms suggested an emergent cause, CT provided a definitive diagnosis. The evaluation of a child presenting with acute neck complaints should be based on history and physical examination. Plain radiographs and CT scan are contributive in selected cases.

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The purpose of this thesis is to reveal how the laser cutting parameters influence lasercutting of particleboard, HDF and MDF. The literature review introduces the basic principle of CO2 laser, CO2 laser equipment and its usage in cutting of wood-based materials. The experimental part focuses on the discussion and analysis ofthe test data and attempts to draw conclusions on the influence of various parameters, including laser power, focal length of the lens and cutting gas, on the cutting speed and kerf quality. The tested materials include various thicknesses of particleboard, HDF and MDF samples. A TRUMPF TLF2700 HQ laser equipment was used for the experiments. To obtain valid data, the test samples must be completely cut through without any bonding of wood fibre. The maximum cutting speed is linear dependent on the laser power in thecondition that the other parameters are constant. For each thickness of a specific material type, there is a minimum laser power for cutting. Normally, the topand bottom kerf widths increase with the enhancement of laser power. There may be a critical laser power which can generate the minimum cross-sectional kerf width. Lens of larger focal length may achieve higher cutting speed. As the focal length becomes larger, the top kerf width tends to increase while the bottom andcross-sectional kerf widths to the opposite. Of all cutting gases, oxygen can help achieve higher cutting speed. The gas pressure of nitrogen does not seem to have strong influence on the cutting result. Generally, 2 bar air is more preferable for higher cutting speed. For particleboard and MDF samples of larger thickness than 12 mm, 2 bar argon can be used to reach remarkably higher cutting speed than the 5 bar. Generally, the 190.5 mm lens can produce smallest total kerf width. The kerf sides of thicker samples are darker than the thinner ones. The sample darkness tends to be lower as laser power increased. 63.5 mm lens seemed tocause more darkness than other lens. 5 bar cutting gases can produce less dark side kerfs than 2 bar ones. Oxygen normally causes darker kerfs than other gases. No distinct differences were found between nitrogen and argon.

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Due to the power of genetics, the mouse has become a widely used animal model in vision research. However, its eyeball has an axial length of only about 2 mm. The present protocol describes how to easily dissect the small rodent eye post mortem. This allows collecting different tissues of the eye, i.e., cornea, lens, iris, retina, optic nerve, retinal pigment epithelium (RPE), and sclera. We further describe in detail how to process these eye samples in order to obtain high‐quality RNA for RNA expression profiling studies. Depending on the eye tissue to be analyzed, we present appropriate lysis buffers to prepare total protein lysates for immunoblot and immuno‐precipitation analyses. Fixation, inclusion, embedding, and cryosectioning of the globe for routine histological analyses (HE staining, DAPI staining, immunohistochemistry, in situ hybridization) is further presented. These basic protocols should allow novice investigators to obtain eye tissue samples rapidly for their experiments.

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Laajojen pintojen kuvaaminen rajoitetussa työskentelytilassa riittävällä kuvatarkkuudella voi olla vaikeaa. Kuvaaminen on suoritettava osissa ja osat koottava saumattomaksi kokonaisnäkymäksi eli mosaiikkikuvaksi. Kuvauslaitetta käsin siirtelevän käyttäjän on saatava välitöntä palautetta, jotta mosaiikkiin ei jäisi aukkoja ja työ olisi nopeaa. Työn tarkoituksena oli rakentaa pieni, kannettava ja tarkka kuvauslaite paperi- ja painoteollisuuden tarpeisiin sekä kehittää palautteen antamiseen menetelmä, joka koostaaja esittää karkeaa mosaiikkikuvaa tosiajassa. Työssä rakennettiin kaksi kuvauslaitetta: ensimmäinen kuluttajille ja toinen teollisuuteen tarkoitetuista osista. Kuvamateriaali käsiteltiin tavallisella pöytätietokoneella. Videokuvien välinen liike laskettiin yksinkertaisella seurantamenetelmällä ja mosaiikkikuvaa koottiin kameroiden kuvanopeudella. Laskennallista valaistuksenkorjausta tutkittiin ja kehitetty menetelmä otettiin käyttöön. Ensimmäisessä kuvauslaitteessa on ongelmia valaistuksen ja linssivääristymien kanssa tuottaen huonolaatuisia mosaiikkikuvia. Toisessa kuvauslaitteessa nämä ongelmat on korjattu. Seurantamenetelmä toimii hyvin ottaen huomioon sen yksinkertaisuuden ja siihen ehdotetaan monia parannuksia. Työn tulokset osoittavat, että tosiaikainen mosaiikkikuvan koostaminen megapikselin kuvamateriaalista on mahdollista kuluttajille tarkoitetulla tietokonelaitteistolla.