360 resultados para Nevus, Pigmented
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We report the case of a 60-year-old man presenting bilateral progressive proptosis with diplopia, weight loss, tachycardia, nervosity, and stomach pain. These signs seemed at first to favor a diagnosis of Graves'ophthalmopathy. Thyroid tests were negative and the initial orbital CT scan was considered normal. A new radiological investigation 4 months later in our hospital revealed typical hypertrophy of the extraocular muscles compatible with orbital metastasis. The systemic investigations demonstrated a pulmonary tumor, multiple hepatic lesions, and several pigmented nodules of gastric mucosa. The pathology of pulmonary and gastric specimens confirmed the diagnosis of malignant melanoma. The primary lesion remains unknown. The authors discuss the differential diagnoses of orbital metastasis and the radiological characteristics of orbital metastasis in malignant melanoma.
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PURPOSE: To evaluate the photodynamic potential of a new hydrosoluble photosensitizer (WST-11, Stakel; Steba Biotech, Toussus-Le-Noble, France), for use in occlusion of normal choroidal vessels in the rabbit eye and CNV (choroidal neovascularization) in the rat eye. METHODS: Occlusive and nonocclusive parameters of Stakel and verteporfin photodynamic therapy (PDT) were investigated in pigmented rabbits. Eyes were followed by fluorescein angiography (FA) and histology at various intervals after PDT. RESULTS: When occlusive parameters (fluence of 50 J/cm(2), 5 mg/kg drug dose and DLI [distance to light illumination] of 1 minute) were used, Stakel PDT was efficient immediately after treatment without associated structural damage of the RPE and retina overlying the treated choroid in the rabbit eye. Two days later, total occlusion of the choriocapillaries was seen in 100% of the treated eyes, along with accompanying histologic structural changes in the overlying retina. When the occlusive parameters (fluence, 100 J/cm2; drug dose, 12 mg/m2; and DLI, 5 minutes) of verteporfin PDT were used, occlusion of the choriocapillaries was observed in 89% of the treated eyes. Histology performed immediately after treatment demonstrated structural damage of the overlying retina and RPE layer. Weaker, nonocclusive Stakel PDT parameters (25 J/cm2, 5 mg/kg, and DLI of 10 minutes) did not induce choriocapillary occlusion or retinal lesions on FA or histology. Weaker, nonocclusive verteporfin PDT parameters (10 J/cm2, 0.2 mg/kg, and DLI of 5 minutes) did not induce choriocapillary occlusion. However, histology of these eyes showed the presence of damage in the retinal and choroidal tissues. Moreover, preliminary results indicate that selective CNV occlusion can be achieved with Stakel PDT in the rat eye. CONCLUSIONS: Unlike verteporfin PDT, Stakel PDT does not cause direct damage to the RPE cell layer or retina. These observations indicate that Stakel PDT may have a high potential for beneficial therapeutic outcomes in treatment of AMD.
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PURPOSE: To evaluate the antimitotic and toxic effects of 5-chlorouracil (5-CU) and 5-fluorouracil (5-FU) and study their potential to delay filtering bleb closure in the rabbit eye when released by poly(ortho esters) (POE). METHODS: Rabbit Tenon fibroblasts and human conjunctival cells were incubated with various 5-CU and 5-FU concentrations. Antiproliferative effects and toxicity were evaluated at 24 and 72 hours by monotetrazolium, neutral red, and Hoechst tests and cell counting. Mechanisms of cell death were evaluated using TUNEL assay, annexin V binding, immunohistochemistry for anti-apoptosis-inducing factor (AIF) and LEI/L-DNase II. Trabeculectomy was performed in pigmented rabbits. Two hundred microliters of POE loaded with 1% wt/wt 5-FU or 5-CU was injected into the subconjunctival space after surgery. Intraocular pressure (IOP) and bleb persistence were monitored for 150 days. RESULTS: In vitro, 5-FU showed a higher antiproliferative effect and a more toxic effect than 5-CU. 5-FU induced cell necrosis, whereas 5-CU induced mostly apoptosis. The apoptosis induced by 5-CU was driven through a non-caspase-dependent pathway involving AIF and LEI/L-DNase II. In vivo, at 34 days after surgery, the mean IOP in the POE/5-CU-treated group was 83% of the baseline level and only 40% in the POE/5-FU-treated group. At 100 days after surgery, IOP was still decreased in the POE/5-CU group when compared with the controls and still inferior to the preoperative value. The mean long-term IOP, with all time points considered, was significantly (P < 0.0001) decreased in the POE/5-CU-treated group (6.0 +/- 2.4 mm Hg) when compared with both control groups, the trabeculectomy alone group (7.6 +/- 2.9 mm Hg), and the POE alone group (7.5 +/- 2.6 mm Hg). Histologic analysis showed evidence of functioning blebs in the POE-5-CU-treated eyes along with a preserved structure of the conjunctiva epithelium. CONCLUSIONS: The slow release of 5-CU from POE has a longstanding effect on the decrease of IOP after glaucoma-filtering surgery in the rabbit eye. Thus, the slow release of POE/5-CU may be beneficial for the prevention of bleb closure in patients who undergo complicated trabeculectomy.
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Corticosteroids are hormones involved in many physiological responses such as stress, immune modulation, protein catabolism and water homeostasis. The subfamily of glucocorticoids is used systemically in the treatment of inflammatory diseases or allergic reactions. In the eye, glucocorticoides are used to treat macular edema, inflammation and neovascularization. The most commonly used glucocorticoid is triamcinolone acetonide (TA). The pharmaceutical formulation of TA is not adapted for intravitreal administration but has been selected by ophthalmologists because its very low intraocular solubility provides sustained effect. Visual benefits of intraocular TA do not clearly correlate with morpho-anatomical improvements, suggesting potential toxicity. We therefore studied, non-common, but deleterious effects of glucocorticoids on the retina. We found that the intravitreal administration of TA is beneficial in the treatment of neovascularization because it triggers cell death of endothelial cells of neovessels by a caspase-independent mechanism. However, this treatment is toxic for the retina because it induces a non-apoptotic, caspase-independent cell death related to paraptosis, mostly in the retinal pigmented epithelium cells and the Müller cells.
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Purpose: To investigate the molecular involvement of PTEN, a tumor suppressor gene, in a case of cellular pigmented choroidal Schwannoma in a patient with hamartomatous syndrome due to heterozygous PTEN germline mutation. Methods: Histopathological, immunohistochemical, and electron microscopy analyses were performed by standard procedures. Paraffin-embedded samples of normal and tumor eye tissues were collected and DNA was extracted. A 145 bp region flanking the heterozygous c.406T>C mutation in exon 5 of PTEN was amplified by PCR and sequenced. To evaluate the allelic status of PTEN in the tumor sample, we cloned different PCR products in E. coli using a TA cloning procedure. Results: Histopathology demonstrated a posterior choroidal mass measuring 1.3 x 1.6 x 1.4 cm. The tumor was composed by fascicles of spindle cells with wavy cytoplasm. No Verrocay bodies could be identified. Scattered histiocytes with clear cytoplasm were present. By immunohistochemistry, the cells were expressing S100 and focally Melan A proteins. Pericellular type IV collagen could be demonstrated. Interlacing cytoplasmic processes covered by thick basement membrane could be found by electron microscopy as well as few premelanosomes. Moderate PTEN expression by immunohistochemistry was identified in some cells. As expected, the germline mutation could be detected by DNA sequencing in both the paraffin-embedded normal and tumor eye tissues. Analysis of 33 E. coli colonies bearing clones from the tumor eye tissue DNA surprisingly revealed that most of them contained the PTEN wild-type allele (29 vs. 4, Fisher's test p-value = 0.002). Conclusions: This is the first reported case of choroidal cellular Schwannoma arising in the context of a PTEN hamartomatous syndrome. Allelic analysis of PTEN in the tumor suggests a statistically-significant partial loss of heterozygozity in favor of the wild-type allele. Our findings are in clear contrast with what is usually observed in cancer tissues, for which mutated alleles of tumor suppressor genes are usually brought to homozygosity. Similar results were previously reported in human non-Hodgkin's lymphomas, displaying an overexpression of the wild-type form of the tumor suppressor gene p53. We are in the process of investigating additional DNA derived from other fresh and paraffin-embedded tissues from the patient, in order to gain insights on the molecular bases of PTEN involvement in this rare choroidal Schwannoma.
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Résumé La dérégulation de c-Myc est un événement fréquent de la transformation cellulaire. Une régulation positive de cette oncoprotéine a été démontrée dans divers mélanomes cutanés primaires et métastatiques et est associée à un pronostic défavorable (Grover et al., 1996; Zhuang et al., 2008). c-Myc est considéré comme une molécule centrale impliquée dans plusieurs processus de l'homéostasie cellulaire. En raison de sa contribution importante dans la progression tumorale, la fonction de c-Myc a été étudiée intensément. Cependant nous connaissons peu le rôle de ce facteur de transcription dans l'embryogenèse et dans la spécification tissulaire. Un déficit total de c-Myc pendant l'embryogenèse conduit à la mort embryonnaire avant 10.5 jours de gestation. Cette mort est causée par de multiples imperfections du développement touchant la taille de l'embryon, le coeur, le péricarde, le tube neural et les cellules sanguines (Davis et al., 1993; Trumpp et al., 2001). Récemment, il a été montré que la plupart de ces anomalies sont secondaires et résultent d'une insuffisance du placenta dans les embryons c-myc-/- (Dubois et al., 2008). Sachant que c-Myc est important dans la maintenance des lignées de la crête neurale (Wei et al., 2007), nous nous sommes intéressés au rôle de c-Myc dans le développement des cellules pigmentaires et à leur homéostasie après la naissance. Un allèle floxé de c-myc (Trumpp et al., 2001) a été utilisé pour supprimer ce gène spécifiquement dans la lignée mélanocytaire à l'aide d'une souris transgénique Tyr::Cre (Delmas et al., 2003). L'ablation des deux allèles de c-myc dans les mélanocytes des souris c-myccKO conduit au phénotype de grisonnement des poils, observé directement après la naissance et associé à une diminution du nombre de mélanocytes dans le bulbe des follicules pileux. Les cellules pigmentaires restantes expriment les marqueurs mélanogéniques (Tyr, TRP-1, Dct and MITF) et semblent être fonctionnelles puisqu'elles peuvent produire et transférer la mélanine. De plus, la capacité de prolifération des mélanocytes déficients en c-Myc dans le bulbe des follicules pileux ne semble pas être affectée chez les nouveaux-nés. Les cellules souches mélanocytaires sont présentes, mais en nombre réduit, dans le bulge des follicules pileux à la fin de la morphogenèse chez les souris c-myccKO âgées de huit jours. Ces cellules sont maintenues sans changement durant le premier cycle pileux (vérifié à l'âge de trente jours), ce qui sous-entend que la fonction de c-Myc n'est pas nécessaire pour ce processus. Ceci explique pourquoi, en supposant que des cellules souches mélanocytaires fonctionnelles sont présentes dans la peau, nous n'observons pas de dilution de couleur de la robe liée à l'âge. Cependant, la présence de ces cellules souches mélanocytaires dans la peau c-myccKO ne suffit pas à assurer une quantité normale de mélanocytes différenciés dans le bulbe des follicules pileux. Cette population de cellules pigmentaires matures est sévèrement affectée par la suppression de c-Myc, ce qui contribue amplement au phénotype de grisonnement des poils. De plus, c-Myc paraît être important pour le développement des mélanocytes. Ainsi, le nombre de mélanoblastes diminue dans les embryons c-myccKO à partir du douzième jour de gestation. A treize jours de gestation, au stade où les mélanoblastes pénètrent dans l'épiderme et prolifèrent, les mélanoblastes déficients en c-Myc ne s'adaptent pas aux signaux de prolifération et se retrouvent en nombre réduit dans l'épiderme. Finalement, nous nous sommes intéressés, au rôle de N-Myc, un homologue proche de c-Myc, dans la lignée mélanocytaire. Nos expériences ont montré que. N-Myc était superflu pour le développement et l'homéostasie des mélanocytes, une seule copie du gène c-myc étant suffisante pour maintenir une pigmentation normale de la robe des souris c-mycc-myccKO/+~N_ myccKO/KO. Cependant, le rôle essentiel de N-Myc dans la maintenance des cellules mélanocytaires précurseurs apparaît lorsque c-Myc est absent, puisque la suppression simultanée des deux Myc résulte en une perte complète de la coloration de la robe. Ceci implique la présence d'un mécanisme compensatoire entre c- et N-Myc dans la lignée mélanocytaire, avec un rôle prédominant de c-Myc. Summary Deregulation of c-Myc is known to be a common event in cellular transformation. Upregulation of this oncoprotein was shown in a variety of primary and metastatic cutaneous melanomas and has been associated with a poor prognosis (Grover et al., 1996; Zhuang et al., 2008). c-myc is seen as a central molecule involved in many aspects of cellular homeostasis. c-Myc function has been intensively studied mostly because of its significant contribution to tumour progression. However little is known on the role of this transcription factor in embryogenesis and tissue specification. Complete loss of c-Myc during embryogenesis results in embryonic death before E10.5 due to multiple developmental defects including embryonic size, heart, pericardium, neural tube and blood cells (Davis et al., 1993; Trumpp et al., 2001). Recently it was discovered that most of these abnormalities are secondary and results of placental insufficiency in c-Myc-/- embryos (Dubois et al., 2008). Here, we focused on the role of c-Myc in pigment cell development and homeostasis after birth, knowing that c-Myc is important in the maintenance of neural crest lineages (Wei et al., 2007). A floxed allele of c-Myc (Trumpp et al., 2001) was used to specifically delete this gene in the melanocyte lineage using Tyr::Cre transgenic mice (Delmas et al., 2003). Removal of both c-Myc alleles in melanocytes of c-MyccKO mouse led to the grey hair phenotype which is seen directly after birth and was associated with a decrease in the melanocyte number in the bulb of the hair follicle. The remaining population of pigment cells express melanogenic markers (Tyr, TRP-1, Dct and MITF) and seem functionally normal since they can produce and transfer melanin. Furthermore proliferation capacity of c-Myc deficient melanocytes in the bulb of hair follicle seems not to be affected in newborn animals. Melanocyte stem cells (MSCs) are present but reduced in numbers in the bulge of the hair follicle at the end of morphogenesis in 8 days old c-MyccKO mice. These cells are maintained through the first hair cycle (as verified at P30) without any further changes, suggesting that c-Myc function is not required for this process. This explains why we did not detect any agerelated coat color dilution, assuming a presence of functional MSCs in the skin. Importantly, presence of MSCs in c-MyccKO skin was not sufficient for assuring a normal number of differentiated melanocytes in the bulb of the hair follicle. This population of mature pigmented cells is severely affected upon c-myc deletion thus largely contributing to the grey hair phenotype. Moreover, c-Myc appears to be important for melanocyte development. Thus, melanoblast number is affected in c-MyccKO embryos day 12 of gestation onwards. At E13.5, when melanoblasts enter the epidermis and proliferate, c-myc deficient melanoblasts failed to adapt to proliferation signals and are therefore reduced in number in the epidermis. Finally, we addressed the role of N-Myc, a closest homologue of c-Myc, in the melanocyte lineage. In these experiments, N-Myc was dispensable for melanocyte development and homeostasis, and even one copy of the c-myc gene was sufficient to maintain normal coat color pigmentation in c-mycc-mycCKO/+ ,N-myccKO/KO mice. However the crucial role of N-Myc in maintenance of melanocyte precursor cells became apparent when c-myc is eliminated since simultaneous deletion of both Myc results in complete loss of coat color pigmentation. This suggests compensatory mechanisms between c- and N-Myc with a predominant role of c-Myc in melanocyte lineage.
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The first effective therapy for exudative macular degeneration (AMD) was Photodynamic Therapy (PDT). Diagnosis of the disease was to a large extent by fluorescein angiography (FA). Distinguishing between the leaky choroidal neovessels (CNV) associated with exudative AMD, and the polypoidal structures associated with Polypoidal Choroidal Vasculopathy (PCV) is not always easy using FA alone. The switch to Indocyanine Green angiography helped to pinpoint PCV, and thus to study the efficacy of photodynamic therapy of this particular form of retinal disease, which is more frequently encountered among pigmented individuals. The results appear to be quite promising, and in the year following treatment only a small fraction of the patients had to be retreated. Alternatively, treating PCV with repeated intravitreal VEGF blocking agents was not as successful as it was in the treatment of wet AMD. However, combining PDT-induced angio-occlusion of the polypoidal lesions with anti-vascular endothelial growth factor therapy was shown to be quite effective, and the combination of PDT with an anti-angiogenic agent as well as a steroid, in a triple therapy, was recently also shown to be a quite promising option. In the present article we review the data on PDT of PCV, including combination therapies and alternative treatments. We also report on similarities and differences between AMD and PCV.
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PURPOSE: Pharmacologic modulation of wound healing after glaucoma filtering surgery remains a major clinical challenge in ophthalmology. Poly(ortho ester) (POE) is a bioerodible and biocompatible viscous polymer potentially useful as a sustained drug delivery system that allows the frequency of intraocular injections to be reduced. The purpose of this study was to determine the efficacy of POE containing a precise amount of 5-fluorouracil (5-FU) in an experimental model of filtering surgery in the rabbit. METHODS: Trabeculectomy was performed in pigmented rabbit eyes. An ointmentlike formulation of POE containing 1% wt/wt 5-FU was injected subconjunctivally at the site of surgery, during the procedure. Intraocular pressure (IOP), bleb persistence, and ocular inflammatory reaction were monitored until postoperative day 30. Quantitative analysis of 5-FU was performed in the anterior chamber. Histologic analysis was used to assess the appearance of the filtering fistula and the polymer's biocompatibility. RESULTS: The decrease in IOP from baseline and the persistence of the filtering bleb were significantly more marked in the 5-FU-treated eyes during postoperative days 9 through 28. Corneal toxicity triggered by 5-FU was significantly lower in the group that received 5-FU in POE compared with a 5-FU tamponade. Histopathologic evaluation showed that POE was well tolerated, and no fibrosis occurred in eyes treated with POE containing 5-FU. CONCLUSIONS: In this rabbit model of trabeculectomy, the formulation based on POE and containing a precise amount of 5-FU reduced IOP and prolonged bleb persistence in a way similar to the conventional method of a 5-FU tamponade, while significantly reducing 5-FU toxicity.
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Tämän diplomityön tavoitteena oli saada perustietoa tekijöistä, jotka vaikuttavat musteen kuivumiseen erilaisilla paperipinnoilla inkjet tulostuksessa. Tavoitteena oli saada tietoa erilaisista musteista, joita käytetään yleisimmissä inkjet tulostustekniikoissa, miten paperit vaikuttavat musteen kuivumiseen ja minkälaisia menetelmiä on olemassa musteen kuivumistekijöiden määrittämiseen. Lisäksi tarkoituksena oli varmistaa, voidaanko inkjetmusteiden absorptioajan määrittämiseen käytettävää DIGAT-laitetta käyttää määrittämään ja ennustamaan erilaisten musteiden kuivumista erilaisilla paperipinnoilla sekä etsiä korrelaatioita musteen absorptioajan ja teknisten paperiominaisuuksien sekä inkjet tulostuksen laadun välillä. Kirjallisuusosassa tarkasteltiin erilaisia inkjet tulostusmenetelmiä, niissä käytettäviä musteita ja musteiden koostumuksia. Tutkittiin myös paperin ja musteen välisiä vuorovaikutuksia sekä inkjet tulostuksen laatua. Kokeellisessa osassa tutkittiin musteenabsorboitumista paperiin DIGAT-laitteen avulla. kuudella eri musteella. Paperinäytteistä määritettiin teknisiä paperiominaisuuksia sekä ominaisuuksia, jotka liittyvät inkjet tulostuksen laatuun. Inkjet tulostuksen laatua tarkasteltiin tulostamalla testikuva kolmella eri tulostimella, jotka olivat Canon Bubble Jet i950, HP DeskJet Cxi970 ja Epson Stylus C46. Havaittiin, että DIGAT-laite ei sovellu määrittämään musteen absorptioaikoja kiiltäville näytteille.Tässä tutkimuksessa näyte, jonka kiilto oli 65 %, oli liian kiiltävä mitattavaksi DIGAT-laitteella. Lisäksi absorptiomäärityksissä havaittiin, että erilaiset musteet asettuvat erilailla paperin pintaan ja että pigmenttipohjaisella musteella asettumisaika oli kaikista pisin. Musteiden absorptioajat olivat nopeimpia erikoisinkjetpaperilla ja hitaimpia päällystetyillä, tiiviillä papereilla. Musteen absorptioajan ja teknisten paperiominaisuuksien ja inkjet tulostuksen laadun välisiä korrelaatioita oli vaikea havaita. Voidaan sanoa, että tulokset olivat muste- ja printterikohtaisia. Havaittiin vain muutamia teknisiä paperiominaisuuksia, jotka korreloivat hyvin musteen absorboitumisen kanssa. Nämäolivat Gurley-Hill huokoisuus, paperin tuhka- sekä kalsiumkarbonaattipitoisuus ja K&N värinabsorptio. Myöskään inkjet tulostuksen laadun ja musteen absorption välisiä korrelaatioita ei löytynyt kuin muutama; densiteetti, mottling sekä bleeding. Tämän tutkimuksen perusteella voidaan todeta DIGAT-laitteen soveltuvan hyvin kuvaamaan inkjet tulostuksen laatuominaisuuksista densiteettia, mottlingia sekä bleedingiä. DIGAT-laitetta voidaan siis käyttää avuksi ennustettaessa kuivumisaikaa ja sen vaikutusta edellä mainittuihin ominaisuuksiin. Läpipainatusominaisuuksia DIGAT-laitteen avulla ei voida tutkia, sillä ne ovat enemmän riippuvaisia paperin neliömassasta, paksuudesta ja huokoisuudesta kuinmusteen absorptioajasta. Teknisistä paperiominaisuuksista Gurley-Hill huokoisuus, paperin tuhka-sekä CaCO3-pitoisuus ja K&N värinabsorptio kuvaavat hyvin musteen imeytymisaikaa paperiin, kun taas ominaisuudet Cobb, HST ja polaari- sekädispersiokomponentit eivät kuvaa. Näyttää siltä, että testikuva, joka on tällä hetkellä käytössä UPM Tutkimus-keskuksessa, ei sovellu suurtehotulostuksen laadun tarkkailuun. Testikuva toimii hyvin pöytätulostimilla ja perinteisillä kopiopapereilla ja inkjetpapereilla, jotka on tarkoitettu tulostettaviksi hitaasti. Tulostusnopeuden ja musteen kuivumisnopeuden välisiä ilmiöitä seei tuo esille, joten se ei sovellu kuvaamaan suurtehotulostusta.
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PURPOSE: Drug delivery to treat diseases of the posterior segment of the eye, such as choroidal neovascularization and its complications, is hampered by poor intraocular penetration and rapid elimination of the drug from the eye. The purpose of this study was to investigate the feasibility and tolerance of suprachoroidal injections of poly(ortho ester) (POE), a bioerodible and biocompatible polymer, as a biomaterial potentially useful for development of sustained drug delivery systems. METHODS: After tunnelization of the sclera, different formulations based on POE were injected (100 microL) into the suprachoroidal space of pigmented rabbits and compared with 1% sodium hyaluronate. Follow-up consisted of fundus observations, echography, fluorescein angiography, and histologic analysis over 3 weeks. RESULTS: After injection, POE spread in the suprachoroidal space at the posterior pole. It was well tolerated and progressively disappeared from the site of injection without sequelae. No bleeding or retinal detachment occurred. Echographic pictures showed that the material was present in the suprachoroidal space for 3 weeks. Angiography revealed minor pigment irregularities at the site of injection, but no retinal edema or necrosis. Histology showed that POE was well tolerated in the choroid. CONCLUSIONS: POE suprachoroidal injections, an easy, controllable, and reproducible procedure, were well tolerated in the rabbit eye. POE appears to be a promising biomaterial to deliver drugs focally to the choroid and the retina.
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Lasers in pediatric dermatology were developed as a result of the treatment of port-wine stains. Infantile hemangiomas may benefit, in some cases, from laser treatment as well as venous and lymphatic malformations. For certain pigmented lesions, as well as some hamartomas, laser treatments are a credible alternative to surgical resection. Bum scars are improved by lasers which stimulate collagen remodeling. Furthermore, hair removal of congenital and acquired hypertrichosis can relieve psychosocial discomfort and improve quality of life. The management of pain and fear of children undergoing laser treatment, using either topical or general anesthesia, remains of central importance.
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We investigated two siblings with granulomatous histiocytosis prominent in the nasal area, mimicking rhinoscleroma and Rosai-Dorfman syndrome. Genome-wide linkage analysis and whole-exome sequencing identified a homozygous frameshift deletion in SLC29A3, which encodes human equilibrative nucleoside transporter-3 (hENT3). Germline mutations in SLC29A3 have been reported in rare patients with a wide range of overlapping clinical features and inherited disorders including H syndrome, pigmented hypertrichosis with insulin-dependent diabetes, and Faisalabad histiocytosis. With the exception of insulin-dependent diabetes and mild finger and toe contractures in one sibling, the two patients with nasal granulomatous histiocytosis studied here displayed none of the many SLC29A3-associated phenotypes. This mild clinical phenotype probably results from a remarkable genetic mechanism. The SLC29A3 frameshift deletion prevents the expression of the normally coding transcripts. It instead leads to the translation, expression, and function of an otherwise noncoding, out-of-frame mRNA splice variant lacking exon 3 that is eliminated by nonsense-mediated mRNA decay (NMD) in healthy individuals. The mutated isoform differs from the wild-type hENT3 by the modification of 20 residues in exon 2 and the removal of another 28 amino acids in exon 3, which include the second transmembrane domain. As a result, this new isoform displays some functional activity. This mechanism probably accounts for the narrow and mild clinical phenotype of the patients. This study highlights the"rescue" role played by a normally noncoding mRNA splice variant of SLC29A3, uncovering a new mechanism by which frameshift mutations can be hypomorphic.
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Diplomityö tehtiin Kidex Oy:lle, joka on Kiteellä sijaitseva Martela-konsernin tytäryhtiö. Kidex Oy toimii sopimusvalmistajana Martelalle sekä muille valituille levykalusteasiakkaille, ja tuotteet ovat pääasiassa toimisto- ja keittiökalusteita. Kevättalvella 2008 yritykseen siirrettiin Nummelasta pintakäsittelyosasto, jolla on tehty petsaus- ja lakkaustöitä. Näiden lisäksi tehtaalla on pohdittu mahdollisuuksia maalaustöihin, jotta UV-telalinjan kapasiteetti saataisiin paremmin käyttöön Työssä selvitettiin, mitä muutoksia UV-kovettuvilla aineilla maalaaminen vaatii linjaan ja luotiin edellytykset maalaustoiminnan aloittamiselle. Muutokset pyrittiin pitämään niin vähäisinä kuin mahdollista. Lisäksi määritettiin maalattavien tuotteiden laadun kriteerit ja todennusmenetelmät, jotka voidaan viestiä asiakkaille väärinkäsitysten välttämiseksi. Laadun todentamista varten valmistettiin sarja koekappaleita, joista mitattiin asiakkaan kannalta tärkeimmät maalikalvon ominaisuudet. Työssä tarkasteltiin myös pintakäsittelylaitoksia koskevaa VOC-asetusta ja verrattiin liuottimien kulutusta asetuksen määrittämiin rajoihin. Puulevystä valmistettujen kalusteosien pintakäsittely UV-telalinjalla eroaa oleellisesti perinteisistä menetelmistä esimerkiksi tuotantonopeuden osalta, joka johtuu pääasiassa pinnoitekalvon hetkessä tapahtuvasta kovettumisesta UV-valon vaikutuksesta. UV-aineet ovat käytännössä täysin kiinteistä aineista koostuvia, eivätkä näin sisällä vaarallisia haihtuvia liuottimia. UV-kovettuvilla tuotteilla maalaaminen on viime vuosina runsaasti tutkittu alue, joka eroaa tietyiltä osin myös pintakäsittelystä UV-kirkaslakoilla. Pigmentoitujen kalvojen kovettuminen vaatii erilaista UV-säteilyä ja levitysmäärien seuranta on huomattavasti tarkempaa.
Resumo:
The objective of this review on the investigation of "cara inchada" in cattle (CI), pursued over the last 30 years, was to elucidate the pathogenicity of the disease and come to proper conclusions on its etiology. CI has been widely considered to be of nutritional origin, caused primarily by mineral deficiency or imbalance. However, the disease consists of a rapidly progressive periodontitis, affecting the periodontal tissues at the level of the premolars and molars during the period of tooth eruption generally starting in young calves. The disease led to great economic losses for farmers in central-western Brazil, after the occupation of new land for cattle raising in the 1960s and 1970s. The lateral enlargement of the maxillary bones of affected calves gave the disease the popular name of "cara inchada", i.e., swollen or enlarged face. The enlargement was found to be due to a chronic ossifying periostitis resulting from the purulent alveolitis of CI. Black-pigmented non-saccharolytic Bacteroides melaninogenicus, always together with Actinomyces (Corynebacterium) pyogenes, were isolated in large numbers from the periodontal lesions. B. melaninogenicus could be isolated in small numbers also from the marginal gingiva of a few healthy calves maintained on CI-free farms. "In vitro"-assays showed that streptomycin and actinomycin, as well as the supernatants of cultivates of actinomycetes from soils of CI-prone farms, applied in subinhibitory concentrations to the bacteria tested, enhanced significantly (up to 10 times) the adherence of the black-pigmented B.melaninogenicus to epithelial cells of the bovine gingiva. The antibiotics are apparently produced in large quantities by the increased number of soil actinomycetes, including the genus Streptomyces, that develop when soil microflora are modified by cultivating virgin forest or "Cerrado" (tree-savanna) for the first time for cattle grazing. The epidemiology of CI now provides strong evidence that the ingestion with the forage of such antibiotics could possibly be an important determinant factor for the onset and development of this infectious periodontitis. The antibiotic enhanced adherence of B.melaninogenicus to the sulcus-epithelium of the marginal gingiva, is thought to allow it to colonize, form a plaque and become pathogenic. There is experimental evidence that this determinant factor for the development of the periodontitis is present also in the milk of the mothers of CI-diseased calves. It has been shown that the bacteria isolated from the periodontal CI-lesions produce enzymes and endotoxins capable of destroying the periodontal tissues. The epidemiology of CI, with its decline in incidence and its disappearance after several years, could be explained by the fact that the former equilibrium of the microflora of the once undisturbed virgin soil has been reached again and that the number of antibiotic producing actinomycetes has been anew reduced. By this reasoning and all the data available, CI should be considered as a multifactorial infectious disease, caused primarily by the anaerobic black-pigmented non-saccharolytic Bacteroides melaninogenicus, always together with the micro-anaerobic Actinomyces pyogenes. Accordingly, the onset and development of the infectious periodontitis is apparently determined by ingestion with the forage of subinhibitory concentrations of antibiotics produced in recently cultivated virgin soils. This hypothesis is supported by the recent observation of renewed outbreaks of CI-periodontitis in former CI-prone areas, following fresh cultivation after many years. The infectious nature of CI is confirmed by trials in which virginiamycin was used efficiently for the oral treatment of CI-diseased cattle. Previously it has been shown, that spiramycin and virginiamycin, used as additives in mineral supplements, prevented CI-periodontitis.