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1.
Dysphagia ; 37(3): 578-590, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-33954811

RESUMEN

Children with dysphagia, or swallowing disorder, are at an increased risk for developing respiratory compromise, failure to thrive, and aversion. Thickened liquids can be recommended for children with dysphagia, if shown to be effective on instrumental examination and if strategies/interventions with thin liquids are not successful. Thickened liquids have many benefits, including creating a more cohesive bolus, slowing oropharyngeal transit time, and reducing aspiration. However, preparing thickened liquids with commercially available thickeners can result in poor compliance due to concerns regarding taste, texture, accessibility, cost, thickness variability, and potential negative impact of these substances on a child's immature digestive tract. The purpose of this study was to determine if liquids could be successfully thickened with widely available, commercial pureed foods, and to assess how these mixtures compare to starch and gum based thickening agents. The International Dysphagia Diet Standardisation Initiative (IDDSI) flow test was performed for each sample of puree thickened liquids, gum based thickened water, and cornstarch based thickened water. In addition, rheology testing was performed on each category of the samples to measure viscosity at various shear rates and temperatures, and to assess the presence of yield stress. Results revealed that liquids thickened with smooth textured purees were comparable to commercial starch and gum based thickeners, and may be offered as a viable alternative.


Asunto(s)
Trastornos de Deglución , Bebidas/análisis , Niño , Deglución , Humanos , Reología/métodos , Almidón , Viscosidad , Agua
2.
Conscious Cogn ; 64: 196-206, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29803700

RESUMEN

We investigated how performance in the real-life perceptual task of analog clock reading is influenced by the clock's orientation with respect to egocentric, gravitational, and visual-environmental reference frames. In Experiment 1, we designed a simple clock-reading task and found that observers' reaction time to correctly tell the time depends systematically on the clock's orientation. In Experiment 2, we dissociated egocentric from environmental reference frames by having participants sit upright or lie sideways while performing the task. We found that both reference frames substantially contribute to response times in this task. In Experiment 3, we placed upright or rotated participants in an upright or rotated immersive virtual environment, which allowed us to further dissociate vestibular from visual cues to the environmental reference frame. We found evidence of environmental reference frame effects only when visual and vestibular cues were aligned. We discuss the implications for the design of remote and head-mounted displays.


Asunto(s)
Señales (Psicología) , Orientación Espacial/fisiología , Propiocepción/fisiología , Percepción Espacial/fisiología , Vestíbulo del Laberinto/fisiología , Percepción Visual/fisiología , Femenino , Gravitación , Humanos , Masculino , Realidad Virtual
3.
J Theor Biol ; 363: 307-17, 2014 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-25193284

RESUMEN

Circadian clocks are biological oscillators that regulate daily behaviors in organisms across the kingdoms of life. Their rhythms are generated by complex systems, generally involving interlocked regulatory feedback loops. These rhythms are entrained by the daily light/dark cycle, ensuring that the internal clock time is coordinated with the environment. Mathematical models play an important role in understanding how the components work together to function as a clock which can be entrained by light. For a clock to entrain, it must be possible for it to be sped up or slowed down at appropriate times. To understand how biophysical processes affect the speed of the clock, one can compute velocity response curves (VRCs). Here, in a case study involving the fruit fly clock, we demonstrate that VRC analysis provides insight into a clock׳s response to light. We also show that biochemical mechanisms and parameters together determine a model׳s ability to respond realistically to light. The implication is that, if one is developing a model and its current form has an unrealistic response to light, then one must reexamine one׳s model structure, because searching for better parameter values is unlikely to lead to a realistic response to light.


Asunto(s)
Relojes Circadianos/fisiología , Drosophila melanogaster/fisiología , Retroalimentación Fisiológica/fisiología , Modelos Biológicos , Fotoperiodo , Animales , Factores de Tiempo
4.
J Deaf Stud Deaf Educ ; 18(4): 513-31, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23744061

RESUMEN

There is currently a unique opportunity to examine the experiences of young people who receive a second sequential cochlear implant (SCI), after only having had 1 cochlear implant (CI) for most of their lives. Eleven young people who had opted to receive an SCI were interviewed. Interpretative phenomenological analysis resulted in the identification of 6 master themes. Most participants enjoyed improved confidence and social well-being following their SCI and felt that 2 CIs were superior to 1. The majority identified themselves as hearing and deaf, but not culturally Deaf, as they strived to live in the hearing world. However, this was not without challenges and many young people experienced feelings of difference in the hearing world. These findings have clinical implications in terms of the role of clinical psychologists and other mental health professionals in CI clinics and in providing information to families making decisions about CIs. These findings add to the emergent deaf identity development literature in young people with CIs.


Asunto(s)
Implantación Coclear/psicología , Implantes Cocleares/psicología , Sordera/psicología , Personas con Deficiencia Auditiva/psicología , Psicología del Adolescente , Autoimagen , Adolescente , Niño , Sordera/cirugía , Femenino , Humanos , Masculino , Distancia Psicológica , Investigación Cualitativa , Reino Unido
5.
Ophthalmology ; 119(5): 1066-72, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22297027

RESUMEN

PURPOSE: To describe the characteristics of choroidal nevus using the enhanced depth imaging (EDI) feature of spectral-domain optical coherence tomography (OCT). DESIGN: Retrospective, observational case series. PARTICIPANTS: One hundred four eyes with choroidal nevus. METHODS: Spectral-domain EDI OCT was performed with a Heidelberg Spectralis HRA+OCT (Heidelberg Engineering, Heidelberg, Germany) using a custom scan acquisition protocol of up to 13 raster lines of 9-mm scan length with automatic real-time image averaging set at 100 images. The thickness of choroidal nevus was measured by combining Heidelberg's autosegmentation with manual segmentation. MAIN OUTCOME MEASURES: Imaging features and thickness correlation of choroidal nevus by EDI OCT versus standard ultrasonography. RESULTS: Of 104 eyes with choroidal nevus imaged with EDI OCT, 51 (49%) displayed image detail suitable for study. The remaining 53 cases were suboptimal because of statistically identified factors of age older than 60 years (P = 0.027), female gender (P = 0.008), extramacular location of nevus (P<0.001), mean distance from foveola more than 3 mm (P = 0.002), mean distance from optic disc more than 4 mm (P<0.001), and mean maximal basal diameter more than 5 mm (P = 0.006). Of the 51 suitable cases, mean nevus thickness was 685 µm (median, 628 µm; range, 184-1643 µm) by EDI OCT compared with 1500 µm (median, 1500 µm; range, 1000-2700 µm) by ultrasonography. The most common EDI OCT imaging features included partial (59%) or complete (35%) choroidal shadowing deep to the nevus, choriocapillaris thinning overlying the nevus (94%), retinal pigment epithelial (RPE) atrophy (43%), RPE loss (14%), RPE nodularity (8%), photoreceptor loss (43%), inner segment-outer segment junction (IS-OS) irregularity (37%), IS-OS loss (6%), external limiting membrane irregularity (18%), outer nuclear and outer plexiform layer irregularity (8%), and inner nuclear layer irregularity (6%). Overlying subretinal fluid was identified by EDI OCT (16%), ophthalmoscopic examination (8%), and ultrasonographic evaluation (0%). A comparison of pigmented versus nonpigmented nevus showed only 1 significant difference of more intense choroidal shadowing with pigmented nevus (P = 0.046). CONCLUSIONS: Imaging of choroidal nevus with EDI OCT enables precise measurement of tumor thickness with comparatively reduced thickness relative to ultrasonography. Using EDI OCT, 94% of choroidal nevi were found to have overlying choriocapillaris thinning.


Asunto(s)
Neoplasias de la Coroides/patología , Nevo Pigmentado/patología , Tomografía de Coherencia Óptica , Adolescente , Adulto , Anciano , Niño , Neoplasias de la Coroides/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Nevo Pigmentado/diagnóstico por imagen , Estudios Retrospectivos , Ultrasonografía , Agudeza Visual
6.
Gen Comp Endocrinol ; 171(2): 131-50, 2011 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-21216245

RESUMEN

Genome mining has provided a valuable tool for peptide discovery in many species, yet no crustacean has undergone this analysis. Currently, the only crustacean with a sequenced genome is the cladoceran Daphnia pulex, a model organism in many fields of biology. Here, we have mined the D. pulex genome for peptide-encoding genes. For each gene identified, the encoded precursor protein was deduced, and its mature peptides predicted. Twenty-four peptide-encoding genes were identified, including ones predicted to produce members of the A-type allatostatin, B-type allatostatin, C-type allatostatin, allatotropin (ATR), bursicon α, bursicon ß, calcitonin-like diuretic hormone, corazonin, crustacean cardioactive peptide, crustacean hyperglycemic hormone, ecdysis-triggering hormone, eclosion hormone (EH), insulin-like peptide (ILP), molt-inhibiting hormone, neuropeptide F, orcokinin (two genes), pigment-dispersing hormone, proctolin, red pigment concentrating hormone/adipokinetic hormone (RPCH/AKH), short neuropeptide F, SIFamide, sulfakinin, and tachykinin-related peptide (TRP) families/subfamilies. In total, 96 peptides were predicted from these genes. Our identification of isoforms of corazonin, EH, ILP, proctolin, RPCH/AKH, sulfakinin and TRP are the first for D. pulex, while our prediction of ATR from this species is the first from any crustacean. The number of peptides predicted in our study shows the power of genome mining for peptide discovery, and provides a model for future genomic analyses of the peptidomes of other crustaceans. In addition, the data presented in our study provide foundations for future molecular, biochemical, anatomical, and physiological investigation of peptidergic signaling in D. pulex and other cladoceran species.


Asunto(s)
Daphnia/genética , Genoma/genética , Neuropéptidos/genética , Animales , Hormonas de Invertebrados/genética , Oligopéptidos/genética
7.
Gen Comp Endocrinol ; 170(3): 480-6, 2011 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-21074533

RESUMEN

The Onychophora, Priapulida and Tardigrada, along with the Arthropoda, Nematoda and several other small phyla, form the superphylum Ecdysozoa. Numerous peptidomic studies have been undertaken for both the arthropods and nematodes, resulting in the identification of many peptides from each group. In contrast, little is known about the peptides used as paracrines/hormones by species from the other ecdysozoan taxa. Here, transcriptome mining and bioinformatic peptide prediction were used to identify peptides in members of the Onychophora, Priapulida and Tardigrada, the only non-arthropod, non-nematode members of the Ecdysozoa for which there are publicly accessible expressed sequence tags (ESTs). The extant ESTs for each phylum were queried using 106 arthropod/nematode peptide precursors. Transcripts encoding calcitonin-like diuretic hormone and pigment-dispersing hormone (PDH) were identified for the onychophoran Peripatopsis sedgwicki, with transcripts encoding C-type allatostatin (C-AST) and FMRFamide-like peptide identified for the priapulid Priapulus caudatus. For the Tardigrada, transcripts encoding members of the A-type allatostatin, C-AST, insect kinin, orcokinin, PDH and tachykinin-related peptide families were identified, all but one from Hypsibius dujardini (the exception being a Milnesium tardigradum orcokinin-encoding transcript). The proteins deduced from these ESTs resulted in the prediction of 48 novel peptides, six onychophoran, eight priapulid and 34 tardigrade, which are the first described from these phyla.


Asunto(s)
Hormonas de Invertebrados/genética , Invertebrados/genética , Neuropéptidos/genética , Tardigrada/genética , Secuencia de Aminoácidos , Animales , Artrópodos/genética , Biología Computacional , Perfilación de la Expresión Génica , Hormonas de Invertebrados/química , Nematodos/genética , Neuropéptidos/química
8.
Retina ; 30(1): 16-22, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19952988

RESUMEN

PURPOSE: The purpose of this study was to describe the autofluorescence (AF) features of choroidal hemangioma in 34 consecutive patients. METHODS: Standard fundus photography and AF photography (580-nm excitation, 695-nm barrier filter) were performed on all patients. The clinical features were correlated with AF features. The main outcome measures were autofluorescence features of choroidal hemangioma (intrinsic AF) and overlying retinal pigment epithelium (extrinsic AF). RESULTS: There were 27 eyes with circumscribed choroidal hemangioma (CCH) and 7 eyes with diffuse choroidal hemangioma (DCH). The mean patient age was 53 years for CCH and 15 years for DCH. Intrinsic AF of untreated CCH was generally iso-AF (n = 7, 58%) and for treated CCH was hypo-AF (n = 15, 100%). Extrinsic AF of CCH disclosed hyper-AF (orange pigment and fresh subretinal fluid) and hypo-AF (retinal pigment epithelium hyperplasia, fibrous metaplasia, and atrophy). Intrinsic AF of untreated DCH was generally hypo-AF (n = 2, 67%) and for treated DCH was hypo-AF (n = 3, 75%). Extrinsic AF of DCH was similar to CCH. CONCLUSION: Choroidal hemangioma shows little intrinsic AF. Overlying orange pigment and fresh subretinal fluid show hyper-AF and retinal pigment epithelium hyperplasia and atrophy show hypo-AF.


Asunto(s)
Neoplasias de la Coroides/diagnóstico , Angiografía con Fluoresceína , Hemangioma/diagnóstico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Braquiterapia , Niño , Neoplasias de la Coroides/terapia , Femenino , Hemangioma/terapia , Humanos , Coagulación con Láser , Masculino , Persona de Mediana Edad , Fotoquimioterapia , Fotograbar , Epitelio Pigmentado de la Retina/patología , Tomografía de Coherencia Óptica , Adulto Joven
9.
Retina ; 28(8): 1035-43, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18779708

RESUMEN

PURPOSE: To describe the autofluorescence features of choroidal nevi. DESIGN: Noncomparative case series. PARTICIPANTS: Sixty-four consecutive patients. METHODS: Correlation of fundus photography with autofluorescence photography. MAIN OUTCOME MEASURE: Autofluorescence features of choroidal nevus and overlying retinal pigment epithelium (RPE). RESULTS: The mean patient age was 62 years. The choroidal nevus was a mean of 5 mm from the optic disk and foveola. The mean tumor basal dimension was 5.0 mm and mean tumor thickness was 1.0 mm. The choroidal nevus showed hypoautofluorescence in 56%, isoautofluorescence in 19%, and hyperautofluorescence in 25%. The autofluorescence features appeared unaffected by tumor thickness, but increasing tumor base and disrupted overlying RPE appeared to produce slightly brighter autofluorescence. Nevi located in the macular region showed darker hypoautofluorescence than those outside the macular region. Overlying RPE hyperplasia, atrophy, and fibrous metaplasia were generally hypoautofluorescent. Drusen, subretinal fluid, and orange pigment were generally hyperautofluorescent. The brightest hyperautofluorescence was found with orange pigment. CONCLUSIONS: Choroidal nevus shows little intrinsic autofluorescence. Overlying RPE alterations show dramatic autofluorescence ranging from dark hypoautofluorescence of RPE atrophy to bright hyperautofluorescence of orange pigment.


Asunto(s)
Neoplasias de la Coroides/diagnóstico , Nevo/diagnóstico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Fluorescencia , Fondo de Ojo , Humanos , Masculino , Persona de Mediana Edad , Nevo Pigmentado/patología , Fotograbar , Retina/patología , Epitelio Pigmentado de la Retina/patología , Tomografía de Coherencia Óptica , Adulto Joven
10.
J Am Coll Surg ; 204(5): 831-8; discussion 838-9, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17481494

RESUMEN

BACKGROUND: Success after surgical revascularization of the lower extremities, traditionally defined by graft patency or limb salvage, fails to consider other intuitive measures of importance. The purpose of the study was to construct a more comprehensive definition of clinical success and to identify clinical predictors of failure. STUDY DESIGN: For the purpose of this study, clinical success was defined as achieving all of the following criteria: graft patency to the point of wound healing; limb salvage for 1 year; maintenance of ambulatory status for 1 year; and survival for 6 months. Between 1998 and 2004, 331 consecutive patients undergoing bypass for Rutherford III critical limb ischemia were measured for clinical success. Bivariate and logistic regression analyses were performed to determine demographic differences between success and failure. RESULTS: Despite achieving acceptable graft patency (72.7% at 36 months) and limb salvage (73.3% at 36 months), clinical success combining all 4 defined parameters was only 44.4%. Independent predictors of failure included impaired ambulatory status at presentation (odds ratio [OR] = 6.44), presence of infrainguinal disease (OR = 3.93), end-stage renal disease (OR = 2.48), presence of gangrene (OR = 2.40), and hyperlipidemia (OR = 0.56). Probability of failure in patients possessing every predictor except hyperlipidemia at presentation was 97% (OR = 150.6). CONCLUSIONS: Despite achieving acceptable graft patency and limb salvage, fewer than half of the patients achieved success when using a definition combining multiple parameters. A reappraisal of our current approach to critical limb ischemia in certain high-risk patients is warranted.


Asunto(s)
Arteriopatías Oclusivas/cirugía , Isquemia/cirugía , Extremidad Inferior/irrigación sanguínea , Evaluación de Resultado en la Atención de Salud/métodos , Enfermedades Vasculares Periféricas/cirugía , Anciano , Distribución de Chi-Cuadrado , Femenino , Humanos , Recuperación del Miembro , Modelos Logísticos , Masculino , Complicaciones Posoperatorias , Grado de Desobstrucción Vascular , Cicatrización de Heridas
11.
Retin Cases Brief Rep ; 11 Suppl 1: S219-S225, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-27824724

RESUMEN

PURPOSE: To report the clinical case of a 64-year-old man who developed several features of multiple evanescent white dot syndrome (MEWDS) but with central visual loss that persisted because of significant structural macular disease. METHODS: A case report was generated by a review of the clinical course and imaging investigations of one patient, along with review of the literature. RESULTS: A 64-year-old man noted decreased vision in the right eye for 2 weeks, associated with a central scotoma with shimmering, gauze effect of the vision. He had a good vision with normal ophthalmic examinations in the past. Ophthalmic examination revealed acuity of 20/400 with central scotoma and trace pupillary defect in the right eye, normal anterior segment, no evidence of intraocular inflammation, and fundus findings of unilateral MEWDS associated with a central zone of macular pigmentary atrophy. Autofluorescence imaging revealed reflectance changes of MEWDS as well as prominent central hypofluorescence and a zone of hyperfluorescence in inferior macula. Spectral-domain optical coherence tomography identified mild disruptions of outer retina in the regions of the MEWDS lesions and disorganization of the outer retina in the macular region overlying a shallow irregular retinal pigment epithelial detachment. The choroid demonstrated increased thickness compared with the fellow eye with suggestions of dilated outer vessels/pachyvessels. Fluorescein angiography and indocyanine green angiography revealed window defects and staining and hypocyanescence, respectively, of the central macular lesion. The MEWDS lesions resolved without evolution to chorioretinal scars, and the central vision and lesions did not benefit from a systemic steroid course or intravitreal anti-vascular endothelial growth factor therapy. CONCLUSION: This case illustrates an unusual presentation of MEWDS characterized by unilateral retinal disease presenting with symptoms and signs of profound central macular dysfunction. The clinical course did not evolve into other inflammatory retinal phenotypes, such as multifocal choroiditis or AZOOR (acute zonal occult outer retinopathy) that can sometimes develop MEWDS-like features or central disease. The central structural disease resembles some features of the pachychoroid clinical spectrum, which may have represented a superimposed diagnosis unrelated to the inflammatory phenotype.


Asunto(s)
Enfermedades de la Retina/patología , Escotoma/patología , Enfermedad Aguda , Humanos , Mácula Lútea/patología , Masculino , Persona de Mediana Edad , Campos Visuales
12.
J Vestib Res ; 22(2): 81-94, 2012 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-23000608

RESUMEN

UNLABELLED: Perceptual disturbances and motion sickness are often attributed to sensory conflict. We investigated several conditions: head movements in microgravity, periodic motions in 1-g, and locomotion with vestibular disorders. In every case, linear vectors such as linear and gravitational acceleration are crucial factors, as previously found for head movements in artificial gravity, and thus the importance of measuring linear vectors emerges as a common theme. By modeling the sensory conflict between the vestibular and somatosensory systems, we computed a measure of linear conflict known as the "Stretch Factor". We hypothesized that the motions with the greatest Stretch Factor would be the most provocative motions. RESULTS: For head movements in microgravity, the Stretch Factor can explain why fast movements are more provocative than slow movements, and why pitch movements are more provocative than yaw movements. For off-vertical-axis rotation (OVAR) in 1-g, the Stretch Factor predicts that the most provocative frequency is higher than that for vertical linear oscillation (VLO). For example, the same sensor dynamics can predict a most provocative frequency around 0.2 Hz for VLO but 0.3 Hz for OVAR, solving a mystery of this experimentally observed discrepancy. Finally, we determined that certain sensory conflict perceptions reported by vestibular patients could be explained via mathematical simulation.


Asunto(s)
Gravedad Alterada , Mareo por Movimiento/fisiopatología , Trastornos de la Sensación/fisiopatología , Enfermedades Vestibulares/fisiopatología , Ingravidez , Aceleración , Movimientos de la Cabeza , Humanos , Modelos Neurológicos , Movimiento (Física) , Rotación , Vestíbulo del Laberinto/fisiología
13.
J AAPOS ; 15(2): 167-72, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21596295

RESUMEN

PURPOSE: To describe the autofluorescent features of retinoblastomas after treatment. METHODS: Standard fundus photography and autofluorescence (AF) photography (580 nm excitation, 695 nm barrier filter) were performed on 88 tumors of 61 patients. Clinical features were correlated with autofluorescent features. RESULTS: The mean patient age at AF was 10.3 years. Of the 88 tumors, 5 (6%) were untreated, and 83 (94%) were treated. The untreated retinoblastomas showed hyperautofluorescence (hyperAF) at the site of calcification in all 5 cases (100%). The treated retinoblastomas showed intrinsic calcification in 54 cases (65%) and bright hyperAF at the site of calcification was detected in all cases. Of the 60 tumors with noncalcified remnant, the noncalcified portion was mildly hyperAF in 20 (33%), isoautofluorescence in 31 (52%), and mildly hypoautofluorescence (hypoAF) in 9 (15%). Surrounding retinal pigment epithelium hyperplasia appeared moderately hypoAF in 58 of 58 eyes (100%). Retinal pigment epithelium atrophy appeared mildly hyperAF in 29 (37%), isoautofluorescence in 33 (42%), and mildly hypoAF in 16 (21%). CONCLUSIONS: AF of retinoblastoma generally shows bright hyperAF of the calcified portion and variable AF of the noncalcified portion. The AF of calcification in retinoblastoma was confirmed by fluorescent microscopy of unstained sections of retinoblastoma after enucleation.


Asunto(s)
Calcinosis/diagnóstico , Fluorescencia , Neoplasias de la Retina/patología , Retinoblastoma/patología , Adolescente , Adulto , Atrofia , Niño , Preescolar , Femenino , Angiografía con Fluoresceína , Humanos , Hiperplasia , Masculino , Fotograbar , Neoplasias de la Retina/cirugía , Epitelio Pigmentado de la Retina/patología , Retinoblastoma/cirugía , Agudeza Visual/fisiología , Adulto Joven
14.
Artículo en Inglés | MEDLINE | ID: mdl-21798832

RESUMEN

Essentially nothing is known about the molecular underpinnings of crustacean circadian clocks. The genome of Daphnia pulex, the only crustacean genome available for public use, provides a unique resource for identifying putative circadian proteins in this species. Here, the Daphnia genome was mined for putative circadian protein genes using Drosophila melanogaster queries. The sequences of core clock (e.g. CLOCK, CYCLE, PERIOD, TIMELESS and CRYPTOCHROME 2), clock input (CRYPTOCHROME 1) and clock output (PIGMENT DISPERSING HORMONE RECEPTOR) proteins were deduced. Structural analyses and alignment of the Daphnia proteins with their Drosophila counterparts revealed extensive sequence conservation, particularly in functional domains. Comparisons of the Daphnia proteins with other sequences showed that they are, in most cases, more similar to homologs from other species, including vertebrates, than they are to those of Drosophila. The presence of both CRYPTOCHROME 1 and 2 in Daphnia suggests the organization of its clock may be more similar to that of the butterfly Danaus plexippus than to that of Drosophila (which possesses CRYPTOCHROME 1 but not CRYPTOCHROME 2). These data represent the first description of a putative circadian system from any crustacean, and provide a foundation for future molecular, anatomical and physiological investigations of circadian signaling in Daphnia.


Asunto(s)
Proteínas CLOCK/genética , Relojes Circadianos/genética , Ritmo Circadiano/genética , Daphnia/genética , Genoma , Secuencia de Aminoácidos , Animales , Proteínas CLOCK/metabolismo , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Drosophila melanogaster/fisiología , Duplicación de Gen , Datos de Secuencia Molecular , Alineación de Secuencia
15.
Retina ; 27(8): 1097-100, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18040252

RESUMEN

PURPOSE: To describe the autofluorescence features of CHRPE. DESIGN: Noncomparative case series. PARTICIPANTS: Thirteen consecutive eyes with CHRPE. METHODS: : CHRPE was studied with fundus photography and autofluorescence. Autofluorescence was judged relative to the surrounding retinal pigment epithelium. MAIN OUTCOME MEASURE: Autofluorescence features of CHRPE. RESULTS: The mean CHRPE basal dimension was 4.75 mm and the tumor location was between the macular and equator (n = 10) or equator and ora serrata (n = 3). Overall, CHRPE show hypoautofluorescence in every case and was classified as trace (n = 1), moderate (n = 6), or marked (n = 6) hypoautofluorescence. Compared to the central portion of CHRPE, the margin showed isoautofluorescence (n = 8) or trace hyperautofluorescence (n = 5). There were eight lesions with lacunae and this feature generally showed trace to moderate hyperautofluorescence (n = 6). A nonpigmented halo was present surrounding six lesions, generally showing trace hyperautofluorescence (n = 3). A pigmented halo was present surrounding eight lesions, usually showing isoautofluorescence (n = 6). CONCLUSIONS: CHRPE shows striking hypoautofluorescence and this correlates with known histopathologic evidence of lack of lipofuscin in the retinal pigment epithelium of CHRPE. The lacunae showed general mild hyperautofluorescence that might correlate with scleral autofluorescence.


Asunto(s)
Epitelio Pigmentado Ocular/patología , Enfermedades de la Retina/diagnóstico , Adolescente , Adulto , Niño , Femenino , Fluorescencia , Fondo de Ojo , Humanos , Hipertrofia/congénito , Lipofuscina/metabolismo , Masculino , Persona de Mediana Edad , Fotograbar , Epitelio Pigmentado Ocular/metabolismo , Enfermedades de la Retina/metabolismo
16.
Retina ; 27(8): 1107-11, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18040254

RESUMEN

PURPOSE: To describe the autofluorescence features of orange pigment (intracellular lipofuscin) overlying small presumed choroidal melanomas. METHODS: The diagnostic testing results (fluorescein angiography, optical coherence tomography, and fundus autofluorescence imaging) for two patients with pigmented choroidal melanoma and two patients with nonpigmented choroidal melanoma were reviewed. RESULTS: Clinically, the intracellular lipofuscin pigment appeared brown overlying the nonpigmented melanoma (two cases) and orange overlying the pigmented melanoma (two cases). Fluorescein angiography demonstrated that the lipofuscin pigment displayed fluorescein blockage in all four cases. Optical coherence tomography revealed serous retinal detachment in all four cases. Fundus autofluorescence imaging showed discrete, bright hyperautofluorescence of the orange pigment separated by hypoautofluorescent voids. The melanoma was isoautofluorescent. CONCLUSIONS: Intracellular lipofuscin overlying small choroidal melanomas shows discrete and bright hyperautofluorescence. The brightness correlates directly with the clinically visible orange pigment.


Asunto(s)
Neoplasias de la Coroides/patología , Lipofuscina/análisis , Melanoma/patología , Neoplasias de la Coroides/química , Femenino , Angiografía con Fluoresceína , Fluorescencia , Humanos , Masculino , Melanoma/química , Persona de Mediana Edad , Desprendimiento de Retina/diagnóstico , Tomografía de Coherencia Óptica
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