RESUMEN
Measurement of steroids in wild pinnipeds can facilitate assessment of breeding, nutritional and stress status, and is useful in understanding behavioral responses. Even in young animals, sex steroids may be important in behavioral interactions and immune modulation. Use of saliva can avoid the large fluctuations seen in some steroids in plasma, and can negate the need for venipuncture, making it a potentially useful matrix in the wildlife. However, its utility in estimating steroid levels in wild young pinnipeds has not been evaluated. Here, we investigated the suitability of saliva for steroid hormone analysis in wild grey seal pups during their suckling and post-weaning fast periods. We collected saliva (n = 38) and plasma (n = 71) samples during the breeding season on the Isle of May, Scotland, 2012. We investigated success of sample collection, ease of preparation, accuracy and precision of analysis, and, where possible, comparability of measurements (n = 27) from saliva and plasma. Plasma sampling was rapid, whereas sampling saliva took up to five times longer. Analytical performance criteria (parallelism, accuracy, and precision (intra and inter assay co-efficient of variation (% CV)) of commercial ELISA kits to measure estradiol, testosterone and cortisol in both matrices were assessed. Estradiol and cortisol assays performed well and can be used in plasma and saliva. However, we could not confidently validate testosterone for either matrix. Saliva estradiol correlated with levels in plasma. Saliva sample preparation was faster and simpler than plasma preparation because it did not require extraction. However, given the additional time taken to obtain saliva in the wild, the possibility of blood contamination from oral damage and the lower success rate in obtaining sufficient sample for analysis, we recommend that this matrix only be used as an alternative to plasma sampling measurement in pinnipeds when animals are anaesthetized, tolerate mouth swabbing, or have been trained to accept saliva sampling in captivity.
Asunto(s)
Saliva , Phocidae , Animales , Estradiol/análisis , Hidrocortisona/análisis , Saliva/química , Esteroides/análisis , Testosterona/análisisRESUMEN
The retinal pigment epithelium (RPE) interacts closely with photoreceptors to maintain visual function. In degenerative diseases such as Stargardt disease and age-related macular degeneration, the leading cause of blindness in the developed world, RPE cell loss is followed by photoreceptor cell death. RPE cells can proliferate under certain conditions, suggesting an intrinsic regenerative potential, but so far this has not been utilised therapeutically. Here, we used E2F2 to induce RPE cell replication and thereby regeneration. In both young and old (2 and 18 month) wildtype mice, subretinal injection of non-integrating lentiviral vector expressing E2F2 resulted in 47% of examined RPE cells becoming BrdU positive. E2F2 induced an increase in RPE cell density of 17% compared with control vector-treated and 14% compared with untreated eyes. We also tested this approach in an inducible transgenic mouse model of RPE loss, generated through activation of diphtheria toxin-A gene. E2F2 expression resulted in a 10-fold increase in BrdU uptake and a 34% increase in central RPE cell density. Although in mice this localised rescue is insufficiently large to be demonstrable by electroretinography, a measure of massed retinal function, these results provide proof-of-concept for a strategy to induce in situ regeneration of RPE for the treatment of RPE degeneration.
Asunto(s)
Factor de Transcripción E2F2/genética , Técnicas de Transferencia de Gen , Terapia Genética , Degeneración Macular/terapia , Epitelio Pigmentado de la Retina/fisiopatología , Envejecimiento/genética , Envejecimiento/metabolismo , Animales , Proliferación Celular/genética , Toxina Diftérica/genética , Modelos Animales de Enfermedad , Vectores Genéticos , Ratones , Ratones Transgénicos , Fragmentos de Péptidos/genética , Regeneración , Epitelio Pigmentado de la Retina/citología , Epitelio Pigmentado de la Retina/metabolismoRESUMEN
Animals that fast during breeding and/or development, such as phocids, must regulate energy balance carefully to maximize reproductive fitness and survival probability. Adiponectin, produced by adipose tissue, contributes to metabolic regulation by modulating sensitivity to insulin, increasing fatty acid oxidation by liver and muscle, and promoting adipogenesis and lipid storage in fat tissue. We tested the hypotheses that (1) circulating adiponectin, insulin, or relative adiponectin gene expression is related to nutritional state, body mass, and mass gain in wild gray seal pups; (2) plasma adiponectin or insulin is related to maternal lactation duration, body mass, percentage milk fat, or free fatty acid (FFA) concentration; and (3) plasma adiponectin and insulin are correlated with circulating FFA in females and pups. In pups, plasma adiponectin decreased during suckling (linear mixed-effects model [LME]: T = 4.49; P < 0.001) and the early postweaning fast (LME: T = 3.39; P = 0.004). In contrast, their blubber adiponectin gene expression was higher during the early postweaning fast than early in suckling (LME: T = 2.11; P = 0.046). Insulin levels were significantly higher in early (LME: T = 3.52; P = 0.004) and late (LME: T = 6.99; P < 0.001) suckling than in fasting and, given the effect of nutritional state, were also positively related to body mass (LME: T = 3.58; P = 0.004). Adiponectin and insulin levels did not change during lactation and were unrelated to milk FFA or percentage milk fat in adult females. Our data suggest that adiponectin, in conjunction with insulin, may facilitate fat storage in seals and is likely to be particularly important in the development of blubber reserves in pups.
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Adiponectina/sangre , Tejido Adiposo/metabolismo , Ayuno/metabolismo , Insulina/sangre , Lactancia/fisiología , Leche/química , Phocidae/fisiología , Animales , Animales Lactantes , Peso Corporal , Metabolismo Energético , Femenino , Expresión GénicaRESUMEN
Seals must manage their energy reserves carefully while they fast on land to ensure that they go to sea with sufficient fuel to sustain them until they find food. Glucocorticoids (GCs) have been implicated in the control of fuel metabolism and termination of fasting in pinnipeds. Here we tested the hypothesis that dexamethasone, an artificial GC, increases fat and protein catabolism, and induces departure from the breeding colony in wild, fasting grey seal pups. A single intramuscular dose of dexamethasone completely suppressed cortisol production for 24-72 h, demonstrating activation of GC receptors. In experiment 1, we compared the effects of a single dose of dexamethasone or saline administered 10 days after weaning on fasting mass and body composition changes, cortisol, blood urea nitrogen (BUN) and glucose levels, and timing of departure from the colony. In experiment 2, we investigated the effects of dexamethasone on short-term (5 days) changes in mass loss, body composition and BUN levels. In experiment 1, dexamethasone induced a short-lived increase in mass loss, but there was no difference in timing of departure between dexamethasone- and saline-treated pups (N=10). In experiment 2, dexamethasone increased protein and water loss and prevented a decrease in BUN levels (N=11). Our data suggest changes in cortisol contribute to regulation of protein catabolism in fasting seal pups, irrespective of the sex of the animal, but do not terminate fasting. By affecting the rate of protein depletion, lasting changes in cortisol levels could influence the amount of time seal pups have to find food, and thus may have important consequences for their survival.
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Metabolismo Energético/fisiología , Ayuno/fisiología , Glucocorticoides/metabolismo , Phocidae/fisiología , Análisis de Varianza , Animales , Glucemia/metabolismo , Nitrógeno de la Urea Sanguínea , Composición Corporal/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Dexametasona/administración & dosificación , Dexametasona/farmacología , Metabolismo Energético/efectos de los fármacos , Femenino , Hidrocortisona/biosíntesis , Inyecciones Intramusculares , Masculino , Phocidae/metabolismoRESUMEN
PURPOSE: There is evidence for complement dysfunction in age-related macular degeneration (AMD). Complement activation leads to formation of the membrane attack complex (MAC), known to assemble on retinal pigment epithelial (RPE) cells. Therefore, the effect of sub-lytic MAC on RPE cells was examined with regard to pro-inflammatory or pro-angiogenic mediators relevant in AMD. METHODS: For sub-lytic MAC induction, RPE cells were incubated with an antiserum to complement regulatory protein CD59, followed by normal human serum (NHS) to induce 5% cell death, measured by a viability assay. MAC formation was evaluated by immunofluorescence and FACS analysis. Interleukin (IL)-6, -8, monocytic chemoattractant protein-1 (MCP-1), and vascular endothelial growth factor (VEGF) were quantified by enzyme-linked immunosorbent assay (ELISA). Intracellular MCP-1 was analysed by immunofluorescence, vitronectin by western blotting, and gelatinolytic matrix metalloproteinases (MMPs) by zymography. RESULTS: Incubation of RPE cells with the CD59 antiserum followed by 5% NHS induced sub-lytic amounts of MAC, verified by FACS and immunofluorescence. This treatment stimulated the cells to release IL-6, -8, MCP-1, and VEGF. MCP-1 staining, production of vitronectin, and gelatinolytic MMPs were also elevated in response to sub-lytic MAC. CONCLUSIONS: MAC assembly on RPE cells increases the IL-6, -8, and MCP-1 production. Therefore, sub-lytic MAC might have a significant role in generating a pro-inflammatory microenvironment, contributing to the development of AMD. Enhanced vitronectin might be a protective mechanism against MAC deposition. In addition, the increased expression of gelatinolytic MMPs and pro-angiogenic VEGF may be associated with neovascular processes and late AMD.
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Activación de Complemento/fisiología , Complejo de Ataque a Membrana del Sistema Complemento/fisiología , Degeneración Macular/inmunología , Epitelio Pigmentado de la Retina/metabolismo , Línea Celular , Quimiocina CCL2/biosíntesis , Humanos , Inmunohistoquímica , Interleucina-6/biosíntesis , Interleucina-8/biosíntesis , Metaloproteinasas de la Matriz/metabolismo , Factor A de Crecimiento Endotelial Vascular/biosíntesis , Factor A de Crecimiento Endotelial Vascular/metabolismo , Vitronectina/metabolismoRESUMEN
Tiletamine-zolazepam (TZ) was used at a mean (sd) dose of 1.18 (0.15) mg/kg administered intramuscularly to anaesthetise adult female grey seals (Halichoerus grypus) under field conditions at three different stages during their lactation period. A significant correlation was observed between the induction dose and time to induction (r=-0.582, P=0.011). Stage of lactation had a significant effect on condition index (CI), calculated as axial girth divided by length (P<0.001), and time to induction (P=0.009). No effect of CI on induction or recovery time was demonstrated. Respiratory rate decreased during induction and increased significantly (P<0.001) during surgical biopsy of blubber. Recovery occurred after 32.5 (11.9) minutes. Minor complications (tremor, vocalisation and mild dyspnoea) were observed in a small number of cases, none of which required treatment.
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Anestesia Intravenosa/veterinaria , Anestésicos/administración & dosificación , Lactancia/fisiología , Phocidae/fisiología , Tiletamina/administración & dosificación , Zolazepam/administración & dosificación , Periodo de Recuperación de la Anestesia , Bienestar del Animal , Animales , Animales Salvajes , Constitución Corporal/fisiología , Relación Dosis-Respuesta a Droga , Combinación de Medicamentos , Femenino , Infusiones Intravenosas/veterinaria , Frecuencia Respiratoria/efectos de los fármacosRESUMEN
Apoptosis is a form of programmed cell death that is implicated in both pathological and physiological processes throughout the body. Its imaging in vivo with intravenous radiolabelled-annexin V has been heralded as an important advance, with around 30 clinical trials demonstrating its application in the early detection and monitoring of disease, and the assessment of efficacy of potential and existing therapies. A recent development has been the use of fluorescently labeled annexin V to visualize single retinal cells undergoing the process of apoptosis in vivo with ophthalmoscopy. This has been given the acronym DARC (Detection of Apoptosing Retinal Cells). DARC so far has only been used experimentally, but clinical trials are starting shortly in glaucoma patients. Results suggest that DARC may provide a direct assessment of retinal ganglion cell health. By enabling early assessment and quantitative analysis of cellular degeneration in glaucoma, it is hoped that DARC can identify patients before the onset of irreversible vision loss. Furthermore, in addition to aiding the tracking of disease, it may provide a rapid and objective assessment of potential and effective therapies, providing a new and meaningful clinical endpoint in glaucomatous disease that is so badly needed.
Asunto(s)
Apoptosis/fisiología , Glaucoma/patología , Retina/citología , Células Ganglionares de la Retina/patología , Anexina A5 , Glaucoma/fisiopatología , Humanos , Microscopía FluorescenteRESUMEN
Nerve cell death is the key event in all neurodegenerative disorders, with apoptosis and necrosis being central to both acute and chronic degenerative processes. However, until now, it has not been possible to study these dynamically and in real time. In this study, we use spectrally distinct, well-recognised fluorescent cell death markers to enable the temporal resolution and quantification of the early and late phases of apoptosis and necrosis of single nerve cells in different disease models. The tracking of single-cell death profiles in the same living eye over hours, days, weeks and months is a significant advancement on currently available techniques. We identified a numerical preponderance of late-phase versus early-phase apoptotic cells in chronic models, reinforcing the commonalities between cellular mechanisms in different disease models. We showed that MK801 effectively inhibited both apoptosis and necrosis, but our findings support the use of our technique to investigate more specific anti-apoptotic and anti-necrotic strategies with well-defined targets, with potentially greater clinical application. The optical properties of the eye provide compelling opportunities for the quantitative monitoring of disease mechanisms and dynamics in experimental neurodegeneration. Our findings also help to directly observe retinal nerve cell death in patients as an adjunct to refining diagnosis, tracking disease status and assessing therapeutic intervention.
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Apoptosis , Enfermedades Neurodegenerativas/diagnóstico , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/metabolismo , Animales , Modelos Animales de Enfermedad , Maleato de Dizocilpina/farmacología , Ratones , Necrosis , Células Ganglionares de la Retina/metabolismo , Células Ganglionares de la Retina/patologíaRESUMEN
PURPOSE: Outer nuclear apoptosis following acute light exposure has previously only been shown histologically. This study investigated whether in vivo detection with DARC (detection of apoptosing retinal cells) technology could identify cells undergoing apoptosis. METHODS: Acute blue light damage (lambda=405 nm; 3.2 mW/cm(2)) was applied to eyes of dark Agouti rats over 2 h. In vivo retinal imaging using confocal scanning laser ophthalmoscopy was performed before and directly after light exposure as well as after 24 h of dark adaptation. Development of retinal cell apoptosis was then assessed using intravitreal fluorescent-labeled annexin-5 with DARC technology in vivo. RESULTS: Directly after light exposure, no pathological retinal changes were observed by in vivo imaging. However, retinal flattening and the development of apoptosis within the irradiated retina occurred 1 day later and following dark adaptation. Confocal live scanning through the exposed retina revealed hyperfluorescent apoptotic cells at the level of the outer retina. Histological analysis confirmed the occurrence of photoreceptor cell death and the development of cellular damage at the outer retina. DISCUSSION: This study confirms acute light-induced outer nuclear apoptosis using in vivo DARC technology. This may open new and promising ways to assess programmed cell death of the photoreceptor cells, which - until now - was possible only with postmortem analysis.
Asunto(s)
Apoptosis/efectos de la radiación , Microscopía Confocal/métodos , Microscopía Fluorescente/métodos , Estimulación Luminosa/métodos , Retina/citología , Retina/efectos de la radiación , Animales , Células Cultivadas , Luz , Masculino , RatasRESUMEN
CONTEXT: The incidence of recently defined outcome of chronic kidney disease (CKD) has not been widely reported in type 1 diabetes. OBJECTIVE: To examine the prospective association between baseline glycosylated hemoglobin levels and the 16-year incidence of CKD and end-stage renal disease (ESRD) in type 1 diabetes. DESIGN: Prospective cohort study of type 1 diabetes individuals. SETTING: Community based in southwestern Wisconsin. PARTICIPANTS: 547 younger-onset type 1 diabetes individuals who were free of CKD at baseline (1984-86). MAIN OUTCOME MEASURES: Development of CKD (defined as estimated glomerular filtration rate<60 ml/min/1.73 m(2) or ESRD [history of dialysis or renal transplantation]) over 16-year follow-up period, among individuals free of CKD at baseline. Alternate outcome was 16-year incident ESRD. RESULTS: After 16 years of follow-up, there were 158 cases of CKD and 37 cases of ESRD in our cohort. The 16-year cumulative incidence of CKD was 31.7 percent. Elevated glycosylated hemoglobin levels were associated with incident CKD and ESRD in separate models. Multivariable odds ratio (OR) [95% confidence intervals (CI)] comparing the highest quartile of glycosylated hemoglobin (11-15.3%) to the lowest quartile (6-8.6%) was 6.44 (3.61-11.51), p-trend<0.0001 for incident CKD and 21.87 (2.84-168.39), p-trend<0.0001 for ESRD. CONCLUSIONS: Higher baseline glycosylated hemoglobin levels are independently associated with incident CKD and ESRD, among individuals with type 1 diabetes.
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Diabetes Mellitus Tipo 1/sangre , Nefropatías Diabéticas/epidemiología , Hemoglobina Glucada/metabolismo , Fallo Renal Crónico/epidemiología , Nefropatías Diabéticas/sangre , Tasa de Filtración Glomerular , Humanos , Incidencia , Fallo Renal Crónico/sangreRESUMEN
Annexins comprise a conserved family of proteins characterised by their ability to bind and order charged phospholipids in membranes, often in response to elevated intracellular calcium. The family members (there are at least 12 in humans) have become specialised over evolutionary time and are involved in a diverse range of cellular functions both inside the cell and extracellularly Although a mutation in an annexin has never been categorically proven to be the cause of a disease state, they have been implicated in pathologies as diverse as autoimmunity, infection, heart disease, diabetes and cancer. 'Annexinopathies' were first described by Jacob H. Rand to describe the pathological sequelae in two disease states, the overexpression of annexin 2 in a patients with a haemorrhagic form of acute promyelocytic leukaemia, and the under-expression of annexin 5 on placental trophoblasts in the antiphospholipid syndrome. In this chapter we will outline some of the more recent observations in regard to these conditions, and describe the involvement of annexins in some other major causes of human morbidity.
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Anexinas , Animales , Anexina A2/fisiología , Anexinas/biosíntesis , Anexinas/fisiología , Síndrome Antifosfolípido/fisiopatología , Infecciones Bacterianas/fisiopatología , Fibrosis Quística/fisiopatología , Diabetes Mellitus/fisiopatología , Enfermedades Genéticas Ligadas al Cromosoma X/fisiopatología , Cardiopatías/fisiopatología , Humanos , Inflamación/fisiopatología , Enfermedades Renales/fisiopatología , Leucemia Promielocítica Aguda/sangre , Leucemia Promielocítica Aguda/fisiopatología , Neoplasias/fisiopatología , Virosis/fisiopatologíaRESUMEN
Muscle contraction implies flexibility in combination with force resistance and requires a high degree of sarcolemmal organization. Smooth muscle cells differentiate largely from mesenchymal precursor cells and gradually assume a highly periodic sarcolemmal organization. Skeletal muscle undergoes an even more striking differentiation programme, leading to cell fusion and alignment into myofibrils. The lipid bilayer of each cell type is further segregated into raft and non-raft microdomains of distinct lipid composition. Considering the extent of developmental rearrangement in skeletal muscle, we investigated sarcolemmal microdomain organization in skeletal and smooth muscle cells. The rafts in both muscle types are characterized by marker proteins belonging to the annexin family which localize to the inner membrane leaflet, as well as glycosyl-phosphatidyl-inositol (GPI)-anchored enzymes attached to the outer leaflet. We demonstrate that the profound structural rearrangements that occur during skeletal muscle maturation coincide with a striking decrease in membrane lipid segregation, downregulation of annexins 2 and 6, and a significant decrease in raft-associated 5'-nucleotidase activity. The relative paucity of lipid rafts in mature skeletal in contrast to smooth muscle suggests that the organization of sarcolemmal microdomains contributes to the muscle-specific differences in stimulatory responses and contractile properties.
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Diferenciación Celular/fisiología , Microdominios de Membrana/fisiología , Músculo Esquelético/embriología , Sarcolema/fisiología , Anexinas/metabolismo , Biomarcadores , Señalización del Calcio/fisiología , HumanosRESUMEN
The Objective of this study was to determine whether peak expiratory flow rate is a predictor of complications of diabetes. Peak expiratory flow rate was measured at the 10-year follow-up (third examination) of a cohort of persons with younger-onset diabetes. The relationships of progression of diabetic retinopathy by two steps, progression to proliferative retinopathy and of incidences of macular edema, sore or ulcers on feet or ankles, lower extremity amputation, proteinuria, and cardiovascular disease 4 years after this examination with respect to peak expiratory flow rate were evaluated. Study procedures including measurements of blood pressure, height and weight, grading of fundus photographs, peak expiratory flow rate, urinalysis, and medical history were performed according to standard protocols. Peak expiratory flow rate was not associated in univariate analyses with progression of retinopathy, incidences of proliferative retinopathy, macular edema or lower extremity amputation, sores or ulcers on feet or ankles, gross proteinuria, or self-reported cardiovascular disease. However, when using multivariable models to include the effects of other risk factors, peak expiratory flow rate was significantly associated with the combined incidences of sores or ulcers on feet and ankles, or lower extremity amputations (OR=0.61, 95% CI 0.42-0.88). These data suggest that peak expiratory flow rate is a predictor of subsequent complications in the lower extremities in those with long duration of younger-onset diabetes. Evaluating this association in an incipient cohort would illuminate whether the relationship we found is likely to be causal.
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Complicaciones de la Diabetes , Diabetes Mellitus/fisiopatología , Retinopatía Diabética/epidemiología , Ápice del Flujo Espiratorio , Adulto , Amputación Quirúrgica , Enfermedades Cardiovasculares/epidemiología , Pie Diabético/epidemiología , Retinopatía Diabética/diagnóstico , Edema/epidemiología , Femenino , Humanos , Modelos Logísticos , Mácula Lútea , Masculino , Proteinuria/epidemiología , Wisconsin/epidemiologíaRESUMEN
OBJECTIVE: To examine correlates of peak expiratory flow rate in people with type 1 diabetes and to evaluate the relationship of peak expiratory flow rate to mortality. RESEARCH DESIGN AND METHODS: A cohort study that was originally designed to determine the prevalence, incidence, and severity of diabetic retinopathy also provided the opportunity to measure peak expiratory flow rate. This was first measured at a 10-year follow-up and was evaluated in regard to risk factors for microvascular complications of diabetes. Mortality during 6 years of follow-up after the measurement was also ascertained. RESULTS: In multivariable analysis, peak expiratory flow rate was associated with sex, age, height, BMI, history of cardiovascular disease, pulse rate, duration of diabetes, glycosylated hemoglobin, and end-stage renal disease. Peak expiratory flow rate was significantly associated with survival in categorical analyses. Even after considering age, sex, renal disease, history of cardiovascular disease, respiratory symptoms, duration of diabetes, cigarette smoking, and hypertension, peak expiratory flow rate was still significantly related to survival (hazard ratio 0.61 [95% CI 0.46-0.82]). CONCLUSIONS: These data indicate that peak expiratory flow rate is associated with risk factors for other complications of diabetes. In addition, peak expiratory flow rate is a significant predictor of survival over even a relatively short period of time (6 years) in patients with younger-onset diabetes.
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Retinopatía Diabética/epidemiología , Ápice del Flujo Espiratorio/fisiología , Adolescente , Adulto , Edad de Inicio , Antropometría , Estudios de Cohortes , Retinopatía Diabética/mortalidad , Retinopatía Diabética/fisiopatología , Femenino , Estudios de Seguimiento , Hemoglobina Glucada/análisis , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Proteinuria/epidemiología , Análisis de Regresión , Factores de Riesgo , Fumar , Tasa de Supervivencia , Factores de Tiempo , Wisconsin/epidemiologíaRESUMEN
Annexin 2 is a Ca(2+) binding protein that binds to and aggregates secretory vesicles at physiological Ca(2+) levels [1] and that also associates Ca(2+) independently with early endosomes [2, 3]. These properties suggest roles in both exocytosis and endocytosis, but little is known of the dynamics of Annexin 2 distribution in live cells during these processes. We have used evanescent field microscopy to image Annexin 2-GFP in live, secreting rat basophilic leukemia cells and in cells performing pinocytosis. Although we found no evidence of Annexin 2 involvement in exocytosis, we observed an enrichment of Annexin 2-GFP in actin tails propeling macropinosomes. The association of Annexin 2-GFP with rocketing macropinosomes was specific because Annexin 2-GFP was absent from the actin tails of rocketing Listeria. This finding suggests that the association of Annexin 2 with macropinocytic rockets requires native pinosomal membrane. Annexin 2 is necessary for the formation of macropinocytic rockets since overexpression of a dominant-negative Annexin 2 construct abolished the formation of these structures. The same construct did not prevent the movement of Listeria in infected cells. These results show that recruitment of Annexin 2 to nascent macropinosome membranes 16656is an essential prerequisite for actin polymerization-dependent vesicle locomotion.
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Actinas/fisiología , Anexina A2/fisiología , Pinocitosis/fisiología , Animales , Exocitosis/fisiología , Microscopía Confocal , Movimiento , Presión Osmótica , Ratas , Proteínas Recombinantes de Fusión/fisiología , Células Tumorales CultivadasRESUMEN
AIM: To describe the relation between pulse rate and incident diabetic retinopathy. METHODS: Population based cohort study of people with diabetes. Resting pulse rate was measured in 30 second intervals. Diabetic retinopathy was evaluated from masked gradings of fundus photographs. RESULTS: People with higher pulse rates were more likely to have 4 year progression of retinopathy, progression to proliferative retinopathy, and incident macular oedema than those with lower pulse rates. However, these associations were attenuated after controlling for blood pressure, glycosylated haemoglobin, and other risk factors. CONCLUSION: Pulse rate may be a clinical indicator of overall risk of diabetic retinopathy, but is not independently associated with the condition.
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Retinopatía Diabética/fisiopatología , Edema Macular/fisiopatología , Pulso Arterial , Adulto , Presión Sanguínea , Diabetes Mellitus Tipo 1/fisiopatología , Diabetes Mellitus Tipo 2/fisiopatología , Retinopatía Diabética/diagnóstico , Progresión de la Enfermedad , Hemoglobina Glucada/análisis , Humanos , Modelos Logísticos , Estudios Longitudinales , Edema Macular/diagnóstico , Factores de RiesgoRESUMEN
PURPOSE: To estimate the prevalence of asteroid hyalosis and to examine correlates of asteroid hyalosis in a population-based cohort. METHODS: The population of Beaver Dam, Wisconsin, that was 43 to 86 years of age was examined from 1988 to 1990 (n = 4926). The population is predominantly white (99.4%) northern European. Asteroid hyalosis was determined from stereoscopic fundus photographs of three standard fields. RESULTS: Fundus photographs were gradable in 4747 subjects. Asteroid hyalosis was present in 1.2% (95% confidence interval, 0.9,1.5%). In subjects in which it was present, asteroid hyalosis was bilateral in 9%. Prevalence increased significantly (P <.001) with age from 0.2% in subjects 43 to 54 years to 2.9% in subjects 75 to 86 years. After adjusting for age, men were more likely (1.8%) to have asteroid hyalosis than women (0.8%). After adjusting for age and sex, asteroid hyalosis was significantly more likely to be found in subjects with greater body mass (P =.02) and higher alcohol consumption (P =.03). There were nonsignificant trends with systolic blood pressure (P =.07), serum cholesterol (P =.09), and serum albumin (P =.09). It was not significantly associated (P >.05) with diastolic blood pressure, hypertension, diabetes, cardiovascular disease history, high-density-lipoprotein cholesterol, serum calcium, cigarette smoking, physical activity, intraocular pressure, or refractive error. These relationships were confirmed in a multivariable logistic model. CONCLUSIONS: The current study documents the infrequency of asteroid hyalosis in the population as graded from three photographic fields of the fundus. It does not support previous observations of an association of asteroid hyalosis with diabetes or refractive error. The relevance of the new associations reported (body mass, alcohol) remains to be determined.
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Oftalmopatías/epidemiología , Cuerpo Vítreo/patología , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Envejecimiento/patología , Oftalmopatías/patología , Femenino , Fondo de Ojo , Humanos , Masculino , Persona de Mediana Edad , Fotograbar , Prevalencia , Distribución por Sexo , Wisconsin/epidemiologíaRESUMEN
PURPOSE: To investigate the relationship between socioeconomic factors and the 5-year incidence of age-related maculopathy. METHODS: The Beaver Dam Eye Study, a population-based cohort study, examined 3681 adults (range, 43-86 years of age at baseline) living in Beaver Dam, Wisconsin, at baseline and 5 years later. Standardized protocols for physical examination, including administration of a questionnaire that included questions regarding income, education level, and status and type of employment, and fundus photography to determine age-related maculopathy, were performed. RESULTS: While controlling for age and sex, less education, and being in a service-related occupation compared with a white collar professional occupation, was associated (P <.05) with the incidence of early age-related maculopathy. CONCLUSION: These data show an association of education and occupation but not income with the incidence of early age-related maculopathy that appears independent of smoking or vitamin supplement use status.
Asunto(s)
Degeneración Macular/epidemiología , Factores Socioeconómicos , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Escolaridad , Femenino , Humanos , Incidencia , Renta , Masculino , Persona de Mediana Edad , Ocupaciones , Encuestas y Cuestionarios , Wisconsin/epidemiologíaRESUMEN
OBJECTIVES: To examine the association of the 25-item National Eye Institute Visual Function Questionnaire (NEI-VFQ-25) overall and specific scale scores with visual acuity, diabetic retinopathy, and other characteristics, in a cohort of persons with type 1 diabetes. DESIGN: Population-based cohort study. SETTING: An 11-county area in southern Wisconsin. PARTICIPANTS: Six hundred two persons with diabetes whose conditions were diagnosed when they were younger than 30 years and who were currently taking insulin participated in baseline, 4-year, 10-year, and 14-year follow-up examinations. MAIN OUTCOME MEASURES: An interview that consisted of the 25-item NEI-VFQ was completed. Visual acuity was measured by the Early Treatment of Diabetic Retinopathy Study (ETDRS) protocol and the presence and severity of retinopathy and macular edema were detected by masked grading of stereoscopic color fundus photographs using the modified Airlie House classification and the ETDRS retinopathy severity scheme. RESULTS: Univariate analyses revealed that the total NEI-VFQ-25 score was lower in persons who were older, had a longer duration of diabetes, higher glycosylated hemoglobin, were in renal failure, had a history of cardiovascular disease, hypertension, or amputation of a lower limb, had poorer visual acuity, more severe diabetic retinopathy, macular edema, glaucoma, cataract, abnormalities in tactile sensation or temperature sensitivity, smoked more total pack-years, led a more sedentary lifestyle, and had poor peak expiratory flow. In multivariate analyses, while controlling for the physical and mental component scores from the Medical Outcomes Survey 36-Item Short-Form Health Survey as measures of comorbidity, lower total NEI-VFQ-25 scores were independently associated with poorer visual acuity, more severe retinopathy, older age, history of loss of tactile sensation, and more total pack-years of cigarettes smoked. CONCLUSIONS: In this cross-sectional study, the 25-item NEI-VFQ seems to be strongly associated with vision, independent of severity of retinopathy and other complications associated with type 1 diabetes. It may be a useful measure of health-related quality of life as it relates to vision in epidemiological studies and clinical trials in persons with diabetes.