893 resultados para Cyst degeneration


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PURPOSE: Retinal pigment epithelium (RPE) tear is an extremely rare complication in patients with classic neovascular membranes without RPE detachment. We evaluate their incidence and functional outcome following treatment with intravitreal ranibizumab. METHODS: Observational study of 72 consecutive patients (74 eyes) treated at Jules Gonin University Eye Hospital, Lausanne, with intravitreal ranibizumab 0.5 mg for classic choroidal neovascularization (CNV) between March 2006 and February 2008. Best-corrected visual acuity (BCVA), fundus examination and optical coherence tomography were recorded monthly; fluorescein angiography was performed at baseline and repeated at least every 3 months. RESULTS: RPE tears occurred in four (5.4%) eyes temporal to the fovea, after a mean of four injections (range 3-6). Mean baseline BCVA was 0.25 decimal equivalent (logMAR 0.67) and improved despite the RPE tear to 0.6 decimal equivalent (logMAR 0.22). CONCLUSION: RPE tears following intravitreal ranibizumab injections for classic CNV can occur in about 5% of patients, even in the absence of baseline RPE detachment. Nevertheless, vision may improve provided the fovea is not involved.

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NR2E3, also called photoreceptor-specific nuclear receptor (PNR), is a transcription factor of the nuclear hormone receptor superfamily whose expression is uniquely restricted to photoreceptors. There, its physiological activity is essential for proper rod and cone photoreceptor development and maintenance. Thirty-two different mutations in NR2E3 have been identified in either homozygous or compound heterozygous state in the recessively inherited enhanced S-cone sensitivity syndrome (ESCS), Goldmann-Favre syndrome (GFS), and clumped pigmentary retinal degeneration (CPRD). The clinical phenotype common to all these patients is night blindness, rudimental or absent rod function, and hyperfunction of the "blue" S-cones. A single p.G56R mutation is inherited in a dominant manner and causes retinitis pigmentosa (RP). We have established a new locus-specific database for NR2E3 (www.LOVD.nl/eye), containing all reported mutations, polymorphisms, and unclassified sequence variants, including novel ones. A high proportion of mutations are located in the evolutionarily-conserved DNA-binding domains (DBDs) and ligand-binding domains (LBDs) of NR2E3. Based on homology modeling of these NR2E3 domains, we propose a structural localization of mutated residues. The high variability of clinical phenotypes observed in patients affected by NR2E3-linked retinal degenerations may be caused by different disease mechanisms, including absence of DNA-binding, altered interactions with transcriptional coregulators, and differential activity of modifier genes.

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The sugar beet cyst nematode, Heterodera schachtii, is a major agricultural pest. The disruption of the mating behaviour of this plant parasite in the field may provide a means of biological control, and a subsequent increase in crop yield. The H. schachtii female sex pheromone, which attracts homospecific males, was collected in an aqueous medium and isolated using high performance liquid chromatography. Characterization of the male-attractive material revealed that it was heat stable and water soluble. The aqueous medium conditioned by female H. schachtii was found to be biologically active and stimulated male behaviour in a concentration dependent manner. The activity of the crude pheromone was specific to males of H. schachtii and did not attract second stage juveniles. Results indicated that vanillic acid, a putative nematode pheromone, is not an active component of the H. schachtii sex pheromone. Male H. schachtii exhibited stylet thrusting, a poorly understood behaviour of the male, upon exposure to the female sex pheromone. This behaviour appeared to be associated with mate-finding and was used as a novel indicator of biological activity in bioassays. Serotonin, thought to be involved in the neural control of copulatory behaviour in nematodes, stimulated stylet thrusting. However, the relationship between stylet thrusting induced by the sex pheromone and stylet thrusting induced by serotonin is not clear. Extracellular electrical activity was recorded fi-om the anterior region of H. schachtii males during stylet thrusting, and appeared to be associated with this behaviour. The isolation of the female sex pheromone of H. schachtii may, ultimately, lead to the structural identification and synthesis of the active substance for use in a novel biological control strategy.

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Integrated Ocean Drilling Program (IODP) Site U1313, located at the northern boundary of the subtropical gyre in the central North Atlantic, lies within the southern part of the ice-rafted debris belt. Seventy-three palynological samples were studied from an uninterrupted interval ca. 726–603 ka (upper Marine Isotope Stage [MIS] 18 through lower MIS 15) to resolve conflicting paleoceanographic interpretations. Glacial stages were characterized by high productivity surface waters reflecting a southward shift of the Arctic Front. Sea surface salinities (SSSs) and sea surface temperatures (SSTs) were obtained by transfer functions using the Modern Analogue Technique. The lowest SSTs of 9ºC (±1.3) and 10ºC (±1.3) were recorded in glacial MIS 16 and MIS 18 respectively. However, these reconstructions are influenced by abundant heterotrophic taxa and may reflect elevated nutrient levels rather than lowered temperatures. Reworked palynomorphs uniquely indicate a Cretaceous as well as Paleozoic provenance for the first Heinrich-like events.

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This thesis Entitled Neuronal degeneration in streptozotocin induced diabetic rats: effect of aegle marmelose and pyridoxine in pancreatic B cell proliferation and neuronal survival. Diabetes mellitus, a chronic metabolic disorder results in neurological dysfunctions and structural changes in the CNS. Antioxidant therapy is a challenging but necessary dimension in the management of diabetes and neurodegenerative changes associated with it. Our results showed regional variation and imbalance in the expression pattern of dopaminergic receptor subtypes in diabetes and its role in imbalanced insulin signaling and glucose regulation. Disrupted dopaminergic signaling and increased hyperglycemic stress in diabetes contributed to the neuronal loss. Neuronal loss in diabetic rats mediated through the expression of pattern of GLUT-3, CREB, IGF-1, Akt-1, NF,B, second messengers- cAMP, cGMP, IP3 and activation of apoptotic factors factors- TNF-a,caspase-8. Disrupted dopaminergic receptor expressions and its signaling in pancreas contributed defective insulin secretion in diabetes. Activation of apoptotic factors- TNF- a,caspase-8 and defective functioning of neuronal survival factors, disrupted second messenger signaling modulated neuronal viability in diabetes. Hyperglycemic stress activated the expression of TNF-a,caspase-8, BAX and differential expression of anti oxidant enzymes- SOD and GPx in liver lead to apoptosis. Treatment of diabetic rats with insulin, Aegle marmelose and pyridoxine significantly reversed the altered dopaminergic neurotransmission, GLUT3, GLUT2, IGF-1 and second messenger signaling. Antihyperglycemic and antioxidant activity of Aegle marmelose and pyridoxine enhanced pancreatic B cell proliferation, increased insulin synthesis and secretion in diabetic rats. Thus our results conclude the neuroprotective and regenerating ability of Aegle marmelose and pyridoxine which in turn has a novel therapeutic role in the management of diabetes.

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This paper studies and compares age related hearing loss and noise-induced hearing loss in mice, and the different cell types that are affected by aging and noise.

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This paper discusses a study done to examine regeneration of spiral ganglion cells in the deafness mouse.

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Gross cystic breast disease (GCBD) is the most common benign breast disorder, but the molecular basis of cyst formation remains to be identified. If the use of aluminium-based antiperspirant salts is involved in the etiology of gross breast cyst formation, it might be expected that aluminium would be at elevated levels in human breast cyst fluid (BCF). Aluminium was measured by ICP-MS in 48 samples of BCF, 30 samples of human blood serum and 45 samples of human breast milk at different stages of lactation (colostrum, intermediate, mature). The median level of aluminium in apocrine type I BCF (n:= 27, 150 mu g I-1) was significantly higher than in transuclative type II BCF (n = 21, 32 mu g I-1; P < 0.0001). By comparison, aluminium measurements gave a median concentration of 6 mu g I-1 in human serum and 25 mu g I-1 in human breast milk, with no difference between colostrum, intermediate and mature milk. Levels of aluminium were significantly higher in both types of BCF than in human serum (P < 0.0001). However when compared with human breast milk, aluminium levels were only significantly higher in apocrine type I BCF (P < 0.0001) and not in transudative type II BCF (P = 0.152). It remains to be identified why such high levels of aluminium were found in the apocrine type I BCF and from where the aluminium originated. However, if aluminium-based antiperspirants are found to be the source and to play any causal role in development of breast cysts, then it might become possible to prevent this common breast disorder. Copyright (C) 2008 John Wiley & Sons, Ltd.

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The sternal end of the clavicle has been illustrated to be useful in aging young adults, however, no studies have investigated what age-related changes occur to the sternal end post epiphyseal fusion. In this study, three morphological features (i.e., surface topography, porosity, and osteophyte formation) were examined and scored using 564 clavicles of individuals of European ancestry (n = 318 males; n = 246 females), with known ages of 40+ years, from four documented skeletal collections: Hamann-Todd, Pretoria, St. Bride's, and Coimbra. An ordinal scoring method was developed for each of the three traits. Surface topography showed the strongest correlation with age, and composite scores (formed by summing the three separate trait scores) indicated progressive degeneration of the surface with increasing chronological age. Linear regression analyses were performed on the trait scores to produce pooled-sample age estimation equations. Blind tests of the composite score method and regression formulae on 56 individuals, aged 40+ years, from Christ Church Spitalfields, suggest accuracies of 96.4% for both methods. These preliminary results display the first evidence of the utility of the sternal end of the clavicle in aging older adult individuals. However, in the current format, these criteria should only be applied to individuals already identified as over 40 years in order to refine the age ranges used for advanced age. These findings do suggest the sternal end of the clavicle has potential to aid age estimates beyond the traditional "mature adult" age category (i.e., 46+ years), and provides several suggestions for future research.

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In order to compare the sea-surface conditions in the Black Sea during the Holocene and Eemian, sapropelic parts of marine core 22-GC3 (42°13.53′N/36°29.55′E, 838 m water depth) were studied for organic-walled dinoflagellate cyst content. The record shows a change from freshwater/brackish assemblages (Pyxidinopsis psilata, Spiniferites cruciformis, and Caspidinium rugosum) to more marine assemblages (Lingulodinium machaerophorum and Spiniferites ramosus complex) during each interglacial, due to the inflow of saline Mediterranean water. The lacustrine–marine transitions in 22-GC3 occurred at ~ 8.3 cal kyr BP during the early Holocene and ~ 128 kyr BP during the early Eemian, slightly later compared to the onset of interglacial conditions on the adjacent land. Dinoflagellate cyst assemblages reveal higher sea-surface salinity (~ 28–30) (e.g. Spiniferites pachydermus, Bitectatodinium tepikiense, and Spiniferites mirabilis) around ~ 126.5–121 kyr BP in comparison to the Holocene (~ 15–20) as well as relatively high sea-surface temperature (e.g. Tuberculodinium vancampoae, S. pachydermus, and S. mirabilis) especially at ~ 127.6–125.3 kyr BP. Establishment of high sea-surface salinity during the Eemian correlates very well with reconstructed relatively high global sea-level and is explained as a combined effect of increased Mediterranean supply and high temperatures at the beginning of the last interglacial. The observed changes in the dinocyst record highlight the importance of nutrients for the composition of the Eemian and Holocene dinocyst assemblages.

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The transcription factor REST is a key suppressor of neuronal genes in non-neuronal tissues. REST has been shown to suppress pro-neuronal microRNAs in neural progenitors indicating that REST-mediated neurogenic suppression may act in part via microRNAs. We used neural differentiation of Rest-null mouse ESC to identify dozens of microRNAs regulated by REST during neural development. One of the identified microRNAs, miR-375, was upregulated during human spinal motor neuron development. We found that miR-375 facilitates spinal motor neurogenesis by targeting the cyclin kinase CCND2 and the transcription factor PAX6. Additionally, miR-375 inhibits the tumor suppressor p53 and protects neurons from apoptosis in response to DNA damage. Interestingly, motor neurons derived from a spinal muscular atrophy patient displayed depressed miR-375 expression and elevated p53 protein levels. Importantly, SMA motor neurons were significantly more susceptible to DNA damage induced apoptosis suggesting that miR-375 may play a protective role in motor neurons.

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Purkinje cell degeneration (pcd) mice have a mutation within the gene encoding cytosolic carboxypeptidase 1 (CCP1/Nna1), which has homology to metallocarboxypeptidases. To assess the function of CCP1/Nna1, quantitative proteomics and peptidomics approaches were used to compare proteins and peptides in mutant and wild-type mice. Hundreds of peptides derived from cytosolic and mitochondrial proteins are greatly elevated in pcd mouse hypothalamus, amygdala, cortex, prefrontal cortex, and striatum. However, the major proteins detected on 2-D gel electrophoresis were present in mutant and wild-type mouse cortex and hypothalamus at comparable levels, and proteasome activity is normal in these brain regions of pcd mice, suggesting that the increase in cellular peptide levels in the pcd mice is due to reduced degradation of the peptides downstream of the proteasome. Both nondegenerating and degenerating regions of pcd mouse brain, but not wild-type mouse brain, show elevated autophagy, which can be triggered by a decrease in amino acid levels. Taken together with previous studies on CCP1/Nna1, these data suggest that CCP1/Nna1 plays a role in protein turnover by cleaving proteasome-generated peptides into amino acids and that decreased peptide turnover in the pcd mice leads to cell death.-Berezniuk, I., Sironi, J., Callaway, M. B., Castro, L. M., Hirata, I. Y., Ferro, E. S., Fricker, L. D. CCP1/Nna1 functions in protein turnover in mouse brain: Implications for cell death in Purkinje cell degeneration mice. FASEB J. 24, 1813-1823 (2010). www.fasebj.org