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There is little long-term follow-up information about how the number of melanoma deaths and case fatality vary over time according to the measured thickness of melanoma at diagnosis. This population-based longitudinal cohort study examines patterns and trends in case fatality among 44,531 people in Queensland (Australia) diagnosed with a single invasive melanoma (International Classification of Diseases for Oncology, third revision [ICD-O-3], C44, Morphology 872–879) between 1987 and 2011, including 11,883 diagnosed between 1987 and 1996, with up to 20 years follow-up (to December 2016). The 20-year case fatality increased by thickness, with the percentage of melanoma deaths within 20 years of diagnosis being up to 4.8% for melanomas with measured thickness <0.80 mm, 10.6% for tumors 0.8 to <1.0 mm and generally more than 30% for melanomas measuring 3 mm and more. For melanomas <1.0 mm, most deaths occurred between 5 and 20 years after diagnosis, whereas for thicker melanomas the reverse was true with most deaths occurring within the first 5 years. Five-year case fatality decreased over successive calendar time periods for melanomas <1.0 mm, but not for melanomas ≥1.0 mm. These findings demonstrate that the time course for fatal melanomas varies markedly according to tumor thickness at diagnosis. Improved understanding of the patient factors and characteristics of melanomas, in addition to tumor thickness, which increase the likelihood of progression, is needed to guide clinical diagnosis, communication with patients and ongoing surveillance pathways of patients with potentially fatal lesions.  相似文献   
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BACKGROUND/PURPOSE: Sensitive skin is a condition associated with reduced tolerance to environmental factors and/or the application of topical products, such as cosmetics. Its pathophysiology has not been fully elucidated and few data are available on its prevalence. The aim of this study was to investigate possible correlation between objective sensitivity and skin surface microrelief. METHODS: During an epidemiological survey conducted for a campaign promoted by International Society of Plastic Dermatology in Italy, 243 adult healthy subjects of both sexes with no evident dermatological disorder but positive to the lactic acid stinging test, were submitted to cyanoacrylate stratum corneum stripping from the volar forearm for the determination of the irregularity of the skin surface microrelief (irregularity skin index (ISI)). RESULTS: A significant correlation was found between intensity of symptoms in stingers and ISI (r(s)=-0.47; P<0.001). CONCLUSION: Sensitive skin is common in the healthy population. ISI can contribute towards the identification of subjects with sensitive skin and the development of more specific skin treatments for this prevalent condition.  相似文献   
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Osteonectin function in bone was investigated by infrared analysis of bones from osteonectin-null (KO) and wildtype mice (four each at 11, 17, and 36 weeks). An increase in mineral content and crystallinity in newly formed KO bone and collagen maturity at all sites was found using FTIR microspectroscopy and imaging; consistent with osteonectin's postulated role in regulating bone formation and remodeling. Mineral and matrix properties of tibias of osteonectin-null mice and their age- and background-matched wildtype controls were compared using Fourier-transform infrared microspectroscopy (FTIRM) and infrared imaging (FTIRI) at 10- and 7-mm spatial resolution, respectively. The bones came from animals that were 11, 17, and 36 weeks of age. Individual FTIRM spectra were acquired from 20 x 20 microm areas, whereas 4096 simultaneous FTIRI spectra were acquired from 400 x 400 microm areas. The FTIRM data for mineral-to-matrix, mineral crystallinity, and collagen maturity were highly correlated with the FTIRI data in similar regions. In general, the osteonectin-null mice bones had higher mineral contents and greater crystallinity (crystal size and perfection) than the age-matched wildtype controls. Specifically, the mineral content of the newly forming periosteal bone was increased in the osteonectin-null mice; the crystallinity of the cortical bone was decreased in all but the oldest animals, relative to the wildtype. The most significant finding, however, was increased collagen maturity in both the cortical and trabecular bone of the osteonectin-null mice. These spectroscopic data are consistent with a mechanism of decreased bone formation and remodeling.  相似文献   
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The action of multiple liability genes is responsible for complex phenotypes at the same time, a single gene, could control several phenotypic features. This is the case of human period 3 gene (hper3), mainly involved in the setting of the biologic clock. Some variants of this gene, besides being associated with the Delayed Sleep Phase Syndrome, showed a key role in determining evening preference rather than morning one. According to this rationale, we hypothesized that this gene could influence circadian mood fluctuations, in mood disorders. Our study demonstrated that rare genetic variants of hper3 are significantly associated to a number of mood disorders features, such as age of onset, response to SSRIs treatment, circadian mood oscillations and characteristics of temperament. These preliminary results could shed further light on the involvement of circadian genes in various aspects of physiological and psychopathological mechanisms of the brain.  相似文献   
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Beckwith-Wiedemann syndrome (BWS) is a fetal overgrowth disorder involving the deregulation of a number of genes, including IGF2 and CDKN1C, in the imprinted gene cluster on chromosome 11p15.5. In sporadic BWS cases the majority of patients have epimutations in this region. Loss of imprinting of the IGF2 gene is frequently observed in BWS, as is reduced CDKN1C expression related to loss of maternal allele-specific methylation (LOM) of the differentially methylated region KvDMR1. The causes of epimutations are unknown, although recently an association with assisted reproductive technologies has been described. To date the only genetic mutations described in BWS are in the CDKN1C gene. In order to screen for other genetic predispositions to BWS, the conserved sequences between human and mouse differentially methylated regions (DMRs) of the IGF2 gene were analyzed for variants. Four single nucleotide polymorphisms (SNPs) were found in DMR0 (T123C, G358A, T382G and A402G) which occurred in three out of 16 possible haplotypes: TGTA, CATG and CAGA. DNA samples from a cohort of sporadic BWS patients and healthy controls were genotyped for the DMR0 SNPs. There was a significant increase in the frequency of the CAGA haplotype and a significant decrease in the frequency of the CATG haplotype in the patient cohort compared to controls. These associations were still significant in a BWS subgroup with KvDMR1 LOM, suggesting that the G allele at T382G SNP (CAGA haplotype) is associated with LOM at KvDMR1. This indicates either a genetic predisposition to LOM or interactions between genotype and epigenotype that impinge on the disease phenotype.  相似文献   
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