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101.
Schnyders crystalline corneal dystrophy (SCCD) is a rare autosomal dominant eye disease with a spectrum of clinical manifestations that may include bilateral corneal clouding, arcus lipoides, and anterior corneal crystalline cholesterol deposition. We have previously performed a genome-wide linkage analysis on two large Swede-Finn families and mapped the SCCD locus to a 16-cM interval between markers D1S2633 and D1S228 on chromosome 1p36. We have collected 11 additional families from Finland, Germany, Turkey, and USA to narrow the critical region for SCCD. Here, we have used haplotype analysis with densely spaced microsatellite markers in a total of 13 families to refine the candidate interval. A common disease haplotype was observed among the four Swede-Finn families indicating the presence of a founder effect. Recombination results from all 13 families refined the SCCD locus to 2.32 Mbp between markers D1S1160 and D1S1635. Within this interval, identity-by-state was present in all 13 families for two markers D1S244 and D1S3153, further refining the candidate region to 1.58 Mbp.  相似文献   
102.

Background

Sensory substitution devices for the blind translate inaccessible visual information into a format that intact sensory pathways can process. We here tested image-to-sound conversion-based localization of visual stimuli (LEDs and objects) in 13 blindfolded participants.

Methods and Findings

Subjects were assigned to different roles as a function of two variables: visual deprivation (blindfolded continuously (Bc) for 24 hours per day for 21 days; blindfolded for the tests only (Bt)) and system use (system not used (Sn); system used for tests only (St); system used continuously for 21 days (Sc)). The effect of learning-by-doing was assessed by comparing the performance of eight subjects (BtSt) who only used the mobile substitution device for the tests, to that of three subjects who, in addition, practiced with it for four hours daily in their normal life (BtSc and BcSc); two subjects who did not use the device at all (BtSn and BcSn) allowed assessment of its use in the tasks we employed. The impact of long-term sensory deprivation was investigated by blindfolding three of those participants throughout the three week-long experiment (BcSn, BcSn/c, and BcSc); the other ten subjects were only blindfolded during the tests (BtSn, BtSc, and the eight BtSt subjects). Expectedly, the two subjects who never used the substitution device, while fast in finding the targets, had chance accuracy, whereas subjects who used the device were markedly slower, but showed much better accuracy which improved significantly across our four testing sessions. The three subjects who freely used the device daily as well as during tests were faster and more accurate than those who used it during tests only; however, long-term blindfolding did not notably influence performance.

Conclusions

Together, the results demonstrate that the device allowed blindfolded subjects to increasingly know where something was by listening, and indicate that practice in naturalistic conditions effectively improved “visual” localization performance.  相似文献   
103.
104.
Biofilm development in urinary tract catheters is an often underestimated problem. However, this form of infection leads to high mortality rates and causes significant costs in health care. Therefore, it is important to analyze these biofilms and establish avoiding strategies. In this study a continuous flow-through system for the cultivation of biofilms under catheter-associated urinary tract infection conditions was established and validated. The in vitro urinary tract catheter system implies the composition of urine (artificial urine medium), the mean volume of urine of adults (1 mL min-1), the frequently used silicone catheter (foley silicon catheter) as well as the infection with uropathogenic microorganisms like Pseudomonas aeruginosa. Three clinical isolates from urine of catheterized patients were chosen due to their ability to form biofilms, their mobility and their cell surface hydrophobicity. As reference strain P. aeruginosa PA14 has been used. Characteristic parameters as biofilm thickness, specific biofilm growth rate and substrate consumption were observed. Biofilm thicknesses varied from 105 ± 16 μm up to 246 ± 67 μm for the different isolates. The specific biofilm growth rate could be determined with a non invasive optical biomass sensor. This sensor allows online monitoring of the biofilm growth in the progress of the cultivation.  相似文献   
105.
Human colon carcinoma cells express 25-hydroxyvitamin D3-1α-hydroxylase (CYP27B1) and thus produce the vitamin D receptor (VDR) ligand 1α,25-dihydroxyvitamin D3 (1,25-D3), which can be metabolized by 25-hydroxyvitamin D3-24-hydroxylase (CYP24). Expression of VDR, CYP27B1, and CYP24 determines the efficacy of the antimitotic action of 1,25-D3 and is distinctly related to the degree of differentiation of cancerous lesions. In the present study we addressed the question of whether the effects of epidermal growth factor (EGF) and of 1,25-D3 on VDR, CYP27B1, and CYP24 gene expression in human colon carcinoma cell lines also depend on the degree of cellular differentiation. We were able to show that slowly dividing, highly differentiated Caco-2/15 cells responded in a dose-dependent manner to both EGF and 1,25-D3 by up-regulation of VDR and CYP27B1 expression, whereas in highly proliferative, less differentiated cell lines, such as Caco-2/AQ and COGA-1A and -1E, negative regulation was observed. CYP24 mRNA was inducible in all clones by 1,25-D3 but not by EGF. From the observed clonal differences in the regulatory effects of EGF and 1,25-D3 on VDR and CYP27B1 gene expression we suggest that VDR-mediated growth inhibition by 1,25-D3 would be efficient only in highly differentiated carcinomas even when under mitogenic stimulation by EGF.  相似文献   
106.
107.
Wounding of plants by insects is often mimicked in the laboratory by mechanical means such as cutting or crushing, and has not been compared directly with other forms of biotic stress such as virus infection. To compare the response of plants to these types of biotic and abiotic stress, trypsin inhibitor (TI) activity induced locally and systemically in mature tobacco (Nicotiana tabacum L.) and tomato (Lycopersicon esculentum L.) plants was followed for 12 days. In tobacco, cutting, crushing and insect feeding all induced comparable levels of TI activity of approx. 5 nmol·(mg leaf protein)?1 in wounded leaves, while tobacco mosaic virus (TMV) infection of tobacco induced 10-fold lower amounts in the infected leaves. In tomato, feeding by insects also led to the induction of a level of TI activity of 5 nmol·(mg leaf protein)?1. In contrast, both cutting and crushing of tomato leaves induced 10-fold higher amounts. These data show that biotic stress, in the form of insect feeding and TMV infection, and abiotic stress, in the form of wounding, have different effects on local levels of induced TI activity in mature tobacco and tomato plants. Irrespective of the type of wounding, in neither tobacco nor tomato could systemic induction of TI activity be observed in nearby unwounded leaves, which suggests that systemic induction of TI activity in mature tobacco and tomato plants is different from systemic TI induction in seedlings. Wounding of tobacco leaves, however, did increase the responsiveness to wounding elsewhere in the plant, as measured by an increased induction of TI activity.  相似文献   
108.
109.

Background

Socio-economic inequalities in mortality are observed at the country level in both North America and Europe. The purpose of this work is to investigate the contribution of specific risk factors to social inequalities in cause-specific mortality using a large multi-country cohort of Europeans.

Methods

A total of 3,456,689 person/years follow-up of the European Prospective Investigation into Cancer and Nutrition (EPIC) was analysed. Educational level of subjects coming from 9 European countries was recorded as proxy for socio-economic status (SES). Cox proportional hazard model''s with a step-wise inclusion of explanatory variables were used to explore the association between SES and mortality; a Relative Index of Inequality (RII) was calculated as measure of relative inequality.

Results

Total mortality among men with the highest education level is reduced by 43% compared to men with the lowest (HR 0.57, 95% C.I. 0.52–0.61); among women by 29% (HR 0.71, 95% C.I. 0.64–0.78). The risk reduction was attenuated by 7% in men and 3% in women by the introduction of smoking and to a lesser extent (2% in men and 3% in women) by introducing body mass index and additional explanatory variables (alcohol consumption, leisure physical activity, fruit and vegetable intake) (3% in men and 5% in women). Social inequalities were highly statistically significant for all causes of death examined in men. In women, social inequalities were less strong, but statistically significant for all causes of death except for cancer-related mortality and injuries.

Discussion

In this European study, substantial social inequalities in mortality among European men and women which cannot be fully explained away by accounting for known common risk factors for chronic diseases are reported.  相似文献   
110.
Melanoma is the most aggressive form of skin cancer with estimated 48,000 deaths per year worldwide. The polyphenol curcumin derived from the plant Curcuma longa is well known for its anti-inflammatory and anti-cancerogenic properties. Accordingly, dietary intake of this compound may be suitable for melanoma prevention. However, how this compound affects basic cellular mechanisms in developing melanoma still remains elusive. Therefore, the aim of this study was to investigate for the first time the impact of oral curcumin administration on the miRNA signature of engrafting melanoma. For this purpose, the effects of a 4% curcumin diet were tested on melanoma, which were established by injection of murine B78H1 cells in the flank of C57BL/6 mice. Curcumin diet or standard chow (control) was administered two weeks prior to injection of tumor cells until termination of the experiment. High throughput chip-based array analysis was deployed to detect alterations in the miRNA signature of the tumors. Curcumin treatment significantly reduced the growth of the flank tumors. Furthermore the miRNA expression signature in tumors was substantially altered by curcumin intake with mmu-miR-205-5p over 100 times higher expressed when compared to controls. The expression levels of identified key miRNAs in the tumor samples were confirmed by quantitative real-time polymerase chain reaction (qRT-PCR). A comparable expression pattern of these miRNAs was also detected in other curcumin-treated melanoma cell lines under in vitro conditions. Putative targets of curcumin-induced up-regulated miRNAs were enriched in ‘o-glycan biosynthesis’, ‘endoplasmatic reticulum protein processing’ and different cancer-related pathways. Western Blot analyses revealed that of these targets anti-apoptotic B-cell CLL/lymphoma 2 (Bcl-2) and proliferating cell nuclear antigen (PCNA) were significantly down-regulated in curcumin-treated tumors. These findings demonstrate a profound alteration of the miRNA expression signature in engrafting curcumin-treated melanoma with mmu-miR-205-5p being up-regulated most significantly.  相似文献   
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