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1.
Background: Dense deposit disease and atypical hemolytic uremic syndrome are often caused by Complement Factor H (CFH) mutations. This study describes the retinal abnormalities in dense deposit disease and, for the first time, atypical haemolytic uremic syndrome. It also reviews our understanding of drusen pathogenesis and their relevance for glomerular disease. Methods: Six individuals with dense deposit disease and one with atypical haemolytic uremic syndrome were studied from 2 to 40 years after presentation. Five had renal transplants. All four who had genetic testing had CFH mutations. Individuals underwent ophthalmological review and retinal photography, and in some cases, optical coherence tomography, and further tests of retinal function. Results: All subjects with dense deposit disease had impaired night vision and retinal drusen or whitish-yellow deposits. Retinal atrophy, pigmentation, and hemorrhage were common. In late disease, peripheral vision was restricted, central vision was distorted, and there were scotoma from sub-retinal choroidal neovascular membranes and atypical serous retinopathy. Drusen were present but less prominent in the young person with atypical uremic syndrome due to a heterozygous CFH mutation. Conclusions: Drusen are common in forms of C3 glomerulopathy caused by compound heterozygous or heterozygous CFH mutations. They are useful diagnostically but also impair vision. Drusen have an identical composition to glomerular deposits. They are also identical to the drusen of age-related macular degeneration, and may respond to the same treatments. Individuals with a C3 glomerulopathy should be assessed ophthalmologically at diagnosis, and monitored regularly for vision-threatening complications.  相似文献   
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BACKGROUND AND PURPOSE:Signs suggestive of unexpected dural venous sinus thrombosis are detectable on routine MR imaging studies without MRV. We assessed performance characteristics and interrater reliability of routine MR imaging for the diagnosis of dural venous sinus thrombosis, focusing on the superior sagittal, transverse, and sigmoid sinuses.MATERIALS AND METHODS:This case series included 350 patients with MRIs performed with contrast-enhanced MRV and 79 patients with routine MRIs performed within 48 hours of a CTV from 2008 to 2014 (total, n = 429). Routine MR images were separated from the contrast-enhanced MRVs and CTVs. Three neuroradiologists, blinded to clinical data, independently reviewed the MRIs for signs of dural venous sinus thrombosis, including high signal on sagittal T1, loss of flow void on axial T2, high signal on FLAIR, high signal on DWI, increased susceptibility effects on T2*-weighted gradient recalled-echo imaging, and filling defects on axial contrast-enhanced spin-echo T1WI and/or volumetric gradient-echo T1WI. Two neuroradiologists independently reviewed contrast-enhanced MRVs and CTVs to determine the consensus gold standard. Interrater reliability was calculated by using the κ coefficient.RESULTS:Contrast-enhanced MRV and CTV confirmed that dural venous sinus thrombosis was present in 72 of 429 cases (16.8%). The combination of routine MR sequences had an overall sensitivity of 79.2%, specificity of 89.9%, and moderate interrater reliability (κ = 0.50). The 3 readers did not have similar performance characteristics. 69.4% of positive cases had clinical suspicion of dural venous sinus thrombosis indicated on imaging requisition.CONCLUSIONS:Routine MR images can suggest dural venous sinus thrombosis with high specificity in high-risk patients, even in cases without clinical suspicion.

Dural venous sinus thrombosis (DVST) is a condition that ranges from being undiagnosed to leading to serious morbidity and mortality, including venous infarction and intracranial hemorrhage.1 DVST has a highly variable clinical presentation, from asymptomatic to acute or subacute headaches, signs or symptoms of increased intracranial pressure, focal neurologic deficits, or seizures.2,3 The diagnosis is important to consider even in younger patients, with risk factors such as genetic and acquired prothrombotic states, trauma, and infections or inflammatory conditions.1,2Although early and accurate diagnosis is important for initiation of treatment and prevention of serious complications, the median diagnostic delay from symptom onset is 7 days.14 When DVST is suspected, the current criterion standard for diagnosis is either contrast-enhanced MRV (CEMRV) or CTV.5 However, the imaging signs of unexpected DVST are seen during interpretation of routine MR imaging studies performed without dedicated CEMRV, concurrent CTV, or relevant clinical history. Typical findings might include visualization of intraluminal thrombus or a filling defect and lack of flow, or flow voids.2 Signs suggestive of DVST on standard brain MR imaging are reported in the literature with highly variable diagnostic accuracy and can be difficult to interpret in daily practice.2,68 Understanding the diagnostic performance of routine MR imaging for the evaluation of DVST is especially important when DVST is not clinically suspected or CT or MR venography has not been ordered. A false-positive interpretation of DVST based on routine MR imaging will lead to unnecessary patient anxiety, require further imaging and associated health care costs, and increase patient risk from exposure to contrast media or radiation from CTV. False-negative interpretations can lead to devastating complications such as intracranial venous hypertension, hemorrhage, and venous infarction. The aim of this study was to assess the performance characteristics and interrater reliability of signs of DVST, not including cortical or deep vein thrombosis, on routine brain MR imaging, including T1, T2, T2*-weighted gradient recalled-echo imaging (GRE), FLAIR, DWI, and postcontrast T1 sequences in comparison with CEMRV and CTV as the reference standard.  相似文献   
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The aim of our study is to investigate whether single-nucleotide dystrophin gene (DMD) variants associate with variability in cognitive functions in healthy populations. The study included 1240 participants from the Erasmus Rucphen family (ERF) study and 1464 individuals from the Rotterdam Study (RS). The participants whose exomes were sequenced and who were assessed for various cognitive traits were included in the analysis. To determine the association between DMD variants and cognitive ability, linear (mixed) modeling with adjustment for age, sex and education was used. Moreover, Sequence Kernel Association Test (SKAT) was used to test the overall association of the rare genetic variants present in the DMD with cognitive traits. Although no DMD variant surpassed the prespecified significance threshold (P<1 × 10−4), rs147546024:A>G showed strong association (β=1.786, P-value=2.56 × 10−4) with block-design test in the ERF study, while another variant rs1800273:G>A showed suggestive association (β=−0.465, P-value=0.002) with Mini-Mental State Examination test in the RS. Both variants are highly conserved, although rs147546024:A>G is an intronic variant, whereas rs1800273:G>A is a missense variant in the DMD which has a predicted damaging effect on the protein. Further gene-based analysis of DMD revealed suggestive association (P-values=0.087 and 0.074) with general cognitive ability in both cohorts. In conclusion, both single variant and gene-based analyses suggest the existence of variants in the DMD which may affect cognitive functioning in the general populations.  相似文献   
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BackgroundIn patients with phenylketonuria, stability of blood phenylalanine and tyrosine concentrations might influence brain chemistry and therefore patient outcome. This study prospectively investigated the effects of tetrahydrobiopterin (BH4), as a chaperone of phenylalanine hydroxylase on diurnal and day-to-day variations of blood phenylalanine and tyrosine concentrations.MethodsBlood phenylalanine and tyrosine were measured in dried blood spots (DBS) four times daily for 2 days (fasting, before lunch, before dinner, evening) and once daily (fasting) for 6 days in a randomized cross-over design with a period with BH4 and a period without BH4. The sequence was randomized. Eleven proven BH4 responsive PKU patients participated, 5 of them used protein substitutes during BH4 treatment. Natural protein intake and protein substitute dosing was adjusted during the period without BH4 in order to keep DBS phenylalanine levels within target range. Patients filled out a 3-day food diary during both study periods. Variations of DBS phenylalanine and Tyr were expressed in standard deviations (SD) and coefficient of variation (CV).ResultsBH4 treatment did not significantly influence day-to-day phenylalanine and tyrosine variations nor diurnal phenylalanine variations, but decreased diurnal tyrosine variations (median SD 17.6 μmol/l, median CV 21.3%, p = 0.01) compared to diet only (median SD 34.2 μmol/l, median CV 43.2%). Consequently, during BH4 treatment diurnal phenylalanine/tyrosine ratio variation was smaller, while fasting tyrosine levels tended to be higher.ConclusionBH4 did not impact phenylalanine variation but decreased diurnal tyrosine and phenylalanine/tyrosine ratio variations, possibly explained by less use of protein substitute and increased tyrosine synthesis.  相似文献   
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Context Small declines in patient‐centred attitudes during medical education have caused great concern. Although some of the self‐report scales applied have solid psychometric foundations, validity evidence for the interpretation of attitude erosion during clerkships remains weak. Objectives We sought to address this gap in a qualitative study of the relationships between scores on four commonly used attitude scales and participants’ experiences and reflections. Our aim was to gain a better understanding of the score changes from the participants’ perspectives. Methods We conducted semi‐structured interviews with 15 junior doctors from a cohort (n = 37) that had previously shown a small decline in patient‐centred attitudes during clerkships, measured on four self‐report scales. In the interviews, we explored interviewees’ experiences of their development of patient‐centredness and subsequently discussed their scale scores, particularly for those items that contributed to a rise or decline in scores. We analysed the data using a process of constant comparison among personal experiences, scale scores and participants’ explanations of score changes, applying the coding techniques of grounded theory. Results The analysis revealed important response distortions that might be responsible for small declines in scores during clerkships separately from changes in attitudes. The drastic alterations to the participants’ frame of reference, attributable to the transition to clinical practice, represented the most prominent cause of distortion. More nuanced, context‐specific, patient‐centred reasoning resulted in more neutral responses after clerkships, paradoxically causing a decline in scores. In addition to response distortions, the interviews revealed shortcomings in content validity such as an ‘extreme’ construct of patient‐centredness. Conclusions This study calls into question the validity of the interpretation of attitude erosion during clerkships. The findings suggest that small declines in scores on self‐report attitude scales are related to a recalibration of trainees’ understandings of patient‐centredness as they grow more clinically experienced. The evolved construct of patient‐centredness and the way attitudes are measured require special attention in the development of future instruments.  相似文献   
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