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Linking Penetrance and Transcription in DYT-THAP1: Insights From a Human iPSC-Derived Cortical Model
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Vanja Kastelic Ewelina Po?piech Jolanta Draus-Barini Wojciech Branicki Katja Drobni? 《Croatian medical journal》2013,54(4):381-386
Aim
To evaluate the accuracy of eye color prediction based on six IrisPlex single nucleotide polymorphisms (SNP) in a Slovenian population sample.Methods
Six IrisPlex predictor SNPs (HERC2 – rs12913832, OCA2 – rs1800407, SLC45A2 – rs16891982 and TYR – rs1393350, SLC24A4 – rs12896399, and IRF4 – rs12203592) of 105 individuals were analyzed using single base extension approach and SNaPshot chemistry. The IrisPlex multinomial regression prediction model was used to infer eye color probabilities. The accuracy of the IrisPlex was assessed through the calculation of sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and the area under the receiver characteristic operating curves (AUC).Results
Blue eye color was observed in 44.7%, brown in 29.6%, and intermediate in 25.7% participants. Prediction accuracy expressed by the AUC was 0.966 for blue, 0.913 for brown, and 0.796 for intermediate eye color. Sensitivity was 93.6% for blue, 58.1% for brown, and 0% for intermediate eye color. Specificity was 93.1% for blue, 89.2% for brown, and 100% for intermediate eye color. PPV was 91.7% for blue and 69.2% for brown color. NPV was 94.7% for blue and 83.5% for brown eye color. These values indicate prediction accuracy comparable to that established in other studies.Conclusion
Blue and brown eye color can be reliably predicted from DNA samples using only six polymorphisms, while intermediate eye color defies prediction, indicating that more research is needed to genetically predict the whole variation of eye color in humans.Prediction of human visible characteristics by genotyping informative polymorphisms in DNA opens up a new perspective in the forensic field. Multiple genes including HERC2, OCA2, MC1R, SLC24A5, SLC45A2, TYR, TYRP1, ASIP, SLC24A4, TPCN2, KITLG, and IRF4 have been associated with eye, hair, and skin color in European populations and they have been used in studies dealing with eye color prediction (1-14). Variation of iris color depends on the content of eumelanine, a brown light-absorbing biopolymer, which is present in higher concentrations in brown-eyed individuals (15,16). Although eye color is evidently a continuous variable, it has been often classified into three categories – blue, brown, and intermediate (4,14). Eye color variability is particularly striking in European populations, constituting a highly differentiating trait of potential use in forensic investigations (7,14,17). Recent studies have shown that a significant fraction of human iris color variation can be explained by polymorphisms within a single region in the human genome, comprising the evolutionary conserved HERC2 gene and the neighboring OCA2 gene located on the chromosome 15. It is assumed that the level of expression of the known pigmentation gene – OCA2 – is controlled by polymorphism rs12913832 on HERC2 locus (18,19). The remaining genes that have been shown to contribute to eye color variation are SLC24A4, SLC45A2, TYR, and IRF4 (4,20,21). However, their impact on eye color prediction is lower and it seems to vary between populations (8,14,22,23). Since such differences may potentially affect accuracy of prediction in various populations, we further addressed this issue and analyzed a population sample of individuals with defined eye color from Slovenia.Several prediction models have already been proposed to be useful in eye color prediction (4,8,9,17,23,24). Here we used six IrisPlex predictors, which were selected by Liu et al (4) from a larger set of polymorphisms potentially influencing pigmentation in humans and included into the IrisPlex prediction system (4,13,17). The IrisPlex prediction model is based on a multinomial logistic regression method and uses phenotype and genotype data from 3804 Dutch individuals. Based on these data the model gives three probabilities for blue, brown, and intermediate eye color (13). From the obtained probabilities, the most probable iris color is predicted based on recommendations given in Walsh et al (13). 相似文献95.
Jonathan Hammond Katja Gravenhorst Emma Funnell Susan Beatty Derek Hibbert Jonathan Lamb Heather Burroughs Marija Kovand?i? Mark Gabbay Christopher Dowrick Linda Gask Waquas Waheed Carolyn A Chew-Graham 《The British journal of general practice》2013,63(608):e177-e184
Background
General practice receptionists fulfil an essential role in UK primary care, shaping patient access to health professionals. They are often portrayed as powerful ‘gatekeepers’. Existing literature and management initiatives advocate more training to improve their performance and, consequently, the patient experience.Aim
To explore the complexity of the role of general practice receptionists by considering the wider practice context in which they work.Design and setting
Ethnographic observation in seven urban general practices in the north-west of England.Method
Seven researchers conducted 200 hours of ethnographic observation, predominantly in the reception areas of each practice. Forty-five receptionists were involved in the study and were asked about their work as they carried out their activities. Observational notes were taken. Analysis involved ascribing codes to incidents considered relevant to the role and organising these into related clusters.Results
Receptionists were faced with the difficult task of prioritising patients, despite having little time, information, and training. They felt responsible for protecting those patients who were most vulnerable, however this was sometimes made difficult by protocols set by the GPs and by patients trying to ‘play’ the system.Conclusion
Framing the receptionist–patient encounter as one between the ‘powerful’ and the ‘vulnerable’ gets in the way of fully understanding the complex tasks receptionists perform and the contradictions that are inherent in their role. Calls for more training, without reflective attention to practice dynamics, risk failing to address systemic problems, portraying them instead as individual failings. 相似文献96.
97.
ABSTRACTBackground: Attachment Theory has become one of the leading theories in human development. Nonetheless, empirical studies focusing on how attachment unfolds during adolescence are still scarce particularly in Spain, due to the lack of adequate measures. Objective: This study aims to validate the Important People Interview (IPI) in a shorter questionnaire version (Important People- Questionnaire; IP-Q); to analyse the changes in different affiliative bonds to multiple figures -family, peers, romantic partners – over the course of adolescence; and to identify boys’ and girls’ hierarchical ordering of their specific attachment bonds. Method: 1025 Spanish adolescents, aged 12–17 years old completed the IP-Q. Results: The results showed that the IP-Q has convergent and divergent validity. Moreover, this measure indicated that peers overtake some family members in proximity-seeking and support-seeking, but not in the overall hierarchical ordering of the attachment bond during adolescence. Conclusions: The bond with the romantic partner increases in terms of scoring on the affiliative subscales as adolescence progresses. There are significant gender differences among the hierarchy patterns of attachment for boys and girls. Developmental changes in adolescent attachment are discussed. 相似文献
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Sabina Vasaturo David E. Ploeg Guadalupe Buitrago Katja Zeppenfeld Maud Veselic-Charvat Lucia J.M. Kroft 《Korean journal of radiology》2015,16(3):668-672
A 53-year-old woman was referred for ventricular fibrillation with resuscitation. A CT-angiography showed signs of a right ventricular enlargement without obvious cause. A cardiac MRI demonstrated a dilated and hypokinetic right ventricle with extensive late gadolinium enhancement. Arrhythmogenic right ventricular dysplasia (ARVD) was suspected according to the "revised ARVD task force criteria". An endomyocardial biopsy was inconclusive. The patient developed purulent pericarditis after epicardial ablation therapy and died of toxic shock syndrome. The post-mortem pathologic examination demonstrated sarcoidosis involving the heart, lungs, and thyroid gland. 相似文献