1. |
- Bramsen, Jesper B., et al.
(författare)
-
A large-scale chemical modification screen identifies design rules to generate siRNAs with high activity, high stability and low toxicity
- 2009
-
Ingår i: Nucleic Acids Research. - : Oxford University Press. - 0305-1048 .- 1362-4962. ; 37:9, s. 2867-2881
-
Tidskriftsartikel (refereegranskat)abstract
- The use of chemically synthesized short interfering RNAs (siRNAs) is currently the method of choice to manipulate gene expression in mammalian cell culture, yet improvements of siRNA design is expectably required for successful application in vivo. Several studies have aimed at improving siRNA performance through the introduction of chemical modifications but a direct comparison of these results is difficult. We have directly compared the effect of 21 types of chemical modifications on siRNA activity and toxicity in a total of 2160 siRNA duplexes. We demonstrate that siRNA activity is primarily enhanced by favouring the incorporation of the intended antisense strand during RNA-induced silencing complex (RISC) loading by modulation of siRNA thermodynamic asymmetry and engineering of siRNA 3'-overhangs. Collectively, our results provide unique insights into the tolerance for chemical modifications and provide a simple guide to successful chemical modification of siRNAs with improved activity, stability and low toxicity.
|
|
2. |
- Grossmann, Igor, et al.
(författare)
-
Insights into the accuracy of social scientists' forecasts of societal change
- 2023
-
Ingår i: Nature Human Behaviour. - : Springer Nature. - 2397-3374. ; 7, s. 484-501
-
Tidskriftsartikel (refereegranskat)abstract
- How well can social scientists predict societal change, and what processes underlie their predictions? To answer these questions, we ran two forecasting tournaments testing the accuracy of predictions of societal change in domains commonly studied in the social sciences: ideological preferences, political polarization, life satisfaction, sentiment on social media, and gender-career and racial bias. After we provided them with historical trend data on the relevant domain, social scientists submitted pre-registered monthly forecasts for a year (Tournament 1; N = 86 teams and 359 forecasts), with an opportunity to update forecasts on the basis of new data six months later (Tournament 2; N = 120 teams and 546 forecasts). Benchmarking forecasting accuracy revealed that social scientists' forecasts were on average no more accurate than those of simple statistical models (historical means, random walks or linear regressions) or the aggregate forecasts of a sample from the general public (N = 802). However, scientists were more accurate if they had scientific expertise in a prediction domain, were interdisciplinary, used simpler models and based predictions on prior data. How accurate are social scientists in predicting societal change, and what processes underlie their predictions? Grossmann et al. report the findings of two forecasting tournaments. Social scientists' forecasts were on average no more accurate than those of simple statistical models.
|
|
3. |
- Susat, J., et al.
(författare)
-
A 5,000-year-old hunter-gatherer already plagued by Yersinia pestis
- 2021
-
Ingår i: Cell Reports. - : Elsevier BV. - 2211-1247. ; 35:13
-
Tidskriftsartikel (refereegranskat)abstract
- A 5,000-year-old Yersinia pestis genome (RV 2039) is reconstructed from a hunter-fisher-gatherer (5300-5050 cal BP) buried at RirmukaIns, Latvia. RV 2039 is the first in a series of ancient strains that evolved shortly after the split of Y. pestis from its antecessor Y. pseudotuberculosis similar to 7,000 years ago. The genomic and phylogenetic characteristics of RV 2039 are consistent with the hypothesis that this very early Y. pestis form was most likely less transmissible and maybe even less virulent than later strains. Our data do not support the scenario of a prehistoric pneumonic plague pandemic, as suggested previously for the Neolithic decline. The geographical and temporal distribution of the few prehistoric Y. pestis cases reported so far is more in agreement with single zoonotic events.
|
|
4. |
|
|
5. |
|
|
6. |
|
|
7. |
- Eriksson, Kimmo, et al.
(författare)
-
Perceptions of the appropriate response to norm violation in 57 societies
- 2021
-
Ingår i: Nature Communications. - : Nature Research. - 2041-1723. ; 12:1
-
Tidskriftsartikel (refereegranskat)abstract
- Norm enforcement may be important for resolving conflicts and promoting cooperation. However, little is known about how preferred responses to norm violations vary across cultures and across domains. In a preregistered study of 57 countries (using convenience samples of 22,863 students and non-students), we measured perceptions of the appropriateness of various responses to a violation of a cooperative norm and to atypical social behaviors. Our findings highlight both cultural universals and cultural variation. We find a universal negative relation between appropriateness ratings of norm violations and appropriateness ratings of responses in the form of confrontation, social ostracism and gossip. Moreover, we find the country variation in the appropriateness of sanctions to be consistent across different norm violations but not across different sanctions. Specifically, in those countries where use of physical confrontation and social ostracism is rated as less appropriate, gossip is rated as more appropriate. Little is known about peoples preferred responses to norm violations across countries. Here, in a study of 57 countries, the authors highlight cultural similarities and differences in peoples perception of the appropriateness of norm violations.
|
|
8. |
|
|
9. |
- Savic, I, et al.
(författare)
-
Limbic reductions of 5-HT1A receptor binding in human temporal lobe epilepsy
- 2004
-
Ingår i: Neurology. - : Ovid Technologies (Wolters Kluwer Health). - 1526-632X .- 0028-3878. ; 62:8, s. 1343-1351
-
Tidskriftsartikel (refereegranskat)abstract
- Objective: To test the hypothesis that in mesial temporal lobe epilepsy (MTLE) there is involvement outside of mesial structures and that this involvement affects serotonin systems, thus suggesting a mechanism for affective symptoms in this population.Methods: Serotonin 5-HT1A receptor binding was studied with PET and [Carbonyl-11C]WAY-100 635 in 14 patients (6 with left-, 8 with right-sided mesial temporal lobe focus) and 14 controls. The 5-HT1A receptor binding potential was calculated for hippocampus, amygdala, orbitofrontal, insular, lateral temporal, and anterior cingulate cortex, in raphe nuclei, and in two regions presumably uninvolved in the epileptogenic process (parietal, and dorsolateral frontal neocortex).Results: The binding potential was reduced in the epileptogenic hippocampus (p = 0.0001) and amygdala (p = 0.0001) in all patients, including the six with normal [18F]FDG PET and MRI. It was also reduced in the anterior cingulate (p = 0.002), insular (p = 0.015), and lateral temporal cortex (p = 0.029) ipsilaterally to the focus, in contralateral hippocampus (p = 0.025), and in the raphe nuclei (p = 0.016).Conclusion: Patients with severe MTLE show reduced 5-HT1A receptor binding potential in the EEG-focus, and its limbic connections. [11C]WAY-100 635 PET may provide additional information to EEG, [18F]FDG PET, and MRI when evaluating patients with intractable seizures. Reductions in 5-HT1A binding in the insula and cingulate suggest a mechanism by which affective symptoms in MTLE may result.
|
|
10. |
|
|