Structural Dynamics Role of AGG Interruptions in Inhibition CGG Repeat Expansion Associated with Fragile X Syndrome.

Abnormal expansion of trinucleotide CGG repeats is responsible for Fragile X syndrome. AGG interruptions in CGG repeat tracts were found in most healthy individuals, suggesting a crucial role in preventing disease-prone repeat expansion. Previous biophysics studies emphasize a difference in the secondary structure affected by AGG interruptions. However, the mechanism of how AGG interruptions impede repeat expansion remains elusive. We utilized single-molecule fluorescence resonance energy transfer spectroscopy to investigate the structural dynamics of CGG repeats and their AGG-interrupted variants. Tandem CGG repeats fold into a stem-loop hairpin structure with the capability to undergo a conformational rearrangement to modulate the length of the overhang. However, this conformational rearrangement is much more retarded when two AGG interruptions are present. Considering the significance of hairpin slippage in repeat expansion, we present a molecular basis suggesting that the internal loop created by two AGG interruptions acts as a barrier, obstructing the hairpin slippage reconfiguration. This impediment potentially plays a crucial role in curbing abnormal expansion, thereby contributing to the genomic stability.

[CiteSpace knowledge map of research hotspots and frontiers of Polygalae Radix].

In this study, the Web of Science and China National Knowledge Infrastructure(CNKI) were searched comprehensively for the literature about the research on Polygalae Radix. After manual screening, 1 207 Chinese articles and 263 English articles were included in this study. Excel was used to draw the line chart of the annual number of relevant publications. CiteSpace 6.1.R3 was used for the visual analysis of author cooperation, publishing institutions, keyword co-occurrence, keyword clustering, and bursts in the research on Polygalae Radix. The results showed that the number of articles published in Chinese and English increased linearly, which indicated the rising research popularity of Polygalae Radix. WANG J and LIU X were the authors publishing the most articles in Chinese and English, respectively. Shanxi University of Chinese Medicine and Chinese Academy of Medical Sciences were the research institutions with the largest number of Chinese and English publications in this field, respectively. The institutions publishing the relevant articles in English formed a system with the Chinese Academy of Medical Sciences as the core. According to the keywords, the research hotspots of Polygalae Radix included variety selection and breeding, quality standard, extraction and identification of active chemical components, prescription compatibility, processing, clinical medication rules, and pharmacological mechanism. The research frontiers were the molecular mechanisms of Polygalae Radix and its active components in exerting the protective effect on brain nerve, regulating receptor pathways, alleviating anxiety and Alzheimer's disease, as well as data mining and clinical medication summary. This study has reference significance for the topic selection and frontier identification of the future research on Polygalae Radix.

[Genetic diversity of protopine-6-hydroxylase in three medicinal Papaver plants].

Sanguinarine is the main active component of the Papaver plants, and protopine-6-hydroxylase(P6 H), involved in the sanguinarine biosynthetic pathway, can oxidize protopine to 6-hydroxyprotopine. The investigation on the diversity of P6 H genes in the medicinal Papaver plants contributes to the acquirement of P6 H with high activity to increase the biosynthesis of sanguinarine. Five P6 H genes in P. somniferum, P. orientale, and P. rhoeas were discovered based on the re-sequencing data of the Papaver species, followed by bioinformatics analysis. With the elongation factor 1α(EF-1α), which exhibits stable expression in the root and stem, as the internal reference gene, the transcription levels of P6H genes in roots and stems of the Papaver plants were detected by real-time fluorescent quantitative PCR. As indicated by the re-sequencing results, there were two genotypes of P6H in P. somniferum and P. orientale, respectively, and only one in P. rhoeas. The bioinformatics analysis showed that the P6 H proteins of the three Papaver plants contained the conserved domain cl12078, which is the characteristic of p450 supergene family, and transmembrane regions. The existence of signal peptide remained verification. Real-time fluorescent quantitative PCR results revealed that the transcription level of P6 H in roots of P. somniferum was about 1.44 times of that in stems(α=0.05). The present study confirmed genetic diversity of P6 H in the three medicinal Papaver plants, which lays a basis for the research on the biosynthesis pathway and mechanism of sanguinarine in Papaver species.

Long-Range Hairpin Slippage Reconfiguration Dynamics in Trinucleotide Repeat Sequences.

Trinucleotide repeat (TNR) sequences, which are responsible for several neurodegenerative genetic diseases, fold into hairpins that interfere with the protein machinery in replication or repair, thus leading to dynamic mutation -abnormal expansions of the genome. Despite their high thermodynamic stability, these hairpins can undergo configurational rearrangements, which may be crucial for continuous dynamic mutation. Here, we used CTG repeats as a model system to study their structural dynamics at the single-molecule level. A unique dynamic two-state configuration interchange was discovered over a wide range of odd-numbered CTG repeat sequences. Employing repeat-number-dependent kinetic analysis, we proposed a bulge translocation model, which is driven by the local instability and can be extended reasonably to longer (pathologically relevant) hairpins, implying the potential role in error accumulation in repeat expansion.

Failure mechanisms of 2D silicon film anodes: in situ observations and simulations on crack evolution.

An in situ optical system was used to observe the failure processes of two-dimensional silicon film anodes, suggesting a new debonding mode based on crack crushing. The stress evolution upon lithiation was quantitatively analyzed via fully coupled finite element simulations, confirming the crack crushing induced failure mechanisms in 2D silicon anodes.

High-throughput sequencing of microbial community diversity in soil, grapes, leaves, grape juice and wine of grapevine from China.

In this study Illumina MiSeq was performed to investigate microbial diversity in soil, leaves, grape, grape juice and wine. A total of 1,043,102 fungal Internal Transcribed Spacer (ITS) reads and 2,422,188 high quality bacterial 16S rDNA sequences were used for taxonomic classification, revealed five fungal and eight bacterial phyla. At the genus level, the dominant fungi were Ascomycota, Sordariales, Tetracladium and Geomyces in soil, Aureobasidium and Pleosporaceae in grapes leaves, Aureobasidium in grape and grape juice. The dominant bacteria were Kaistobacter, Arthrobacter, Skermanella and Sphingomonas in soil, Pseudomonas, Acinetobacter and Kaistobacter in grape and grapes leaves, and Oenococcus in grape juice and wine. Principal coordinate analysis showed structural separation between the composition of fungi and bacteria in all samples. This is the first study to understand microbiome population in soil, grape, grapes leaves, grape juice and wine in Xinjiang through High-throughput Sequencing and identify microorganisms like Saccharomyces cerevisiae and Oenococcus spp. that may contribute to the quality and flavor of wine.

Antiplatelet Effect of Different Loading Doses of Ticagrelor in Patients With Non-ST-Elevation Acute Coronary Syndrome Undergoing Percutaneous Coronary Intervention: The APELOT Trial.

BACKGROUND: We hypothesized that a high ticagrelor loading dose (LD) may improve platelet inhibition in patients with non-ST-elevation acute coronary syndrome (NSTE-ACS) undergoing percutaneous coronary intervention (PCI). METHODS: This interventional multicentre open-label trial randomized 278 patients with NSTE-ACS to a high (360 mg) or conventional (180 mg) ticagrelor LD. The primary outcome was the platelet reactivity index (PRI) 1 hour after administration of the LD. Secondary outcomes included PRI at 0.5 hour, 1 hour, 8 hours, and 24 hours; periprocedural myocardial infarction (PMI); major cardiac adverse events; and bleeding events. RESULTS: Two hundred sixty-two patients completed the major end points. PRI was lower in the high-LD group than in the conventional-LD group at any time point (all, P < 0.05), including at 1 hour (12.2% vs 16.7%; P = 0.023). At 0.5 hour, the high-LD group showed a lower high-platelet reactivity rate (49.6% vs 60.2%; P = 0.013) and a higher low-platelet reactivity rate (24.8% vs 12.8%; P = 0.017) than did the conventional LD group. No significant differences in the bleeding rates were found between the 2 groups (14% vs 14.3%). Four cases of PMI and 1 death in each group, as well as 1 acute myocardial infarction in the conventional LD group, occurred. There was no stroke, target lesion revascularization, or target vessel revascularization. CONCLUSIONS: Doubling the ticagrelor LD achieved faster onset and greater platelet inhibition without an increase in adverse events in patients with NSTE-ACS undergoing PCI.

Correlation between dual-axis rotational coronary angiography and intravascular ultrasound in a coronary lesion assessment.

The purpose of this study was to evaluate the accuracy of dual-axis rotational coronary angiography (DARCA) for coronary lesion assessment by directly comparing with intravascular ultrasound (IVUS). From October 2014 to December 2015, 40 patients (58 lesions) who had undergone both DARCA and IVUS were included in the image analysis. The minimum lumen diameter (MLD), lesion length, reference vessel diameter (RVD) and percent diameter stenosis at the same lesion, were identified and assessed. Significant correlation with IVUS was found for DARCA in either lesion length (r = 0.90, P < 0.001) or RVD (r = 0.81, P < 0.001) comparison. DARCA had fair correlation with IVUS for both MLD (r = 0.65, P < 0.001) and diameter stenosis (r = 0.48, P < 0.001). From the Bland-Altman plots, there was a good agreement between DARCA and IVUS regarding MLD (mean difference: -0.23 mm, 95 % limits of agreement: -0.96 to 0.50 mm) and RVD (mean difference: -0.15 mm, 95 % limits of agreement: -0.85 to 0.55 mm), while lesser agreement was found on lesion length (mean difference: -3.39 mm, 95 % limits of agreement: -12.63 to 5.85 mm) and diameter stenosis (mean difference: 4.82 %, 95 % limits of agreement: -17.05 to 26.68 %). There is an adequate correlation and agreement between DARCA and IVUS in coronary lesion assessment.

Design and Rationale of the APELOT Trial: A Randomized, Open-Label, Multicenter, Phase IV Study to Evaluate the Antiplatelet Effect of Different Loading Dose of Ticagrelor in Patients With Non-ST Acute Coronary Syndrome Undergoing Percutaneous Coronary Intervention.

Ticagrelor is a direct acting on the P2Y12 receptor blocker, which provides faster and greater platelet inhibition than clopidogrel. However, several studies suggested that in ST-segment elevation myocardial infarction patients undergoing percutaneous coronary intervention (PCI), ticagrelor exhibits initial delay in the onset of antiplatelet action. Unlike ST-segment elevation myocardial infarction, in non-ST-segment elevation acute coronary syndrome (NSTE-ACS), management pathways are highly variable, and some patients may require surgery. Effect of higher loading dose (LD) of ticagrelor in patients with NSTE-ACS in providing faster and stronger inhibition of platelet aggregation is unknown and needs to be explored further.The AntiPlatelet Effect of different Loading dOse of Ticagrelor trial is an interventional, randomized, open-label, multicenter, phase IV trial designed to evaluate whether a high LD (360 mg) of ticagrelor compared with the conventional LD (180 mg) will result in a higher inhibition of platelet aggregation without increasing bleeding events in NSTE-ACS participants undergoing PCI.A total of 250 NSTE-ACS participants will be randomized to receive a ticagrelor LD (360 or 180 mg), followed by a maintenance dose of 90 mg twice a day (bid) starting 12 hours after the LD. The primary endpoint is platelet reactivity index measured by vasodilator-stimulated phosphoprotein phosphorylation 2 hours after the LD, and the secondary endpoints include occurrence of periprocedural myocardial infarction and bleeding events.The AntiPlatelet Effect of different Loading dOse of Ticagrelor trial will provide important information on the risks and benefits of a high LD (360 mg) of ticagrelor in achieving a faster and stronger platelet inhibition compared with the conventional LD (180 mg) in NSTE-ACS patients undergoing PCI.

[Prognostic value of Picco monitoring combined with plasma microRNA-150 detection in septic shock patients].

OBJECTIVE: To assess the prognostic value of pulse indicator continuous cardiac output (Picco) monitoring combined with plasma microRNA-150 detection in septic shock patients. METHODS: Clinical data of 48 patients with septic shock admitted in General Intensive Care Unit (GICU), Shanghai First People's Hospital Songjiang Branch Affiliated to Shanghai Jiaotong University from August 2012 to August 2014 were analyzed retrospectively. The plasma levels of microRNA-150 in 48 patients at admission were assayed by qRT-PCR; and Picco monitoring was performed to record hemodynamic changes. The correlation of microRNA-150 or Picco parameters with prognosis of patients was assessed by univariate analysis and multivariate logistic analysis. Spearman correlation test showed the relationship between microRNA-150 and Picco parameters. Finally, the clinical value of combining microRNA-150 with Picco monitoring to predict the outcome of septic shock patients was analyzed by ROC curves. RESULTS: Twenty-three patients survived and 25 died in 28 d after admission in GICU. Compared with survival patients, microRNA-150 was significantly lower in fatal patients (t=-10.32, P<0.05). Univariate analysis showed that low microRNA-150 level was a risk factor for poor prognosis(OR=2.176,95% CI:1.121-4.223, P<0.05). Compared with fatal cases, the cardiac index of survival patients was higher, while EVLWI and PVPI were lower. MicroRNA-150 level was positively correlated with cardiac index (r=0.712, P<0.05), negatively correlated with EVLWI and PVPI (r=-0.622 and-0.689, both P<0.05). ROC curves showed a satisfactory diagnostic efficiency of combining microRNA-150 with Picco monitoring. CONCLUSION: Lower microRNA-150 may indicate a poor prognosis, and Picco monitoring combined with microRNA 150 detection may improve the prognostic efficiency in septic shock patients.

[Construction and tobacco transformation of COR and BBE genes hairpin RNA vector of Papaver somniferum].

The gene expressions of codeinone reductase (COR) and berberine bridge enzyme (BBE) in Papaver somniferum were blocked by RNA hairpin of RNA interference (RNAi). The complete sequences of COR and BBE genes were cloned by reverse transcription-polymerase chain reaction (RT-PCR), the results of homology comparison revealed that the cloned COR and BBE genes had high homology with the other gene family members reported in the GenBank. The target sequences of COR and BBE genes were screened in accordance with the design principle of RNAi, a 643 bp fusion gene was obtained by the method of overlapping PCR, then plant expression vector ihpRNA was constructed based on intermediate vector pHANNIBAL and plant expression vector pCEPSPS. With that 78 transgenic plants were obtained through Agrobacterium-mediated and 17 positive plants were screened by PCR, that could initially indicate that the target fragments of COR and BBE gene had been integrated into tobacco genome.