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Abstract Aims The long‐term cost‐effectiveness of MitraClip in heart failure patients with secondary mitral regurgitation is still unclear. This study aimed to evaluate the long‐term cost‐effectiveness of MitraClip added to guideline‐directed medical therapy vs. guideline‐directed medical therapy alone in heart failure patients with secondary mitral regurgitation from the perspective of the healthcare systems of mainland China, the United Kingdom, Germany, and the United States. Methods and results A two‐stage (decision + Markov) model was built. Health utilities were defined by the New York Heart Association class, heart failure re‐hospitalization, and death and were calculated based on the 5 year follow‐up results of the Cardiovascular Outcomes Assessment of the MitraClip Percutaneous Therapy for Heart Failure Patients With Functional Mitral Regurgitation trial. Direct healthcare costs were derived from the nationally representative data. Future utilities and costs were discounted at country‐specific rates. The primary outcome was the lifetime incremental cost‐effectiveness ratio. The mean age of the base case in our model was 72.2 years. Over a lifetime horizon, treatment with MitraClip was associated with 829 fewer heart failure re‐hospitalizations per 1000 treated patients. The MitraClip treatment was associated with incremental quality‐adjusted life‐year gains of 0.71, 0.76, 0.78, and 0.78, as well as incremental cost‐effectiveness ratios of ¥468 462, £28 910, €26 045, and $71 199 per quality‐adjusted life‐year for a lifetime horizon in mainland China, the United Kingdom, Germany, and the United States, respectively. In probabilistic sensitivity analysis, 0.2%, 59.4%, 99.6%, and 84.7% of patients were cost‐effective in mainland China, the United Kingdom, Germany, and the United States at the country‐specific willingness‐to‐pay thresholds. Conclusions MitraClip + guideline‐directed medical therapy was cost‐effective in heart failure patients with secondary mitral regurgitation in the United Kingdom, Germany, and the United States, but not in mainland China from the perspective of the national healthcare system.

Abstract The main protease (Mpro) of SARS-CoV-2 is critical for viral function and a key drug target. Mpro is only active when reduced; turnover ceases upon oxidation but is restored by re-reduction. This suggests the system has evolved to survive periods in an oxidative environment, but the mechanism of this protection has not been confirmed. Here, we report a crystal structure of oxidized Mpro showing a disulfide bond between the active site cysteine, C145, and a distal cysteine, C117. Previous work proposed this disulfide provides the mechanism of protection from irreversible oxidation. Mpro forms an obligate homodimer, and the C117-C145 structure shows disruption of interactions bridging the dimer interface, implying a correlation between oxidation and dimerization. We confirm dimer stability is weakened in solution upon oxidation. Finally, we observe the protein’s crystallization behavior is linked to its redox state. Oxidized Mpro spontaneously forms a distinct, more loosely packed lattice. Seeding with crystals of this lattice yields a structure with an oxidation pattern incorporating one cysteine-lysine-cysteine (SONOS) and two lysine-cysteine (NOS) bridges. These structures further our understanding of the oxidative regulation of Mpro and the crystallization conditions necessary to study this structurally.

Abstract Background The prognostic value of triglyceride-glucose (TyG) index in general type 2 diabetes mellitus (T2DM) patients is still unclear. Therefore, we aimed to determine the associations between TyG and all-cause/cause-specific death in a T2DM cohort and explore whether such associations would be modified by age. Methods A total of 3,376 patients with T2DM from the National Health and Nutrition Examination Survey (NHANES) 1999–2018 were selected and divided into the younger group (

The paper adopts the architecture of "ADC+FPGA", designs and develops a 1 GS/s, 16-bit high-speed and high-precision data acquisition system(DAS), which realized the purpose of using a single channel to measure large dynamic range(DR>1 000) signals. The study uses two sysref modes, which are periodic sysref mode and pulse sysref mode, to establishe a stable JESD204B link with a deterministic delay. The differences in the sampled data spectrum between the two modes is presented, and the considerations of hardware design and firmware design are given. The paper recommends that the periodic sysref mode be used to establish JESD204B link. By analyzing the time-domain waveform and frequency spectrum of the sampled data, the conclusion that the ADC chip contains 4 on-chip ADC channels is verified.

Long-wavelength pulses from the Swiss X-ray free-electron laser (XFEL) have been used for de novo protein structure determination by native single-wavelength anomalous diffraction (native-SAD) phasing of serial femtosecond crystallography (SFX) data. In this work, sensitive anomalous data-quality indicators and model proteins were used to quantify improvements in native-SAD at XFELs such as utilization of longer wavelengths, careful experimental geometry optimization, and better post-refinement and partiality correction. Compared with studies using shorter wavelengths at other XFELs and older software versions, up to one order of magnitude reduction in the required number of indexed images for native-SAD was achieved, hence lowering sample consumption and beam-time requirements significantly. Improved data quality and higher anomalous signal facilitate so-far underutilized de novo structure determination of challenging proteins at XFELs. Improvements presented in this work can be used in other types of SFX experiments that require accurate measurements of weak signals, for example time-resolved studies.

Hot deformation is a way to effectively improve strength and plasticity of multiphase steels simultaneously, thereby, improving mechanical properties of multiphase steels. Hot deformation affects martensitic transformation mechanism, microstructure, and mechanical properties because it increases retained austenite content and improves stability of multiphase steels. Moreover, hot deformation plays a role in dislocation multiplication, and fine grain strengthening; it can reduce bainite transformation driving force, reduce bainite transformation point, and result in small multiphase organization after quenching-partitioning process. The result can significantly improve the properties of materials. The effects of high-temperature deformation on the stability of room-temperature microstructure, mechanical property, and retained austenite under treatment of IQ&PB (intercritical annealing-quenching and partitioning within the bainitic region) and DIQ&PB (intercritical deformation-intercritical annealing-quenching and partitioning within the bainitic region) processes were studied using scanning electron microscopy (SEM), transmission electron microscope (TEM), electron probe X-ray microanalyser (EPMA), X-ray diffraction (XRD), and tensile testing machine. The results show that dislocation density increases from 0.290×1014 to 1.286×1014 m-2 after 15% compression deformation, and the respective concentrations of C and Cu element enrichment in martensite (the original austenite) increases. Overall, dislocation multiplication produced by high-temperature deformation significantly promotes elemental distribution. After the deformation, the size of bainite lath shortenes and its width increases by 0.1 μm, the volume of the bainite transition increased by 14%, and the size of the polygonal ferrite significantly decreases under the DIQ&PB treatment. In terms of mechanical properties, the tensile strength increases by 132.85 MPa, and the elongation increases by 7%; the strength and ductility product reaches 25435 MPa·% after intercritical deformation heat treatment. The volume fraction of retained austenite increases from 7.8% to 8.99%, and the mass fraction of carbon in the retained austenite increases from 1.05% to 1.31% after compression deformation.

Serial crystallography was developed for protein crystal data collection with X-ray free-electron lasers. Here the authors present several examples which show that serial crystallography using high-viscosity injectors can also be routinely employed for room-temperature data collection at synchrotrons.

SiO2 gel/alumina-silica fibers composites were prepared by impregnation method. Silicon powder with different mass fractions of 0%, 0.2%, 0.4%, 0.6% and 0.8% was added in the slurry, and the effects of silicon powder on the microstructure, bulk density, compression-resilience ratio and phase compositions of the SiO2 gel/alumina-silica fiber composites were investigated. The results show that when the mass fraction of the silicon powder is lower than 0.6%, the volume expansion of silicon resulting from the silicon oxidation fills the cracks between fibers and gel, the volume density of the composites increases from 0.468g/cm3 to 0.723g/cm3, and the resilience ratios increase from 43.1% to 59.6%. Besides, it is found that the mechanical property is improved and the degree of high-temperature damage for the composites is decreased by the silicon crystallization, which restrains the fibers crystallization and facilitates the generation of pyroxene. However, when the mass fraction of silicon powder is 0.8%,the compression-resilience ratio of the composites significantly declines to 44.5%, which is attributed to the big cracks generated from the excessive volume expansion of silicon powder at high temperature.

Abstract Background Estimation of allele frequency is of fundamental importance in population genetic analyses and in association mapping. In most studies using next-generation sequencing, a cost effective approach is to use medium or low-coverage data (e.g., < 15X). However, SNP calling and allele frequency estimation in such studies is associated with substantial statistical uncertainty because of varying coverage and high error rates. Results We evaluate a new maximum likelihood method for estimating allele frequencies in low and medium coverage next-generation sequencing data. The method is based on integrating over uncertainty in the data for each individual rather than first calling genotypes. This method can be applied to directly test for associations in case/control studies. We use simulations to compare the likelihood method to methods based on genotype calling, and show that the likelihood method outperforms the genotype calling methods in terms of: (1) accuracy of allele frequency estimation, (2) accuracy of the estimation of the distribution of allele frequencies across neutrally evolving sites, and (3) statistical power in association mapping studies. Using real re-sequencing data from 200 individuals obtained from an exon-capture experiment, we show that the patterns observed in the simulations are also found in real data. Conclusions Overall, our results suggest that association mapping and estimation of allele frequencies should not be based on genotype calling in low to medium coverage data. Furthermore, if genotype calling methods are used, it is usually better not to filter genotypes based on the call confidence score.

Abstract Background MicroRNAs(miRNAs) are 18-25 nt small RNAs playing critical roles in many biological processes. The majority of known miRNAs were discovered by conventional cloning and a Sanger sequencing approach. The next-generation sequencing (NGS) technologies enable in-depth characterization of the global repertoire of miRNAs, and different protocols for miRNA library construction have been developed. However, the possible bias between the relative expression levels and sequences introduced by different protocols of library preparation have rarely been explored. Results We assessed three different miRNA library preparation protocols, SOLiD, Illumina versions 1 and 1.5, using cloning or SBS sequencing of total RNA samples extracted from skeletal muscles from Hu sheep and Dorper sheep, and then validated 9 miRNAs by qRT-PCR. Our results show that SBS sequencing data highly correlate with Illumina cloning data. The SOLiD data, when compared to Illumina's, indicate more dispersed distribution of length, higher frequency variation for nucleotides near the 3'- and 5'-ends, higher frequency occurrence for reads containing end secondary structure (ESS), and higher frequency for reads that do not map to known miRNAs. qRT-PCR results showed the best correlation with SOLiD cloning data. Fold difference of Hu sheep and Dorper sheep between qRT-PCR result and SBS sequencing data correlated well (r = 0.937), and fold difference of miR-1 and miR-206 among SOLiD cloning data, qRT-PCR and SBS sequencing data was similar. Conclusions The sequencing depth can influence the quantitative measurement of miRNA abundance, but the discrepancy caused by it was not statistically significant as high correlation was observed between Illumina cloning and SBS sequencing data. Bias of length distribution, sequence variation, and ESS was observed between data obtained with the different protocols. SOLiD cloning data differ from Illumina cloning data mainly because of distinct methods of adapter ligation. The good correlation between qRT-PCR result and SOLiD data might be due to the similarities of the hybridization-based methods. The fold difference analysis indicated that methods based on hybridization may be superior for quantitative measurement of miRNA abundance. Because of the genome sequence of the sheep is not available, our data may not explain how the entire miRNA bias in the natural miRNAs in sheep or other mammal miRNA expression, unbiased artificially synthesized miRNA will help on evaluating the methodology of miRNA library preparation.

Abstract Background Spermatogenesis is a complex process involving cell development, differentiation and apoptosis. This process is governed by a series of genes whose expressions are highly regulated. Male infertility can be attributed to multiple genetic defects or alterations that are related to spermatogenesis. The discovery, cloning and further functional study of genes related to spermatogenesis is of great importance to the elucidation of the molecular mechanism of spermatogenesis. It is also physiologically and pathologically significant to the therapy of male infertility. Methods GON-SJTU1 was identified and cloned from rat testis by cDNA library screening and 3'-and 5'-RACE. The products of GON-SJTU1 were assessed by Northern and Western blotting. The expression of GON-SJTU1 was also examined by In situ hybridization and immunohistochemistry. Results Here we identified and cloned a new gene, GON-SJTU1, with the biological process of spermatogenesis. GON-SJTU1 is highly expressed in the testis from day 1 to 15 and then decreased, suggesting that GON-SJTU1 might be a time-related gene and involved in the early stage of spermatogenesis. And the expression of GON-SJTU1 in the testis occurred in some male germ cells, particularly in gonocytes and spermatogonial stem cells. Conclusion GON-SJTU1 may play a role in the biological process of spermatogenesis.

Abstract Background DNA methylation is a widely studied epigenetic mechanism known to correlate with gene repression and genomic stability. Development of sensitive methods for global detection of DNA methylation events is of particular importance. Results We here describe a technique, called modified methylation-specific digital karyotyping (MMSDK) based on methylation-specific digital karyotyping (MSDK) with a novel sequencing approach. Briefly, after a tandem digestion of genomic DNA with a methylation-sensitive mapping enzyme and a fragmenting enzyme, short sequence tags are obtained. These tags are amplified, followed by direct, massively parallel sequencing (Solexa 1G Genome Analyzer). This method allows high-throughput and low-cost genome-wide DNA methylation mapping. We applied this method to investigate global DNA methylation profiles for widely used breast cancer cell lines, MCF-7 and MDA-MB-231, which are representatives for luminal-like and mesenchymal-like cancer types, respectively. By comparison, a highly similar overall DNA methylation pattern was revealed for the two cell lines. However a cohort of individual genomic loci with significantly different DNA methylation status between two cell lines was identified. Furthermore, we revealed a genome-wide significant correlation between gene expression and the methylation status of gene promoters with CpG islands (CGIs) in the two cancer cell lines, and a correlation of gene expression and the methylation status of promoters without CGIs in MCF-7 cells. Conclusion The MMSDK method will be a valuable tool to increase the current knowledge of genome wide DNA methylation profiles.