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Threose nucleic acid (TNA) is considered a potential RNA progenitor due to its chemical simplicity, base pairing property, and capability of folding into a functional tertiary structure. However, it is unknown whether the functional property can be maintained during transition from TNA to RNA. Here, we use a toggle

Bladder cancer is common worldwide, with most patients presenting with nonmuscle invasive disease. Multiple intravesical recurrences lead to reduced quality of life and high costs for patients with this form of bladder cancer. Intravesical chemotherapy aimed at reducing recurrence is the standard-of-care but has significant side effects from nonspecific cytotoxicity to normal urothelium. Importantly, toxicity limits doses that can be administered. Thus, tumor-specific drug targeting could reduce toxicity and enhance effectiveness by allowing higher doses. Here, using cell internalization systematic evolution of ligands by exponential enrichment (SELEX), we identify a novel bladder cancer-specific, chemically modified nucleic acid aptamer that can be preferentially internalized into tumor cells but not normal urothelial cells. The 35-nucleotide B1 aptamer is internalized into bladder cancer cells through clathrin-mediated endocytosis and macropinocytosis. As proof of principle, a B1-guided DNA nanotrain delivery vehicle for epirubicin was constructed as a targeted intravesical chemotherapy. The B1-nanotrain-epirubicin construct exhibited selective cytotoxicity towards bladder cancer cells and outperformed epirubicin in murine orthotopic xenograft models of human bladder cancer. This aptamer-based delivery system makes targeted chemotherapy possible for bladder cancer, providing a compelling rationale for clinical development.Significance:These findings identify a bladder cancer–specific aptamer that can be used for targeted delivery of chemotherapy, potentially reducing toxicity and enhancing therapeutic efficacy.

Supplementary Data from Development of Novel Aptamer-Based Targeted Chemotherapy for Bladder Cancer

We developed a T-cell-receptor (TCR) complex-based chimeric antigen receptor (CAR) named Synthetic TCR and Antigen Receptor (STAR). Here, we report pre-clinical and phase I clinical trial data (NCT03953599) of this T-cell therapy for refractory and relapsed (R/R) B-cell acute lymphoblastic leukemia (B-ALL) patients. STAR consists of two protein modules each containing an antibody light or heavy chain variable region and TCR α or β chain constant region fused to the co-stimulatory domain of OX40. T-cells were transduced with a STAR-OX40 lentiviral vector. A leukemia xenograft mouse model was used to assess the STAR/STAR-OX40 T cell antitumor activity. Eighteen patients with R/R B-ALL were enrolled into the clinical trial. In a xenograft mouse model, STAR-T-cells exhibited superior tumor-specific cytotoxicity compared with conventional CAR-T cells. Incorporating OX40 into STAR further improved the proliferation and persistence of tumor-targeting T-cells. In our clinical trial, 100% of patients achieved complete remission 4 weeks post-STAR-OX40 T-cell infusion and 16/18 (88.9%) patients pursued consolidative allogeneic hematopoietic stem cell transplantation (allo-HSCT). Twelve of 16 patients (75%) remained leukemia-free after a median follow-up of 545 (433-665) days. The two patients without consolidative allo-HSCT relapsed on Day 58 and Day 186. Mild cytokine release syndrome occurred in 10/18 (55.6%) patients, and 2 patients experienced grade III neurotoxicity. Our preclinical studies demonstrate super anti-tumor potency of STAR-OX40 T-cells compared with conventional CAR-T cells. The first-in-human clinical trial shows that STAR-OX40 T-cells are tolerable and an effective therapeutic platform for treating R/R B-ALL.

DNA can catalyse alternative RNA splicing reactions in vitro, and modulate RNA structure and function.

Enzymatic protein ligation has become the most powerful and widely used method for high-precision atomic force microscopy-based single-molecule force spectroscopy (AFM-SMFS) study of protein mechanics.

Catalytic DNA-based fluorescent sensors have enabled cellular imaging of metal ions such as Mg2+. However, natural DNA is prone to nuclease-mediated degradation. Here we report the in vitro selection of threose nucleic acid (TNA) enzymes with RNA endonuclease activities. One such TNA enzyme, T17-22, catalyzes a site-specific RNA cleavage reaction with a kcat of 0.017 min-1 and KM of 675 nM. A fluorescent sensor based on T17-22 responds to increasing concentration of Mg2+ with a limit of detection at 0.35 mM. This TNA enzyme-based sensor also allows cellular imaging of Mg2+. This work presents the first proof-of-concept demonstration of using a TNA catalyst in cellular metal ion imaging.

DNA nanostructures possess unique programmability and addressability and exhibit a wide variety of potential applications. Recently, they demonstrated their ability to be ideal carriers of antibacterial drugs. In this study, the first use of a DNA six-helix bundle (6HB) nanostructure to co-deliver antisense oligonucleotide (ASO) and silver ions is reported. Although 6HB with Ag+ shows excellent antibacterial effect against both Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus, 6HB with ASO selectively inhibits S. aureus. Furthermore, 6HB with both Ag+ and ASO exhibits enhanced antibacterial efficacy on S. aureus, probably through two sequential activities. Specifically, Ag+-modified 6HB greatly delays bacterial growth by destroying its cell walls, whereas 6HB conjugated with ASO targeting the ftsZ gene of S. aureus effectively inhibits its growth in the logarithmic growth phase by inhibiting the expression of the ftsZ gene. Moreover, this synergistic antibacterial treatment shows excellent biosafety with human normal liver cell L02. This co-delivery system by DNA nanostructures provides a promising platform for antibacterial therapeutics.

Background To compare the corneal deformation response between patients with keratoconus and healthy subjects and to identify potential characteristics associated with corneal response parameters. Methods This case-control study included a total of 40 keratoconus patients (40 eyes) and 40 age- and sex-matched healthy subjects (40 eyes) whose central corneal thickness (CCT) was less than 500 µm. Pentacam HR and Corvis ST were used to measure the corneal topographies and the corneal deformation response parameters. Results No significant difference was found in the age, sex, laterality distribution, IOP, and CCT between the keratoconus group and healthy controls. The keratoconus eyes had smaller TCT than the healthy controls (p

Bladder cancer is common worldwide, with most patients presenting with nonmuscle invasive disease. Multiple intravesical recurrences lead to reduced quality of life and high costs for patients with this form of bladder cancer. Intravesical chemotherapy aimed at reducing recurrence is the standard-of-care but has significant side effects from nonspecific cytotoxicity to normal urothelium. Importantly, toxicity limits doses that can be administered. Thus, tumor-specific drug targeting could reduce toxicity and enhance effectiveness by allowing higher doses. Here, using cell internalization systematic evolution of ligands by exponential enrichment (SELEX), we identify a novel bladder cancer-specific, chemically modified nucleic acid aptamer that can be preferentially internalized into tumor cells but not normal urothelial cells. The 35-nucleotide B1 aptamer is internalized into bladder cancer cells through clathrin-mediated endocytosis and macropinocytosis. As proof of principle, a B1-guided DNA nanotrain delivery vehicle for epirubicin was constructed as a targeted intravesical chemotherapy. The B1-nanotrain-epirubicin construct exhibited selective cytotoxicity towards bladder cancer cells and outperformed epirubicin in murine orthotopic xenograft models of human bladder cancer. This aptamer-based delivery system makes targeted chemotherapy possible for bladder cancer, providing a compelling rationale for clinical development. Significance: These findings identify a bladder cancer–specific aptamer that can be used for targeted delivery of chemotherapy, potentially reducing toxicity and enhancing therapeutic efficacy.

DNA nanotechnology is powerful in constructing programmable nanostructures with distinct dimensions, sizes, and shapes. However, natural DNA molecules are prone to nuclease degradation, thus limiting the in vivo applications of such DNA nanostructures. 2'-Fluoroarabinonucleic acid (FANA) is a chemically modified oligonucleotide with similar base pairing properties to DNA and exhibits superior physical and chemical stabilities. In this work, FANA molecules were used to construct double crossover nanostructures, and it was demonstrated that incorporation of FANA conferred nucleic acid nanostructures with increased thermal stability and stronger nuclease resistance. More importantly, FANA nanostructures were able to maintain the structural integrity in the strongly acidic environment (pH 1.2). Last, such FANA nanostructures functioned well in acting as stable carriers of small-molecule cargoes for cellular delivery in simulated gastric fluid, while the DNA counterparts were mostly degraded. Collectively, these results demonstrated that FANA self-assembly was not only a substantial complement to the structural DNA nanotechnology but also an appealing molecular tool for in vivo biomedical applications.

PURPOSE: To evaluate the potential effect of age and refractive error on visual acuity (VA) performance and quick contrast sensitivity function (qCSF) in normal Chinese adults. METHOD: Ninety-two subjects with normal best corrected distance VA (BCDVA) were enrolled in this pilot study. Measurements included BCDVA, best corrected near VA (BCNVA), unaided VA (UNVA), habitual spectacle-corrected near VA (SCNVA) and qCSF. For analyses, subjects were categorized into three age groups (20~40 years, 41~60 year and >60 years) and four refractive groups (hyperopia, emmetropia, myopia and high myopia). Relationships between age, refractive error, types of VA and qCSF were tested using simple and multiple linear regressions analyses. RESULT: Mean age and refractive error of the study participants were 44.04 ± 12.68 years and −1.86 ± 2.91D, respectively. Among the stratified age groups, a hyperopic shift of refraction (−3.24 ± 2.88D vs. −1.24 ± 2.64D vs. 0.39 ± 1.42D, respectively; P

Precise surface functionalization and reconfigurable capability of nanomaterials are essential to construct complex nanostructures with specific functions. Here we show the assembly of a reconfigurable plasmonic nanostructure, which executes both conformational and plasmonic changes in response to DNA strands. In this work, different sized gold nanoparticles(AuNPs) were arranged site-specifically on the surface of a DNA origami clamp nanostructure. The opening and closing of the DNA origami clamp could be precisely controlled by a series of strand displacement reactions. Therefore, the patterns of these AuNPs could be switched between two different configurations. The observed plasmon band shift indicates the change of the plasmonic interactions among the assembled AuNPs. Our study achieves the construction of reconfigurable nanomaterials with tunable plasmonic interactions, and will enrich the toolbox of DNA-based functional nanomachinery.

Purpose. The purpose of this study was to evaluate the long-term prognosis of small-incision femtosecond laser-assisted intracorneal concave lenticule implantation (SFII) in correction of human keratoconus. Methods. This was a prospective study for 11 patients who received SFII after being diagnosed as progressive keratoconus based on the Amsler–Krumeich classification system. Clinical assessment was performed for all the patients prior to and postsurgically at different time points for 5 years. These included uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), biomechanically corrected intraocular pressure (bIOP), corneal topography, anterior segment optical coherence tomography (AS-OCT), confocal microscopy, and biomechanical assessment with Corvis ST. Results. Comparison of preoperative and 60-month postoperative UDVA and CDVA ( P 60 months = 0.081 and 0.001, respectively), all eyes showed an improvement in CDVA. Corneal topography showed no significant changes in corneal anterior K1, K2, posterior K1, K2, posterior elevation, or corneal densitometry compared with preoperative levels ( P > 0.05 ). Corvis ST showed that central corneal thickness (CCT) and stiffness at applanation 1 (SP-A1) were significantly greater 1 week postsurgically when compared to the baseline ( P < 0.05 ) and remained stable thereafter. The lenticule under the AS-OCT remained transparent throughout the entire postsurgical period. Under confocal microscopy, corneal edema and an increase in cell activation and reflectivity were observed at the lenticule-stromal interface within 1 week postoperatively. These reactions gradually subsided with time within 6 months. Conclusion. SFII is an effective procedure to prevent the progression of keratoconus due to its minimal invasiveness and capability of maintaining a steady biometry of the cornea.

Background. Pathological neovascularization, which involves a disruption in the balance between angiogenic and antiangiogenic factors under pathological conditions, is the basis of many intraocular diseases. Pigment epithelium-derived factor (PEDF) is a potent natural, endogenous inhibitor of neovascularization because of its antiangiogenic and neuroprotective benefits. However, its application is restricted by its instability and short half-life. The present study is aimed at investigating the cytotoxicity and antiangiogenic effects of PEDF-loaded PEGylated nanoparticles (NP-PEG-PEDF) on high glucose-stimulated human umbilical vein endothelial cells (HUVECs). Methods. In this study, NP-PEG-PEDF were fabricated using the multiple emulsion method for the first time. HUVECs were cultured in a high concentration of glucose (30 mmol/L D-glucose), simulating diabetic conditions. The antiangiogenic effects of vascular endothelial growth factor (VEGF), pure PEDF, and NP-PEG-PEDF on proliferation, migration, and tube formation were evaluated. VEGF secretion in high glucose-stimulated HUVECs was further tested in vitro. Results. NP-PEG-PEDF exhibited low cytotoxicity in HUVECs. Our results indicated that in vitro, NP-PEG-PEDF attenuated diabetes-induced HUVEC proliferation, migration, and tube formation and suppressed VEGF secretion. The apoptosis of diabetes-induced HUVECs occurred in a dose-dependent manner, which showed a statistically significant difference compared with the PEDF treatment group. Conclusion. Our study is the first to demonstrate that NP-PEG-PEDF exert antiangiogenic effects on high glucose-stimulated HUVECs and have the potential to alleviate microvascular dysfunction. These data suggest that the NP-PEG-PEDF delivery system may offer an innovative therapeutic strategy for preventing neovascularization of the fundus.

The manufacture of DNA origami nanostructures with highly ordered functional motifs is of great significance for biomedical applications. Here, we present a robust strategy to produce customized scaffolds with integrated aptamer sequences, which enables direct construction of functional DNA origami structures. As we demonstrated, aptamers of various numbers and types were efficiently and stably integrated in user-defined positions of the scaffolds. Specifically, two different thrombin aptamer sequences were simultaneously inserted into the M13mp18 phage genome. The assembled functional DNA origami structures from this aptamer-integrated scaffold exhibited increased binding efficiency to thrombin and displayed more than 10-fold stronger resistance to exonuclease degradation than that produced using the traditional staple extension method. Additionally, a scaffold integrated with the platelet-derived growth factor aptamer was produced, and the assembled DNA origami structures showed significant inhibitory effect on breast cancer cells MDA-MB-231. This scalable method of creating design-specific scaffolds opens up a new way to construct more stable and functionally robust DNA origami structures and thus provides an important basis for their broader applications.

The first demonstration of direct sequencing of 2′-deoxy-2′-fluoroarabinonucleic acid (FANA) using Nanopore-Induced Phase-Shift Sequencing (NIPSS)., 2′-deoxy-2′-fluoroarabinonucleic acid (FANA), which is one type of xeno-nucleic acid (XNA), has been intensively studied in molecular medicine and synthetic biology because of its superior gene-silencing and catalytic activities. Although urgently required, FANA cannot be directly sequenced by any existing platform. Nanopore sequencing, which identifies a single molecule analyte directly from its physical and chemical properties, shows promise for direct XNA sequencing. As a proof of concept, different FANA homopolymers show well-distinguished pore blockage signals in a Mycobacterium smegmatis porin A (MspA) nanopore. By ligating FANA with a DNA drive-strand, direct FANA sequencing has been demonstrated using phi29 DNA polymerase by Nanopore-Induced Phase Shift Sequencing (NIPSS). When bound with an FANA template, the phi29 DNA polymerase shows unexpected reverse transcriptase activity when monitored in a single molecule assay. Following further investigations into the ensemble, phi29 DNA polymerase is shown to be a previously unknown reverse transcriptase for FANA that operates at room temperature, and is potentially ideal for nanopore sequencing. These results represent the first direct sequencing of a sugar-modified XNA and suggest that phi29 DNA polymerase could act as a promising enzyme for sustained sequencing of a wide variety of XNAs.

Purpose: We investigated ocular accommodative responses and pupil diameters under different light intensities in order to explore whether changes in light intensity aid effective accommodation function training. Methods:A total of 29 emmetropic and myopic subjects (age range: 12–18 years) viewed a target in dynamic ambient light (luminance: 5, 100, 200, 500, 1000, 2000 and 3000 lux) and static ambient light (luminance: 1000 lux) at a 40 cm distance with refractive correction. Accommodation and pupil diameter were recorded using an open-field infrared autorefractor and an ultrasound biological microscope, respectively. Results: The changes in the amplitude of accommodative response and pupil diameter under dynamic lighting were 1.01 ± 0.53 D and 2.80 ± 0.75 mm, respectively, whereas in static lighting, those values were 0.43 ± 0.24 D and 0.77 ± 0.27 mm, respectively. The amplitude of accommodation and pupil diameter change in dynamic lighting (t = 6.097, p < 0.001) was significantly larger than that under static lighting (t = 16.115, p < 0.001).The effects of light level on both accommodation and pupil diameter were significant (p < 0.001). Conclusion: Accommodation was positively correlated with light intensity. The difference was about 1.0 D in the range of 0–3000 lux, which may lay the foundation for accommodative training through light intervention.

Near work has been considered to be a potential risk factor for the onset of myopia, but with inadequate evidence. Chinese adolescents use digital devices for near work, such as study and entertainment purposes, especially during the COVID-19 pandemic. In this study, we investigated the influence of prolonged periods of near work on accommodative response, accommodative microfluctuations (AMFs), and pupil diameter between juvenile subjects of myopia and emmetropia. Sixty juveniles (30 myopes and 30 emmetropes) were recruited for the study. Participants were instructed to play a video game on a tablet PC at a distance of 33.3 cm for 40 min. Accommodative response and pupil diameter were measured with an open-field infrared refractometer in High-speed mode. Parameters of the subjects were measured once every 10 min, and analyzed by one-way repeated measure ANOVA for variation tendency. There were no significant differences between emmetropia and myopia groups with respect to age and sex (p > 0.05). The low-frequency component (LFC) of myopia gradually increased with time, reached a peak at 30 min, and then declined (p = 0.043). The high-frequency component (HFC) of myopia also reached a peak at 30 min (p = 0.036). Nevertheless, there was no significant difference in the LFC (p = 0.171) or HFC (p = 0.278) of the emmetropia group at each time point. There was no significant difference in the mean and standard deviation of the accommodative response and pupil diameter both in emmetropic and myopic juveniles. Compared with juvenile emmetropes, myopes exhibit an unstable tendency in their accommodation system for prolonged near work at a certain time point. Accommodative microfluctuations may be a sensitive, objective indicator of fatigue under sustained near work in juvenile myopes.

Threose nucleic acid (TNA) has been considered a potential RNA progenitor in evolution due to its chemical simplicity and base pairing property. Catalytic TNA sequences with RNA ligase activities might have facilitated the transition to the RNA world. Here we report the isolation of RNA ligase TNA enzymes by in vitro selection. The identified TNA enzyme T8-6 catalyzes the formation of a 2'-5' phosphoester bond between a 2',3'-diol and a 5'-triphosphate group, with a kobs of 1.1 × 10-2 min-1 (40 mM Mg2+, pH 9.0). For efficient reaction, T8-6 requires UA|GA at the ligation junction and tolerates variations at other substrate positions. Functional RNAs such as hammerhead ribozyme can be prepared by T8-6-catalyzed ligation, with site-specific introduction of a 2'-5' linkage. Together, this work provides experimental support for TNA as a plausible pre-RNA genetic polymer and also offers an alternative molecular tool for biotechnology.

Threose nucleic acid (TNA) aptamers were selected in vitro to bind PD-L1 protein and inhibit its interaction with PD-1. These biologically stable TNA aptamers bound target proteins with nanomolar affinities, and effectively blocked PD-1/PD-L1 interaction in vitro. After injection into a colon cancer xenograft mouse model, the TNA aptamer N5 was specifically accumulated at the tumour site, and significantly inhibited tumour growth in vivo.

Cisplatin and oxaliplatin are widely used anti-tumour chemotherapeutic agents with different spectra of activity. The therapeutic efficacy of such platinum-based drug is believed to, at least in part, result from formation of Pt–DNA adducts, followed by DNA damage response and ultimately apoptosis. However, it remains unclear whether these DNA lesions caused by cisplatin and oxaliplatin elicit distinct reactions in cellular signaling pathways. Here, a label-free comparative proteomic study was performed to profile the protein phosphorylation patterns using Pt–DNA probes with different ligand identities and geometries. Phosphorylated proteins recognizing different cisplatin- and oxaliplatin–DNA lesions were enriched and analyzed on LC-MS/MS. Proteomic analysis revealed that cisplatin mainly affected proteins involved in mRNA processing, while chromatin organization and rRNA processing are two major biological processes influenced by oxaliplatin. Changes to site-specific phosphorylation levels of two proteins YBX1 and UBF1 were also validated by Western blotting. In particular, platinum drug treatment in colon and liver cancer cell lines down-regulated S484 phosphorylation of UBF1, which is an essential transcription factor responsible for ribosomal DNA transcription activation, implying that inhibition of ribosome biogenesis might be involved in the cytotoxic mechanism of platinum drugs. Collectively, these results directly reflected distinct protein phosphorylation patterns triggered by cisplatin and oxaliplatin, and could also provide valuable resources for future mechanistic studies of platinum-based anti-tumour agents.

Threose nucleic acid has been considered a potential evolutionary progenitor of RNA because of its chemical simplicity, base pairing properties and capacity for higher-order functions such as folding and specific ligand binding. Here we report the in vitro selection of RNA-cleaving threose nucleic acid enzymes. One such enzyme, Tz1, catalyses a site-specific RNA-cleavage reaction with an observed pseudo first-order rate constant (k

Deoxyribozymes capable of catalyzing sequence-specific RNA cleavage have broad applications in biotechnology. In vitro selected RNA-cleaving deoxyribozymes normally contain two substrate-binding arms and a central catalytic core region. Here, we describe the systematic characterization and optimization of an RNA-cleaving deoxyribozyme with an unusually short left binding arm, and its special sequence requirement for its optimal catalytic activity.

Deoxyribozymes capable of catalyzing sequence-specific RNA cleavage have broad applications in biotechnology. In vitro selected RNA-cleaving deoxyribozymes normally contain two substrate-binding arms and a central catalytic core region. Here, we describe the systematic characterization and optimization of an RNA-cleaving deoxyribozyme with an unusually short left binding arm, and its special sequence requirement for its optimal catalytic activity.

This paper presents a hybrid seven-level converter based on T-type converter and H-bridge cascaded suitable for low-voltage and high-power-density applications. The operation principles and conduction paths are analyzed comprehensively. Voltage balance control of the floating capacitors is the key point of this paper. Mathematical expressions of capacitor voltage balance conditions are deduced based on sinusoidal pulse width modulation (SPWM). The results show that floating capacitor voltages are only balanced when the modulation index is below 0.82 under SPWM. In order to enlarge the modulation index ensuring the capacitor voltage balance, space vector modulation (SVM) is also applied to regulate floating capacitor voltages taking advantage of redundant switching vectors. Meanwhile, in SVM, there are no additional control requirements for the capacitor voltage. Taken both SPWM and SVM into consideration, the limit to the range of operation for this seven-level converter is presented, which is a function of the modulation index and the power factor. The merit of dc voltage utilization improvement in this topology is also analyzed based on simulation results. Simulations and experimental results under different modulation index and RL load are presented to verify the modulation strategies illustrated in this paper.

A modified four-point bending test was conducted on air-plasma sprayed (APS) thermal barrier coatings (TBC) to investigate the impact of bond coat (BC) topography tortuosity on the TBC fracture mechanics. The degree of BC tortuosity was quantified by the novel total thresholded summit area surface descriptor (Ssth) and was found to influence the crack path configuration, critical energy release rate (Gc) and crack propagation velocity (νprop). Specimens with higher BC interface tortuosity and more compliant TBC microstructures displayed a reduced strain energy release rates (Gc ≤ 79.90 J. m−2) and crack propagation velocities (vprop ≤ 0.90 mm. s−1). Delamination was primarily governed by the degree of inter-splat cohesion and intra-splat segmentation, although the topography-induced inter-splat tortuosity still had a relevant impact on fracture mechanics. The correlation observed between these results and the lifetime of analogous thermally cycled specimens tested herein suggests that the BC interface can affect the effectiveness of the microstructural stress relaxation mechanisms and by extension the TBC durability.

Procalcitonin (PCT) has emerged as a new prognostic inflammatory marker in a variety of diseases. This study aimed to evaluate whether PCT is associated with increased risk of unfavorable outcome in intracerebral hemorrhage (ICH) patients. During January 2015–December 2016, we conducted a prospective cohort investigation involved 251 primary ICH patients who were admitted within 24 h after the onset of symptoms. We assessed serum PCT levels for all patients at admission. The functional outcome after 3 months was evaluated by modified Rankin Scale (mRS) and dichotomized as favorable (mRS 0–2) and unfavorable (mRS 3–6). The independent risk factors for unfavorable outcome and mortality after 3 months were examined by binary logistic regression. Of 251 ICH patients, the median PCT concentration was 0.053 µg/L (interquartile range 0.035–0.078 µg/L). Unfavorable outcome and mortality at 3 months were observed in 161 (64.1%) and 51 (20.3%) patients, respectively. After adjusting for potential confounders, patients with PCT levels in the top quartile (>0.078 ug/L), compared with the lowest quartile (

Deoxyribozymes capable of catalyzing sequence-specific RNA cleavage have found broad applications in biotechnology, DNA computing and environmental sensing. Among these, deoxyribozyme 8–17 is the most common small DNA motif capable of catalyzing RNA cleavage. However, the extent to which other DNA molecules with similar catalytic motifs exist remains elusive. Here we report a novel RNA-cleaving deoxyribozyme called 10–12opt that functions with an equally small catalytic motif and an unusually short binding arm. This deoxyribozyme contains a 14-nucleotide catalytic core that preferentially catalyzes RNA cleavage at UN dinucleotide junctions (kobs = 0.9 h−1 for UU cleavage). Surprisingly, the left binding arm contains only three nucleotides and forms two canonical base pairs with the RNA substrate. Mutational analysis reveals that a riboguanosine residue 3-nucleotide downstream of cleavage site must not form canonical base pairing for the optimal catalysis, and this nucleobase likely participates in catalysis with its carbonyl O6 atom. Furthermore, we demonstrate that deoxyribozyme 10–12opt can be utilized to cleave certain microRNA sequences which are not preferentially cleaved by 8–17. Together, these results suggest that this novel RNA-cleaving deoxyribozyme forms a distinct catalytic structure than 8–17 and that sequence space may contain additional examples of DNA molecules that can cleave RNA at site-specific locations.

As a milestone in DNA self-assembly, DNA origami has demonstrated powerful applications in many fields. However, the scarce availability of long single-stranded DNA (ssDNA) limits the size and sequences of DNA origami nanostructures, which in turn impedes the further development. In this study, we present a robust strategy to produce long circular ssDNA scaffold strands with custom-tailored lengths and sequences. These ssDNA products were then used as scaffolds for constructing various DNA origami nanostructures. This scalable method produces ssDNA at low cost with high purity and high yield, which can enable production of custom-designed DNA origami for various applications.

Three-stage energy router is the most popular design scheme for energy router. Many high-frequency transformers exist in this structure but how to reduce their volume is a difficult problem. A modified high-frequency transformer structure is introduced in this paper which is beneficial to compression volume. Cascaded H-Bridge topology is usually served as a rectifier in the three-stage energy router. Due to the inherent problem of capacitor voltage balance among each module in this topology, the so called working mode exchange scheme is always employed to regulate capacitor voltages. However, the conventional exchange scheme brings a tremendous amount of computing and ignores the problem of extra device action times during the execution process which can increase switching losses. A modified working mode exchange strategy is presented in this paper. It can reduce the amount of computation and decrease extra device action times at the same time. The proposed strategy only changes the working mode for the largest voltage and smallest voltage module. It reduces the mode exchange frequency and then decreases the possibility of extra action times appearing. Finally, the validity of the modified transformer structure and improved strategy is confirmed by simulation results on a 2MW three-stage energy router.

In order to solve the inherent problem of ‘even power distribution’ or ‘dc-link capacitor voltage balance’ in the cascaded H-Bridge topology, the so called drive signal exchange scheme is always employed. However, the conventional exchange scheme ignores the problem of extra switching during the execution process which increases switching losses. The cause of switching cost increase during exchange process is deeply analyzed in this paper. In order to solve this problem, taking all kinds of potential exchange cases into consideration, this paper proposes an improved strategy which can eliminate extra switching totally. This algorithm makes a full use of the natural PWM action and optimize the exchange procedure to realize the switching states exchange. Finally, the validity and effectiveness of the proposed strategy is confirmed by several experimental tests on a seven-level cascaded H-bridge system.

A modified hybrid multilevel converter which is a combination of T-type converter and H-bridge is present in this paper. Beside increase output levels, another merit of this topology is larger output range compared with traditional two-level converter. Depending on the value of H-bridge floating capacitor voltage, the converter can produce 5-level, 7-level, or 9-level output voltage. The H-bridge floating capacitor voltage stability conditions are deduced based on sinusoidal pulse width modulation (SPWM) for 9-level output voltage levels. The maximum output range under SPWM of different output voltage levels is analyzed in this paper. The feasibility of capacitor voltage balance conditions is verified by simulations. Experiment results are given when 5-level voltage outputs.

This paper presents a modified five-level hybrid converter which based on a T-type converter (T2C) with H-bridge (HB) cell. The considered converter, which is referred to as T2C-HB, utilizes merits of T2C converter and cascade H-bridge converter while avoids their disadvantages. It has high efficiency advantage over NPC in low voltage applications and doesn't need extra isolated power to supply HB part. A larger range of output voltage can be achieved based on sinusoidal pulse width modulation (SPWM). The conduction paths and H-bridge dc-link capacitors balance conditions are well analyzed in this paper. A proposed switching sequence is designed based on three principles of balancing capacitors voltage, no unwanted voltage jump appearing in the dead-time period and minimum switching losses. The validity of the modified converter, modulation strategy and switching sequence is verified by simulation and experiment results.