mDia formins form hetero-oligomers and cooperatively maintain murine hematopoiesis.

mDia formin proteins regulate the dynamics and organization of the cytoskeleton through their linear actin nucleation and polymerization activities. We previously showed that mDia1 deficiency leads to aberrant innate immune activation and induces myelodysplasia in a mouse model, and mDia2 regulates enucleation and cytokinesis of erythroblasts and the engraftment of hematopoietic stem and progenitor cells (HSPCs). However, whether and how mDia formins interplay and regulate hematopoiesis under physiological and stress conditions remains unknown. Here, we found that both mDia1 and mDia2 are required for HSPC regeneration under stress, such as serial plating, aging, and reconstitution after myeloid ablation. We showed that mDia1 and mDia2 form hetero-oligomers through the interactions between mDia1 GBD-DID and mDia2 DAD domains. Double knockout of mDia1 and mDia2 in hematopoietic cells synergistically impaired the filamentous actin network and serum response factor-involved transcriptional signaling, which led to declined HSPCs, severe anemia, and significant mortality in neonates and newborn mice. Our data demonstrate the potential roles of mDia hetero-oligomerization and their non-rodent functions in the regulation of HSPCs activity and orchestration of hematopoiesis.

Initial Amino Acid:Codon Assignments and Strength of Codon:Anticodon Binding.

The ribosome brings 3'-aminoacyl-tRNA and 3'-peptidyl-tRNAs together to enable peptidyl transfer by binding them in two major ways. First, their anticodon loops are bound to mRNA, itself anchored at the ribosomal subunit interface, by contiguous anticodon:codon pairing augmented by interactions with the decoding center of the small ribosomal subunit. Second, their acceptor stems are bound by the peptidyl transferase center, which aligns the 3'-aminoacyl- and 3'-peptidyl-termini for optimal interaction of the nucleophilic amino group and electrophilic ester carbonyl group. Reasoning that intrinsic codon:anticodon binding might have been a major contributor to bringing tRNA 3'-termini into proximity at an early stage of ribosomal peptide synthesis, we wondered if primordial amino acids might have been assigned to those codons that bind the corresponding anticodon loops most tightly. By measuring the binding of anticodon stem loops to short oligonucleotides, we determined that family-box codon:anticodon pairings are typically tighter than split-box codon:anticodon pairings. Furthermore, we find that two family-box anticodon stem loops can tightly bind a pair of contiguous codons simultaneously, whereas two split-box anticodon stem loops cannot. The amino acids assigned to family boxes correspond to those accessible by what has been termed cyanosulfidic chemistry, supporting the contention that these limited amino acids might have been the first used in primordial coded peptide synthesis.

Machine Learning-Assisted High-Throughput Identification and Quantification of Protein Biomarkers with Printed Heterochains.

Advanced in vitro diagnosis technologies are highly desirable in early detection, prognosis, and progression monitoring of diseases. Here, we engineer a multiplex protein biosensing strategy based on the tunable liquid confinement self-assembly of multi-material heterochains, which show improved sensitivity, throughput, and accuracy compared to standard ELISA kits. By controlling the material combination and the number of ligand nanoparticles (NPs), we observe robust near-field enhancement as well as both strong electromagnetic resonance in polymer-semiconductor heterochains. In particular, their optical signals show a linear response to the coordination number of the semiconductor NPs in a wide range. Accordingly, a visible nanophotonic biosensor is developed by functionalizing antibodies on central polymer chains that can identify target proteins attached to semiconductor NPs. This allows for the specific detection of multiple protein biomarkers from healthy people and pancreatic cancer patients in one step with an ultralow detection limit (1 pg/mL). Furthermore, rapid and high-throughput quantification of protein expression levels in diverse clinical samples such as buffer, urine, and serum is achieved by combining a neural network algorithm, with an average accuracy of 97.3%. This work demonstrates that the heterochain-based biosensor is an exemplary candidate for constructing next-generation diagnostic tools and suitable for many clinical settings.

Monitoring trends in the absolute lymphocyte count and the neutrophil-to-lymphocyte ratio in patients with breast cancer receiving eribulin.

BACKGROUND: Studies have shown that the absolute lymphocyte count (ALC) and the neutrophil-to-lymphocyte ratio (NLR) are related to the outcomes in patients with breast cancer receiving specific chemotherapies. However, the reports have focussed on the initial blood test and there is a lack of evidence or data to support that dynamic changes of ALC or NLR are associated with the patients' survival outcomes. METHODS: We retrospectively reviewed electronic medical records from patients with breast cancer treated with eribulin from 2015 to 2019 at our institution. Blood test data were available prior to starting eribulin (baseline), and at 1, 3 and 6 months after initiating eribulin. We classified the patients into ALC and NLR high and low groups using the following cut-offs: 1000/µl for ALC and 3 for NLR. We defined ALC and NLR trends as increasing or decreasing compared with the initial data. We assessed the associations between the ALC and NLR with progression-free survival and overall survival. RESULTS: There were 136 patients with breast cancer treated with eribulin. Of these patients, 60 had complete blood tests and follow-up data. Neither a high ALC nor a low baseline NLR was associated with the survival outcome. One month after initiating eribulin treatment, a high ALC and a low NLR were significantly associated with longer progression-free survival (p = 0.044 for each). Three months after initiating eribulin, a high ALC was significantly associated with better overall survival (p = 0.006). A high NLR at 3 or 6 months after initiating eribulin was associated with worse overall survival (p = 0.017 and p = 0.001, respectively). The ALC and NLR trends across times were not associated with survivals. CONCLUSION: We showed that 1, 3 and 6 months after initiating eribulin, a high ALC and a low NLR may be related to the patients' survival outcomes. The ALC and NLR trends were not associated with survival. Accordingly, we believe patients who maintain a high ALC and a low NLR may have better clinical outcomes after initiating eribulin.

Photoinduced Decarboxylative Difluoroalkylation and Perfluoroalkylation of α-Fluoroacrylic Acids.

Herein, a novel and practical methodology for the photoinduced decarboxylative difluoroalkylation and perfluoroalkylation of α-fluoroacrylic acids is reported. A wide range of α-fluoroacrylic acids can be used as applicable feedstocks, allowing for rapid access to structurally important difluoroalkylated and polyfluoroalkylated monofluoroalkenes with high Z-stereoselectivity under mild conditions. The protocol demonstrates excellent functional group compatibility and provides a platform for modifying complex biologically active molecules.

Printable Smart Materials and Devices: Strategies and Applications.

Smart materials are a kind of functional materials which can sense and response to environmental conditions or stimuli from optical, electrical, magnetic mechanical, thermal, and chemical signals, etc. Patterning of smart materials is the key to achieving large-scale arrays of functional devices. Over the last decades, printing methods including inkjet printing, template-assisted printing, and 3D printing are extensively investigated and utilized in fabricating intelligent micro/nano devices, as printing strategies allow for constructing multidimensional and multimaterial architectures. Great strides in printable smart materials are opening new possibilities for functional devices to better serve human beings, such as wearable sensors, integrated optoelectronics, artificial neurons, and so on. However, there are still many challenges and drawbacks that need to be overcome in order to achieve the controllable modulation between smart materials and device performance. In this review, we give an overview on printable smart materials, printing strategies, and applications of printed functional devices. In addition, the advantages in actual practices of printing smart materials-based devices are discussed, and the current limitations and future opportunities are proposed. This review aims to summarize the recent progress and provide reference for novel smart materials and printing strategies as well as applications of intelligent devices.

Entropy-Regulated Cathode with Low Strain and Constraint Phase-Change Toward Ultralong-Life Aqueous Al-Ion Batteries.

During multivalent ions insertion processes, intense electrostatic interaction between charge carriers and host makes the high-performance reversible Al3+ storage remains an elusive target. On account of the strong electrostatic repulsion and poor robustness, Prussian Blue analogues (PBAs) suffer severely from the inevitable and large strain and phase change during reversible Al3+ insertion. Herein, we demonstrate an entropy-driven strategy to realize ultralong life aqueous Al-ion batteries (AIBs) based on medium entropy PBAs (ME-PBAs) host. By multiple redox active centers introduction, the intrinsic poor conductivity can be enhanced simultaneously, resulting in outstanding capabilities of electrochemical Al3+ storage. Meanwhile, the co-occupation at metal sites in PBA frameworks can also increase the M-N bond intensity, which is beneficial for constraining the phase change during consecutive Al3+ reversible insertion, to realize an extended lifespan over 10,000 cycles. Based on the calculation at different operation states, the fluctuation of ME-PBA lattice parameters is only 1.2 %. Assembled with MoO3 anodes, the full cells can also deliver outstanding electrochemical properties. The findings highlight that, the entropy regulation strategy could uncover the isochronous constraint on both strain and phase transition for long-term reversible Al3+ storage, providing a promising design for advanced electrode materials for aqueous multivalent ions batteries.

Triplet-Encoded Prebiotic RNA Aminoacylation.

The encoding step of translation involves attachment of amino acids to cognate tRNAs by aminoacyl-tRNA synthetases, themselves the product of coded peptide synthesis. So, the question arises─before these enzymes evolved, how were primordial tRNAs selectively aminoacylated? Here, we demonstrate enzyme-free, sequence-dependent, chemoselective aminoacylation of RNA. We investigated two potentially prebiotic routes to aminoacyl-tRNA acceptor stem-overhang mimics and analyzed those oligonucleotides undergoing the most efficient aminoacylation. Overhang sequences do not significantly influence the chemoselectivity of aminoacylation by either route. For aminoacyl-transfer from a mixed anhydride donor strand, the chemoselectivity and stereoselectivity of aminoacylation depend on the terminal three base pairs of the stem. The results support early suggestions of a second genetic code in the acceptor stem.

Molecular Recognition-Modulated Hetero-Assembly of Nanostructures for Visualizable and Portable Detection of Circulating miRNAs.

Biomolecular markers, particularly circulating microRNAs (miRNAs) play an important role in diagnosis, monitoring, and therapeutic intervention of cancers. However, existing detection strategies remain intricate, laborious, and far from being developed for point-of-care testing. Here, we report a portable colorimetric sensor that utilizes the hetero-assembly of nanostructures driven by base pairing and recognition for direct detection of miRNAs. Following hybridization, two sizes of nanoparticles modified with single-strand DNA can be robustly assembled into heterostructures with strong optical resonance, exhibiting distinct structure colors. Particularly, the large nanoparticles are first arranged into nanochains to enhance scattering signals of small nanoparticles, which allows for sensitive detection and quantification of miRNAs without the requirement of target extraction, amplification, and fluorescent labels. Furthermore, we demonstrate the high specificity and single-base selectivity of testing different miRNA samples, which shows great potential in the diagnosis, staging, and monitoring of cancers. These heterogeneous assembled nanostructures provide an opportunity to develop simple, fast, and convenient tools for miRNAs detection, which is suitable for many scenarios, especially in low-resource setting.

Supramolecular Photonic Hydrogel for High-Sensitivity Alkaline Phosphatase Detection via Synergistic Driving Force.

Structurally-colored photonic hydrogels which are fabricated by introducing hydrogels into thin films or photonic crystal structures are promising candidates for biosensing. Generally, the design of photonic hydrogel biosensors is based on the sensor-analyte interactions induced charge variation within the hydrogel matrix, or chemically grafting binding sites onto the polymer chains, to achieve significant volume change and color variation of the photonic hydrogel. However, relatively low anti-interference capability or complicated synthesis hinder the facile and low-cost fabrication of high-performance photonic hydrogel biosensors. Here, a facilely prepared supramolecular photonic hydrogel biosensor is developed for high-sensitivity detection of alkaline phosphatase (ALP), which is an extensively considered clinical biomarker for a variety of diseases. Responding to ALP results in the broken supramolecular crosslinking and thus increased lattice distancing of the photonic hydrogel driven by synergistic repulsive force between nanoparticles embedded in photonic crystal structure and osmotic swelling pressure. The biosensor shows sensitivity of 7.3 nm spectral shift per mU mL-1 ALP, with detection limit of 0.52 mU mL-1 . High-accuracy colorimetric detection can be realized via a smartphone, promoting point-of-care sensing and timely diagnosis of related pathological conditions.

At-Home COVID-19 Rapid Antigen Test Down to 0.03 pg mL-1 of Nucleocapsid Protein.

Rapid and ultra-sensitive detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is critical for early screening and management of COVID-19. Currently, the real-time reverse transcription polymerase chain reaction (rRT-PCR) is the primary laboratory method for diagnosing SARS-CoV-2. It is not suitable for at-home COVID-19 diagnostic test due to the long operating time, specific equipment, and professional procedures. Here an all-printed photonic crystal (PC) microarray with portable device for at-home COVID-19 rapid antigen test is reported. The fluorescence-enhanced effect of PC amplifies the fluorescence intensity of the labeled probe, achieving detection of nucleocapsid (N-) protein down to 0.03 pg mL-1 . A portable fluorescence intensity measurement instrument gives the result (negative or positive) by the color of the indicator within 5 s after inserting the reacted PC microarray test card. The N protein in inactivated virus samples (with cycle threshold values of 26.6-40.0) can be detected. The PC microarray provides a general and easy-to-use method for the timely monitoring and eventual control of the global coronavirus pandemic.

Active Brownian particles in a biased periodic potential.

We study transport properties of an active Brownian particle with an Rayleigh-Helmholtz friction function in a biased periodic potential. In the absence of noise and depending on the parameters of the friction function and on the bias force, the motion of the particle can be in a locked state or in different running states. According to the type of solutions, the parameter plane of friction and bias force can be divided into four regions. In these different regimes, there is either only a locked state, only a running state, a bistability between locked and running states, or a bistability of two different running states (corresponding to a systematic motion to the left or right, respectively). In the presence of noise, the mean velocity depends in different ways on the noise intensity for the various parameter regimes. These dependences are explored by means of numerical simulations and simple analytical estimates for limiting cases.

Application of the metal ions as potential population biomarkers for wastewater-based epidemiology: estimating tobacco consumption in Southern China.

Wastewater-based epidemiology (WBE) is an objective approach for the estimation of population-level exposure to a wide range of substances, in which the use of a population biomarker (PB) could significantly reduce back-calculation errors. Although some endogenous or exogenous compounds such as cotinine and other hormones have been developed as PBs, more PBs still need to be identified and evaluated. This study aimed to propose a novel method to estimate population parameters from the mass load of metal ion biomarkers in wastewater, and estimate the consumption of tobacco in 24 cities in Southern China using the developed method. Daily wastewater samples were collected from 234 wastewater treatment plants (WWTPs) in 24 cities in Southern China. Atomic absorption spectroscopy (AAS) was applied to determine the concentrations of common health-related metal ions in wastewater, including sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), iron (Fe), and zinc (Zn), and compared them with the daily mass load of cotinine corresponding to catchment populations. The concentrations of cotinine in wastewater samples were measured using liquid chromatography-tandem mass spectrometry. There were clear and strong correlations between the target metal ion equivalent population and census data. The correlation coefficients (R) were RK = 0.78, RNa = 0.66, RCa = 0.81, RMg = 0.77, and RFe = 0.69, at p < 0.01 and R2 > 0.6. Subsequently, the combination of WBE and metal ion PBs was used to estimate tobacco consumption. Daily consumption of nicotine was estimated to be approximately 1.76 ± 1.19 mg/d/capita, equivalent to an average of 13.0 ± 8.75 cigarettes/d being consumed by smokers. The data on tobacco consumption in this study were consistent with those in traditional surveys in Southern China. The metal ion potassium is an appropriate PB for reflecting the real-time population and could be used to evaluate the tobacco consumption in WBE study.

Achilles tendon thickening does not affect elasticity and functional outcome after surgical repair of Achilles rupture: A retrospective study.

PURPOSE: Previous studies have confirmed that Achilles tendon occurs Achilles thickening after repair surgery of the rupture. Although this mechanism has been elucidated in the laboratory, there are few reports on its impact on clinical function. We designed a retrospective study to investigate the Achilles thickening after Achilles tendon rupture repair and its correlation between the elasticity and postoperative function. METHODS: In this retrospective analysis, patients who underwent surgical treatment for acute Achilles tendon rupture from April 2016 to April 2020 were included. All the patients were regularly followed up at 3 months, 1 year, and 2 years after surgery. American Orthopaedic Foot Ankle Surgeon (AOFAS) scale and Leppilahti score were used to evaluate functional outcomes. Achilles elasticity was measured by ultrasound shear wave of elasticity. Achilles thickening was calculated as maximal transverse and longitudinal diameter in cross-sectional plane of magnetic resonance scan. Sample t-tests was used for different follow-up periods. Correlation between Achilles thickening and other factors were analyzed using Pearson's method. p < 0.05 indicates a statistically significant difference. RESULTS: AOFAS scale and Leppilahti score at 1 year were significantly higher than at 3 months postoperatively (both p < 0.001). These functional scales were also improved at 2-year follow-up significantly (both p < 0.001). The dorsiflexion difference showed gradually recovery in each follow-up period (t = -17.907, p < 0.001). The elasticity of the Achilles appeared to continuously decreases during the postoperative follow-up period in all position sets (p < 0.001). In thickening evaluation, the cross-sectional area of the thickest plane of Achilles was significantly higher at 1 year postoperatively (310.5 ± 25.2) mm2 than that at 3 months postoperatively ((278.0 ± 26.2) mm2, t = -8.219, p < 0.001) and became thinner in 2-year magnetic resonance scan ((256.1 ± 15.1) mm2, t = 16.769, p < 0.001). The correlations between Achilles thickening, elasticity, and functional outcome did not show statistical significance (p > 0.05) in every follow-up period. CONCLUSION: Achilles tendon thickens after surgery in the 1st year, but begins to gradually return to thinning about 2 years after surgery. There was no significant correlation between the increase and decrease of thickening and the patients' clinical function scores, Achilles elasticity, and bilateral ankle dorsiflexion difference.

Template-Free Assembly of Functional RNAs by Loop-Closing Ligation.

The first ribozymes are thought to have emerged at a time when RNA replication proceeded via nonenzymatic template copying processes. However, functional RNAs have stable folded structures, and such structures are much more difficult to copy than short unstructured RNAs. How can these conflicting requirements be reconciled? Also, how can the inhibition of ribozyme function by complementary template strands be avoided or minimized? Here, we show that short RNA duplexes with single-stranded overhangs can be converted into RNA stem loops by nonenzymatic cross-strand ligation. We then show that loop-closing ligation reactions enable the assembly of full-length functional ribozymes without any external template. Thus, one can envisage a potential pathway whereby structurally complex functional RNAs could have formed at an early stage of evolution when protocell genomes might have consisted only of collections of short replicating oligonucleotides.

Associations of the Gut Microbiota Composition and Fecal Short-Chain Fatty Acids with Leukocyte Telomere Length in Children Aged 6 to 9 Years in Guangzhou, China: A Cross-sectional Study.

BACKGROUND: Telomere length (TL) serves as a marker of cellular senescence and appears to plateau between the age of 4 y and young adulthood, after which the gut microbiota are supposed to be established. However, scarce data are available regarding the correlation between gut microbiota composition and TL in the pediatric population. OBJECTIVES: We aimed to investigate whether the gut microbiota and the concentrations of SCFAs in feces are associated with leukocyte TL in children. METHODS: In total, 401 children aged 6-9 y from Guangzhou were enrolled in this cross-sectional study. qPCR was used to determine relative TL in peripheral blood leukocytes. The gut microbiota was characterized by 16S ribosomal RNA amplicon sequencing and the fecal concentrations of total SCFAs and SCFA subtypes were determined using HPLC. The multivariate methods with an unbiased variable selection (MUVR) algorithm and partial least square models were used to select predictable operational taxonomic units (OTUs). Further correlation analyses were performed based on multiple linear regression models with adjustment for covariates and false discovery rate. RESULTS: With the use of MUVR, 35 relevant and minimal optimal OTUs were finally selected. Multiple linear regression analysis showed that the abundance of several OTUs, including OTU334 (belonging to the genus Family XIII AD3011 group), OTU726 (belonging to the species Lachnoclostridium phocaeense), OTU1441 (belonging to the genus Ruminococcus torques group), OTU2553 (belonging to the genus Lachnospiraceae UCG-010), and OTU3375 (belonging to the family Lachnospiraceae), was negatively associated with leukocyte TL (ß: -0.187 to -0.142; false discovery rate (FDR)-corrected P value (PFDR) = 0.009-0.035]. However, neither SCFA subtype nor total SCFA content in feces exhibited significant associations with TL (ß: -0.032 to 0.048; PFDR = 0.915-0.969). CONCLUSIONS: The gut microbiota, but not fecal SCFA concentration, was significantly associated with TL in this pediatric population.

Advanced Lithium Primary Batteries: Key Materials, Research Progresses and Challenges.

In recent years, with the vigorous development and gradual deployment of new energy vehicles, more attention has been paid to the research on lithium-ion batteries (LIBs). Compared with the booming LIBs, lithium primary batteries (LPBs) own superiority in specific energy and self-discharge rate and are usually applied in special fields such as medical implantation, aerospace, and military. Widespread application in special fields also means more stringent requirements for LPBs in terms of energy density, working temperature range and shelf life. Therefore, how to obtain LPBs with high energy density, wide operational temperature range and long storage life is of great importance in future development. In view of the above, this paper reviews the latest research on LPBs in cathode, anode and electrolyte over the years, and puts forward relevant insights for LPBs, along with the intention to explore avenues for the design of LPBs components in the coming decades and promote further development in this field.

Clinical utility and cost-effectiveness analysis of chromosome testing concomitant with chromosomal microarray of patients with constitutional disorders in a U.S. academic medical center.

Chromosomal microarray (CMA) is now widely used as first-tier testing for the detection of copy number variants (CNVs) and absence of heterozygosity (AOH) in patients with multiple congenital anomalies (MCA), autism spectrum disorder (ASD), developmental delay (DD), and/or intellectual disability (ID). Chromosome analysis is commonly used to complement CMA in the detection of balanced genomic aberrations. However, the cost-effectiveness and the impact on clinical management of chromosome analysis concomitant with CMA were not well studied, and there is no consensus on how to best utilize these two tests. To assess the clinical utility and cost-effectiveness of chromosome analysis concomitant with CMA in patients with MCA, ASD, DD, and/or ID, we retrospectively analyzed 3,360 postnatal cases for which CMA and concomitant chromosome analysis were performed in the Colorado Genetic Laboratory (CGL) at the University Of Colorado School Of Medicine. Chromosome analysis alone yielded a genetic diagnosis in two patients (0.06%) and contributed additional information to CMA results in 199 (5.92%) cases. The impact of abnormal chromosome results on patient management was primarily related to counseling for reproductive and recurrence risks assessment (101 cases, 3.01%) while a few (5 cases, 0.15%) led to changes in laboratory testing and specialist referral (25 cases, 0.74%). The incremental cost-effectiveness ratio (ICER) of combined testing demonstrated the cost of each informative chromosome finding was significantly higher for patients with clinically insignificant (CI) CMA findings versus clinically significant (CS) CMA results. Our results suggest that a stepwise approach with CMA testing with reflex to chromosome analysis on cases with CS CMA findings is a more cost-effective testing algorithm for patients with MCA, ASD, and/or DD/ID.

A developed non-smooth coordinate transformation for general bilateral vibro-impact systems.

Discontinuity and non-smoothness of system displacement and velocity caused by mechanical impact make the related research on dynamics of vibro-impact systems very difficult and complex. For the sake of bypassing the problems resulting from impact to some extent, Zhuravlev and Ivanov coordinate transformations were proposed, which can effectively convert the vibro-impact system to one without impact terms. In this paper, a more direct and universal transformation for general bilateral rigid vibro-impact systems is proposed. It is inspired by the main technique of Ivanov transformation, which makes the trajectories remain continuous in an auxiliary phase space. It can be directly applied to common vibro-impact systems, whether the positions of barriers are symmetrical or the restitution coefficients of barriers on both sides are consistent. In particular, this method can also be applied to the unilateral vibro-impact system. Validity of the proposed methodology is examined by means of case studies.

The Origin of Translation: Bridging the Nucleotides and Peptides.

Extant biology uses RNA to record genetic information and proteins to execute biochemical functions. Nucleotides are translated into amino acids via transfer RNA in the central dogma. tRNA is essential in translation as it connects the codon and the cognate amino acid. To reveal how the translation emerged in the prebiotic context, we start with the structure and dissection of tRNA, followed by the theory and hypothesis of tRNA and amino acid recognition. Last, we review how amino acids assemble on the tRNA and further form peptides. Understanding the origin of life will also promote our knowledge of artificial living systems.