Orthogonal-array dynamic molecular sieving of propylene/propane mixtures.

Rigid molecular sieving materials work well for small molecules with the complete exclusion of large ones1-3, and molecules with matching physiochemical properties may be separated using dynamic molecular sieving materials4-6. Metal-organic frameworks (MOFs)7-9 are known for their precise control of structures and functions on a molecular level10-15. However, the rational design of local flexibility in the MOF framework for dynamic molecular sieving remains difficult and challenging. Here we report a MOF material (JNU-3a) featuring one-dimension channels with embedded molecular pockets opening to propylene (C3H6) and propane (C3H8) at substantially different pressures. The dynamic nature of the pockets is revealed by single-crystal-to-single-crystal transformation upon exposure of JNU-3a to an atmosphere of C3H6 or C3H8. Breakthrough experiments demonstrate that JNU-3a can realize high-purity C3H6 (≥99.5%) in a single adsorption-desorption cycle from an equimolar C3H6/C3H8 mixture over a broad range of flow rates, with a maximum C3H6 productivity of 53.5 litres per kilogram. The underlying separation mechanism-orthogonal-array dynamic molecular sieving-enables both large separation capacity and fast adsorption-desorption kinetics. This work presents a next-generation sieving material design that has potential for applications in adsorptive separation.

Janus Membranes Patch Achieves High-Quality Tendon Repair: Inhibiting Exogenous Healing and Promoting Endogenous Healing.

The imbalance between endogenous and exogenous healing is the fundamental reason for the poor tendon healing. In this study, a Janus patch was developed to promote endogenous healing and inhibit exogenous healing, leading to improved tendon repair. The upper layer of the patch is a poly(dl-lactide-co-glycolide)/polycaprolactone (PLGA/PCL) nanomembrane (PMCP-NM) modified with poly(2-methylacryloxyethyl phosphocholine) (PMPC), which created a lubricated and antifouling surface, preventing cell invasion and mechanical activation. The lower layer is a PLGA/PCL fiber membrane loaded with fibrin (Fb) (Fb-NM), serving as a temporary chemotactic scaffold to regulate the regenerative microenvironment. In vitro, the Janus patch effectively reduced 92.41% cell adhesion and 79.89% motion friction. In vivo, the patch inhibited tendon adhesion through the TGF-ß/Smad signaling pathway and promoted tendon maturation. This Janus patch is expected to provide a practical basis and theoretical guidance for high-quality soft tissue repair.

Surface Chemistry Regulation in Cu4I4-Triazolate Metal-Organic Frameworks for One-Step C3H6 Purification from Quaternary C3 Mixtures.

C3H6 is a crucial building block for many chemicals, yet separating it from other C3 hydrocarbons presents a significant challenge. Herein, we report a hydrolytically stable Cu4I4-triazolate metal-organic framework (MOF) (JNU-9-CH3) featuring 1D channels decorated with readily accessible iodine and nitrogen atoms from Cu4I4 clusters and triazolate linkers, respectively. The exposed iodine and nitrogen atoms allow for cooperative binding of C3 hydrocarbons, as evidenced by in situ single-crystal crystallography and Raman spectroscopy studies. As a result, JNU-9-CH3 exhibits substantially stronger binding affinity for C3H4, CH2═C═CH2, and C3H8 than that for C3H6. Breakthrough experiments confirm its ability to directly separate C3H6 (≥99.99%) from C3H4/CH2═C═CH2/C3H8/C3H6 mixtures at varying ratios and flow rates. Overall, we illustrate the cooperative binding of C3 hydrocarbons in a Cu4I4-triazolate MOF and its highly efficient C3H6 purification from quaternary C3 mixtures. The study highlights the potential of MOF adsorbents with metal-iodide clusters for cooperative bindings and hydrocarbon separations.

Analysis of water quality indexes and their relationships with vegetation using self-organizing map and geographically and temporally weighted regression.

Natural vegetation has been proved to promote water purification in previous studies, while the relevant laws has not been excavated systematically. This research explored the relationships between vegetation cover and water quality indexes in Liaohe River Basin in China combined with self-organizing map (SOM) and geographically and temporally weighted regression (GTWR) innovatively and systematically based on the distributing heterogeneity of water quality conditions. Results showed that the central and northeast regions of the study area had serious organic and nutrient pollution, which needed targeted treatment. And SOM verified that high vegetation coverage with retention potential of organic and inorganic pollutants as well as nutrients improved water quality to some degree, while the excessive discharges of pollutants still had serious threats to nearby water environment despite the purification function of vegetation. GTWR indicated that the waterside vegetation was beneficial for dissolved oxygen increasing and contributed to the decreasing of organic pollutants and inorganic pollutants with reducibility. Natural vegetation also obsorbed nutrients like TN and TP to some degree. However, the retential potential of nitrogen and organic pollutants became not obvious when there were heavy pollution, which demonstrated that pollution sources should be controlled despite the purification function of vegetation. This study implied that natural vegetation purified water quality to some degree, while this function could not be revealed when there was too heavy pollution. These findings underscore that the pollutant discharge should be controlled though the natural vegetation in ecosystem promoted the purification of water bodies.

EZH2 regulates pancreatic cancer cells through E2F1, GLI1, CDK3, and Mcm4.

Pancreatic cancer (PC) is one of the most common malignant tumors in digestive tract. To explore the role of epigenetic factor EZH2 in the malignant proliferation of PC, so as to provide effective medical help in PC. Sixty paraffin sections of PC were collected and the expression of EZH2 in PC tissues was detected by immunohistochemical assay. Three normal pancreas tissue samples were used as controls. The regulation of EZH2 gene on proliferation and migration of normal pancreatic cell and PC cell were determined by MTS, colony forming, Ki-67 antibody, scratch and Transwell assays. Through differential gene annotation and differential gene signaling pathway analysis, differentially expressed genes related to cell proliferation were selected and verified by RT-qPCR. EZH2 is mainly expressed in the nuclei of pancreatic tumor cells, but not in normal pancreatic cells. The results of cell function experiments showed that EZH2 overexpression could enhance the proliferation and migration ability of PC cell BXPC-3. Cell proliferation ability increased by 38% compared to the control group. EZH2 knockdown resulted in reduced proliferation and migration ability of cells. Compared with control, proliferation ability of cells reduced by 16%-40%. The results of bioinformatics analysis of transcriptome data and RT-qPCR demonstrated that EZH2 could regulate the expression of E2F1, GLI1, CDK3 and Mcm4 in normal and PC cells. The results revealed that EZH2 might regulate the proliferation of normal pancreatic cell and PC cell through E2F1, GLI1, CDK3 and Mcm4.

Strategies to build more effective interventions for elder abuse: a focus group study of nursing and social work professionals in Hong Kong.

BACKGROUND: One in six older adults living in communities experience abuse and neglect. Elder abuse has serious consequences for individuals, families, and society, including mortality, physical and psychological morbidities, and increased care requirements. Timely and effective interventions for elder abuse should therefore be a priority. This study used a qualitative focus group approach to address the following questions: What are the essential elements of elder abuse interventions? What can be done to improve current interventions? METHOD: The 32 participants in this focus group study included social workers, medical social workers, and nurses from seven organizations who shared their knowledge and insights. All sessions were conducted online, audio-recorded, and transcribed verbatim. Three researchers with backgrounds in social work and psychology independently coded the transcripts and agreed on the themes emerging from the focus groups. RESULTS: Based on the experiences of frontline helping professionals in Hong Kong, we highlighted the key factors for effective elder abuse intervention: 1) identification and assessment; 2) essential skills and attitudes; 3) elements of effective interventions; 4) collaborative efforts across disciplines and agencies; and 5) raising awareness among professionals and the public. CONCLUSIONS: Training can equip frontline professionals with the necessary skills to identify elder abuse cases and to assess the risk of abuse. Effective interventions should not only address clients' safety and need for tangible support but also respect their autonomy and privacy. A client-centered, strength-based approach that involves supportive peers and addresses the complex family relationships involved can be useful. Interventions should also involve cross-discipline and cross-agency collaboration.

Establishment of a typing model for diffuse large B-cell lymphoma based on B-cell receptor repertoire sequencing.

BACKGROUND: The purpose of this study was to construct a new typing model for diffuse large B-cell lymphoma (DLBCL) patients based on the B-cell receptor (BCR) and explore its potential molecular mechanism. METHODS: BCR repertoire sequencing and whole-exome sequencing were performed on formalin-fixed paraffin-embedded samples from 12 DLBCL patients. Subsequently, a typing model was built with cluster analysis, and prognostic indicators between the two groups were compared to verify the typing model. Then, mutation and bioinformatics analyses were conducted to investigate the potential biomarkers of prognostic differences between the two groups. RESULTS: Based on BCR sequencing data, we divided patients into two clusters (cluster 1 and cluster 2); this classification differed from the traditional typing method (GCB and non-GCB), in which cluster 1 included some non-GCB patients. The progression-free survival (PFS), overall survival (OS), metastasis and Shannon diversity index of IGH V-J and survival after chemotherapy were significantly different (P < 0.05) between the two clusters, but no statistical significance was found between the GCB and non-GCB groups. The mutation status of 248 genes was significantly different between cluster 1 and cluster 2. Among them, FTSJ3, MAGED2, and ODF3L2 were the specific mutated genes in all patients in cluster 2, and these genes could be considered critical to the different prognoses of the two clusters of DLBCL patients. CONCLUSION: We constructed a new typing model of DLBCL based on BCR repertoire sequencing that can better predict the survival time after chemotherapy. FTSJ3, MAGED2, and ODF3L2 may represent key genes for the difference in prognosis between the two clusters.

Cage-Interconnected Metal-Organic Framework with Tailored Apertures for Efficient C2H6/C2H4 Separation under Humid Conditions.

Metal-organic frameworks (MOFs) with open metal sites (OMSs) have been shown to preferentially adsorb unsaturated hydrocarbons such as C2H4 due to the formation of π-complexation. However, the adsorption capacity and selectivity might well be dampened under humid conditions because OMSs could be easily poisoned in the presence of water vapor. C2H6-selective adsorbents with less hydrophilic environments, on the other hand, not only could effectively minimize the impact of humidity on separation capacity but also could directly produce high-purity C2H4 from C2H6/C2H4 mixtures. Here, we report a C2H6-selective MOF (JNU-2) underlying a rare xae topology. Its cage-like cavities are interconnected through apertures with a limiting diameter of ca. 3.7 Å, which is in the domain of kinetic diameters of C2H4 and C2H6 molecules. Molecular modeling studies suggest the four oxygen atoms on aperture are poised to preferentially interact with C2H6 through multiple C-H···O hydrogen bonding, rendering JNU-2 an enhanced C2H6 selectivity. Indeed, experimental results reveal that JNU-2 not only takes up a great amount of C2H6 comparable to other top-performing C2H6-selective MOFs but also displays excellent separation capacity even under humid conditions; moreover, it can be easily regenerated at room temperature owing to its moderate adsorption enthalpy. This work successfully demonstrated a strategy of balancing adsorption capacity and selectivity for C2H6 by designing MOF materials with cavities interconnected through tailored apertures. The apertures function as screening sites for C2H6 selectivity, while the internal cavities provide space for large adsorption.

Induced Fit of C2 H2 in a Flexible MOF Through Cooperative Action of Open Metal Sites.

Porous materials that can undergo pore-structure adjustment to better accommodate specific molecules are ideal for separation and purification. Here, we report a stable microporous metal-organic framework, JNU-1, featuring one-dimensional diamond-shaped channels with a high density of open metal sites arranged on the surface for the cooperative binding of acetylene. Together with its framework flexibility and appropriate pore geometry, JNU-1 exhibits an induced-fit behavior for acetylene. The specific binding sites and continuous framework adaptation upon increased acetylene pressure are validated by molecular modeling and in situ X-ray diffraction study. This unique induced-fit behavior endows JNU-1 with an unprecedented increase in the acetylene binding affinity (adsorption enthalpy: up to 47.6 kJ mol-1 at ca. 2.0 mmol g-1 loading).

Similarity evaluation of DNA sequences based on frequent patterns and entropy.

BACKGROUND: DNA sequence analysis is an important research topic in bioinformatics. Evaluating the similarity between sequences, which is crucial for sequence analysis, has attracted much research effort in the last two decades, and a dozen of algorithms and tools have been developed. These methods are based on alignment, word frequency and geometric representation respectively, each of which has its advantage and disadvantage. RESULTS: In this paper, for effectively computing the similarity between DNA sequences, we introduce a novel method based on frequency patterns and entropy to construct representative vectors of DNA sequences. Experiments are conducted to evaluate the proposed method, which is compared with two recently-developed alignment-free methods and the BLASTN tool. When testing on the ß-globin genes of 11 species and using the results from MEGA as the baseline, our method achieves higher correlation coefficients than the two alignment-free methods and the BLASTN tool. CONCLUSIONS: Our method is not only able to capture fine-granularity information (location and ordering) of DNA sequences via sequence blocking, but also insensitive to noise and sequence rearrangement due to considering only the maximal frequent patterns. It outperforms major existing methods or tools.

Should diabetic ketosis without acidosis be included in ketosis-prone type 2 diabetes mellitus?

BACKGROUND: The incidence of ketosis-prone type 2 diabetes is very low except for people of sub-Saharan African origin and African Americans. However, there also are some type 2 diabetes patients with diabetic ketosis without acidosis (DKWA). We question whether DKWA should be included as a subtype of ketosis-prone type 2 diabetes mellitus and compared the clinical characteristics of DKWA and diabetic ketoacidosis (DKA) patients. METHODS: The study population consisted of 594 consecutive unrelated Chinese inpatients with newly diagnosed type 2 diabetes. Demographic and clinical characteristics (age, gender, family history of diabetes, body mass index, blood pressure and plasma lipid parameters) were recorded. The patients were divided into ketosis-resistant diabetes (KRD), DKWA and DKA groups on the basis of urinary ketones, blood pH and bicarbonate levels. The blood glucose and c-peptide levels of the patients were also evaluated. RESULTS: The prevalence of KRD, DKWA and DKA were 78.33%, 19.72% and 1.95%, respectively, in the study population. The clinical characteristics of patients with DKWA group patients were similar to those with DKA, except that DKA patients had higher blood glucose and deteriorated ß cell function. CONCLUSIONS: Diabetic ketosis without acidosis and DKA patients share similar clinical characteristics; DKWA should be considered ketosis-prone type 2 diabetes. Therefore, the prevalence of ketosis-prone type 2 diabetes might be underestimated.

Blind spots of universal primers and specific FISH probes for functional microbe and community characterization in EBPR systems.

Fluorescence in situ hybridization (FISH) and 16S rRNA gene amplicon sequencing are commonly used for microbial ecological analyses in biological enhanced phosphorus removal (EBPR) systems, the successful application of which was governed by the oligonucleotides used. We performed a systemic evaluation of commonly used probes/primers for known polyphosphate-accumulating organisms (PAOs) and glycogen-accumulating organisms (GAOs). Most FISH probes showed blind spots and covered nontarget bacterial groups. Ca. Competibacter probes showed promising coverage and specificity. Those for Ca. Accumulibacter are desirable in coverage but targeted out-group bacteria, including Ca. Competibacter, Thauera, Dechlorosoma, and some polyphosphate-accumulating Cyanobacteria. Defluviicoccus probes are good in specificity but poor in coverage. Probes targeting Tetrasphaera or Dechloromonas showed low coverage and specificity. Specifically, DEMEF455, Bet135, and Dech453 for Dechloromonas covered Ca. Accumulibacter. Special attentions are needed when using these probes to resolve the PAO/GAO phenotype of Dechloromonas. Most species-specific probes for Ca. Accumulibacter, Ca. Lutibacillus, Ca. Phosphoribacter, and Tetrasphaera are highly specific. Overall, 1.4% Ca. Accumulibacter, 9.6% Ca. Competibacter, 43.3% Defluviicoccus, and 54.0% Dechloromonas in the MiDAS database were not covered by existing FISH probes. Different 16S rRNA amplicon primer sets showed distinct coverage of known PAOs and GAOs. None of them covered all members. Overall, 520F-802R and 515F-926R showed the most balanced coverage. All primers showed extremely low coverage of Microlunatus (<36.0%), implying their probably overlooked roles in EBPR systems. A clear understanding of the strength and weaknesses of each probe and primer set is a premise for rational evaluation and interpretation of obtained community results.

Integrated genomics provides insights into the evolution of the polyphosphate accumulation trait of Ca. Accumulibacter.

Candidatus Accumulibacter, a prominent polyphosphate-accumulating organism (PAO) in wastewater treatment, plays a crucial role in enhanced biological phosphorus removal (EBPR). The genetic underpinnings of its polyphosphate accumulation capabilities, however, remain largely unknown. Here, we conducted a comprehensive genomic analysis of Ca. Accumulibacter-PAOs and their relatives within the Rhodocyclaceae family, identifying 124 core genes acquired via horizontal gene transfer (HGT) at its least common ancestor. Metatranscriptomic analysis of an enrichment culture of Ca. Accumulibacter revealed active transcription of 44 of these genes during an EBPR cycle, notably including the polyphosphate kinase 2 (PPK2) gene instead of the commonly recognized polyphosphate kinase 1 (PPK1) gene. Intriguingly, the phosphate regulon (Pho) genes showed minimal transcriptions, pointing to a distinctive fact of Pho dysregulation, where PhoU, the phosphate signaling complex protein, was not regulating the high-affinity phosphate transport (Pst) system, resulting in continuous phosphate uptake. To prevent phosphate toxicity, Ca. Accumulibacter utilized the laterally acquired PPK2 to condense phosphate into polyphosphate, resulting in the polyphosphate-accumulating feature. This study provides novel insights into the evolutionary emergence of the polyphosphate-accumulating trait in Ca. Accumulibacter, offering potential advancements in understanding the PAO phenotype in the EBPR process.

Two new clades recovered at high temperatures provide novel phylogenetic and genomic insights into Candidatus Accumulibacter.

Candidatus Accumulibacter, a key genus of polyphosphate-accumulating organisms, plays key roles in lab- and full-scale enhanced biological phosphorus removal (EBPR) systems. A total of 10 high-quality Ca. Accumulibacter genomes were recovered from EBPR systems operated at high temperatures, providing significantly updated phylogenetic and genomic insights into the Ca. Accumulibacter lineage. Among these genomes, clade IIF members SCELSE-3, SCELSE-4, and SCELSE-6 represent the to-date known genomes encoding a complete denitrification pathway, suggesting that Ca. Accumulibacter alone could achieve complete denitrification. Clade IIC members SSA1, SCUT-1, SCELCE-2, and SCELSE-8 lack the entire set of denitrifying genes, representing to-date known non-denitrifying Ca. Accumulibacter. A pan-genomic analysis with other Ca. Accumulibacter members suggested that all Ca. Accumulibacter likely has the potential to use dicarboxylic amino acids. Ca. Accumulibacter aalborgensis AALB and Ca. Accumulibacter affinis BAT3C720 seemed to be the only two members capable of using glucose for EBPR. A heat shock protein Hsp20 encoding gene was found exclusively in genomes recovered at high temperatures, which was absent in clades IA, IC, IG, IIA, IIB, IID, IIG, and II-I members. High transcription of this gene in clade IIC members SCUT-2 and SCUT-3 suggested its role in surviving high temperatures for Ca. Accumulibacter. Ambiguous clade identity was observed for newly recovered genomes (SCELSE-9 and SCELSE-10). Five machine learning models were developed using orthogroups as input features. Prediction results suggested that they belong to a new clade (IIK). The phylogeny of Ca. Accumulibacter was re-evaluated based on the laterally derived polyphosphokinase 2 gene, showing improved resolution in differentiating different clades.

Candidatus Thiothrix phosphatis SCUT-1: A novel polyphosphate-accumulating organism abundant in the enhanced biological phosphorus removal system.

A novel coccus Thiothrix-related polyphosphate-accumulating organism (PAO) was enriched in an acetate-fed enhanced biological phosphorus removal (EBPR) system. High EBPR performance was achieved for an extended period (>100 days). A high-quality draft genome (completeness 97.2 %, contamination 3.26 %) was retrieved, representing a novel Thiothrix species (with similarity<93.2 % to known Thiothrix species), and was denoted as 'Candidatus Thiothrix phosphatis SCUT-1'. Its acetate uptake rate (6.20 mmol C/g VSS/h) surpassed most Ca. Accumulibacter and known glycogen-accumulating organisms (GAOs), conferring their predominance in the acetate-fed system. Metatranscriptomic analysis suggested that Ca. Thiothrix phosphatis SCUT-1 employed both low- and high-affinity pathways for acetate activation, and both the conventional (PhaABC) pathway and the fatty acid ß-oxidation pathway for PHA synthesis; additionally, a much more efficient FAD-dependent malate: quinone oxidoreductase (MQO) were encoded and employed than the traditional malate dehydrogenase (MDH) to oxidize malate to oxaloacetate in the TCA and glyoxylate cycle, collectively contributing to a higher acetate utilization and processing rate of this microorganism. Batch tests further demonstrated the versatile ability of this PAO in using VFA (acetate, propionate, and butyrate), lactate, amino acids (aspartate and glutamate), and glucose as carbon sources for EBPR, showing a partially overlapped but unique ecological niche of this microorganism comparing to Ca. Accumulibacter and known GAOs. A metabolic model was built for Ca. Thiothrix phosphatis SCUT-1 using the above-mentioned carbon sources for EBPR. Overall, this study represents the first comprehensive characterization of the physiology and metabolic characteristics of representative coccus Thiothrix-related PAOs, which are expected to provide new insights into PAO microbiology in EBPR systems.

Relating the carbon sources to denitrifying community in full-scale wastewater treatment plants.

Carbon source is a key factor determining the denitrifying effectiveness and efficiency in wastewater treatment plants (WWTPs). Whereas, the relationships between diverse and distinct denitrifying communities and their favorable carbon sources in full-scale WWTPs were not well-understood. This study performed a systematic analysis of the relationships between the denitrifying community and carbon sources by using 15 organic compounds from four categories and activated sludge from 8 full-scale WWTPs. Results showed that, diverse denitrifying bacteria were detected with distinct relative abundances in 8 WWTPs, such as Haliangium (1.98-4.08%), Dechloromonas (2.00-3.01%), Thauera (0.16-1.06%), Zoogloea (0.09-0.43%), and Rhodoferax (0.002-0.104%). Overall, acetate resulted in the highest denitrifying activities (1.21-4.62 mg/L/h/gMLSS), followed by other organic acids (propionate, butyrate and lactate, etc.). Detectable dissimilatory nitrate reduction to ammonium (DNRA) was observed for all 15 carbon sources. Methanol and glycerol resulted in the highest DRNA. Acetate, butyrate, and lactate resulted in the lowest DNRA. Redundancy analysis and 16S cDNA amplicon sequencing suggested that carbon sources within the same category tended to correlate to similar denitrifiers. Methanol and ethanol were primarily correlated to Haliangium. Glycerol and amino acids (glutamate and aspartate) were correlated to Inhella and Sphaerotilus. Acetate, propionate, and butyrate were positively correlated to a wide range of denitrifiers, explaining the high efficiency of these carbon sources. Additionally, even within the same genus, different amplicon sequence variants (ASVs) performed distinctly in terms of carbon source preference and denitrifying capabilities. These findings are expected to benefit carbon source formulation and selection in WWTPs.

Surface engineering on a microporous metal-organic framework to boost ethane/ethylene separation under humid conditions.

Recently, examples of metal-organic frameworks (MOFs) have been identified displaying ethane (C2H6) over ethylene (C2H4) adsorption selectivity. However, it remains a challenge to construct MOFs with both large C2H6 adsorption capacity and high C2H6/C2H4 adsorption selectivity, especially under humid conditions. Herein, we reported two isoreticular MOF-5 analogues (JNU-6 and JNU-6-CH3) and their potential applications in one-step separation of C2H4 from C2H6/C2H4 mixtures. The introduction of CH3 groups not only reduces the pore size from 5.4 Å in JNU-6 to 4.1 Å in JNU-6-CH3 but also renders an increased electron density on the pyrazolate N atoms of the organic linker. JNU-6-CH3 retains its framework integrity even after being immersed in water for six months. More importantly, it exhibits large C2H6 adsorption capacity (4.63 mmol g-1) and high C2H6/C2H4 adsorption selectivity (1.67) due to the optimized pore size and surface function. Breakthrough experiments on JNU-6-CH3 demonstrate that C2H4 can be directly separated from C2H6/C2H4 (50/50, v/v) mixtures, affording benchmark productivity of 22.06 and 18.71 L kg-1 of high-purity C2H4 (≥99.95%) under dry and humid conditions, respectively.

Micro-nano hierarchical scaffold providing temporal-matched biological constraints for tendon reconstruction.

Due to the limitations of tendon biology, high-quality tendon repair remains a clinical and scientific challenge. Here, a micro-nano hierarchical scaffold is developed to promote orderly tendon regeneration by providing temporal-matched biological constraints. In short, fibrin (Fb), which provides biological constraints, is loaded into poly (DL-lactide-co-glycolide) nanoyarns with suitable degradation cycles (Fb-loaded nanofiber yarns (Fb-NY)). Then further combined with braiding technology, temporary chemotactic Fb scaffolds with tendon extracellular matrix-like structures are obtained to initiate the regeneration process. At the early stage of healing (2 w), the regeneration microenvironment is regulated (inducing M2 macrophages and restoring the early blood supply necessary for healing) by Fb, and the alignment of cells and collagen is induced by nanoyarn. At the late healing stage (8 w), with the degradation of Fb-NY, non-functional vascular regression occurs, and the newborn tissues gradually undergo load-bearing remodeling, restoring the anvascularous and ordered structure of the tendon. In summary, the proposed repair strategy provides temporal-matched biological constraints, offering a potential pathway to reconstruct the ordered structure and function of tendons.

Candidatus Accumulibacter use fermentation products for enhanced biological phosphorus removal.

Previous research suggested that two major groups of polyphosphate-accumulating organisms (PAOs), i.e., Ca. Accumulibacter and Tetrasphaera, play cooperative roles in enhanced biological phosphorus removal (EBPR). The fermentation of complex organic compounds by Tetrasphaera provides carbon sources for Ca. Accumulibacter. However, the viability of the fermentation products (e.g., lactate, succinate, alanine) as carbon sources for Ca. Accumulibacter and their potential effects on the metabolism of Ca. Accumulibacter were largely unknown. This work for the first time investigated the capability and metabolic details of Ca. Accumulibacter cognatus clade IIC strain SCUT-2 (enriched in a lab-scale reactor with a relative abundance of 42.8%) in using these fermentation products for EBPR. The enrichment culture was able to assimilate lactate and succinate with the anaerobic P release to carbon uptake ratios of 0.28 and 0.36 P mol/C mol, respectively. In the co-presence of acetate, the uptake of lactate was strongly inhibited, since two substrates shared the same transporter as suggested by the carbon uptake bioenergetic analysis. When acetate and succinate were fed at the same time, Ca. Accumulibacter assimilated two carbon sources simultaneously. Proton motive force (PMF) was the key driving force (up to 90%) for the uptake of lactate and succinate by Ca. Accumulibacter. Apart from the efflux of proton in symport with phosphate via the inorganic phosphate transport system, translocation of proton via the activity of fumarate reductase contributed to the generation of PMF, which agreed with the fact that PHV was a major component of PHA when lactate and succinate were used as carbon sources, involving the succinate-propionate pathway. Metabolic models for the usage of lactate and succinate by Ca. Accumulibacter for EBPR were built based on the combined physiological, biochemical, metagenomic, and metatranscriptomic analyses. Alanine was shown as an invalid carbon source for Ca. Accumulibacter. Instead, it significantly and adversely affected Ca. Accumulibacter-mediated EBPR. Phosphate release was observed without alanine uptake. Significant inhibitions on the aerobic phosphate uptake was also evident. Overall, this study suggested that there might not be a simply synergic relationship between Ca. Accumulibacter and Tetrasphaera. Their interactions would largely be determined by the kind of fermentation products released by the latter.

Association of IRS-1 and IRS-2 genes polymorphisms with polycystic ovary syndrome: a meta-analysis.

Insulin resistance (IR) plays an important role in the pathogenesis of polycystic ovary syndrome (PCOS) which is a common disorder in premenopausal women. The association between the single nucleotide polymorphisms (SNPs) of insulin receptor substrate (IRS) gene and PCOS in several populations has been studied, but the results are conflicting. The aim of this study was undertaken to investigate association of IRS-1 and IRS-2 genes polymorphisms with PCOS by conducting a meta-analysis. Literature search was conducted through PubMed and EMBASE databases (up to July 31, 2011). Fifteen articles with 1,358 cases and 1,561 controls were enrolled in the meta-analysis of the association between Gly972Arg variant and PCOS, and five articles with 519 cases and 883 controls were enrolled in the meta-analysis of Gly1057Asp variant. Summary odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using fixed and random-effects models. The Q-statistic test was used to assess heterogeneity, and Begg's test and Egger's test were used to evaluate publication bias. Sensitivity analysis was also performed. Our results indicated that A allele of Gly972Arg conferred a significantly increased risk of PCOS compared with G allele (OR = 1.91, 95% CI: 1.36-2.68). However, in Gly1057Asp polymorphism the OR of allele A vs. G is 0.92 (95% CI: 0.72, 1.18). Our meta-analysis suggested that IRS-1 Gly972Arg polymorphism might be considered a significant risk for PCOS. Otherwise, no significant associations were observed in IRS-2 Gly1057Asp polymorphism which needs to be further confirmed by further studies.