Achieving Remarkable Specific Mechanical Strength and Energy Absorption Capacity in SiC Nanowire Networks through Graded Structural Design.

Lightweight porous ceramics with a unique combination of superior mechanical strength and damage tolerance are in significant demand in many fields such as energy absorption, aerospace vehicles, and chemical engineering; however, it is difficult to meet these mechanical requirements with conventional porous ceramics. Here, we report a graded structure design strategy to fabricate porous ceramic nanowire networks that simultaneously possess excellent mechanical strength and energy absorption capacity. Our optimized graded nanowire networks show a compressive strength of up to 35.6 MPa at a low density of 540 mg·cm-3, giving rise to a high specific compressive strength of 65.7 kN·m·kg-1 and a high energy absorption capacity of 17.1 kJ·kg-1, owing to a homogeneous distribution of stress upon loading. These values are top performance compared to other porous ceramics, giving our materials significant potential in various engineering fields.

Unraveling Lattice-Distortion Hardening Mechanisms in High-Entropy Carbides.

Uncovering the hardening mechanisms is of great importance to accelerate the design of superhard high-entropy carbides (HECs). Herein, the hardening mechanisms of HECs by a combination of experiments and first-principles calculations are systematically explored. The equiatomic single-phase 4- to 8-cation HECs (4-8HECs) are successfully fabricated by the two-step approach involving ultrafast high-temperature synthesis and hot-press sintering techniques. The as-fabricated 4-8HEC samples possess fully dense microstructures (relative densities of up to ≈99%), similar grain sizes, clean grain boundaries, and uniform compositions. With the elimination of these morphological properties, the monotonic enhancement of Vickers hardness and nanohardness of the as-fabricated 4-8HEC samples is found to be driven by the aggravation of lattice distortion. Further studies show no evident association between the enhanced hardness of the as-fabricated 4-8HEC samples and other potential indicators, including bond strength, valence electron concentration, electronegativity mismatch, and metallic states. The work unveils the underlying hardening mechanisms of HECs and offers an effective strategy for designing superhard HECs.

METTL3-m6A methylation inhibits the proliferation and viability of type II alveolar epithelial cells in acute lung injury by enhancing the stability and translation efficiency of Pten mRNA.

BACKGROUND: The pathogenesis of acute lung injury (ALI) involves a severe inflammatory response, leading to significant morbidity and mortality. N6-methylation of adenosine (m6A), an abundant mRNA nucleotide modification, plays a crucial role in regulating mRNA metabolism and function. However, the precise impact of m6A modifications on the progression of ALI remains elusive. METHODS: ALI models were induced by either intraperitoneal injection of lipopolysaccharide (LPS) into C57BL/6 mice or the LPS-treated alveolar type II epithelial cells (AECII) in vitro. The viability and proliferation of AECII were assessed using CCK-8 and EdU assays. The whole-body plethysmography was used to record the general respiratory functions. M6A RNA methylation level of AECII after LPS insults was detected, and then the "writer" of m6A modifications was screened. Afterwards, we successfully identified the targets that underwent m6A methylation mediated by METTL3, a methyltransferase-like enzyme. Last, we evaluated the regulatory role of METTL3-medited m6A methylation at phosphatase and tensin homolog (Pten) in ALI, by assessing the proliferation, viability and inflammation of AECII. RESULTS: LPS induced marked damages in respiratory functions and cellular injuries of AECII. The m6A modification level in mRNA and the expression of METTL3, an m6A methyltransferase, exhibited a notable rise in both lung tissues of ALI mice and cultured AECII cells subjected to LPS treatment. METTL3 knockdown or inhibition improved the viability and proliferation of LPS-treated AECII, and also reduced the m6A modification level. In addition, the stability and translation of Pten mRNA were enhanced by METTL3-mediated m6A modification, and over-expression of PTEN reversed the protective effect of METTL3 knockdown in the LPS-treated AECII. CONCLUSIONS: The progression of ALI can be attributed to the elevated levels of METTL3 in AECII, as it promotes the stability and translation of Pten mRNA through m6A modification. This suggests that targeting METTL3 could offer a novel approach for treating ALI.

Why do dipole moments of HCl-water clusters fail to determine acid dissociation?

This paper quantitatively examines why dipole moments of HCl(H2O)n=1-8 cannot serve as the dissociation criterion for acid molecules using the Hirshfeld-I approach. Also, we propose the possible experimental parameter 〈P(HCl)〉, whose statistical average enables the assessment of acid dissociation in mixed clusters. Furthermore, our calculations reveal that a minimum of four water molecules are necessary to dissociate an HCl molecule.

Dissociation of HBr in Water Clusters Based on a Hybrid Density Functional Approach.

The dissociation of acidic molecules within a microscopic water environment is crucial for understanding intermolecular interactions such as hydrogen bonding. This study explores the optimal configurations of HBr(H2O)n=1-7 using hybrid density functional theory. According to the different mixed cluster structures, the corresponding HBr bond lengths, single-point energies, and introduced proton-transfer parameters are computed and analyzed. The findings indicate that a minimum of three water molecules is necessary for the dissociation of HBr. Subsequently, this conclusion is reinforced through the decomposition of energy components between the acid molecule and water clusters, calculation of hydrogen bonding energies, and analysis of vibrational infrared spectroscopy.

Conservatively transmitted alleles of key agronomic genes provide insights into the genetic basis of founder parents in bread wheat (Triticum aestivum L.).

BACKGROUND: Founder parents play extremely important roles in wheat breeding. Studies into the genetic basis of founder parents and the transmission rules of favorable alleles are of great significance in improving agronomically important traits in wheat. RESULTS: Here, a total of 366 founder parents, widely grown cultivars, and derivatives of four representative founder parents were genotyped based on efficient kompetitive allele-specific PCR (KASP) markers in 87 agronomically important genes controlling yield, quality, adaptability, and stress resistance. Genetic composition analysis of founder parents and widely grown cultivars showed a consistently high frequency of favorable alleles for yield-related genes. This analysis further showed that other alleles favorable for resistance, strong gluten, dwarf size, and early heading date were also subject to selective pressure over time. By comparing the transmission of alleles from four representative founder parents to their derivatives during different breeding periods, it was found that the genetic composition of the representative founder parents was optimized as breeding progressed over time, with the number and types of favorable alleles carried gradually increasing and becoming enriched. There are still a large number of favorable alleles in wheat founder parents that have not been fully utilized in breeding selection. Eighty-seven agronomically important genes were used to construct an enrichment map that shows favorable alleles of four founder parents, providing an important theoretical foundation for future identification of candidate wheat founder parents. CONCLUSIONS: These results reveal the genetic basis of founder parents and allele transmission for 87 agronomically important genes and shed light on breeding strategies for the next generation of elite founder parents in wheat.

TaTPP-7A positively feedback regulates grain filling and wheat grain yield through T6P-SnRK1 signalling pathway and sugar-ABA interaction.

Grain size and filling are two key determinants of grain thousand-kernel weight (TKW) and crop yield, therefore they have undergone strong selection since cereal was domesticated. Genetic dissection of the two traits will improve yield potential in crops. A quantitative trait locus significantly associated with wheat grain TKW was detected on chromosome 7AS flanked by a simple sequence repeat marker of Wmc17 in Chinese wheat 262 mini-core collection by genome-wide association study. Combined with the bulked segregant RNA-sequencing (BSR-seq) analysis of an F2 genetic segregation population with extremely different TKW traits, a candidate trehalose-6-phosphate phosphatase gene located at 135.0 Mb (CS V1.0), designated as TaTPP-7A, was identified. This gene was specifically expressed in developing grains and strongly influenced grain filling and size. Overexpression (OE) of TaTPP-7A in wheat enhanced grain TKW and wheat yield greatly. Detailed analysis revealed that OE of TaTPP-7A significantly increased the expression levels of starch synthesis- and senescence-related genes involved in abscisic acid (ABA) and ethylene pathways. Moreover, most of the sucrose metabolism and starch regulation-related genes were potentially regulated by SnRK1. In addition, TaTPP-7A is a crucial domestication- and breeding-targeted gene and it feedback regulates sucrose lysis, flux, and utilization in the grain endosperm mainly through the T6P-SnRK1 pathway and sugar-ABA interaction. Thus, we confirmed the T6P signalling pathway as the central regulatory system for sucrose allocation and source-sink interactions in wheat grains and propose that the trehalose pathway components have great potential to increase yields in cereal crops.

Radiation pneumonia predictive model for radiotherapy in esophageal carcinoma patients.

BACKGROUND: The machine learning models with dose factors and the deep learning models with dose distribution matrix have been used to building lung toxics models for radiotherapy and achieve promising results. However, few studies have integrated clinical features into deep learning models. This study aimed to explore the role of three-dimension dose distribution and clinical features in predicting radiation pneumonitis (RP) in esophageal cancer patients after radiotherapy and designed a new hybrid deep learning network to predict the incidence of RP. METHODS: A total of 105 esophageal cancer patients previously treated with radiotherapy were enrolled in this study. The three-dimension (3D) dose distributions within the lung were extracted from the treatment planning system, converted into 3D matrixes and used as inputs to predict RP with ResNet. In total, 15 clinical factors were normalized and converted into one-dimension (1D) matrixes. A new prediction model (HybridNet) was then built based on a hybrid deep learning network, which combined 3D ResNet18 and 1D convolution layers. Machine learning-based prediction models, which use the traditional dosiomic factors with and without the clinical factors as inputs, were also constructed and their predictive performance compared with that of HybridNet using tenfold cross validation. Accuracy and area under the receiver operator characteristic curve (AUC) were used to evaluate the model effect. DeLong test was used to compare the prediction results of the models. RESULTS: The deep learning-based model achieved superior prediction results compared with machine learning-based models. ResNet performed best in the group that only considered dose factors (accuracy, 0.78 ± 0.05; AUC, 0.82 ± 0.25), whereas HybridNet performed best in the group that considered both dose factors and clinical factors (accuracy, 0.85 ± 0.13; AUC, 0.91 ± 0.09). HybridNet had higher accuracy than that of Resnet (p = 0.009). CONCLUSION: Based on prediction results, the proposed HybridNet model could predict RP in esophageal cancer patients after radiotherapy with significantly higher accuracy, suggesting its potential as a useful tool for clinical decision-making. This study demonstrated that the information in dose distribution is worth further exploration, and combining multiple types of features contributes to predict radiotherapy response.

Accurate and Wide-Voltage-Range Modeling of Electrowetting with a Lattice Boltzmann Approach.

The lattice Boltzmann method (LBM) has been widely used in multi-phase fluid mechanics and is known to be more computationally efficient than the traditional method of numerically solving Navier-Stokes and Cahn-Hilliard equations. Electrowetting is an important component of interfacial sciences, in which the liquid-liquid and solid-liquid interfaces are tuned by electrostatics. Modeling electrowetting using the LBM can be categorized into surface and bulk methods. By modifying the surface tension scalar, the surface method easily reproduces the fundamental Young-Lippmann (YL) equation at low voltages but fails to capture contact angle saturation at high voltages. With fully coupled hydrodynamics and electrostatics in the form of spatially dependent matrices, the bulk method can successfully show contact angle saturation, but it is often unable to reproduce the YL equation due to its intrinsic inaccuracies. The inaccuracies are mainly due to the fact that while the hydrodynamics are all described by continuous physical quantities in the framework of diffusive interfaces, the interfacial electrostatics are governed by discontinuous electric fields caused by sheet charge density. In this paper, we show that accurately modeling electrowetting using the LBM is non-trivial. Additional modeling work, especially the treatment of interfacial electric fields, is needed to recover the fundamental YL equation at low voltages and predict contact angle saturation at high voltages, with a systematic model validation over key parameters and applications.

Analysis of the risk factors of radiation pneumonitis and the predictive ability of dosiomics in non-small-cell lung cancer.

Purpose: This prospective study investigated the incidence of radiation pneumonitis (RP) after immunotherapy followed by radiotherapy in non-small-cell lung cancer, analyzed the risk factors for RP, and explored the predictive performance of dosimetry and dosiomics. Methods & materials: Risk factors for grade ≥2 RP were calculated by using a logistic regression model. Predictive performance was compared on the basis of area under the curve values. Results: Grade ≥2 RP occurred in 16 cases (26.7%). The AUC values of V5 Gy, gray-level dependence matrix-small dependence high gray-level emphasis (GLDM-SDHGLE) and combined features were 0.685, 0.724 and 0.734, respectively. Conclusion: Smoking history, bilateral lung V5 Gy and GLDM-SDHGLE were independent risk factors for RP. Dosiomics can effectively predict RP.

Genetic dissection of lutein content in common wheat via association and linkage mapping.

KEY MESSAGE: Genetic architecture controlling grain lutein content of common wheat was investigated through an integration of genome-wide association study (GWAS) and linkage analysis. Putative candidate genes involved in carotenoid metabolism and regulation were identified, which provide a basis for gene cloning and development of nutrient-enriched wheat varieties through molecular breeding. Lutein, known as 'the eye vitamin', is an important component of wheat nutritional and end-use quality. However, the genetic manipulation of grain lutein content (LUC) in common wheat has not previously been well studied. Here, quantitative trait loci (QTL) associated with the LUC measured by high performance liquid chromatography (HPLC) were first identified by integrating a genome-wide association study (GWAS) and linkage mapping. A Chinese wheat mini-core collection (MCC) of 262 accessions and a doubled haploid (DH) population derived from Jinchun 7 and L1219 were genotyped using the 90K SNP array. A total of 124 significant marker-trait associations (MTAs) on all 21 wheat chromosomes except for 1A, 4D, and 5B that formed 58 QTL were detected. Among them, six stable QTL were identified on chromosomes 2AL, 2DS, 3BL, 3DL, 7AL, and 7BS. Meanwhile, three of the ten QTL identified in the DH population, QLuc.5A.1 and QLuc.5A.2 on chromosome 5AL and QLuc.6A.2 on 6AS, were stable and independently explained 5.58-10.86% of the phenotypic variation. The QLuc.6A.2 region colocalized with two MTAs identified by GWAS. Moreover, 71 carotenoid metabolism-related candidate genes were identified, and the allelic effects were analyzed in the MCC panel based on the 90K array. Results revealed that the genes CYP97A3 (Chr. 6B) and CCD1 (Chr. 5A) were significantly associated with LUC. Additionally, the gene PSY3 (QLuc.5A.1) and several candidate genes involved in the methylerythritol 4-phosphate (MEP) pathways colocalized with stable QTL regions. The present study provides potential targets for future functional gene exploration and molecular breeding in common wheat.

Gradient Design of Vacancies and Their Positive Correlation with Electrochemical Anticorrosion Protection.

The contribution of defects to electrochemistry is a controversial but practically applicable subject. Meanwhile, it is challenging to obtain precisely a certain nonchemometric single phase in mixed-valence compounds. The precise design of nonchemometric single-phase WO3-x (x = 0, 0.1, 0.28, and 1) mixed-valence metal oxides (MVMOs) was achieved by the gradient intrinsic reduction method, and the correlation between oxygen vacancies and electrochemical anticorrosion protection was explored systematically. Then, the decisive role of periodic oxygen vacancies in electrochemical anticorrosion was confirmed. And the origin was the synergistic reaction of oxygen vacancy-upgraded photocathodic protection, vacancy-induced passivation, and mixed-valence reductive protection, which were brought about by the high oxygen vacancy concentration. Integrating the above three aspects, the WO2.72 MVMO showed the best electrochemical anticorrosion performance by increasing the resistance value to 7.67 times that of the epoxy resin coating. The establishment of a positive correlation between oxygen vacancy and corrosion protection in WO3-x (x = 0, 0.1, 0.28, and 1) materials can not only guide the design of MVMOs but also make an important contribution to the rapid precorrosion performance of the materials.

Cytotoxic Sesquiterpenoids from Atractylodes chinensis (DC.) Koidz.

Four new sesquiterpenoids named atrchiterpenes A-D (1-4), a new natural product (5), and twelve known compounds (6-17) were isolated from Atractylodes chinensis (DC.) Koidz. Compound 1 was a rare N-containing eudesmane-type sesquiterpenoid. Structure elucidation was performed by spectroscopic techniques, including 1D, 2D NMR spectra, and HR-ESI-MS. Compounds 6-11, 14, and 17 were reported from Atractylodes for the first time. All the isolated compounds were evaluated for cytotoxicity activity. Compound 16 showed moderate cytotoxicity against HepG2 cells with an IC50 value of 5.81±0.47.

Functional domains of the FgfrL1 receptor.

FgfrL1 is a novel growth factor receptor that is primarily expressed in musculoskeletal tissues and the kidney. FgfrL1-deficient mice have a malformed diaphragm and no kidneys. Such animals die immediately after birth because they are not able to inflate their lungs. The FgfrL1 molecule is composed of three extracellular Ig domains, a transmembrane helix and a short intracellular domain. To investigate the contribution of each of these domains to the function of the novel receptor, we generated mice with deletions of the individual domains. Mice lacking the intracellular domain are viable and phenotypically normal. Mice lacking the first (N-terminal) Ig domain are also viable and normal, but have a reduced life span. Mice lacking the Ig2 or the Ig3 domain are born alive, but die within 24 â€‹h after birth. Ig2-deficient animals exhibit substantially smaller kidneys than wild-type littermates and contain a lower number of glomeruli. Ig3-deficient mice completely lack metanephric kidneys. Interestingly, both the Ig2 and the Ig3-deficient animals show only minor alterations in the diaphragm, which still enables them to inflate their lungs after birth. Our results demonstrate that the principal function of the FgfrL1 receptor is to control the growth of the metanephric kidneys by regulating nephrogenesis. It appears that this function is primarily accomplished by the Ig3 domain with some contribution of the Ig2 domain. It is conceivable that the two domains interact with an Fgf ligand and another molecule from the surface of neighboring cells to induce condensation of the metanephric mesenchyme to renal epithelia and glomeruli.

Bubble Manipulation Driven by Alternating Current Electrowetting: Oscillation Modes and Surface Detachment.

In this paper, a millimeter-sized bubble in water pending on a substrate is manipulated by applying an alternating current (AC) electric field, known as electrowetting on dielectric. In this setup, standing waves on the bubble surface are observed. The amplitude of these waves varies with frequency, and three resonance peaks (21, 76, and 134 Hz) can be identified. By incorporating the nonlinear friction force for the contact line to an existing surface mode model, a significant improvement to explain the spectrum of the oscillations is obtained, predicting three peak positions, widths, and heights with good accuracy. We also show that bubble detachment correlates with the low-frequency resonance peak. It is found experimentally that if close enough to this peak, then bubbles at sufficiently high voltages are observed to detach from the substrate. This suggests that inertial effects can effectively promote bubble detachment. To confirm this hypothesis, the bubble dynamics is simulated with COMSOL using the full Navier-Stokes equation with a two-phase field and electrostatic stresses. It was found that the bubble experimental detachment process is quite well-reproduced in the simulation, confirming the role of fluid inertia for the detachment process. Given the nice correspondence between the experimental state diagrams and the theoretical modeling, this work contributes to identify a window for precise and reliable bubble manipulation by means of AC electrowetting.

Development and optimization of a microbial co-culture system for heterologous indigo biosynthesis.

BACKGROUND: Indigo is a color molecule with a long history of being used as a textile dye. The conventional production methods are facing increasing economy, sustainability and environmental challenges. Therefore, developing a green synthesis method converting renewable feedstocks to indigo using engineered microbes is of great research and application interest. However, the efficiency of the indigo microbial biosynthesis is still low and needs to be improved by proper metabolic engineering strategies. RESULTS: In the present study, we adopted several metabolic engineering strategies to establish an efficient microbial biosynthesis system for converting renewable carbon substrates to indigo. First, a microbial co-culture was developed using two individually engineered E. coli strains to accommodate the indigo biosynthesis pathway, and the balancing of the overall pathway was achieved by manipulating the ratio of co-culture strains harboring different pathway modules. Through carbon source optimization and application of biosensor-assisted cell selection circuit, the indigo production was improved significantly. In addition, the global transcription machinery engineering (gTME) approach was utilized to establish a high-performance co-culture variant to further enhance the indigo production. Through the step-wise modification of the established system, the indigo bioproduction reached 104.3 mg/L, which was 11.4-fold higher than the parental indigo producing strain. CONCLUSION: This work combines modular co-culture engineering, biosensing, and gTME for addressing the challenges of the indigo biosynthesis, which has not been explored before. The findings of this study confirm the effectiveness of the developed approach and offer a new perspective for efficient indigo bioproduction. More broadly, this innovative approach has the potential for wider application in future studies of other valuable biochemicals' biosynthesis.

Total in vitro biosynthesis of the nonribosomal macrolactone peptide valinomycin.

Natural products are important because of their significant pharmaceutical properties such as antiviral, antimicrobial, and anticancer activity. Recent breakthroughs in DNA sequencing reveal that a great number of cryptic natural product biosynthetic gene clusters are encoded in microbial genomes, for example, those of Streptomyces species. However, it is still challenging to access compounds from these clusters because many source organisms are uncultivable or the genes are silent during laboratory cultivation. To address this challenge, we develop an efficient cell-free platform for the rapid, in vitro total biosynthesis of the nonribosomal peptide valinomycin as a model. We achieve this goal in two ways. First, we used a cell-free protein synthesis (CFPS) system to express the entire valinomycin biosynthetic gene cluster (>19 kb) in a single-pot reaction, giving rise to approximately 37 µg/L of valinomycin after optimization. Second, we coupled CFPS with cell-free metabolic engineering system by mixing two enzyme-enriched cell lysates to perform a two-stage biosynthesis. This strategy improved valinomycin production ~5000-fold to nearly 30 mg/L. We expect that cell-free biosynthetic systems will provide a new avenue to express, discover, and characterize natural product gene clusters of interest in vitro.

Exosomal LncRNA-NEAT1 derived from MIF-treated mesenchymal stem cells protected against doxorubicin-induced cardiac senescence through sponging miR-221-3p.

BACKGROUND: The chemotherapy drug doxorubicin (Dox) is widely used for treating a variety of cancers. However, its high cardiotoxicity hampered its clinical use. Exosomes derived from stem cells showed a therapeutic effect against Dox-induced cardiomyopathy (DIC). Previous studies reported that exosomes derived from mesenchymal stem cells (MSCs) pretreated with macrophage migration inhibitory factor (MIF) (exosomeMIF) showed a cardioprotective effect through modulating long noncoding RNAs/microRNAs (lncRNAs/miRs). This study aimed to investigate the role of exosomeMIF in the treatment of DIC. RESULTS: Exosomes were isolated from control MSCs (exosome) and MIF-pretreated MSCs (exosomeMIF). Regulatory lncRNAs activated by MIF pretreatment were explored using genomics approaches. Fluorescence-labeled exosomes were tracked in vitro by fluorescence imaging. In vivo and in vitro, miR-221-3p mimic transfection enforced miR-221-3p overexpression, and senescence-associated ß-galactosidase assay was applied to test cellular senescence. Exosomal delivering LncRNA-NEAT1 induced therapeutic effect in vivo was confirmed by echocardiography. It demonstrated that exosomesMIF recovered the cardiac function and exerted the anti-senescent effect through LncRNA-NEAT1 transfer against Dox. TargetScan and luciferase assay showed that miR-221-3p targeted the Sirt2 3'-untranslated region. Silencing LncRNA-NEAT1 in MSCs, miR-221-3p overexpression or Sirt2 silencing in cardiomyocytes decreased the exosomeMIF-induced anti-senescent effect against Dox. CONCLUSIONS: The results indicated exosomeMIF serving as a promising anti-senescent effector against Dox-induced cardiotoxicity through LncRNA-NEAT1 transfer, thus inhibiting miR-221-3p and leading to Sirt2 activation. The study proposed that exosomeMIF might have the potential to serve as a cardioprotective therapeutic agent during cancer chemotherapy.

Distally Based Sural Adipofascial Turnover Flap for Coverage of Complicated Wound in the Foot and Ankle Region.

BACKGROUNDS: Distally based perforator propeller flap from the lower leg region is a versatile local reconstructive technique for the foot and ankle defects. However, flap venous congestion remains a tough nut to crack. We hypothesize that raising an adipofascial flap with turnover mode of transposition can improve venous drainage and enhance flap safety. METHODS: Based on the 2 rows of septocutaneous perforators in the posterior distal third of the lower leg, distally based adipofascial flap was raised from medial sural region nourished by 1 perforator bundle from the posterior tibial artery or from the lateral sural region from the peroneal artery. The superficial dissection was performed in subdermal plane and deep in to the subfascial space. The flap was nourished by perforator-plus-adipofascial pedicle and turned over 180 degrees upside down to reach the distal wounds. One week later, a split-skin graft was used to cover the exposed fascial flap. Postoperatively, flap survival, complications, and patient functional recovery were evaluated. RESULTS: Distally based sural turnover adipofascial flaps were used in 12 cases with complicated wounds of the distal third lower leg, foot, and ankle region. All wounds were caused by trauma and experienced fracture implants fixation and 5 with osteomyelitis. The comorbidities include diabetes in 9 cases and smoking in 7. There were 8 medial ural flaps and 4 lateral sural flaps. The adipofiscial flaps measured from 6.0 cm × 5.0 cm to 17.0 cm × 6.0 cm (mean, 61.3 cm). Postoperatively, all flaps survived uneventfully without any complication such as flap ischemia and/or necrosis. Two minor donor site complications were encountered, one was postoperative hematoma, and another was hyperproliferative scar. After a mean of 14.6 months of follow-up, the adipofascial flap plus skin graft showed a durable esthetic coverage, with normal shoe wearing and walking. CONCLUSIONS: Distally based sural adipofascial turnover flap is a simple and reliable wound coverage technique. It avoids venous congestion as usually seen in distally based fasciocutaneous flaps.

Evolution of the fusogenic activity of the receptor FGFRL1.

FGFRL1 is a transmembrane receptor that can induce the fusion of CHO cells to multinucleated syncytia. This cell fusion activity has been attributed to the extracellular Ig3 domain of the receptor. We investigated how the fusogenic activity evolved during the evolution of animals. We found that the Ig3 domain from humans, mice, chicken and fish stimulates fusion of CHO cells, while the Ig3 domain from lancelet and sea urchin does not. It is therefore conceivable that the fusogenic activity of FGFRL1 developed during the evolution of vertebrates. Bony fish contain two copies of the FGFRL1 gene because they have undergone a whole-genome duplication. One of the corresponding proteins (FGFRL1a) induces cell-cell fusion, while the other (FGFRL1b) does not. Analysis of chimeric constructs and in vitro mutagenesis suggested that FGFRL1b has lost its fusogenic activity after duplication. A rescue experiment supported this conclusion. When four amino acids were changed, the Ig3 domain of FGFRL1b was converted into an active, fusogenic protein comparable to FGFRL1a. The four amino acids are located in a hydrophobic pocket of the Ig3 domain. It is likely that this hydrophobic pocket interacts with a target molecule on the membrane of adjacent cells to induce cell-cell fusion.