Topological electronic states in holey graphyne.

We unveil that the holey graphyne (HGY), a two-dimensional carbon allotrope where benzene rings are connected by two -C≡C- bonds fabricated recently in a bottom-up way, exhibits topological electronic states. Using first-principles calculations and Wannier tight-binding modeling, we discover a higher-order topological invariant associated withC2symmetry of the material, and show that the resultant corner modes appear in nanoflakes matching to the structure of precursor reported previously, which are ready for direct experimental observations. In addition, we find that a band inversion between emergentg-like andh-like orbitals gives rise to a nontrivial topology characterized byZ2invariant protected by an energy gap as large as 0.52 eV, manifesting helical edge states mimicking those in the prominent quantum spin Hall effect, which can be accessed experimentally after hydrogenation in HGY. We hope these findings trigger interests towards exploring the topological electronic states in HGY and related future electronics applications.

Heterologous Expression and Characterization of a pH-Stable Chitinase from Micromonospora aurantiaca with a Potential Application in Chitin Degradation.

To promote the bioconversion of marine chitin waste into value-added products, we expressed a novel pH-stable Micromonospora aurantiaca-derived chitinase, MaChi1, in Escherichia coli and subsequently purified, characterized, and evaluated it for its chitin-converting capacity. Our results indicated that MaChi1 is of the glycoside hydrolase (GH) family 18 with a molecular weight of approximately 57 kDa, consisting of a GH18 catalytic domain and a cellulose-binding domain. We recorded its optimal activity at pH 5.0 and 55 °C. It exhibited excellent stability in a wide pH range of 3.0-10.0. Mg2+ (5 mM), and dithiothreitol (10 mM) significantly promoted MaChi1 activity. MaChi1 exhibited broad substrate specificity and hydrolyzed chitin, chitosan, cellulose, soluble starch, and N-acetyl chitooligosaccharides with polymerization degrees ranging from three to six. Moreover, MaChi1 exhibited an endo-type cleavage pattern, and it could efficiently convert colloidal chitin into N-acetyl-D-glucosamine (GlcNAc) and (GlcNAc)2 with yields of 227.2 and 505.9 mg/g chitin, respectively. Its high chitin-degrading capacity and exceptional pH tolerance makes it a promising tool with potential applications in chitin waste treatment and bioactive oligosaccharide production.

Efficacy and safety of fibrin sealant application in patients undergoing thyroidectomy: a systematic review and meta-analysis.

Various studies have focused on the application of fibrin sealants (FS) in thyroid surgery. Utilizing a meta-analysis, this systematic review analyzed the findings of recent randomized controlled trials on the safety and efficacy of FS in patients who underwent thyroidectomy. The Cochrane Library, Web of Science, Embase, PubMed, and Medline databases were searched for relevant studies, without any language restrictions. Seven randomized controlled trials were included in the originally identified 69 studies. Overall, 652 patients received FS during thyroid surgery; their outcomes were compared with those of conventionally treated patients. The primary outcomes were total volume of wound drainage, length of hospitalization, and operative time. Significant differences were observed in the total volume of wound drainage (mean deviation (MD): -29.75, 95% confidence interval (CI): -55.39 to -4.11, P = 0.02), length of hospitalization (MD: -0.84, 95% CI: -1.02 to -0.66, P < 0.00001), and surgery duration (MD: -7.60, 95% CI: -14.75 to -0.45, P = 0.04). Secondary outcomes were seroma and hypoparathyroidism development. The risk of hypoparathyroidism did not differ between the FS and conventional groups (I = 0%, relative risk = 1.31, P = 0.38). Analysis of "seroma formation that required invasive treatment" indicated that FS showed some benefit (I2 = 8%, relative risk 0.44, P = 0.15). Heterogeneity among the different trials limited their conclusions. The meta-analysis showed that although FS use did not significantly reduce seroma or hypoparathyroidism incidence in patients after thyroidectomy, it significantly reduced the total drainage volume, length of hospitalization, and duration of surgery.

Wheat bran arabinoxylans: Chemical structure, extraction, properties, health benefits, and uses in foods.

Wheat bran (WB) is a well-known and valuable source of dietary fiber. Arabinoxylan (AX) is the primary hemicellulose in WB and can be isolated and used as a functional component in various food products. Typically, AX is extracted from the whole WB using different processes after mechanical treatments. However, WB is composed of different layers, namely, the aleurone layer, pericarp, testa, and hyaline layer. The distribution, structure, and extractability of AX vary within these layers. Modern fractionation technologies, such as debranning and electrostatic separation, can separate the different layers of WB, making it possible to extract AX from each layer separately. Therefore, AX in WB shows potential for broader applications if it can be extracted from the different layers separately. In this review, the distribution and chemical structures of AX in WB layers are first discussed followed by extraction, physicochemical properties, and health benefits of isolated AX from WB. Additionally, the utilization of AX isolated from WB in foods, including cereal foods, packaging film, and the delivery of food ingredients, is reviewed. Future perspectives on challenges and opportunities in the research field of AX isolated from WB are highlighted.

[Molecular identification of animal species of Bufonis Venenum from secretions].

The animal species is one of the key factors affecting the quality of Bufonis Venenum. The quality of Bufonis Venenum derived from Bufo bufo gargarizans is significantly higher than that from B. melanostictus. Since Bufonis Venenum is from secretions, the conventional identification methods are difficult to identify the animal species due to the lack of the appearance and morphology of the animals. The rapid development of molecular identification technology has provided new methods for the identification of Bufonis Venenum. However, because of the low content and serve degradation of residual DNA in secretions, the research on the molecular identification of Chinese medicinal materials from secretions remains to be carried out. To understand the animal species of Bufonis Venenum, this study collected 83 samples of Bufonis Venenum, including 7 commercially available samples, 5 reference medicinal materials, and 71 animal samples from which Bufonis Venenum was prepared according to the method in the 2020 edition of the Chinese Pharmacopoeia. Different DNA extraction methods were used and compared, and the mitochondrial 16S rRNA gene fragments were amplified, on the basis of which the phylogenetic trees were built. Finally, molecular identification of the animal species of the samples was performed. The results showed that the DNA extracted from Bufonis Venenum by the reagent kit had good quality, and 16S rRNA sequences were successfully amplified from 80 out of the 83 samples. In addition, 71 16S rRNA sequences of the animal species of Bufonis Venenum were downloaded from GenBank. The phylogenetic trees constructed based on the neighbor-joining(NJ) method and the Bayesian inference(BI) method showed that the samples derived from B. bufo gargarizans and B. melanostictus were clustered into separate monophyletic clades, with the support of 100%(NJ) and 1.00(BI), respectively. The animal species of both commercially available samples and reference medicinal materials were B. bufo gargarizans. In conclusion, DNA can be extracted from Bufonis Venenum derived from secretions, and the 16S rRNA gene sequences can be amplified, which can be used for molecular identification of the animal species of Bufonis Venenum. The findings provide a reference for the quality control of Bufonis Venenum and the identification of animal species of medicinal materials derived from secretions.

Routine image-enhanced endoscopic surveillance for metachronous esophageal squamous cell neoplasms in head and neck cancer patients.

BACKGROUND: Esophageal squamous cell neoplasms (ESCNs) are common second primary tumors in patients with head and neck cancer. Image-enhanced endoscopy (IEE) with Lugol chromoendoscopy or magnifying narrow-band imaging both increase the detection of early ESCNs. No evidence-based ESCN surveillance program for head and neck cancer patients without a history of synchronous ESCNs exists. We aimed to evaluate the performance of an IEE surveillance program with magnifying narrow-band imaging endoscopy and Lugol chromoendoscopy. METHODS: From April 2016, we routinely used IEE with magnifying narrow-band imaging and Lugol chromoendoscopy to evaluate patients with head and neck cancer history. All patients who were negative for ESCNs at the first surveillance endoscopy and received at least 2 IEEs through December 2019 were included. Demographic profiles, clinical data, cancer characteristics, IEE results and pathology reports were analyzed. RESULTS: A total of 178 patients were included. Only 4 patients (2.2%) developed metachronous ESCNs during follow-up, all of whom received curative resection treatment. The interval for the development of metachronous ESCNs was 477 to 717 days. In multivariate Firth logistic regression and Kaplan‒Meier survival curve analysis, Lugol's voiding lesion type C had an increased risk of esophageal cancer development (adjusted odds ratio = 15.71; 95% confidence interval, 1.33-185.87, p = 0.029). Eight patients died during the study period, and none of them had metachronous ESCNs. CONCLUSIONS: IEE with magnifying narrow-band imaging and Lugol chromoendoscopy is an effective surveillance program in head and neck cancer patients without a history of ESCNs. Annual surveillance can timely detect early ESCNs with low ESCN-related mortality.

Sharing of Moonlighting Proteins Mediates the Symbiotic Relationship among Intestinal Commensals.

The human gastrointestinal tract is inhabited by trillions of symbiotic bacteria that form a complex ecological community and influence human physiology. Symbiotic nutrient sharing and nutrient competition are the most studied relationships in gut commensals, whereas the interactions underlying homeostasis and community maintenance are not fully understood. Here, we provide insights into a new symbiotic relationship wherein the sharing of secreted cytoplasmic proteins, called "moonlighting proteins," between two heterologous bacterial strains (Bifidobacterium longum and Bacteroides thetaiotaomicron) was observed to affect the adhesion of bacteria to mucins. B. longum and B. thetaiotaomicron were cocultured using a membrane-filter system, and in this system the cocultured B. thetaiotaomicron cells showed greater adhesion to mucins compared to that shown by monoculture cells. Proteomic analysis showed the presence of 13 B. longum-derived cytoplasmic proteins on the surface of B. thetaiotaomicron. Moreover, incubation of B. thetaiotaomicron with the recombinant proteins GroEL and elongation factor Tu (EF-Tu)-two well-known mucin-adhesive moonlighting proteins of B. longum-led to an increase in the adhesion of B. thetaiotaomicron to mucins, a result attributed to the localization of these proteins on the B. thetaiotaomicron cell surface. Furthermore, the recombinant EF-Tu and GroEL proteins were observed to bind to the cell surface of several other bacterial species; however, the binding was species dependent. The present findings indicate a symbiotic relationship mediated by the sharing of moonlighting proteins among specific strains of B. longum and B. thetaiotaomicron. IMPORTANCE The adhesion of intestinal bacteria to the mucus layer is an important colonization strategy in the gut environment. Generally, the bacterial adhesion process is a characteristic feature of the individual cell surface-associated adhesion factors secreted by a particular bacterium. In this study, coculture experiments between Bifidobacterium and Bacteroides show that the secreted moonlighting proteins adhere to the cell surface of coexisting bacteria and alter the adhesiveness of the bacteria to mucins. This finding indicates that the moonlighting proteins act as adhesion factors for not only homologous strains but also for coexisting heterologous strains. The presence of a coexisting bacterium in the environment can significantly alter the mucin-adhesive properties of another bacterium. The findings from this study contribute to a better understanding of the colonization properties of gut bacteria through the discovery of a new symbiotic relationship between them.

Diversity and Evolution of Iron Uptake Pathways in Marine Cyanobacteria from the Perspective of the Coastal Strain Synechococcus sp. Strain PCC 7002.

Marine cyanobacteria contribute to approximately half of the ocean primary production, and their biomass is limited by low iron (Fe) bioavailability in many regions of the open seas. The mechanisms by which marine cyanobacteria overcome Fe limitation remain unclear. In this study, multiple Fe uptake pathways have been identified in a coastal strain of Synechococcus sp. strain PCC 7002. A total of 49 mutants were obtained by gene knockout methods, and 10 mutants were found to have significantly decreased growth rates compared to the wild type (WT). The genes related to active Fe transport pathways such as TonB-dependent transporters and the synthesis and secretion of siderophores are found to be essential for the adaptation of Fe limitation in Synechococcus sp. PCC 7002. By comparing the Fe uptake pathways of this coastal strain with other open-ocean cyanobacterial strains, it can be concluded that the Fe uptake strategies from different cyanobacteria have a strong relationship with the Fe bioavailability in their habitats. The evolution and adaptation of cyanobacterial iron acquisition strategies with the change of iron environments from ancient oceans to modern oceans are discussed. This study provides new insights into the diversified strategies of marine cyanobacteria in different habitats from temporal and spatial scales. IMPORTANCE Iron (Fe) is an important limiting factor of marine primary productivity. Cyanobacteria, the oldest photosynthetic oxygen-evolving organisms on the earth, play crucial roles in marine primary productivity, especially in the oligotrophic ocean. How they overcome Fe limitation during the long-term evolution process has not been fully revealed. Fe uptake mechanisms of cyanobacteria have been partially studied in freshwater cyanobacteria but are largely unknown in marine cyanobacterial species. In this paper, the characteristics of Fe uptake mechanisms in a coastal model cyanobacterium, Synechococcus sp. PCC 7002, were studied. Furthermore, the relationship between Fe uptake strategies and Fe environments of cyanobacterial habitats has been revealed from temporal and spatial scales, which provides a good case for marine microorganisms adapting to changes in the marine environment.

Microstructures of Starch Granules with Different Amylose Contents and Allomorphs as Revealed by Scattering Techniques.

In this study, as-is (ca. 12% moisture by mass) and hydrated (50% water by mass) granules of waxy potato (WP), waxy wheat (WW), waxy maize, normal maize, and high-amylose maize (HAM) starches were investigated by using small-angle neutron and X-ray scattering (SANS and SAXS), wide-angle X-ray scattering, and ultra-small-angle neutron scattering. The SANS and SAXS data were fitted using the two-phase stacking model of alternating crystalline and amorphous layers. The partial crystalline lamellar structures inside the growth rings of granules were analyzed based on the inter-lamellar distances, thicknesses of the crystalline lamellae and amorphous layers, thickness polydispersities, and water content in each type of layer. Despite having a longer average chain length of amylopectin, the WP and HAM starches, which had B-type allomorph, had a shorter inter-lamellar distance than the other three starches with A-type allomorph. The WP starch had the most uniform crystalline lamellar thickness. After hydration, the amorphous layers were expanded, resulting in an increase of inter-layer distance. The low-angle intensity upturn in SANS and SAXS was attributed to scattering from interfaces/surfaces of larger structures, such as growth rings and macroscopic granule surfaces. Data analysis methods based on model fitting and 1D correlation function were compared. The study emphasized─owing to inherent packing disorder inside granules─that a comprehensive analysis of different parameters was essential in correlating the microstructures with starch properties.

Wheat bran layers: composition, structure, fractionation, and potential uses in foods.

Wheat bran, the main by-product of dry milling of wheat, is currently mainly used in the animal feed industry, but has attracted attention as a food ingredient owing to its high dietary fiber and phytochemical contents, providing excellent physiological effects. The bran layers (aleurone layer, outer pericarp and intermediate layer) contain different compositions, structures, and nutrients, and have different properties. Each layer, when separated and isolated, potentially could find more extensive applications in foods. This triggered interest in isolating the bran layers using milling and wet- or dry-fractionation techniques based on their chemical or physical properties. The recent progress has allowed the production of commercial products from wheat bran layers, particularly aleurone-rich products, enhancing the value of wheat bran layers and their applications in food. The present review highlights the recent advances in studying the chemical composition including distribution of chemical components, physical structure, biopolymer matrix, and physicochemical properties of each wheat bran layer. Technologies to fractionate wheat bran layers and utilization of different bran layers in foods are discussed and reviewed, providing new strategies for improving the value of wheat bran and utilization of wheat bran in foods.

(±)-Salvicatone A: A Pair of C27-Meroterpenoid Enantiomers with Skeletons from the Roots and Rhizomes of Salvia castanea Diels f. tomentosa Stib.

(±)-Salvicatone A (1), a C27-meroterpenoid featuring a unique 6/6/6/6/6-pentacyclic carbon skeleton with a 7,8,8a,9,10,10a-hexahydropyren-1 (6H)-one motif, was isolated from the roots and rhizomes of Salvia castanea Diels f. tomentosa Stib. Its structure was characterized by comprehensive spectroscopic analyses along with computer-assisted structure elucidation, including ACD/structure elucidator and quantum chemical calculations with 1H/13C NMR and electronic circular dichroism. Biogenetically, compound 1 was constructed from decarboxylation following [4 + 2] Diels-Alder cycloaddition reaction between caffeic acid and miltirone analogue. Bioassays showed that (-)-1 and (+)-1 inhibited nitric oxide production in lipopolysaccharide-induced RAW264.7 macrophage cells with an IC50 value of 6.48 ± 1.25 and 15.76 ± 5.55 µM, respectively. The structure-based virtual screening based on the pharmacophores in ePharmaLib, as well as the molecular docking and molecular dynamics simulations study, implied that (-)-1 and (+)-1 may potentially bind to retinoic acid receptor-related orphan receptor C to exert anti-inflammatory activities.

Effects of demineralization mode and particle size of allogeneic bone powder on its physical and chemical properties.

At present, the commonly used allogeneic bone powder in the clinic can be divided into nondemineralized bone matrix and demineralized bone matrix (DBM). Commonly used demineralizers include acids and ethylene diamine tetraacetic acid (EDTA). There may be some diversities between them. Also, the size of the bone particle can affects its cell compatibility and osteogenic ability. We produced different particle sizes i.e., < 75, 75-100, 100-315, 315-450, 450-650, and 650-1000 µm, and treated in three ways (nondemineralized, demineralized by EDTA, and demineralized by HCl). Scanning electron microscopy showed that the surface of the samples in each group was relatively smooth without obvious differences. The results of specific surface area and porosity analysis showed that they were significantly higher in demineralized bone powder than in nondemineralized bone powder, however, there was no significant difference between the two decalcification methods. The content of hydroxyproline in nondemineralized bone powder and EDTA-demineralized bone powder had no statistical difference, while HCl-demineralization had statistical significance compared with the former two, and the content increased with the decrease of particle size. The protein and BMP-2 extracted from HCl demineralized bone powder were significantly higher than that from nondemineralized bone powder and EDTA demineralized bone powder, and there were differences among different particle sizes. These results suggested the importance of demineralization mode and particle size of the allogenic bone powder and provided guidance for the choice of the most appropriate particle size and demineralization mode to be used in tissue bioengineering.

Repair of tendons treated with peracetic acid-ethanol and gamma irradiation by EDC combined with NHS: a morphological, biochemical and biomechanical study in vitro.

The purpose of this study was to investigate whether 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) combined with n-hydroxysuccinimide (NHS) can repair tendon damage caused by peracetic acid-ethanol and gamma irradiation sterilization. The semitendinosus tendons of 15 New Zealand white rabbits were selected as experimental materials, and the tendons were sterilized in a solution containing 1% (v/w) peracetic acid and 24% (v/w) ethanol. After 15 kGy gamma irradiation sterilization, the tendons were randomly divided into three groups (n = 10). The tendons were repaired with EDCs of 0, 2.5 and 5 mM combined with 5 mM NHS for 6 h, the tendons were temporarily stored at - 80 ± °C. The arrangement and spatial structure of collagen fibers were observed by light microscopy and scanning electron microscopy, the collagen type and collagen crimp period were observed under a polarizing microscope, and the collagen fibril diameter and its distribution were measured by transmission electron microscopy, from which the collagen fibril index and mass average diameter were calculated. The resistance of collagen to enzymolysis was detected by the free hydroxyproline test, and tensile fracture and cyclic loading tests of each group of tendons were carried out, from which the elastic modulus, maximum stress, maximum strain, strain energy density and cyclic creep strain were calculated. The obtained results showed that the gap between loose collagen fibers in the 0 mM control group was wider, the parallel arrangement of tendons in the 2.5 and 5 mM groups was more uniform and regular and the fiber space decreased, the crimp period in the 5 mM group was lower than that in the 0 mM group (P < 0.05), and the concentration of hydroxyproline in the 5 mM group (711.64 ± 77.95 µg/g) was better than that in the control group (1150.57 ± 158.75 µg/g). The elastic modulus of the 5 mM group (424.73 ± 150.96 MPa) was better than that of the 0 mM group (179.09 ± 37.14 MPa). Our results show that EDC combined with NHS can repair damaged tendons after peracetic acid-ethanol and gamma radiation treatment, and 5 mM EDC has better morphological performance, anti-enzymolysis ability and biomechanical properties than 2.5 mM EDC.

Comparison of demineralized bone matrix with different cycling crushing times in posterolateral fusion model of athymic rats.

Decalcified bone matrix (DBM) is a widely used alternative material for bone transplantation. In the DBM production process, an effective particle size and the highest utilization rate of raw materials can be achieved only through multiple high-speed circulating comminution. The rat posterolateral lumbar fusion model (PLF) is the most mature small animal model for the initial evaluation of the efficacy of graft materials for bone regeneration and spinal fusion. To evaluate the differences in the in vivo osteogenic effects of DBM pulverization through 1, 5, 9, and 14 high-speed cycles, sixty athymic rats were divided into six groups: single cycling crushing (CC1), 5 cycles of crushing (CC5), 9 cycles of crushing (CC9), 13 cycles of crushing (CC13), autogenous bone graft (ABG) and negative control (NC). Posterolateral lumbar fusion was performed. Six weeks after surgery, the bilateral lumbar fusion of athymic rats was evaluated through manual palpation, X-ray, micro-CT and histological sections. Rank data were tested by the rank-sum test, and nonparametric data were tested by the Kruskal‒Wallis H test. The manual palpation and X-ray results showed that the fusion rate did not significantly differ between the CC1, CC5, CC9, CC13 and ABG groups. However, cavities appeared in CC9 and CC13 on the micro-CT image. The bone mass (BV/TV) of CC1, CC5, CC9 and CC13 was better than that of the ABG group, while almost no osteogenesis was observed in the NC group. Histologically, there was no obvious difference between the four groups except that the CC9 group and CC13 group had more fibrous tissues in the new bone. In conclusion, DMB with different cycling crushing times has no obvious difference in fusion rate of PLF, but it is slightly better than the ABG group.

LncRNA MIR155HG functions as a ceRNA of miR-223-3p to promote cell pyroptosis in human degenerative NP cells.

Nucleus pulposus (NP) cell pyroptosis plays a critical role in the pathogenesis of intervertebral disk degeneration (IDD). MIR155 host gene (MIR155HG) is a long non-coding RNA with pro-inflammatory activity. However, very little is known about its role in NP cell pyroptosis. This study aimed to observe the impact of MIR155HG on cell pyroptosis and to explore the underlying mechanism in human degenerative NP cells. Our results demonstrated that MIR155HG expression was significantly increased in human degenerative NP tissue samples and showed a positive correlation with Pfirrmann score. Overexpression of MIR155HG through a lentiviral vector decreased miR-223-3p levels, up-regulated NLRP3 expression and induced cell pyroptosis in human degenerative NP cells. A ceRNA action mode was identified among MIR155HG, miR-223-3p, and NLRP3. The stimulatory effect of MIR155HG on human degenerative NP cell pyroptosis was significantly reversed by pretreatment with miR-223-3p mimic or NLRP3 siRNA. In summary, these data suggest that MIR155HG sponges miR-223-3p to promote NLRP3 expression, leading to induction of cell pyroptosis in human degenerative NP cells. Targeting MIR155HG could be a novel and promising strategy to slow down the progression of IDD.

Extraction of non-starch lipid from protease-treated wheat flour.

BACKGROUND: Lipids account for 2.0-2.5% of wheat flour by dry weight and affect properties and quality of cereal foods. A new method was developed to extract non-starch lipids from wheat flour. Wheat flour was first hydrolyzed with a protease and followed by extraction of non-starch lipids by water-saturated butanol (WSB). RESULT: Protein hydrolysis by protease followed by extraction of non-starch lipids with WSB increased yield to 1.9 ± 0.3% from 1.0 ± 0.1% with no protease treatment. The lipid profile showed a significant increase in phospholipid compounds extracted with protease hydrolysis (5.9 ± 0.8 nmol·g-1 ) versus without enzymatic treatment (2.4 ± 1.3 nmol g-1 ). CONCLUSION: Improved lipid extraction yield and phospholipid compounds following protease-assisted extraction method provided additional insight towards the understanding of protein-lipid interaction in wheat flour. The new protease-assisted extraction method may be applied to analyzing non-starch lipids in other types of wheat flours and other cereal flours. © 2021 Society of Chemical Industry.

[A new norsesquiterpenoid from Schisandra chinensis].

This study investigated the chemical components from the leaves and stems of Schisandra chinensis. Three norsesquiterpenoids were isolated from S. chinensis by various column chromatographies(silica gel, Sephadex LH-20, and MCI), reversed-phase medium-pressure preparative, and semi-preparative high-performance liquid chromatography(HPLC). Their structures were identified based on physicochemical properties, mass spectrometry(MS), nuclear magnetic resonance(NMR), ultraviolet(UV), and electro-nic circular dichroism(ECD) as(3R,4R,5R,6S,7E)-3,4,5,6-tetrahydroxy-7-megastigmen-9-one(1),(3S,5R,6R,7E)-3,5,6-trihydroxy-7-megastigmen-9-one(2), and(3S,4R,9R)-3,4,9-trihydroxymegastigman-5-ene(3). Compound 1 was a new compound, and its absolute configuration was determined by ECD. Compounds 2 and 3 were isolated from the Schisandra plant for the first time.

A novel tool for predicting the survival of endoprosthesis used for reconstruction of the knee following tumor resection: a retrospective cohort study.

BACKGROUND: Prosthesis-related complications, after knee reconstruction with endoprosthesis during operation for tumors around the knee, remain an unresolved problem which necessitate a revision or even an amputational surgery. The purpose of the current study was to identify significant risk factors associated with implant failure, and establish a novel model to predict survival of the prosthesis in patients operated with endoprostheses for tumor around knee. METHODS: We retrospectively reviewed the clinical database of our institution for patients who underwent knee reconstruction due to tumors. A total of 203 patients were included, including 123 males (60.6%) and 80 (39.4%) females, ranging in age from 14 to 77 years (mean: 34.3 ± 17.3 years). The cohort was randomly divided into training (n = 156) and validation (n = 47) samples. Univariable COX analysis was used for initially identifying potential independent predictors of prosthesis survival with the training group (p < 0.150). Multivariate COX proportional hazard model was selected to identify final significant prognostic factors. Using these significant predictors, a graphic nomogram, and an online dynamic nomogram were generated for predicting the prosthetic survival. C-index and calibration curve were used for evaluate the discrimination ability and accuracy of the novel model, both in the training and validation groups. RESULTS: The 1-, 5-, and 10-year prosthetic survival rates were 94.0, 90.8, and 83.0% in training sample, and 96.7, 85.8, and 76.9% in validation sample, respectively. Anatomic sites, length of resection and length of prosthetic stem were independently associated with the prosthetic failure according to multivariate COX regression model (p<0.05). Using these three significant predictors, a graphical nomogram and an online dynamic nomogram model were generated. The C-indexes in training and validation groups were 0.717 and 0.726 respectively, demonstrating favourable discrimination ability of the novel model. And the calibration curve at each time point showed favorable consistency between the predicted and actual survival rates in training and validation samples. CONCLUSIONS: The length of resection, anatomical location of tumor, and length of prosthetic stem were significantly associated with prosthetic survival in patients operated for tumor around knee. A user-friendly novel online model model, with favorable discrimination ability and accuracy, was generated to help surgeons predict the survival of the prosthesis.

Genome-wide association study reveals the genes associated with the leaf inclusion contents in Chinese medical tree Eucommia ulmoides.

Eucommia ulmoides is an economic tree that can biosynthesize secondary metabolites with pharmacological functions. Genetic basis of biosynthesis of these compounds is almost unknown. Therefore, genomic-wide association study was performed to exploit the genetic loci maybe involved in biosynthetic pathways of 5 leaf inclusions (aucubin, chlorogenic acid, gutta-percha, polyphenols, total flavonoids). It was shown that contents of the 5 leaf metabolites have a wide variation following normal distribution. A total of 2 013 102 single nucleotide polymorphism (SNP) markers were identified in a population containing 62 individual clones. Through genome-wide association study analysis, many SNP loci were identified perhaps associated with phenotypes of the leaf inclusions. Higher transcriptional levels of the candidate genes denoted by significant SNPs in leaves suggested they may be involved in biosynthesis of the leaf inclusions. These genetic loci provide with invaluable information for further studies on the gene functions in biosynthesis of the leaf inclusions and selective breeding of the plus trees.

Comparative assessment of biomechanics induced by hinge knee prostheses with two different motion axial system.

We aimed to evaluate the biomechanical contact characteristics of rotating hinge knee (RHK) prostheses with different motion axial systems. We performed finite element (FE) analyses to investigate and compare the peak contact stress and contact location on tibial insert and bushing during a gait cycle. The biaxial (BA) system and spherical center axial (SA) system RHK prostheses were included in this study. The comparisons between experimental tests and FE analyses were performed to verify the validation of FE models. Decreased ISO loadings were then applied to the validated FE models to investigate the peak contact stress and contact location on tibial insert and bushing. The contact areas obtained from experimental tests and FE analyses were in a good agreement. The peak contact stresses on tibial insert and bushing of BA prosthesis were higher than those of SA prosthesis. The contact locations on the superior surface of tibial insert in SA and BA prostheses were at the middle-posterior and posterior side, while those on the rotating axial surface were at the medial and lateral sides, respectively. This study indicate that the tibial insert and bushing of an SA prosthesis have lower peak contact stresses and better contact locations than those of a BA prosthesis during a gait cycle, which may decrease the risk of long-term complications of RHK prostheses. Future studies should be performed to confirm the relationship between the contact characteristics and wear in RHK prostheses.