Fine mapping of ClLOX, a QTL for powdery mildew resistance in watermelon (Citrullus lanatus L.).

KEY MESSAGE: ClLOX, is located on chromosome 2 and encodes a lipoxygenase gene, which induced watermelon powdery mildew resistance by inhibiting pathogen spread. Powdery mildew is one of the most severe fungal diseases reducing yield and quality of watermelon (Citrullus lanatus L.) and other cucurbit crops. Genes responsible for powdery mildew resistance in watermelon are highly valuable. In this study, we first identified the QTL pm-lox for powdery mildew resistance in watermelon, located within a 0.93 Mb interval of chromosome 2, via XP-GWAS method using two F2 populations. The F2:3 families from one of the F2 populations were then used for fine-mapping the pm-lox locus into a 9,883 bp physical region between 29,581,906 and 29,591,789, containing only two annotated genes. Of these, only ClG42_02g0161300 showed a significant differential expression between the resistant and susceptible lines after powdery mildew inoculation based on RNA sequencing (RNA-seq) and qRT-PCR analysis, and is designated ClLOX. Derived Cleaved Amplified Polymorphic Sequence (dCAPs) markers were developed and validated. In addition, our tests showed that the resistance was anti-spread rather than anti-infection of the pathogen. This study identified a new resistance gene (ClLOX), provided insights into the mechanism of powdery mildew resistance, and developed a molecular marker for watermelon breeding.

Real-time ghost imaging algorithm on the multidimensional vector matrix Walsh transformation with spatiotemporal free-fps.

In this research, we propose a real-time spatiotemporal free-fps algorithm based on the multidimensional vector matrix Walsh transform with an adjustable ghost imaging video quality and a frame rate to address the issues of uneven imaging speed, fixed imaging frame rate, and uncomfortable appearance in real-time ghost imaging videos of moving objects. This algorithm utilizes the temporal and spatial correlation of ghost imaging videos to achieve free and adjustable video frame rates in time without being limited by DMD refresh rates. Improving the spatial information of a single frame in space enhances the smoothness of ghost imaging videos, making the appearance of ghost imaging videos more comfortable. To achieve this, a four-dimensional vector Walsh transform kernel matrix is used to transform and reconstruct the high-quality images of the target object. Then the reconstructed high-quality image is spatially interpolated to enhance spatial information. Reasonable frame rate parameters are set based on the corresponding relationship between the detection values of the adjacent frames and speckle, improving the ghost imaging video in both time and space and achieving a smooth real-time ghost imaging video with an adjustable quality and frame rate. The simulation and experimental results of moving objects show that our algorithm solves the limitation of a DMD refresh rate compared with the existing ghost imaging video methods and makes the ghost imaging video more comfortable and smoother in real time. The PSNR of the objective evaluation index is increased by 12%. Regarding a subjective evaluation, this paper proposes an adaptive parameterless evaluation algorithm (APEA) for images with different resolutions based on the NRSS, which improved the structure retention degree by 13% and the Brisque parameter evaluation by 70%. We propose an adaptive parameterless video comfort evaluation algorithm (APVCEA) to evaluate the subjective comfort of ghost imaging videos by 14% compared with traditional methods.

Characterization and Expression Analysis of Regeneration-Associated Protein (Aj-Orpin) during Intestinal Regeneration in the Sea Cucumber Apostichopus japonicus.

Apostichopus japonicus achieves intestinal regeneration in a short period after evisceration, and multiple genes are involved in this process. The transcriptome of A. japonicus was screened for regeneration-associated protein (Aj-Orpin), a gene that is specifically upregulated during intestinal regeneration. The expression and function of Aj-Orpin were identified and investigated in this study. The 5' and 3' RACE polymerase chain reaction (PCR) was used to clone the full-length cDNA of Aj-Orpin. The open reading frame codes for a 164 amino-acid protein with an EF-hand_7 domain and overlapping signal peptides and transmembrane regions. Moreover, Aj-Orpin mRNA and protein expression during intestinal regeneration was investigated using real-time quantitative PCR and Western blot. The expression pattern of Aj-Orpin in the regenerating intestine was investigated using immunohistochemistry. The results showed that Aj-Orpin is an exocrine protein with two EF-hand-like calcium-binding domains. Expression levels were higher in the regenerating intestine than in the normal intestine, but protein expression changes lagged behind mRNA expression changes. Aj-Orpin was found to play a role in the formation of blastema and lumen. It was primarily expressed in the serosal layer and submucosa, suggesting that it might be involved in proliferation. These observations lay the foundation for understanding the role of Orpin-like in echinoderm intestinal regeneration.

The sea cucumber genome provides insights into morphological evolution and visceral regeneration.

Apart from sharing common ancestry with chordates, sea cucumbers exhibit a unique morphology and exceptional regenerative capacity. Here we present the complete genome sequence of an economically important sea cucumber, A. japonicus, generated using Illumina and PacBio platforms, to achieve an assembly of approximately 805 Mb (contig N50 of 190 Kb and scaffold N50 of 486 Kb), with 30,350 protein-coding genes and high continuity. We used this resource to explore key genetic mechanisms behind the unique biological characters of sea cucumbers. Phylogenetic and comparative genomic analyses revealed the presence of marker genes associated with notochord and gill slits, suggesting that these chordate features were present in ancestral echinoderms. The unique shape and weak mineralization of the sea cucumber adult body were also preliminarily explained by the contraction of biomineralization genes. Genome, transcriptome, and proteome analyses of organ regrowth after induced evisceration provided insight into the molecular underpinnings of visceral regeneration, including a specific tandem-duplicated prostatic secretory protein of 94 amino acids (PSP94)-like gene family and a significantly expanded fibrinogen-related protein (FREP) gene family. This high-quality genome resource will provide a useful framework for future research into biological processes and evolution in deuterostomes, including remarkable regenerative abilities that could have medical applications. Moreover, the multiomics data will be of prime value for commercial sea cucumber breeding programs.

Post-transcriptional regulation of ERBB2 by miR26a/b and HuR confers resistance to tamoxifen in estrogen receptor-positive breast cancer cells.

Tamoxifen-resistant (TAMR) estrogen receptor-positive (ER+) breast cancer is characterized by elevated Erb-B2 receptor tyrosine kinase 2 (ERBB2) expression. However, the underlying mechanisms responsible for the increased ERBB2 expression in the TAMR cells remain poorly understood. Herein, we reported that the ERBB2 expression is regulated at the post-transcriptional level by miR26a/b and the RNA-binding protein human antigen R (HuR), both of which associate with the 3'-UTR of the ERBB2 transcripts. We demonstrated that miR26a/b inhibits the translation of ERBB2 mRNA, whereas HuR enhances the stability of the ERBB2 mRNA. In TAMR ER+ breast cancer cells with elevated ERBB2 expression, we observed a decrease in the level of miR26a/b and an increase in the level of HuR. The forced expression of miR26a/b or the depletion of HuR decreased ERBB2 expression in the TAMR cells, resulting in the reversal of tamoxifen resistance. In contrast, the inactivation of miR26a/b or forced expression of HuR decreased tamoxifen responsiveness of the parental ER+ breast cancer cells. We further showed that the increase in HuR expression in the TAMR ER+ breast cancer cells is attributable to an increase in the HuR mRNA isoform with shortened 3'-UTR, which exhibits increased translational activity. This shortening of the HuR mRNA 3'-UTR via alternative polyadenylation (APA) was observed to be dependent on cleavage stimulation factor subunit 2 (CSTF2/CstF-64), which is up-regulated in the TAMR breast cancer cells. Taken together, we have characterized a model in which the interplay between miR26a/b and HuR post-transcriptionally up-regulates ERBB2 expression in TAMR ER+ breast cancer cells.

IL-13 -1112 polymorphism and periodontitis susceptibility: a meta-analysis.

BACKGROUND: Several studies have examined the association between the IL-13 -1112C/T polymorphism and the risk of periodontitis. However, these studies have reached different conclusions. The aim of the current study was to investigate the link between this IL-13 -1112 polymorphism and susceptibility to periodontitis. METHODS: We utilized electronic databases, including the CNKI (China National Knowledge Infrastructure), Wanfang, PubMed, Embase, and Cochrane Library databases, to manually search for relevant research published through November 30, 2016. The Chinese and English terms used to search the literature included "periodontitis", "periodontal disease", "IL 13", "IL-13", and "interleukin-13". In accordance with our inclusion criteria, we selected studies that involved case-control trials. All of these case-control trials described their objectives, design and specific statistical methods. For all included studies, odds ratios (ORs) and 95% confidence intervals (95% CIs) were provided or could be calculated from the study data. The quality of the included literature was evaluated using the Newcastle-Ottawa scale (NOS). STATA 12.0 was used to calculate the sizes of the combined effects and conduct a sensitivity analysis of the results. RESULTS: Our meta-analysis included 4 articles representing 5 case-control studies with a total of 710 cases and 671 control subjects. The meta-analysis results indicated that the CC vs TT model, CT vs TT model and TT vs CT + CC model (CC VS TT: OR = 0.615, 95% CI = 0.395-0.957; CT vs TT: OR = 0.518, 95% CI = 0.323-0.830; and TT vs CT + CC: OR = 1.739, 95% CI = 1.130-2.676) were significant in five IL-13 -1112 gene polymorphism and periodontitis susceptibility models. Subgroup analysis indicated that the CC vs TT, CT vs TT and TT vs CT + CC models were significant in the chronic periodontitis (CP) group, whereas no significant differences were found in the five aggressive periodontitis (AgP) group models. The sensitivity analysis showed that dropping any single study did not affect the pooled analysis results. CONCLUSION: The IL-13 -1112 polymorphism may be associated with susceptibility to periodontitis. The IL-13 -1112 gene polymorphism may be associated with susceptibility to CP but not to AgP. Thus, large-scale, multi-ethnic case-control trials are still warranted.

Autologous menstrual blood-derived stromal cells transplantation for severe Asherman's syndrome.

STUDY QUESTION: Does autologous transplantation of menstrual blood-derived stromal cells (menSCs) regenerate endometrium to support pregnancy in patients with severe Asherman's syndrome (AS)? SUMMARY ANSWER: Autologous menSCs transplantation significantly increases endometrial thickness (ET) for women with severe AS. WHAT IS KNOWN ALREADY: AS is a major cause of secondary infertility in women. Cell transplantation has been tried in a few clinical cases with encouraging results. STUDY DESIGN, SIZE, DURATION: In this experimental, non-controlled and prospective 3-year clinical study involving seven patients with AS, autologous menSCs were isolated and cultured from menstrual blood of each patient within ~2 weeks and then transplanted back into their uterus. Endometrial growth and pregnancy were assessed after cell therapy. PARTICIPANTS/MATERIALS, SETTING, METHOD: Infertile women, aged 20-40 years, diagnosed with severe AS (Grade III-V) by hysteroscopy and with menstrual fluid were recruited at the Shengjing Hospital affiliated to China Medical University. Autologous menSCs transplantation was conducted followed by HRT. Endometrial thickness was monitored with frozen embryo transfer (FET) as needed. MAIN RESULTS AND THE ROLE OF CHANCE: We successfully cultured menSCs from seven patients and transferred the autologous cells back to their uterus. Our results showed that the ET was significantly (P = 0.0002) increased to 7 mm in five women, which ensured embryo implantation. Four patients underwent FET and two of them conceived successfully. One patient had spontaneous pregnancy after second menSCs transplantation. LIMITATIONS, REASONS FOR CAUTION: Limited sample size, lack of rigorous controls or knowledge of underlying mechanism. WIDER IMPLICATIONS OF THE FINDINGS: Autologous menSCs transplantation is a potential option for treating women with severe AS. STUDY FUNDING/COMPETING INTERESTS: This study was supported by Liaoning Provincial Science and Technology Program. The sponsor and authors declare no conflicts of interest. TRIAL REGISTRATION NUMBER: Registered in the Chinese Clinical Trial Registry (ChiCTR-ONB-15007464).

Antihypertensive effects of fargesin in vitro and in vivo via attenuating oxidative stress and promoting nitric oxide release.

Fargesin, a bioactive neolignan isolated from magnolia plants, is widely used in the treatment of managing rhinitis, inflammation, histamine, sinusitis, and headache. To provide more biological information about fargesin, we investigated the effects of fargesin on rat aortic rings and 2-kidney, 1-clip (2K1C) hypertensive rats. In vitro, fargesin caused concentration-dependent vasorelaxation in rat isolated aortic rings induced by KCl and norepinephrine. The effect was weakened by endothelium denudation and nitric oxide (NO) synthesis inhibition. In vivo, the evolution of systolic blood pressure (SBP) was followed by weekly measurements. Angiotensin II (Ang II) and endothelin (ET) levels, NO and nitric oxide synthase (NOS), and plasma and liver oxidative stress markers were determined at the end of the experimental period. After 5 weeks of fargesin treatment, we found that fargesin treatment reduced SBP, cardiac hypertrophy, and Ang II and ET levels of hypertensive rats. Increased NOS activity and NO level were observed in fargesin-treated rats. Normalisation of plasma MDA concentrations and improvement of the antioxidant defence system in plasma and liver accompanied the antihypertensive effect of fargesin. Taken together, these results provided substantial evidences that fargesin has antihypertensive effect in 2K1C hypertensive rats via inhibiting oxidative stress and promoting NO release.

Identification and characterization of a progestin and adipoQ receptor (PAQR) structurally related to Paqr7 in the ovary of Cynoglossus semilaevis and its potential role in regulating oocyte maturation.

Membrane progestin receptors (mPRs) play an important role in the regulation of oocyte meiotic maturation in fish. However, details of the molecular endocrine mechanism regulating oocyte maturation in multiple spawning fish with asynchronous ovarian development remain unclear. The cDNA encoding a novel progestin and adipoQ receptor with structural similarity to mPRα (Paqr7), herein called Paqr7b, was cloned and sequenced from the ovary of half-smooth tongue sole Cynoglossus semilaevis. Phylogenetic analysis showed that Paqr7b represents an evolutionary intermediate between mPRα and mPRß and shares high homology with other similar Paqr proteins in other teleost species. However, the tongue sole Paqr7b protein showed much greater homology to teleost mPRαs (average 52%) than mPRßs (average 40%), suggesting it may have arisen from gene duplication of mPRα. paqr7b and paqr7 mRNA exhibited similar patterns of tissue expression. The mRNA and protein of Paqr7b were ubiquitously detected in all tissues analyzed, including the ovary. Moreover, in situ hybridization results revealed that paqr7b was expressed in stage V oocytes, as well as in scattered cells in the pituitary. The expression of paqr7b mRNA in brain and ovary significantly increased from ovarian development stage II to stage V (P<0.05), and was maximal at stage V, and then sharply decreased at stage VI. The transcript level of paqr7b mRNA in the pituitary also peaked at stage V (P<0.05). Treatment of tongue sole ovarian follicles with gonadotropin consistently increased the expression level of Paqr7b protein and mRNA in both a dose- and stage-dependent manner. Microinjection of tongue sole oocytes with a morpholino antisense oligonucleotide to Paqr7b blocked the progestin induction of oocyte maturation. Our findings demonstrate an important role of Paqr7b in the regulation of oocyte maturation in tongue sole and suggest the receptor may also influence other aspects of reproduction, such as pituitary function.

c-MYC-regulated miR-23a/24-2/27a cluster promotes mammary carcinoma cell invasion and hepatic metastasis by targeting Sprouty2.

Emerging evidence indicates that the miR-23a/24-2/27a cluster may possess a causal role in mammary tumorigenesis and function as a novel class of oncogenes. However, the regulatory mechanism of the miR-23a/24-2/27a cluster in mammary carcinoma cell invasion and migration is still largely unknown. We observed that the expression levels of miR-23a, miR-24-2 and miR-27a were significantly higher in breast cancer with lymph node metastasis, compared with that from patients without lymph node metastasis or normal tissue. Forced expression of the miR-23a/24-2/27a cluster promoted mammary carcinoma cell migration, invasion, and hepatic metastasis, through targeting Sprouty2 (SPRY2) and consequent activation of p44/42 MAPK. Epidermal growth factor induced the expression of the transcription factor c-MYC, which promoted the expression of mature miR-23a, miR-24-2, and miR-27a and subsequently decreased expression of SPRY2 and activated p44/42 MAPK to promote mammary carcinoma cell migration and invasion. We therefore suggest a novel link between epidermal growth factor and the miR-23a/24-2/27a cluster via the regulation of c-MYC, providing the potential for the miR-23a/24-2/27a cluster to be used as biomarker in the diagnosis and/or treatment of breast cancer.

Iodine-mediated thiolation of substituted naphthols/naphthylamines and arylsulfonyl hydrazides via C(sp2)-H bond functionalization.

A direct method has been developed for iodine-mediated thiolation of naphthols/naphthylamines and arylsulfonyl hydrazides through the formation of C-S bond and cleavage of S-N/S-O bonds. In this transformation, a range of valuable thioethers are easily achieved in moderate to good yields.

I2-catalyzed synthesis of substituted pyrroles from α-amino carbonyl compounds and aldehydes.

A direct method for the synthesis of 1,3,4-triarylpyrroles was achieved easily from cyclization of α-amino carbonyl compounds and aldehydes catalyzed by I2. Various substituted groups can be employed, and this reaction can proceed smoothly in moderate to good yields.

I2-mediated oxidative cyclization for synthesis of substituted indolizines.

A direct method for the synthesis of substituted indolizines by means of I2-mediated oxidative tandem cyclization via C-N/C-C bond formation was developed. Various substituted aromatic/aliphatic enolizable aldehydes and 2-pyridylacetates/acetonitrile/acetone proceeded smoothly in this transformation, and the desired products were generated in moderate to good yields.

High-expression ß(1) adrenergic receptor/cell membrane chromatography method based on a target receptor to screen active ingredients from traditional Chinese medicines.

ß-Adrenergic receptors are important targets for drug discovery. We have developed a new ß1 -adrenergic receptor cell membrane chromatography (ß1 AR-CMC) with offline ultra-performance LC (UPLC) and MS method for screening active ingredients from traditional Chinese medicines. In this study, Chinese hamster ovary-S cells with high ß1 AR expression levels were established and used to prepare a cell membrane stationary phase in a ß1 AR-CMC model. The retention fractions were separated and identified by the UPLC-MS system. The screening results found that isoimperatorin from Rhizoma et Radix Notopterygii was the targeted component that could act on ß1 AR in similar manner of metoprolol as a control drug. In addition, the biological effects of active component were also investigated in order to search for a new type of ß1 AR antagonist. It will be a useful method for drug discovery as a leading compound resource.

[Effects of bushen zhuyun decoctlon on the reproductive capacity of mice: an experimental research].

OBJECTIVE: To study the effects of Bushen Zhuyun Decoction (BZD) on the reproductive capacity of mice. METHODS: Totally 60 female Kunming mice were randomly divided into the experimental group and the control group. BZD was perfused by gastric tube to mice in the experimental group, twice daily. Meanwhile, mice in the control group were administered with normal saline by gastrogavage. Mice were sacrificed on the 10th day and the 20th day of medication respectively, 15 mice each time in each group. The serum levels of estradiol and progesterone were detected by radioimmunoassay. The morphological changes of uterus and ovary were observed using HE staining. The expressions of leukaemia inhibitory factor (LIF), epidermal growth factor (EGF), and calcitionin (CT) were determined using immunohistochemical assay. RESULTS: Compared with the control group at the same time point, the weights of uterus and ovary increased, the serum levels of estradiol and progestogen increased, the expressions of LIF, CT, and EGF increased in the experimental group on the 10th day and the 20th day of medication (P <0.05, P <0.01). Better results were shown on the 20th day of medication (P <0.05). Histological results showed increased ovarian follicle numbers, increased endometrial gland numbers, endometrial hyperplasia (stratiform arranged), and increased stromal cells in the experimental group, especially on the 20th day of medication. CONCLUSION: BZD could improve the reproductive capacity by advancing the development of generative organs, promoting the secretion of estradiol and progestogen and the follicular growth, and increasing the receptivity of endometrium.

Firm value in the airline industry: perspectives on the impact of sustainability and Covid-19.

To date, there has been limited research undertaken into firm value determinants in the air transport industry, one of the most essential sectors for global business. In view of this, in this study, we review and synthesise the literature that focuses on the value of firms in this sector and discuss conceptually and empirically the determinants influencing airlines' stock values. Our main objective is to widen our understanding of the current state of research on the firm value of air transport companies. Using the systematic literature review (SLR) approach, we classify 173 papers published from 1984 to 2021. We find considerable changes in academic interest in the topic over the time period analysed, especially as a consequence of crisis-induced market crashes. In addition, we classify the main research themes relating to airlines' market value, identify gaps, and introduce potential future research avenues in this area. Among the themes identified, the adjustment in the industry-level factors such as alliances, market structure and competition were the most common source of fluctuations in airlines' stock value. However, we find shifting to sustainability initiatives and its consequence for stakeholders' value as one of the most discussed topics in this context. The trend has gained attention since early 2020 due to the emergence of the Covid-19 pandemic as companies are looking for green and sustainable ways to protect the value in crisis time. Our findings assist transportation researchers and executives in addressing major value drivers of airline firms.

Effect of γ-irradiation on structure, physicochemical property and bioactivity of soluble dietary fiber in navel orange peel.

Soluble dietary fibers are widely used in functional food. In this work, the effects of γ-irradiation on molecular weight, structure, physicochemical properties and bioactivities of soluble dietary fiber in navel orange peel (OSDF) were investigated. Γ-irradiation enhanced the extraction yield of OSDF. The molar ratio of glucose and galacturonic acid was increased. The molecular weight profile of OSDF was modified. Γ-irradiation (3-6 kGy) improved the water holding capacity, water swelling capacity, oil holding capacity, cation-exchange capacity, nitrite adsorption capacity and total antioxidant capacity of OSDF. Glucose adsorption capacity and bifidobacterium proliferation capacity of OSDF were improved in a dose-dependent behaviour. Moreover, γ-irradiation promoted the cracking of microstructure. FT-IR spectra showed that more carboxyl groups were newly formed by γ-irradiation. These findings indicated that γ-irradiation treatment was an efficient technique for improving physicochemical properties and health benefits.

Screening vasoconstriction inhibitors from traditional Chinese medicines using a vascular smooth muscle/cell membrane chromatography-offline-liquid chromatography-mass spectrometry.

We developed an analytical method for screening vasoconstriction inhibitors from traditional Chinese medicines (TCMs) by combining vascular smooth muscle/cell membrane chromatography (VSM/CMC) with liquid chromatography-tandem mass spectrometry (LC-MS/MS). Primary cultured VSM cells from rat thoracic aortas were used for preparation of the stationary phase of the VSM/CMC column. Retention fractions from the VSM/CMC column were collected and then analyzed by LC-MS/MS under the optimized conditions offline. The suitability and reliability of the VSM/CMC-offline-LC-MS/MS method was assessed using nitrendipine and nifedipine as positive controls, and this method was then applied to screen vasodilator components from the extracts of Fructus Schisandrae Chinensis (FSC) and Fructus Schisandrae Sphenantherae (FSS). The major components from both species retained by VSM/CMC were identified as deoxyschizandrin (DSD) and schisantherin A (STA) by LC-MS/MS. Competition experiments indicated that DSD and nifedipine bound competitively to membrane receptors, while DSD and STA had partly overlapping binding sites on VSM-cell membranes. In vitro pharmacological trials confirmed that STA and DSD could dose-dependently relax the rat thoracic aortas pre-contracted by KCl. Our VSM/CMC-offline-LC-MS/MS method can be applied for screening vasoconstriction inhibitors from TCMs collected from FSC and FSS, and may be useful in the development of vasodilators from natural products.

Determinants of financial distress in the European air transport industry: The moderating effect of being a flag-carrier.

Due to the COVID-induced global collapse in demand for air travel, the year 2020 was a catastrophic one for the aviation industry. A dramatic drop in operating revenues along with continuing fixed expenses drained the cash reserves of airlines, with consequent risks of financial distress and, potentially, even of bankruptcy. Flag-carriers are a special group in the airline business-they are considered to have privileges in terms of the support given by governments while, on the other hand, are often viewed as having low efficiency and performance. This study aims to estimate for European airlines the interaction effect of being a flag-carrier (flagship) with the relationship between leverage, liquidity, profitability, and the degree of financial distress. Findings obtained from analysing 99 European airlines over a period of ten years, indicate that the negative influence of leverage on financial stability is higher in the case of flag carriers (flagship). The impact of liquidity and profitability on financial health is more positive for flagship than for non-flagship carriers. These findings are not limited to contributing to the existing literature, but also have significant practical implications for executives, managers, and policy makers in the European air transport sector.

[Experimental study of repairing rabbit femur defect with NPP/C-HA/ rhBMP-2].

PURPOSE: To investigate the osteogenic effect of nano-grade pearl powder(NPP)/chitosan-hyaluronic acid (C-HA)/recombinant human bone morphology protein-2 (rhBMP-2) artificial bone. METHODS: A bone defect model with a diameter of 7 mm and a height of 10 mm was made at the distal end of the femur. NPP/C-HA stent containing rhBMP-2 was prepared according to the shape of the defect. No material was implanted in the defect as blank group. NPP/C-HA was used as the control group, NPP/C-HA/rhBMP-2 was implanted into the experimental group. At 4 weeks, 8 weeks, and 12 weeks, the bone effects of each component were detected by cone-beam CT(CBCT), H-E and Masson staining. Serum ALP activity and OCN in tissues to determine the osteogenic differentiation and osteogenesis maturity were detected. SPSS 18.0 software package was used for statistical analysis. RESULTS: At 12 weeks, the defect was completely repaired in the experimental group. No immunological side effects such as inflammation and rejection were observed. At 8 and 12 weeks, CBCT showed that the experimental group had a higher CT value (Hounsfield units, HU) compared with the control group and the blank group(P<0.05). H-E and Masson staining showed that the experimental group had obvious new bone formation compared with the control group and the blank group at 8 weeks and 12 weeks, and ALP activity of the experimental group was significantly different from the control group and the blank group at 8 weeks. OCN immunohistochemical scoring of the experimental group was significantly different from the control group and the blank group(P<0.05). CONCLUSIONS: NPP/C-HA/rhBMP-2 has good tissue fusion, osteoinductivity, osteoconductivity and osteogenicity, which is expected to provide more effective treatment for bone repair.