Identification of PDCL2 as a candidate marker in Sertoli cell-only syndrome by chromatin immunoprecipitation-sequencing and bioinformatics analysis.

Background: Sertoli cell-only syndrome (SCOS) or germ cell aplasia is one of the most serious histopathological subtypes within the scope of non-obstructive azoospermia (NOA). Understanding the molecular mechanism of SCOS and identifying new non-invasive markers for clinical application is crucial to guide proper sperm procurement and avoid unnecessary interventions. This study sought to identify the differentially expressed genes (DEGs) of SCOS by using gene sequencing identity and verify the key marker genes to provide basic data for subsequent research on SCOS. Methods: A total of 50 testicular samples were collected in this study from 25 patients with SCOS and 25 patients with normal spermatogenesis. In total, 5 pairs of testis samples were used for the RNA-sequencing (RNA-seq). We identified the DEGs between the SCOS and normal spermatogenesis patients and conducted a Gene Ontology (GO) analysis and a Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. The expression of the main target gene phosducin-like 2 (PDCL2) was examined by quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry (IHC). Results: In total, 3,133 upregulated DEGs and 1,406 downregulated DEGs were identified by the RNA-seq. The highly enriched processes involved in spermatogenesis included the mitotic cell cycle, cell cycle, and oocyte maturation. The expression of PDCL2 was verified as a downregulation marker in SCOS by qRT-PCR and IHC. Conclusions: This study identified the DEGs of SCOS, and the bioinformatics analysis results identified the potential target key genes and pathways for SCOS. PDCL2 is a key gene involved in SCOS and may serve as a non-invasive downregulation marker of SCOS.

Nitrogen-Doped Carbon Dot as a Lubricant Additive in Polar and Non-polar Oils for Superior Tribological Properties via Condensation Reaction.

Nitrogen-doped lubricating additives have been proved to be an effective strategy to improve the tribological properties of lubricating oil. However, the traditional preparation methods of nitrogen-doped lubricating additives have the defects including harsh preparation conditions and a time-consuming preparation process. Herein, we report a preparation method of nitrogen-doped carbon dot (NCD) lubricating additives in a short time by one-step aldehyde condensation reaction at room temperature. The small size effect and nitrogen-containing functional groups of NCD lubricating additives provide favorable conditions for their dispersion and low friction in base oil. The tribological properties of NCD lubricating additives in sunflower oil (SFO) and PAO10 were systematically evaluated. The results show that NCD lubricating additives could reduce the average friction coefficient of SFO from 0.15 to 0.06 and PAO10 oil from 0.12 to 0.06, and the wear width is also decreased by 50-60%. In particular, the friction curve is very stable, and the friction coefficient was maintained at about 0.06 even under the working time of 5 h. By analyzing the morphology and chemical properties of the worn surface, the lubrication effect of NCDs is attributed to its small size effect and adsorption, which was easy to enter the friction gap to fill and repair. Furthermore, the doping of nitrogen induces the occurrence of friction chemical reactions, forming a friction film of nitrides and metal oxides at the friction interface, which effectively reduces the friction and wear of the surface. These findings provide a possibility for the convenient and effective preparation of NCD lubricating additives.

Pigment production by a newly isolated strain Pycnoporus sanguineus SYBC-L7 in solid-state fermentation.

Natural pigments are playing important roles in our daily lives. They not only make products colorful but also provide various health benefits for humans. In addition, Pycnoporus genus, listed as food- and cosmetic-grade microorganism, is one of the promising organisms for developing natural pigments. In this study, a new fungal strain with high efficiency in producing intense orange pigments was isolated and identified as Pycnoporus sanguineus SYBC-L7. Different agro-industrial wastes were applied to evaluate the growth and pigment production of strain SYBC-L7. SYBC-L7 can grow rapidly and effectively produce pigments using wood chips as substrate in solid-state fermentation (SSF). Culture conditions were also optimized for value-added pigments production and the optimum production conditions were glucose as carbon source, ammonium tartrate as nitrogen source, initial pH 6.0, and relative humidity of 65%. Pigment components, cinnabarinic acid, tramesanguin, and 2-amino-9-formylphenoxazone-1-carbonic acid were confirmed by liquid chromatography-mass spectrometry. Meanwhile, an agar plate diffusion assay was performed to evaluate the antimicrobial activity of the pigment. These pigments showed more significant inhibition of Gram-positive than Gram-negative bacteria. The results showed that Pycnoporus sanguineus SYBC-L7 was able to cost-effectively produce intense natural orange pigments with antibacterial activity in SSF, which is the basis of their large-scale production and application.

Ecological drivers of avian diversity in a subtropical landscape: Effects of habitat diversity, primary productivity and anthropogenic disturbance.

Understanding the roles of ecological drivers in shaping biodiversity is fundamental for conservation practice. In this study, we explored the effects of elevation, conservation status, primary productivity, habitat diversity and anthropogenic disturbance (represented by human population density and birding history) on taxonomic, phylogenetic and functional avian diversity in a subtropical landscape in southeastern China. We conducted bird surveys using 1-km transects across a total of 30 sites, of which 10 sites were located within a natural reserve. Metrics of functional diversity were calculated based on six functional traits (body mass, clutch size, dispersal ratio, sociality, diet and foraging stratum). We built simultaneous autoregression models to assess the association between the ecological factors and diversity of the local avian communities. Local avian diversity generally increased with increasing habitat diversity, human population density and primary productivity. We also detected phylogenetic and functional clustering in these communities, suggesting that the avian assemblages were structured mainly by environmental filtering, rather than interspecific competition. Compared with sites outside the natural reserve, sites within the natural reserve had relatively lower avian diversity but a higher level of phylogenetic heterogeneity.

Synthetic Kilogram Carbon Dots for Superior Friction Reduction and Antiwear Additives.

Because of the high synthesis cost, strong chemical inertness, complex process, and easy to endanger environment of traditional carbon-based nanolubricant additives, the development of its application in lubrication is limited. Therefore, a new type of lubricant additive with low cost, high yield, high performance, and environmental protection is urgently needed. Herein, a kilogram-scale carbon dots (CDs) lubricant additive was prepared by a simple and green one-step reaction of aldol condensation, which showed excellent lubricating properties in water and sunflower oil. The tribological properties of the CDs lubricant additive at different concentrations, loads, and speeds were systematically studied. The results show that the average friction coefficient of water is significantly reduced by 75% by a CDs lubricant additive. In particular, CDs not only exhibited excellent service life and lubrication stability during friction but also kept the friction coefficient change rate of sunflower seed oil close to 0 within 500 min. According to the tribological evaluation and wear surface analysis, the lubrication mechanism of CDs was attributed to their own morphological characteristics and abundant oxygen-containing functional groups on the surface. In the friction process, the charge adsorption effect, the adsorption protective film, and the hydrogen bonding layer are generated, which play an essential role in obvious antiwear and friction reduction. Therefore, this work provides a reference for the preparation of high-performance and high-yield lubricant additives.

New algorithm for corneal densitometry assessment based on anterior segment optical coherence tomography.

PURPOSE: To describe a new algorithm to measure corneal densitometry based on images obtained by swept source anterior segment ocular coherence tomography (SS-AS-OCT) and establish standard densitometry values in a group of normal eyes. METHODS: A total of 111 healthy participants (195 eyes) were enrolled in this study. Using a MATLAB designed algorithm, the cornea was segmented into three layers: anterior, posterior and mid-stroma, and it was divided into two concentric areas, 0-2 and 2-4 mm, resulting in nine areas for the analysis. The mean corneal densitometry values were calculated and expressed as grayscale units (GSU). RESULTS: The mean age was 57 years (range 22-87), with 100 (51.3%) right eyes and 95 (48.7%) left eyes. The total corneal densitometry was 86.9 ± 12.1 GSU. The mid-stroma layer had the highest densitometry values, 87.4 ± 12.1 GSU, and the anterior layer had the lowest values, 81.9 ± 14.2 GSU. Densitometry differences between the anterior layer and the mid-stroma layer (P < 0.001), as well as the anterior layer and the posterior layer (P < 0.05) were statistically significant. The 0-2 mm concentric area had higher mean densitometry values, 97.8 ± 12.7 GSU, and the differences were significant compared to the 2-4 mm concentric area (P < 0.001). No correlation was found between the corneal densitometry values and gender or age. CONCLUSIONS: The new MATLAB segmentation algorithm for the analysis of corneal SS-AS-OCT images is capable to objectively assess corneal densitometry. We provide standard and normal data for better clinical and research approach.

Inhibitory effect of triterpenoids from the mushroom Inonotus obliquus against α-glucosidase and their interaction: Inhibition kinetics and molecular stimulations.

Bioassay-guided fractionation led to the isolation of a series of triterpenoids (1-46) including 12 new ones (1-12) from the mushroom Inonotus obliquus. The structures of all the compounds were elucidated by spectroscopic analysis as well as by comparison with literature data. Triterpenoids 1-3, 6, 7, 16, 24, 25, 27, 38, 43, 44 and 46 showed strong α-glucosidase inhibition, with IC50 values from 11.5 to 81.8 µM. Their structure-activity relationships were discussed. Inonotusol F (24) showed the strongest inhibitory activity and it presented noncompetitive inhibition against α-glucosidase. Molecular docking and molecular dynamics stimulation further demonstrated that GLU302 and PHE298 were key amino acids for the inhibition of inonotusol F (24) towards α-glucosidase. This study indicates the vital role of triterpenoids in explaining hypoglycemic effect of Inonotus obliquus and provides important evidence for further development and utilization of this mushroom.

Induction chemotherapy for the individualised treatment of hypopharyngeal carcinoma with cervical oesophageal invasion: a retrospective cohort study.

BACKGROUND: This study aimed to evaluate the potential of induction chemotherapy as an indicator of the management of advanced hypopharyngeal carcinoma with cervical oesophageal invasion. METHODS: Sixty-eight patients admitted to our hospital between February 2003 and November 2016 with stage IVB hypopharyngeal carcinoma with cervical oesophageal invasion were retrospectively analysed. Patients were divided into two groups according to the treatment they selected following an explanation of the different treatments available. Patients in group A received induction chemotherapy and had (1) complete/partial remission following chemotherapy and radiotherapy/concurrent chemoradiotherapy or (2) stable disease following chemotherapy and surgery. Patients in group B underwent surgery followed by adjuvant radiotherapy/concurrent chemoradiotherapy. Survival analyses were performed using the Kaplan-Meier method, and differences between the groups were evaluated using the log-rank test. Laryngeal and oesophageal retention rates were compared using the cross-tabulation test. RESULTS: The 3- and 5-year overall survival rates were 22.86% and 11.43% in group A and 24.25% and 6.06% in group B, respectively (all P > 0.05). The laryngeal and oesophageal retention rates were 40.0% and 74.3% in group A and 0.0% and 27.3% in group B, respectively (all P < 0.01). There was no statistically significant difference in the incidence of post-operative complications between the two groups (group A 8.6%, group B 12.1%; P > 0.05). CONCLUSIONS: Induction chemotherapy may be an appropriate first choice to ensure laryngeal and oesophageal preservation in the individualised treatment of advanced hypopharyngeal carcinoma with cervical oesophageal invasion.

Dissection of the general two-step di-C-glycosylation pathway for the biosynthesis of (iso)schaftosides in higher plants.

Schaftoside and isoschaftoside are bioactive natural products widely distributed in higher plants including cereal crops and medicinal herbs. Their biosynthesis may be related with plant defense. However, little is known on the glycosylation biosynthetic pathway of these flavonoid di-C-glycosides with different sugar residues. Herein, we report that the biosynthesis of (iso)schaftosides is sequentially catalyzed by two C-glycosyltransferases (CGTs), i.e., CGTa for C-glucosylation of the 2-hydroxyflavanone aglycone and CGTb for C-arabinosylation of the mono-C-glucoside. The two enzymes of the same plant exhibit high homology but remarkably different sugar acceptor and donor selectivities. A total of 14 CGTa and CGTb enzymes were cloned and characterized from seven dicot and monocot plants, including Scutellaria baicalensis, Glycyrrhiza uralensis, Oryza sativa ssp. japonica, and Zea mays, and the in vivo functions for three enzymes were verified by RNA interference and overexpression. Through transcriptome analysis, we found homologous genes in 119 other plants, indicating this pathway is general for the biosynthesis of (iso)schaftosides. Furthermore, we resolved the crystal structures of five CGTs and realized the functional switch of SbCGTb to SbCGTa by structural analysis and mutagenesis of key amino acids. The CGT enzymes discovered in this paper allow efficient synthesis of (iso)schaftosides, and the general glycosylation pathway presents a platform to study the chemical defense mechanisms of higher plants.

MUC1 confers radioresistance in head and neck squamous cell carcinoma (HNSCC) cells.

Mucin 1 (MUC1), a transmembrane glycoprotein, has shown to be as the possible prognostic marker to predict the risk of aggressive head and neck squamous cell carcinoma (HNSCC). In the present study, we investigated the effect of MUC1 in HNSCC cells and the response to X-ray irradiation (IR). Here, we examined the impact of MUC1 overexpression or downexpression on clonogenic survival and apoptosis in response to X-ray irradiation (IR). Radioresistance and radiosensitivity were also observed in HNSCC cells that are MUC1 overexpression and MUC1 downexpression. This enhanced resistance to IR in MUC1-overexpressing cells is primarily due to increased the number of radiation-induced γH2AX/53BP1-positive foci and DNA double-strand break (DSB) repair kinetics. MUC1 overexpression repaired more than 90% of DSBs after 2 Gy radiation by 24 h compared to the empty vector overexpressing cells with less than 50% of DSB repair. However, MUC1 downexpression repaired less than 20% of DSBs compared to the empty vector-overexpresing cells. MUC1 overexpression inhibited proapoptotic protein expression, such as caspase-3, caspase-8, and caspase-9, and induced antiapoptotic protein Bcl-2, followed by resistance to IR-induced apoptosis. Our results showed that targeting MUC1 may be as a promising strategy to counteract radiation resistance of HNSCC cells.

An Identity Authentication Method of a MIoT Device Based on Radio Frequency (RF) Fingerprint Technology.

With the continuous development of science and engineering technology, our society has entered the era of the mobile Internet of Things (MIoT). MIoT refers to the combination of advanced manufacturing technologies with the Internet of Things (IoT) to create a flexible digital manufacturing ecosystem. The wireless communication technology in the Internet of Things is a bridge between mobile devices. Therefore, the introduction of machine learning (ML) algorithms into MIoT wireless communication has become a research direction of concern. However, the traditional key-based wireless communication method demonstrates security problems and cannot meet the security requirements of the MIoT. Based on the research on the communication of the physical layer and the support vector data description (SVDD) algorithm, this paper establishes a radio frequency fingerprint (RFF or RF fingerprint) authentication model for a communication device. The communication device in the MIoT is accurately and efficiently identified by extracting the radio frequency fingerprint of the communication signal. In the simulation experiment, this paper introduces the neighborhood component analysis (NCA) method and the SVDD method to establish a communication device authentication model. At a signal-to-noise ratio (SNR) of 15 dB, the authentic devices authentication success rate (ASR) and the rogue devices detection success rate (RSR) are both 90%.

Modulation of SBD-1 expression by Saccharomyces cerevisiae cell wall components in ovine ruminal epithelial cells.

The ovine rumen is an immune interface with the external environment, participating in host defence responses. Ovine ruminal epithelial cells (ORECs) not only have a physical barrier function, but also secrete sheep ß-defensin-1 (SBD-1), which plays a key role in innate and adaptive immunity. Prebiotics are potential alternatives to infeed antibiotics. Saccharomyces cerevisiae cell wall (S.c.CW) is rich in prebiotics, which play roles in improving the growth performance of animals and regulating immunity. Here, we investigated whether S.c.CW induces SBD-1 expression in ORECs, as well as the underlying mechanism. The regulatory mechanisms of S.c.CW-induced up-regulation of SBD-1 were determined using quantitative real-time PCR, enzyme-linked immunosorbent assay, and western blotting. S.c.CW significantly increased the expression of Toll-like receptor 2 (TLR2) and nuclear factor-kappa B (NF-κB), but had no effect on TLR4 expression. TLR2, MyD88, and NF-κB inhibition attenuated the induction of SBD-1 expression by S.c.CW. However, TLR4 inhibition only resulted in attenuated SBD-1 mRNA, having no effect on SBD-1 protein expression. Thus, we conclude that S.c.CW can induce SBD-1 expression and that this induction is regulated by the TLR2-MyD88-NF-κB pathway.

Comprehensive analysis of the differential expression profile of microRNAs in missed abortion.

To screen the key circulating microRNAs (miRNAs) involved in missed abortion (MA) and explore their role in MA process. We examined the miRNA profile from the serum of three MA patients and three early pregnancy induced abortion patients (controls) by next-generation sequencing. We analyzed the target genes of the differentially expressed (DE) miRNAs to analyze the function and pathway enrichment using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes, respectively. We validated five candidate miRNAs by real time-qPCR. Integrated miRNA-mRNA-pathway network analysis was performed to show the interaction network of the candidate miRNAs and their target genes of interest with the involved pathways. It was observed that 227 miRNAs were differently expressed between the MA group and the early pregnancy control group, with 58 miRNAs downregulated and 169 miRNAs upregulated in the MA group. Real-time qPCR results revealed that expression of the five candidate miRNAs, namely hsa-miR-22-3p, hsa-miR-145-3p, hsa-miR-107, hsa-miR-361-3p, and hsa-miR-378c, was consistent with the miRNA data obtained by sequencing. Integrated miRNA-mRNA-pathway network analysis illustrated that target genes of the candidate miRNAs were mainly involved in the PI3K-Akt signaling pathway, HIF-1 signaling pathway, and VEGF signaling pathway, which would have potential significance in pregnancy and MA. We are the first to reveal the DE miRNAs involved in MA and illustrate their functional interaction network. These results might provide potential circulating biomarkers and new therapeutic targets for MA.

Inhibitory Effect of Five Ganoderma Species (Agaricomycetes) against Key Digestive Enzymes Related to Type 2 Diabetes Mellitus.

Ganoderma mushrooms are widely used in clinical therapies and functional foods. The antidiabetic effect of Ganoderma has become a research hot spot in recent decades. To search for a superior antidiabetic Ganoderma extract, five common Ganoderma species (G. lucidum, G. sinense, G. tsugae, G. applanatum, and G. leucocontextum) were investigated. A total of 10 fractions, including a total triterpenes fraction and a crude polysaccharides fraction for each, were prepared for further assays. Activities of α-glucosidase and α-amylase are inhibited dominantly by triterpenes from all five Ganoderma species rather than the polysaccharides. G. lucidum triterpenes inhibits α-glucosidase and α-amylase most significantly with IC50 values of 10.02 ± 0.95 µg/mL and 31.82 ± 4.30 µg/mL. Even more, triterpenes content was positively correlated with anti-α-glucosidase and anti-α-amylase activities. Therefore, triterpenes were considered to be the active compounds in inhibiting α-glucosidase and α-amylase activity. It is hoped that the results will provide more systematic information for the application of Ganoderma in the functional food and traditional medicine industries in the future.

Correction: Homology analysis of malware based on ensemble learning and multifeatures.

[This corrects the article DOI: 10.1371/journal.pone.0211373.].

Homology analysis of malware based on ensemble learning and multifeatures.

With the exponential increase in malware, homology analysis has become a hot research topic in the malware detection field. This paper proposes MHAS, a malware homology analysis system based on ensemble learning and multifeatures. MHAS generates grayscale images from malware binary files and then uses the opcode tool IDA Pro to extract opcode sequences and system call graphs. Thus, RGB images and M-images are generated on the image matrix. Then, MHAS uses convolutional neural networks (CNNs) as base learners to perform bagging ensemble learning to learn features from the grayscale images, RGB images and M-images. Next, MHAS integrates the nine base learners using voting, learning and selective ensemble (in that order) and maps the integration results to the result matrix. Finally, the result matrix is again integrated using the learning method to obtain the final malware classification result. To verify the accuracy of MHAS, we performed a malware family classification experiment, that included samples of 10 malware families. The results showed that MHAS can reach an accuracy rate of 99.17%, meaning that it can effectively analyze and identify malware families.

The association of pre-pregnancy body mass and weight gain during pregnancy with macrosomia: a cohort study / 中华预防医学杂志

Objective@#To examine the association of pre-pregnancy body mass and weight gain during pregnancy with macrosomia. @*Methods@#From January 2015 to December 2015, a total of 20 477 pregnant women were recruited by probabilistic proportional scale sampling with simple randomization in Sichuan, Yunnan and Guizhou Provinces. Basic information of pregnant women, weight gain during pregnancy and weight of newborn were collected. A multiple logistic regression model was used to assess the association between the pre-pregnancy body mass and gestational weight gain indicators with macrosomia. @*Results@#20 321 mother-infant were included in the final analysis. 20 321 pregnant women were (30.09±4.10) years old and delivered at (39.20±1.29) weeks, among which 12 341 (60.73%) cases were cesarean delivery. The birth weight of 20 321 infants were (3 292.26±431.67) grams, and 970 (4.77%) were macrosomia. The multiple logistic regression model showed that after adjusting for the age of women, compared to the normal weight group in the pre-pregnancy, the overweight and obesity group elevated the risk of macrosomia, with OR (95%CI) about 1.99 (95%CI: 1.69−2.35) and 4.05 (95%CI: 3.05−5.39), respectively. After adjusting for the age, the pre-pregnancy BMI, delivery weeks, delivery mode and infant′s gender, compared to the weight-gain appropriate group, higher weight gain rate in the mid-pregnancy and excessive total gestational weight gain elevated the risk of macrosomia, with OR (95%CI) about 1.99 (95%CI: 1.66−2.39) and 1.80 (95%CI: 1.55−2.08), respectively. @*Conclusion@#The overweight before pregnancy, obesity before pregnancy, the rate of weight gain in the second trimester and the high total weight gain during pregnancy could increase the risk of macrosomia.

Modulation of ovine SBD-1 expression by Saccharomyces cerevisiae in ovine ruminal epithelial cells.

BACKGROUND: The ovine rumen is involved in host defense responses and acts as the immune interface with the environment. The ruminal mucosal epithelium plays an important role in innate immunity and secretes antimicrobial innate immune molecules that have bactericidal activity against a variety of pathogens. Defensins are cationic peptides that are produced by the mucosal epithelia and have broad-spectrum antimicrobial activity. Sheep ß-defensin-1 (SBD-1) is one of the most important antibacterial peptides in the rumen. The expression of SBD-1 is regulated by the probiotic, Saccharomyces cerevisiae (S.c); however, the regulatory mechanism has not yet been elucidated. In the current study, the effects of S.c on the expression and secretion of SBD-1 in ovine ruminal epithelial cells were investigated using quantitative real-time PCR (qPCR) and enzyme-linked immunosorbent assay (ELISA). In addition, specific inhibitors were used to block the nuclear factor kappa-light-chain enhancer of activated B cells (NF-κB), p38, JNK, and ERK1/2 signalling pathways separately or simultaneously, to determine the regulatory mechanism(s) governing S.c-induced SBD-1 upregulation. RESULTS: Incubation with S.c induced release of SBD-1 by ovine ruminal epithelial cells, with SBD-1 expression peaking after 12 h of incubation. The highest SBD-1 expression levels were achieved after treatment with 5.2 × 107 CFU∙mL- 1 S.c. Treatment with S.c resulted in significantly increased NF-κB, p38, JNK, ERK1/2, TLR2, and MyD88 mRNA expression. Whereas inhibition of mitogen-activated protein kinases (MAPKs) and NF-κB gene expression led to a decrease in SBD-1 expression. CONCLUSIONS: S.c was induced SBD-1 expression and the S.c-induced up-regulation of SBD-1 expression may be related to TLR2 and MyD88 in ovine ruminal epithelial cells. This is likely simultaneously regulated by the MAPKs and NF-κB pathways with the p38 axis of the MAPKs pathway acting as the primary regulator. Thus, the pathways regulating S.c-induced SBD-1 expression may be related to TLR2-MyD88-NF-κB/MAPKs, with the TLR2-MyD88-p38 component of the TLR2-MyD88-MAPKs signalling acting as the main pathway.

Endoscopic surgery of a sinonasal inverted papilloma: Surgical strategy, follow-up, and recurrence rate.

BACKGROUND: Sinonasal inverted papilloma (SNIP) is noted for its high rate of recurrence and malignant transformation. Although many clinical studies have demonstrated the effectiveness of the endoscopic approach for SNIP, the surgical strategy has been the subject of much debate. OBJECTIVE: To evaluate the effectiveness of the endoscopic endonasal approach in SNIP. METHODS: A systematic review of patients with a diagnosis of SNIP and who had surgery at our institution from June 2005 to March 2013 was performed. All the patients who had postoperative follow-up for >2 years were enrolled. Each case was categorized into one of four stages as reported by Krouse. Demographic and tumor date, operative approach, complications, and recurrence rates were collected. RESULTS: A total of 125 patients were included in this study. There were 17 patients in stage 1, 40 in stage 2, 57 in stage 3, and 11 in stage 4. The overall recurrence rate was 8.0%. There was no significant difference in recurrence among the stages (all p > 0.05). Recurrence after endoscopic endonasal approach (8.4%) and a combined endoscopic and open exposure procedure (5.6%) were not significantly different (p > 0.05). The recurrence rate was significantly (p < 0.05) higher in patients with revision (15.6%) than in patients in the primary cases (3.8%). A common site of tumor origin was recorded to be from the maxillary sinus (40.2%). Twenty percent of recurrences were observed up to 5 years after surgery. CONCLUSION: Endoscopic surgery may be preferred for treating SNIP. The elevated recurrence rate after revision emphasized the significance of the first surgery. We encourage a follow-up period of at least 5 years.