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A previous report suggested that the expression of ten-eleven translocation (TET) proteins is abnormal in certain cancers. Quercetin has been demonstrated as anti-cancer role in cancer development. In order to explore the inhibitory effect and mechanism of quercetin on uveal melanoma cells, the expression of TET proteins was analyzed in the present study. Our results suggest that the expression of TET1 was increased following treatment with quercetin in OCM-1, SK-MEL-1, and B16 cells. In addition, quercetin treatment induced apoptosis and inhibited migration and invasion. To further investigate the association of the expression of TET1 with cell growth, apoptosis, migration, and invasion, cell lines in which TET1 was knocked-down or overexpressed were constructed. The results showed that the increased expression of TET1-induced apoptosis, increased 5-hydroxymethylcytosine (5 hmC). and inhibited invasion. Our bioinformatics studies indicated that TET1 is a target gene of microRNA-17 (miR-17) Our results showed that inhibition of the expression of miR-17 resulted in increased TET1 expression in OCM-1 cells. Furthermore, our results indicated that quercetin treatment increased TET1 expression and inhibited melanoma growth in nude mice. Taken together, our results suggest that quercetin can regulate cell proliferation and apoptosis through TET1 via miR-17 in melanoma cells. [ABSTRACT FROM AUTHOR]

Summary: YWHAZ (14‐3‐3ζ) plays crucial roles in regulating proliferation, apoptosis, migration, and invasion of gastric cancer (GC) cells. However, its extensive roles and potential mechanisms in GC cells remain unknown, and need to be researched deeply. In this study, we focus on the role of miR‐375/YWHAZ axis in migration, invasion and epithelial‐to‐mesenchymal transition (EMT) of GC cells. YWHAZ level was assessed by western blot and qPCR assays in GC cells. Scratch and transwell assays were used to determine the migration and invasion of GC cells. The protein levels of correlative molecules were detected by western blot. The regulation of miR‐375 on the expression of its target gene YWHAZ was verified by dual‐luciferase report system. According to the results, knockdown of YWHAZ inhibited the migration, invasion and EMT of GC cells. Moreover, silencing of YWHAZ restrained the activation of wnt/β‐catenin signalling pathway. YWHAZ was confirmed to be a target gene of miR‐375, and its expression was regulated by miR‐375 in GC cells. Transfection of miR‐375 inhibitor promoted the migration, invasion, EMT and activation of wnt/β‐catenin pathway in GC cells, which was suppressed by inhibition of YWHAZ. Taken together, this study suggests that miR‐375/YWHAZ axis may be served as a novel therapeutic target for GC patients. [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC) is a common malignancy, most of which remain unresponsive to chemotherapy. Methotrexate (MTX) is one of the earliest cytotoxic drugs and serves as an anti-metabolite and anti-folate chemotherapy for various types of cancer. However, MTX resistance prevents its clinical application in cancer therapy. Thereby, overcoming the drug resistance is an alternative strategy to maximize the efficacy of MTX therapies in clinics. Long non-coding RNAs (lncRNAs) have gained widespread attention in recent years. More and more evidences have shown that lncRNAs play regulatory roles in various biological activities and disease progression including drug resistance in cancer cells. Here, we observed lncRNA TUG1 was associated to the MTX resistant in colorectal cancer cells. Firstly, quantitative analysis indicated that TUG1 was significantly increased in tumors which were resistant to MTX treatment. TUG1 knockdown re-sensitized the MTX resistance in colorectal cancer cells, which were MTX-resistant colorectal cell line. Furthermore, bioinformatics analysis showed that miR-186 could directly bind to TUG1, suggesting TUG1 might worked as a ceRNA to sponge miR-186. Extensively, our study also showed that CPEB2 was the direct target of miR-186 in colorectal cancer cells. Taken together, our study suggests that lncRNA TUG1 mediates MTX resistance in colorectal cancer via miR-186/CPEB2 axis. [ABSTRACT FROM AUTHOR]

Object: To compare the clinical efficacy of titanium mesh cages and autogenous iliac bone graft to restore vertebral height through posterior approach in patients with thoracic and lumbar spinal tuberculosis. Method: 59 patients with spinal tuberculosis underwent interbody fusion and internal fixation through posterior approach in our department from January 2011 to December 2013. In group A, 34 patients obtained titanium mesh for the reconstruction of vertebral height, among them 25 patients (group A1) suffered from single-segment spinal tuberculosis, and 9 patients, (group A2) had multi-segment spinal tuberculosis. In group B, 25 patients got autogenous iliac bone graft to restore vertebral height, including 24 patients with single-segment spinal tuberculosis (group B1), and 1 patient with multi-segment spinal tuberculosis (group B2). The clinical efficacy was evaluated based on average operation time, blood loss, hospital stays, hospitalization expenses, visual analog scale (VAS), Oswestry Disability Index (ODI), erythrocyte sedimentation rate (ESR), C-Reactive protein (CRP), neurological function recovery, bony fusion, intervertebral height, Cobb angle and postoperative complications. Results: Final follow-up time was an average of 35.5 months ranging from 15 to 56 months. All patients were completely cured and obtained solid bone fusion. The bony fusion time was 9.4±6.1 months in group A1, 10.2±2.7 months in group A2 and 8.7±3.6 months in group B1. There were no significant difference among three groups (P>0.05). The Cobb correction and restoration of intervertebral height significantly improved compared with those in preoperation, but without significant difference among three groups (P>0.05). The loss of angular correction and intervertebral height in group A1 were found to be less than those in group B1 (P<0.05), but with no significant difference between group A1 and group A2, and between group A2 and group B1 (P>0.05). Patients in group B1 got the most loss of angular correction and intervertebral height. In addition, neurological function was revealed to be significantly improved after surgery. There were significant differences of VAS, ODI, ESR and CRP between preoperation and postoperation at the final follow-up time (P<0.05), with no significant difference among three groups (P>0.05). No statistically significant difference was found when analyzing blood loss, hospital stays, hospitalization expenses, and corrective cost among three groups (P>0.05). Complications included cerebrospinal fluid leakage (2 cases in group A1 and group A2), sinus formation (3 cases in group A1, group A2 and group B1), and intervertebral infection (1 case in group B1), but no implant failure or donor site complications was found in any patient. Conclusions: Titanium mesh cages could obtain good clinical efficacy comparable to autogenous iliac bone graft when treating single-segment spinal tuberculosis, and may be better than autogenous iliac bone graft for treating multi-segment spinal tuberculosis. [ABSTRACT FROM AUTHOR]

Background: Colorectal cancer (CRC) is a common digestive tract malignancy with high incidence and mortality rates. Radiotherapy is the most common anti-tumor therapeutic regime and is frequently used for treating CRC, especially rectal cancer. However, radiotherapy can lead to tumor resistance to treatment. While previous research on radiotherapy resistance in CRC has mostly focused on the tumor itself, recent advances, especially the emergence of immunotherapy, have led to a greater emphasis on the immune microenvironment of the tumor. Summary: This review has summarized the recent literature on the role of the tumor immune microenvironment in CRC resistance to radiotherapy and provided new ideas for future anti-tumor treatment strategies. Key Messages: The proportion of immunosuppressive cells is greater than the numbers of cells associated with immune activation, leading to an overall state of immunosuppression; both the tumor and immunosuppressive cells secrete increased amounts of immunosuppressive regulatory factors, reduce the recognition and presentation of tumor antigens, inhibit immune cell's anti-tumor effect, and offset the non-targeted anti-tumor effect of radiotherapy. [ABSTRACT FROM AUTHOR]

Activating transcription factor 1 (ATF1) may be involved in essential hypertension (EH) by induction of NADPH oxidase 1 (NOX1) and radical oxygen species (ROSs) production. Abnormal expression of ATF1 was found in EH in previous microarray analysis. Here we tested whether a single nucleotide polymorphism (SNP) located in the 3′-untranslated region (3′UTR) of ATF1 was associated with EH susceptibility by affecting microRNA (miRNA) binding. In silico analysis indicated that rs11169571 (T > C) was a candidate SNP to modulate miRNA: ATF1 mRNA complex, with the greatest changed energy for hsa-miR-1283, and the luciferase reporter analysis showed that miR-1283 inhibited the activity of the reporter vector carrying –T allele, but not the –C allele. In addition, inhibition of miR-1283 in HA-VSMCs enhanced the expression of ATF1 mRNA as well as the ROS levels. Further case-control study showed that rs11169571 was significantly associated with increased risk of EH. Finally, we observed an increased ATF1 protein level in peripheral blood of EH patients with CC carriers compared to TT carriers of rs11169571, with an intermediate ATF1 level in TC carriers. These results suggested that rs11169571 of ATF1 gene may be associated with EH, and the SNP-modified posttranscriptional gene regulation by miRNAs could be a potentially pathogenetic mechanism of EH. [ABSTRACT FROM AUTHOR]

A cis-9-octadecenoic acid (OA) surface-modified TiO2 nanoparticle with average diameter of 30 nm was chemically synthesized. The tribological properties of the prepared OA–TiO2 nanoparticle as an additive in water were evaluated with a four-ball tester. The results show that the OA–TiO2 nanoparticle exhibits good antiwear and friction reduction properties as well as load-carrying capacity. The maximum non-seizure load (PB value) can be raised about 6–10 times when 0.1–1.0% OA–TiO2 nanoparticle was added into water. The rubbed surface after friction tests was investigated with X-ray photoelectron spectroscopy (XPS). The results of XPS analysis indicate that a boundary film mainly composed of TiO2 and oleic acid complex, was formed on the rubbed surface. [Copyright &y& Elsevier]

• Immunomodulatory mechanisms of yupingfeng granules were investigated by integration of metabolomics and network pharmacology. • The potential regulatory mechanism was related to bile acid metabolism and inflammation. • Flavonoids and saponins were found to be the major active ingredients in the immunomodulatory effects of yupingfeng granules. • Biological verification was also performed. Systems biology is an approach that employs modern biological techniques and methods to combine the overall regulation of the body by Chinese herbal formulas with systems analysis at the molecular level. In this study, the underlying immunomodulatory mechanisms of yupingfeng granules (YPFG) were investigated based on the integration of metabolomics and network pharmacology methods. Selected routine peripheral blood indicators, body weight, and organ indices related to immunity were firstly measured in order to evaluate the effects of YPFG in cyclophosphamide-induced immunocompromised rats. Plasma metabolomics analyses were carried out by UPLC-Q-TOF-MS combined with a multivariate data analysis. Our study indicates that the potential regulatory mechanism was related to bile acid and glycerophospholipid metabolism, involving the regulation of 11 metabolites, including 8 bile acids, 1 phosphatidylserine, and 2 phosphatidylethanolamines. By means of network pharmacology, the compound-target network between potential active components of YPFG and immune dysregulation was constructed, which releated to estrogen receptor, PPAR, MAPK, PI3K-Akt, JNK signaling pathways, and ubiquitin-mediated protein degradation. The immunomodulatory effect of YPFG may be exerted through regulating lipid metabolism, then bile acid metabolism and inflammation were affected. Biological verification was also performed on cyclophosphamide-induced immunocompromised BALB/c mice. Flavonoid and saponin, two types of compounds in YPFG, were found to be the major active ingredients in the immunomodulatory effects of YPFG, and these components may regulate the abnormal metabolism of bile acids by enhancing the expression of FXR and LXRα. This work elucidated active ingredients, potential biomarkers, and mechanisms of action in the immunoregulatory effects of YPFG from the perspective of systems biology, which provides a scientific basis for its precise clinical medication. [ABSTRACT FROM AUTHOR]

As the development of object detection technology in computer vision, identifying objects is always an active yet challenging task, and even more efficient and accurate requirements are being imposed on state-of-the-art algorithms. However, many algorithms perform object box regression based on RPN(Region Proposal Network) and anchors, which cannot accurately describe the shape information of the object. In this paper, we propose a new object detection method called Field Network (FN) and Region Fitting Algorithm (RFA). It can solve these problems by Center Field. Center field reflects the probability of the pixel approaching the object center. Different from the previous methods, we abandoned anchors and ROI technologies, and propose the concept of Field. Field is the intensity of the object area, reflecting the probability of the object in the area. Based on the distribution of the probability density of the object center in the visual field perception area, we add the Object Field in the output part. And we abstract it into an Elliptic Field with normal distribution and use RFA to fit objects. Additionally, we add two fields to predict the x,y components of the object direction which contain the neural units in the field array. We extract the objects through these Fields. Moreover, our model is relatively simple and have smaller size, which is only 73 M. Our method improves performance considerably over baseline systems on DOTA, MS COCO and PASCAL VOC datasets, with overall performance competitive with recent state-of-the-art systems. [ABSTRACT FROM AUTHOR]

3D pose estimation is always an active but challenging task for object detection in remote sensing images. In this paper, we present a new algorithm for predicting an object's 3D pose in remote sensing images, called Anchor Points Prediction (APP). Compared to previous methods, such as RoI Transform, our object results of the final output can obtain direction information. We predict the object's multiple feature points based on the neural network to obtain the homograph transformation relationship between object coordinates and image coordinates. The resulting 3D pose can accurately describe the three-dimensional position and attitude of the object. At the same time, we redefine the method I o U A P P for calculating the direction and posture of the object. We tested our algorithm on the HRSC2016 dataset and the DOTA dataset with accuracy rates of 0.863 and 0.701, respectively. The experimental results show that the accuracy of the APP algorithm is significantly improved. At the same time, the algorithm can achieve one-stage prediction, which makes the calculation process easier and more efficient. [ABSTRACT FROM AUTHOR]

The tribological properties of imidazoline borate at different concentration and different load in water were evaluated using a four-ball test machine. The tribological test results showed that the imidazoline borates have good load carrying capacity and lubrication property. The rubbed surfaces were investigated using X-ray photoelectron spectroscopy (XPS) and electron probe microanalyzer (EPMA). The results showed that imidazoline borates reacted with the metal surface in tribological process and produced a complex film, which is composed of organic imidazolines and partially decomposed products. [Copyright &y& Elsevier]

Effect of Runx3 gene on the cell proliferation and invasion of rectal cancer was investigated to explore potential new targets for targeted treatment of rectal cancer. The Runx3 overexpression group (OE group), blank plasmid control group, negative control and blank group of the rectal cancer HRC-9698 cell strain were set. The overexpressed Runx3 plasmid was transfected in OE group; the empty plasmid was transfected in blank plasmid control group; only liposome Lipofectamine was added to negative control group; only 1640 medium was used in blank group. RT-qPCR was used for detection of the mRNA expression of Runx3 in different groups; CCK-8 kit for detection of cell proliferation in different groups; Transwell chamber test for detection of cell strain invasion in different groups. The mRNA expression of Runx3 gene in OE group was the highest, significantly higher than that in blank plasmid control group, negative control and blank group (P<0.01). The OD values of overexpressed Runx3 at 96 h after transfection in OE group was significantly lower than each control group (P<0.01). At the same time-point, pairwise comparison in each group found that OE group was significantly lower than blank plasmid control, negative control and blank groups (all P<0.01). In the invasion experiment, the number of invasion cells in OE, blank plasmid control, negative control and blank groups were 38.63±9.33, 107.87±5.66, 110.93±4.33 and 112.86±6.66, respectively. OE group was significantly lower than each control group (P<0.01). Overexpression of Runx3 gene in vitro inhibits the cell proliferation of rectal cancer and blocks the cell invasion and metastasis. This study provides a new idea and a new molecular therapeutic target for molecular targeted therapy of rectal cancer. [ABSTRACT FROM AUTHOR]

MicroRNA (miR)-613 has been reported to function as a tumor suppressor in several types of cancer. However, the biological function and underlying mechanism in gastric cancer (GC) has remained elusive. Therefore, the aim of the present study was to assess the expression and biological role of miR-613 in GC tissues and cell lines. miR-613 expression was found to be downregulated in 38 GC tissue samples compared to that in their adjacent non-cancerous tissues, and low expression of miR-613 was associated with lymph node metastasis and advanced tumor-nodes-metastasis stage. A gain-of-function assay demonstrated that miR-613 overexpression reduced tumor cell proliferation, migration and invasion of SGC-7901 cells, as determined by MTT and Transwell assays. Furthermore, brain-derived neutrophic factor (BDNF) was identified as a direct target of miR-613 in GC cells by a luciferase reporter assay. BDNF expression was upregulated and inversely correlated with miR-613 levels in GC tissues. In addition, knockdown of BDNF expression mimicked the tumor suppressive effect of miR-613 in GC cells. In conclusion, these findings demonstrated that miR-613 functions as a tumor suppressor in GC by targeting BDNF. Thus, miR-613 is a potential therapeutic target for GC. [ABSTRACT FROM AUTHOR]

F-box protein 11 (FBXO11) has both the E3 ubiquitin ligase activity and the methyltrasferase activity, and regulates metastasis, apoptosis and chemosensitivity in human cancer. However, the clinical significance and biological function of FBXO11 in gastric cancer (GC) are rarely known. Here, we demonstrated up-regulated expression of FBXO11 in GC tissues in comparison with that in tumor-adjacent tissues. Clinical analysis based on our specimens and the TCGA database revealed that FBXO11 overexpression was associated with large tumor size, lymph node metastasis and advanced TNM stage. Notably, GC patients with high FBXO11 expression showed a significant shorter overall survival. Cell proliferation and mobility were measured by CCK-8 and Transwell assays. FBXO11 silencing by transfection with two specific shRNAs attenuated proliferation, migration and invasion of MGC-803 cells. In accordance, FBXO11 overexpression promoted these cellular processes in SGC-7901 cells. Mechanistically, FBXO11 obviously facilitated epithelial-mesenchymal transition (EMT) process as suggested by immunoblotting and immunofluorescence data. Moreover, we found that FBXO11 promoted the activation of AKT pathway with increased phosphorylated AKT level in SGC-7901 cells. LY294002 and Wortmannin, phosphotidylinsitol-3-kinase (PI3K) inhibitors, blocked FBXO11 induced EMT, proliferation, migration and invasion of SGC-7901 cells. Phosphatase and tensin homolog (PTEN), which played a crucial role in regulating PI3K/AKT pathway, was negatively modulated by FBXO11 in GC cells. Taken together, our findings contribute to current understanding of the functions of FBXO11 and suggest a mechanism by which FBXO11 plays an oncogenic role in the development of GC possibly by inhibiting PTEN and subsequently promoting PI3K/AKT pathway activation. [ABSTRACT FROM AUTHOR]

Endoplasmic reticulum aminopeptidase 1 (ERAP1) may be involved in blood pressure regulation by inactivation of angiotensin II and generation of bradykinin. Our previous study with cDNA microarray indicated that the expression of ERAP1 is down-regulated in essential hypertension (EH) patients. Since the 3′untranslated region (3′UTR) is known to play an important role in the post-transcriptional regulation by influencing the stability and translation process of mRNA, the present study aims to identify single nucleotide polymorphisms (SNPs) in the 3′UTR of ERAP1 gene in a case–control study among the Northeastern Han Chinese through PCR-sequencing, and analyze the association with EH. Our results further verified the lower expression level of ERAP1 in the peripheral blood cells in patients with EH (917.12 ± 517.57 vs. 1506.59 ± 1214.09 pg/mL, P = 0.011). Four SNPs, 3′UTR-761G>A, 3′UTR-787C>T, 3′UTR-1008A>C and 3′UTR-1055A>G, were identified in the 3′UTR of ERAP1 . 3′UTR-1008A>C and 3′UTR-1055A>G were in almost complete linkage disequilibrium. Association analysis showed that the genotypic and allelic frequencies of 3′UTR-1008A>C and 3′UTR-1055A>G were significantly different between EH and the control groups. Logistic regression and haplotypic analysis indicated that alleles of E20-1037C and E20-1084G as well as haplotype of C-G were the risk factors of EH (P < 0.05). Subgroup analysis performed by age suggested that the frequencies of genotype and allele of 3′UTR-1008A>C and 3′UTR-1055A>G as well as the haplotypes C-G and A-A were significantly different between EH and the control in the younger group (< 50), but not in the older group (≥ 50). Younger population with the 3′UTR-1008CC and/or 3′UTR-1055GG genotypes also tended to have higher blood pressure, especially the diastolic blood pressure. In conclusion, the 3′UTR-1008A>C and 3′UTR-1055A>G polymorphisms of ERAP1 gene were associated with EH, especially in the younger population, and the haplotype C-G could be the independent marker of EH. [ABSTRACT FROM AUTHOR]

Ginkgo biloba extract (GBE) has antitumor and antioxidant properties, which play a role in regulating gene and protein expression. The ten-eleven translocation (TET) proteins have the ability to regulate epigenetic modifications. However, the abnormal expression of TET2 protein has also been demonstrated in cancer development. In the present study, we analyzed the effects of GBE administration on TET2 expression in human colorectal cancer (CRC). The Cancer Genome Atlas database suggested that the expression of TET2 was lost in CRC. To investigate the expression profiles of TET2, GBE was used to treat CRC cells. The results showed that GBE could increase the expression of TET2 and 5-hydroxymethylcytosine (5hmC). In addition, GBE inhibited cell growth and invasion in SW480 cells. Moreover, to confirm whether TET2 expression affected cell proliferation, apoptosis, migration, and invasion, TET2 was knocked down and a TET2-overexpressing vector was constructed in human CRC cells. The results showed that overexpression of TET2 induced cell proliferation and invasion. Bioinformatic analyses showed that TET2 is a target gene of microRNA-29a (miR-29a). Moreover, reduced expression of miR-29a and increased TET2 expression in CRC cells. GBE was also used to treat a tumor model in nude mice. Compared to the control group, tumor growth was inhibited, and there was increased expression of TET2 in the GBE-treatment group in vivo. In conclusion, these results indicated that GBE inhibited cell proliferation and invasion through TET2 protein expression regulated by miR-29a in the development of CRC. [ABSTRACT FROM AUTHOR]

Introduction: The expression of MiR-135b-5p was up-regulated while Krüppel-like factor 4 (KLF4) expression was extremely low in human gastric carcinoma (GC) tissues. This study aimed to explore the role of miR-135b-5p in GC cells and its influence on various cell capacity and viability by targeting KLF4.Material and Methods: The dual-luciferase reporter assay was first performed and the target relationship between miR-135b-5p and KLF4 was confirmed. Then three GC cell lines and the human normal gastric epithelial cell line (GES1) were analyzed for the expression level of miR-135b-5p and KLF4 mRNA by RT-qPCR. The BGC-823 GC cell line was chosen for subsequent assays.Results: The expression of miR-135b-5p and KLF4 was manipulated via transfection. The changes of proliferation, invasion, migration, viability, cycle and apoptosis of GC cells were evaluated by MTS, colony formation assay, transwell assay, wound healing assay and flow cytometry assay, respectively. Overexpression of MiR-135b-5p enhanced viability, proliferation, invasion and migration of GC cells, increased cell viability and reduced cell apoptosis. Replenishing of KLF4 functioned oppositely.Conclusions: The inhibitory effects of ectopic KLF4 could be attenuated by co-transfection of miR-135b-5p. Collective data suggested that miR-135b-5p has a tumor-promoting role in GC cells via downregulating KLF4. Hence, inhibition of miR-135b-5p could be valuable for treatment of gastric cancer. [ABSTRACT FROM AUTHOR]

Purpose: To compare the efficacy, safety, and technical characteristics of anterior-only and posterior-only approach surgeries for the treatment of consecutive multisegment thoracic and lumbar tuberculosis. Methods: Thirty-five patients who developed consecutive multisegment thoracic and lumbar tuberculosis from September 2012 to May 2016 were retrospectively analyzed. Group A was the posterior-only surgery group, and group B was the anterior-only surgery group. The data on the surgery, deformity correction, functional scores, and complications were compared between the two groups. Results: There was no significant difference in the operation time or blood loss between groups A and B (P > 0.05). The preoperative average Cobb angle of kyphosis in groups A and B were 36.2 ± 15.2° and 27.9 ± 7.7°, respectively, which significantly decreased to 4.9 ± 11.8° and 10.4 ± 5.6° after the operation, respectively (P < 0.05). At the final follow-up, the angles were 7.1 ± 10.5° and 14.6 ± 8.0°. The correction angle and correction rate in group A (31.3 ± 16.6°, 88.6 ± 43.6%) were greater than those in group B (17.5 ± 4.4°, 64.9 ± 14.0%) (P < 0.05). There was no significant difference in the loss angle between groups A and B (P > 0.05), but the loss rate in group B (24.0 ± 27.8%) was higher than that in group A (9.6 ± 10.2%) (P < 0.05). There was no significant difference in the incidence of complications between the two groups (P > 0.05). Conclusion: The posterior-only and anterior-only approaches can lead to satisfactory clinical results in the treatment of patients with consecutive multisegment thoracic and lumbar tuberculosis. With posterior-only surgery, kyphosis can be better corrected, and the correction can be better maintained than with anterior-only surgery. [ABSTRACT FROM AUTHOR]