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Environmental problems caused by micro-pressure waves (MPWs) are increasingly prominent with increase in train speed. Considering different models of trains, which may have differences in nose lengths (Ln), and certain extreme terrains where it is unsuitable to construct the buffer hood outside the tunnel, this study numerically investigated the adaptive relationship between Ln and variable-section tunnel parameters [i.e., the length (L1) and area (S1) of the entrance expansion section] for minimizing the MPW. The results show that, as Ln rises from 5 to 13 m, the formation of the MPW peak is continuously delayed, and the peak value of the MPW decreases; while the optimal L1 remains at 20 m for different Ln. Additionally, the optimal S1 scarcely changes with the increase in Ln as well, between 151 and 156 m2, and its ratio to the section area of the main tunnel (70 m2) is approximately 2.2. The optimal parameters of the entrance expansion section play a universal role for trains with different Ln, which can alleviate the MPW amplitude with a value of 58% or higher. The findings can provide significant support for designing tunnels and tunnel hoods, focusing on alleviating acoustic noise. [ABSTRACT FROM AUTHOR]

Short-chain dehydrogenase/reductases (SDRs) belong to the NAD(P)(H)-dependent oxidoreductase superfamily, which have various functions of catalyzing oxidation/reduction reactions and have been generally used as powerful biocatalysts in the production of pharmaceuticals. In this study, ScSDR1 and ScSDR2, two new SDRs have been identified and characterized from Stachybotrys chartarum 3.5365. Substrate scope investigation revealed that both of the enzymes possessed the ability to oxidize β-OH to ketone specifically, and exhibited substrate promiscuity and high stereo-selectivity for efficiently catalyzing the structurally different prochiral ketones to chiral alcohols. These findings not only suggest that ScSDR1 and ScSDR2 might be potent synthetic tools in drug research and development, but also provide good examples for further engineered enzymes with higher efficiency and stereo-selectivity. [ABSTRACT FROM AUTHOR]

The purpose of the experiment was to investigate the effect of GSE on the production performance, egg quality and serum biochemical indexes of laying hens in the late peak egg laying period. A total of five hundred and forty 53-week-old Jingfen No. 2 laying hens with similar weight, egg production rate and good health were randomly divided into three groups, with six replicates in each group and 30 laying hens in each replicate. The laying hens in group A were fed a basal diet, and GSE was added 200 and 300 mg/kg to the basal diet of group B and group C, respectively. The pre-test period was seven days and the positive trial period was 42 days. The results showed that compared with group A, the average egg weight of the group C was significantly increased (P<0.05), the egg qualification rate of the group B was significantly increased (P<0.05), the eggshell strength of the group B and group C was significantly increased (P<0.05), the protein height of the group C was significantly increased (P<0.05), the serum total protein content of the laying hens in the group B increased significantly (P<0.05), the serum high density lipoprotein content of the laying hens in the group C (P<0.05), and the serum IgA content of laying hens in the group C was significantly increased (P<0.05). The study indicates that adding GSE to the diet of laying hens in the late peak egg laying period can improve eggshell strength and egg qualification rate, reduce the feed to egg ratio, improve immune function, and increase the economic benefits of breeding, and the effect of adding 300 mg/kg GSE is obvious. [ABSTRACT FROM AUTHOR]

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Anhydroicaritin (1a), baohuoside (1b) and icariin (1c) were recognized as major pharmacologically active ingredients of Epimedium plants. Their primary means of acquisition were chemical isolation from plants. However, it suffers from low yield, environmental pollution and shortage of plants. Herein, to remedy these problems, biosynthesis was explored to obtain the three active ingredients. Fortunately, with SfFPT as 8-prenyltransferase, EpPF3RT and Ep7GT as glycosyltransferases, kaempferide (1) was transferred to 1a, 1b and 1c enzymatically. Thus, we report the details of this method. This approach represents a promising environmental friendly alternative for the production of these compounds from an abundant analogue. [ABSTRACT FROM AUTHOR]

Peridecalins C and D (1 and 2), one decalin and one oxygen-decalin containing polyketide-amino acid hybrids with 5/6/6 ring system, was isolated from a genetic mutant of Periconia sp. F-31. Their structures were elucidated through extensive spectroscopic data analysis, including 1 D/2D NMR and HR-MS spectra. Biosynthetically, two proposed Diels-Alder reactions are supposed to be involved in the skeleton construction of 1 and 2. [ABSTRACT FROM AUTHOR]

Background: The influence of external environmental factors on secondary metabolites of medicinal plants has always been studied. However, little is known about the relationships between endophytes and host metabolites, especially the relationship differences between different plant species. Thus, we used high-throughput sequencing methods to compare endophyte diversity from roots of two closely related species, Gentiana officinalis and G. siphonantha, from the same production area, and analyze the association with four secondary metabolites (Gentiopicroside, Loganic acid, Swertiamarine and Sweroside). Results: The fungal and bacteria communities' richness and diversity of G. siphonantha was higher than G. officinalis. Ascomycota and Proteobacteria were dominant fungal and bacterial phylum of the two closely related species. At the genus level, Tetracladium and Cadophora were dominant fungal genus in G. officinalis and G. siphonantha samples, respectively. While Pseudomonas was dominant bacterial genus in two closely related species, with relative abundances were 8.29 and 8.05%, respectively. Spearman analysis showed that the content of loganic acid was significantly positively correlated with endophytic fungi, the content of gentiopicroside, swertiamarine and sweroside were significantly positively correlated with endophytic bacteria in the two related species. PICRUSt and FUNGuild predictive analysis indicated that metabolism and saprotroph was primary function of endophytic bacteria and fungi in the two related species. Conclusion: Our results will expand the knowledge on relationships of plant-microbe interactions and offer pivotal information to reveal the role of endophytes in the production of Gentiana plant and its important secondary metabolite. [ABSTRACT FROM AUTHOR]

Purpose/aim of the study: Posterior circulation stroke (PCS) accounts for 20% of ischemic stroke, and vertebrobasilar stenosis is an important cause of PCS. Notably, not all patients with artery stenosis progress to ischemic stroke, and one of the important reason is that collateral circulation construction plays important protection role in this process. Clinical presentation: Here, we present the case of a 71-year-old male who presented with lightheadedness and three episodes of loss of consciousness after bilateral subclavian artery stenting. Digital subtraction angiography (DSA) demonstrated severe stenosis of the left vertebral artery, and the bilateral subclavian artery was kept open. The patient was then given the left vertebral artery stenting in an effort to resolve the vascular stenosis. As expected, he achieved a complete remission after stenting. However, 6 months later the patient suffered from loss of consciousness again. Repeat DSA confirmed restenosis of the left vertebral artery, and revealed a collateral flow to the left vertebral artery which fed by external carotid collateral branches. Then DSA was performed after 12 months, and another collateral circulation involving thyrocervical trunk was also found supplying flow to the left vertebral artery. In this process, the frequency of loss of consciousness gradually decreased as the collateral circulation construction. Conclusion: Through this case, we observe the whole process of the collateral circulation construction. Moreover, this case serves as a testament to the variability and complexity of vertebrobasilar arteriopathies, suggesting promotion of collateral flow offers the opportunity for outcome improvement. [ABSTRACT FROM AUTHOR]

Objective To investigate the efficacy and safety of intraoperative high-field MRI combined with fluorescence-guided glioma resection. Methods A total of 53 patients with glioma admitted to The Fisrt Bethune Hospital of Jilin University from June 2017 to June 2018 were enrolled, including 33 patients (62.26%) whose tumors were located in important brain functional areas (17 cases in motor area, 11 cases in language area, 5 cases in thalamus). Glioma resection was performed under fluorescence-guided (fluorescence guidance group, n = 28) and intraoperative high-field MRI combined with fluorescence-guided glioma resection (combined group, n = 25). Results Total tumor resection was performed in 42 cases (79.25%) and subtotal tumor resection in 11 cases (20.75%). Of the 33 patients whose tumors were located in important brain functional areas, total resection was performed in 25 cases (75.76%) and subtotal resection in 8 cases (24.24%). There were 12 cases (22.64%) of astrocytoma (WHO grade II), 17 cases (32.08%) of anaplastic astrocytoma (WHO grade III) and 24 cases (45.28%) of glioblastoma (WHO grade IV) were confirmed by postoperative pathology. There were 16 cases of speech disorder (30.19%), 21 cases of transient limb movement disorder (39.62%), 6 cases of mental disorder (11.32%), 8 cases of intracranial infection (15.09%), 2 cases of small epidural hemorrhage (3.77%), and no death after the operation. The operation time of combined group was longer than that of fluorescence guidance group [(3.79 ± 1.14) h vs. (2.53 ± 1.04) h; t = - 4.718, P = 0.000]. The tumor total resection rate in the combined group was higher than that in fluorescent guidance group [92% (23/25) vs. 67.86% (19/28); χ² = 4.681, P = 0.031], the WHO grade had significant difference between 2 groups (χ2 = 2.041, P = 0.036), but the tumor total resection rate in important brain functional areas [88.89% (16/18) vs. 60% (9/15); Fisher's exact probability: P = 0.101] and the incidence of postoperative complications [37.73% (20/53) vs. 62.26% (33/53); χ² = 0.179, P = 1.000] were no significant difference between 2 groups. In the mean follow-up of 9 months, 11 patients (20.75%) had tumor recurrence. There was no significant difference in the recurrence rate between combined group and fluorescence guidance group [12% (3/25) vs. 28.57% (8/28); χ² = 2.205, P = 0.138]. Conclusions Intraoperative high-field MRI combined with fluorescence guidance can significantly improve the total resection rate of glioma, while preserving important brain functional areas and neural structures as much as possible, improving the quality of life and prolonging the progression-free survival of patients. [ABSTRACT FROM AUTHOR]

Aims/Introduction: To examine the performance and identify the optimal threshold of vibration perception threshold (VPT) for diagnosing diabetic polyneuropathy (DPN) in a Chinese population according to multiple definitions of DPN as gold standards. Materials and Methods: VPT was determined in 421 Chinese individuals with type 2 diabetes, who simultaneously completed a questionnaire of neuropathic symptoms, and underwent the assessment of signs of peripheral neuropathy and electromyography tests. Three definitions of DPN (i.e., clinician‐diagnosed DPN, abnormal nerve conduction and confirmed DPN) were taken as reference gold standards. Results: Vibration perception threshold was a specific measure for all three groups of DPN outcomes, with the highest specificity noted for clinician‐diagnosed DPN (85.1%). The specificity for abnormal nerve conduction and confirmed DPN was 77.0 and 76.6%, respectively. The sensitivity of VPT was 67.0% for clinician‐diagnosed DPN, 66.5% for abnormal nerve conduction and 67.2% for confirmed DPN. The optimal cut‐off threshold for abnormal nerve conduction, as well as confirmed DPN, was VPT >14.9 V. The specificity and sensitivity of VPT >14.9 V as the cut‐off value for clinician‐diagnosed DPN were 85.6 and 66.2%, respectively. When taking clinician‐diagnosed DPN as the gold standard, the performance of VPT for diagnosing DPN was best with an area under the curve value of 0.804. Conclusions: VPT measured using the neurothesiometer had relatively high specificity and best performance for diagnosing DPN when clinician‐diagnosed DPN rather than abnormal nerve conduction was taken as the gold standard in a Chinese population. A VPT value of ≥15 V might be equally applicable for diagnosing DPN in a Chinese population. [ABSTRACT FROM AUTHOR]

The sensory evaluation outcome and the number of viable bacteria were used as the indicators for screening lactic acid bacteria with certain acid and bile tolerance and suitability for fermenting red kiwifruit. Through single factor and orthogonal experiments, the fermentation process conditions for red kiwifruit fermentation broth were determined and its flavor substances before and after fermentation were analyzed by GC-MS. The results showed that under the conditions of the selected Lactobacillus plantarum 11 and 154 strains inoculated at 3% and a ratio of 1:1, sugar added at 6%, material-to-water ratio of 2:1, and fermentation time of 22 h, the sensory evaluation score was 93.34, with the acidity being 97.47 °T, pH being 4.14 and the number of viable bacteria being 2.21*109 CFU/mL. The types of volatile substances increased significantly after fermentation (from 70 types before fermentation to 107 types after fermentation), among which, esters and acids changed greatly (from the original 11 types of esters and 4 types of acids to 18 types and 17 types, respectively). Based on the above indicators, the kiwifruit fermentation broth under the process conditions had a large number of viable cells, was rich in flavor substances, and tasted delicious. [ABSTRACT FROM AUTHOR]

The acid-producing, viscosity-increasing, and aroma-producing capacities and laboratory storage stabilities of ten strains of Lactobacillus delbrueckii subsp. bulgaricus were measured. The probiotic characteristics of the strains were also explored by monitoring their antibiotic resistance, antibacterial activities, and β-galactosidase (β-gal), α-galactosidase (α-gal), and lactate dehydrogenase (LDH) activities. Single-strain fermentation experiments show that the strain KSDB-1 had a short coagulation time (approximately 6.3 h), a lactic acid degree of 76.02ºT upon coagulation, and good acid-producing ability. The viscosity and water holding capacity (1305.67 mPa-s and 50.55%, respectively) were significantly higher than those of other strains (p<0.05). Aroma production of strains HDS-13, DDB14, and KSDB-1 was superior. Strain HDS-13 displayed a diacetyl content of 2.88 mg/L and an acetaldehyde content of up to 30.08 mg/L. These attributes could effectively improve the flavor of the yoghurt product. Probiotic tests show that all the ten tested strains were sensitive to most antibiotics and thus would be relatively safe to use. Strains HDS-13, DDB-14, HDB-1, HDS-18, and KSDB-1 could inhibit six pathogenic bacteria and effectively inhibited the growth of pathogenic intestinal bacteria. The LDH activities of strains HDS-12 and KSDB-1 were relatively high. The β-gal activities of strains HDS-12 and HDB-17 were relatively greater than that of the other strains. The α-gal activity of strain DDS-15 was significantly higher than those of other strains (p< 0.05), reaching 1.3263 U/mg. The collective data indicate that strain KSDB-1 has excellent fermentation properties and, to a certain degree, satisfactory probiotic properties. DDS-15 has potential in industrial application for yogurt fermentation. [ABSTRACT FROM AUTHOR]

The objective was to screen Lactobacillus strains with strong survivability in oro-gastrointestinal tract and adhesion abilities of intestinal mucins and Caco-2 cells, and their effect on absorption of short-chain fatty acids (SCFAs) by epithelial cells was studied. The survival rate of Lactobacillus strains was studied after exposure to oral stress, gastric stress and intestinal stress successively, and then their adhesion ability was also researched. The model of intestinal epithelial cells absorbing SCFAs was established, which was used to evaluate the effect of Lactobacillus strains on Caco-2 cells absorption of SCFAs. The survival rate of Lactobacillus plantarum L58, L67, L97, L123, and L198 and Lactobacillus fermentum L146 was significantly higher than others in oro-gastrointestinal tract (P < 0.05), which also showed high adhesion to mucins and Caco-2 cells. The model was successfully established with the Caco-2 cell line, which formed a polarized cell monolayer and developed tight junctions with an appropriate permeability coefficient for phenol red lower than 1 × 10–6 cm/s after culturing for 15 days, and the viability of Caco-2 cells was significantly higher than other concentrations when the content of propionic acid or butyric acid was 1 mmol/L in the model. The propionic acid content in Caco-2 cells inoculated with L. plantarum L58, L67, L97, L123, and L198 was significantly higher than that of cells without L. plantarum inoculation (P < 0.05), and the butyric acid content in cells inoculated with L. fermentum L146 was significantly higher than that of cells without inoculation (P < 0.05). Our results highlight that L. plantarum L58, L67, L97, L123, L198 and L. fermentum L146 are more resistant to oro-gastrointestinal conditions and their high adhesion to the intestine can enhance SCFAs uptake in intestinal epithelial cells. [ABSTRACT FROM AUTHOR]

Loess tablelands are widely distributed in the center of the Loess Plateau. The percentage of the Loess Plateau area that experiences seismic intensities greater than or equal to level VII is 54.21%. Because of the gravity of the loess slope and a large number of vertical pores, the fissures are mostly developed in the Loess Plateau. The fissures can easily cause slope instability subjected to earthquakes. Considering the structural characteristics of loess tableland slopes and earthquakes, a shaking-table test on slope models with and without fissures is conducted to study the dynamic response characteristics and the law of deformation and instability of the slopes under seismic action. The results indicate that the amplification factors of peak ground acceleration (PGA) in the vicinity of the fissures in the loess slope are significantly higher than those in the non-fissure slope, which reaches a maximum value of 3.6 at the shoulder of slope (measuring point A15). Dynamic earth pressures have stress concentration in the middle and upper part (0.7 times slope height) near the fissure, which affects the variation law of slope earth pressure. The failure mode of the fissure slope is as follows: fissure development, fissure expansion, soil collapse at the slope shoulder, shear failure at high-position on the slope, shear failure at low-position on the slope, and formation of new fissures at the edge of the tableland. [ABSTRACT FROM AUTHOR]

Objective: Subclavian steal syndrome results from hemodynamic impairment due to stenosis or occlusion of subclavian artery. Therefore, it is important for subclavian steal syndrome patients to assess hemodynamic status during endovascular therapy. Methods: Eleven subclavian steal syndrome patients undergoing endovascular therapy attended this study. Pressure wire was used to measure trans-stenosis pressure difference (ΔP). Digital subtraction angiography, Transcranial Doppler and Electronic sphygmomanometer were introduced to assess stenotic rate, steal grade and inter-arm systolic pressure difference, respectively. Clinical symptoms and restenosis were followed up after endovascular therapy. The associations of ΔP with stenotic rate, inter-arm pressure difference, steal degree, clinic symptoms and restenosis were analyzed in this paper. Results: Prior to the therapy, ΔP moderately correlated with stenotic rate (r = 0.757, p = 0.007) and inter-arm pressure difference (r = 0.701, p = 0.016). ΔP was ≥6 mmHg in all patients, and 6–9 mmHg for grade 1 steal and ≥10 mmHg for grade 2 and 3 steals. After the therapy, all patients had technique success, and 10 patients had clinic success, and 1 patient appeared restenosis. ΔP was ≤3 mmHg and steal disappeared in the patients with clinical success. ΔP was 18 mmHg and grade 3 steal still existed in one patient without clinical success. One patient with 1 mmHg of ΔP after therapy appeared restenosis in the follow-up. Conclusion: The trans-stenosis pressure difference is closely related to steal degree and clinical symptoms. The measurement of hemodynamic status by pressure wire is very useful to guide endovascular therapy in subclavian steal syndrome patients. However, the restenosis may still occur, even though the hemodynamic impairment is improved. [ABSTRACT FROM AUTHOR]

Bistachybotrysin K (1), one new phenylspirodrimane dimer with a central 6/7 oxygen heterocycle core, was isolated from the fungus Stachybotrys chartarum CGMCC 3.5365. Its structure was elucidated by extensive spectroscopic data and single-crystal X-ray diffraction. Compound 1 showed significant cytotoxicity against human tumor cell lines HCT116, NCI-H460, BGC823, Daoy, and HepG2 with IC50 values in the range of 1.1–4.7 µM. [ABSTRACT FROM AUTHOR]

Various bioactive polyketides have been found in Aloe barbadensis. However, the polyketide synthases (PKSs), which participate in biosynthesis of polyketides in A. barbadensis remain unknown. In this study, two type III PKSs (AbPKS1 and AbPKS2) were identified from A. barbadensis. AbPKS1 and AbPKS2 were able to utilize malonyl-CoA to yield heptaketides (TW93a and aloesone) and octaketides (SEK4 and SEK4b), respectively. AbPKS1 also exhibited catalytic promiscuity in recognizing CoA thioesters of aromatics to produce unusual polyketides. What Is more, a whole cell biocatalysis system with the capability of producing 26.4 mg/L of SEK4/SEK4b and 2.1 mg/L of aloesone was successfully established. [ABSTRACT FROM AUTHOR]

Three new phenylspirodrimanes derivatives named stachybotrysins H and I (1 and 2) and stachybotrin E (3), together with one known compound stachybotrylactam (4), were isolated from Stachybotrys chartarum CGMCC 3.5365. Their structures were determined by extensive NMR data and mass spectroscopic analysis. Compounds 1 and 2 showed inhibitory effect towards potassium channel Kv1.3 with IC50 values of 13.4 and 10.9 μM, respectively. [ABSTRACT FROM AUTHOR]

A chaos ant colony optimization algorithm for continuous domain is proposed based on chaos optimization theory and ant colony optimization algorithm. The searching abilities of optimization algorithms with different coding methods are compared, and the results indicate that the proposed algorithm has better performance than genetic algorithm and particle swarm optimization algorithm. Based on the non-dominated sorting concept and niching method, a multi-objective chaos ant colony optimization algorithm is also constructed and numerical results show that the improved algorithm performs well at solving multi-objective optimization problems. An optimal support vector regression model based on radial basis kernel function is developed for the small sample size and nonlinear characteristics of streamlined head optimization. On the basis of the above work, a multi-objective optimization design for the aerodynamic head shape of high-speed train is developed using a modified vehicle modeling function parametric approach. The optimization results demonstrate that the new optimization design method has exceptional searching abilities and high prediction accuracy. After optimization, the aerodynamic drag of the simplified train with three carriages is reduced by 10.52% and the aerodynamic lift of the tail car is reduced by 35.70%. The optimization approach proposed in the present paper is simple yet efficient and sheds light on the engineering design of aerodynamic shape of high-speed trains. [ABSTRACT FROM AUTHOR]

Morpholine is a common chemical used as emulsifier in the preparation of wax coatings for some fruit to help them remain fresh and protect against insects and fungal contamination. It has been reported that morpholine has acute toxic effects on rodents. In the present study, morpholine concentrations were analysed in fruits (citrus fruits, apples, strawberries and grapes) and juices (apple juice and orange juice) in order to determine dietary exposure among the Chinese population. A total of 732 fruit and juice samples were collected during 2015-2016, which covered major foods in China. Fruit and juice consumption data were taken from China National Nutrient and Health Survey (2002) and include data from 16,407 fruit or juice consumers. It was found that mean dietary exposure to morpholine residues from fruits and/or juices for general Chinese consumers and children 2-6 years old were 0.42 and 1.24 µg/kg bw/day, respectively. The 97.5% intake in general Chinese consumers and children 2-6 years old were 2.25 and 6.90 µg/kg bw/day, respectively. The primary food sources of the morpholine dietary intake of general Chinese consumers were citrus fruits (57.4%) and apples (40.8%). These findings suggested that dietary exposure to morpholine in the Chinese population was lower than the acceptable daily intake of morpholine, and there are no health concerns. [ABSTRACT FROM AUTHOR]

Previous studies indicate a preliminary association between age and circadian blood pressure (BP) variation. This association would be affected by confounding factors in real-world populations. The authors investigated whether this is a convincingly independent association in a real-world population of adults with hypertension. Clinical data and findings of 24-hour ambulatory BP monitoring were obtained from 297 consecutive adults with hypertension (60.19±0.77 years). BP dipping patterns were categorized based on the percentage of nocturnal BP drop. Multivariate linear regression analysis identified an independent correlation between age and percentage of nocturnal systolic BPdrop (β=-7.296; 95% CI, -10.430 to -4.162 [P<.001]). Reverse dippers were the oldest and extreme dippers were the youngest. A significant age difference was noted among patients grouped into four BP dipping patterns with and without adjustments for sex, body mass index, drugs, diabetes mellitus, smoking, 24-hour mean heart rate, and 24-hour mean systolic and diastolic BP. [ABSTRACT FROM AUTHOR]

Two new lanostane triterpenoids (1 and 2), two new ergostane-type steroids (3 and 4) together with two known lanostane triterpenoids (5 and 6) and one known steroid (7) were isolated from the cultured mycelia of Ganoderma capense (CGMCC 5.71). Their structures were determined on the basis of extensive spectroscopic (HRESIMS, 1D NMR, 2D NMR) data analyses. Compound 1 exhibited moderate cytotoxic activity against the human cancer cell line NCI-H1650 with an IC50 value of 22.3 μM, and 7 displayed cytotoxic activity against the human cancer cell line HCT116 with an IC50 value of 17.4 μM. In addition, compounds 2, 3, 5, and 6 displayed weak anti-HIV activity with IC50 values of 23.5, 46.7, 21.6, and 30.1 μM, respectively. [ABSTRACT FROM AUTHOR]

Glucuronidation is an important and popular metabolic reaction in vivo of drugs. The further evaluation of biological activity and toxicity of glucuronides is necessary in the course of the drug research and development. However, the synthesis of glucuronides is limited by the lack of efficient approach. Herein, we have developed a new glucuronide synthesis method using plant uridine diphosphate-dependent glucuronosyltransferases (UGTs), UGT88D4, UGT88D7, and EpGT8, enabling the convenient preparation for corresponding O-glucuronide metabolites (1a, 2a, 3a, and 3b) in milligram scale of two neurological active agents, IMM-H004 (1) and FLZ (2). Their structures were characterized by spectroscopic data analyses. [ABSTRACT FROM AUTHOR]

1. UDP-glucuronosyltransferases (UGTs) are important drug-metabolizing enzymes (DMEs) catalyzing the glucuronidation elimination of various xenobiotics and endogenous substances. Endogenous substances are important regulators for the activity of various UGT isoforms. Triiodothyronine (T3) and thyroxine (T4) are important thyroid hormones essential for normal cellular differentiation and growth. The present study aims to elucidate the inhibition behavior of T3 and T4 on the activity of UGT isoforms. 2. In vitrorecombinant UGTs-catalyzed glucuronidation of 4-methylumbelliferone (4-MU) was used to screen the inhibition potential of T3 and T4 on the activity of various UGT isoforms. Initial screening results showed that T4 exerted stronger inhibition potential than T3 on the activity of various UGT isoforms at 100 μM. Inhibition kinetics was determined for the inhibition of T4 on the representative UGT isoforms, including UGT1A1, -1A3, -1A7, -1A8, -1A10 and -2B7. The results showed that T4 competitively inhibited the activity of UGT1A1, -1A3, -1A7, 1A10 and -2B7, and noncompetitively inhibited the activity of UGT1A8. The inhibition kinetic parameters were calculated to be 1.5, 2.4, 11, 9.6, 4.8 and 3.0 μM for UGT1A1, -1A3, -1A7, -1A8, -1A10 and -2B7, respectively.In silicodocking method was employed to demonstrate why T4 exerted stronger inhibition than T3 towards UGT1A1. Stronger hydrogen bonds and hydrophobic interaction between T4 and activity cavity of UGT1A1 than T3 contributed to stronger inhibition of T4 towards UGT1A1. 3. In conclusion, more clinical monitoring should be given for the patients with the elevation of T4 level due to stronger inhibition of UGT isoforms-catalyzed metabolism of drugs or endogenous substances by T4. [ABSTRACT FROM AUTHOR]

Drug delivery systems (DDSs) commonly employ arginine–glycine–aspartic acid (RGD) peptides with polyethylene glycol (PEG)-dependent enhanced permeability and retention (EPR) effect to optimise tumour-targeting. However, the PEG dilemma and integrin saturation obstacle are major challenges. To address these issues, we constructed a novel, nano-sized DDS by encapsulating doxorubicin (DOX)-loaded folic acid derivatives of polyamidoamine dendrimer (PAMAM G5.0) in cyclic RGD-tyrosine-lysine pentapeptide (c[RGDyK])-modified liposomes (RGD-SL[FND/DOX]), prepared using thin-film hydration, film-dispersion and hydration-sonication. The liposomes were PEGylated, sterically stabilised and pH-sensitive.In vitro, RGD-SL[FND/DOX] showed pH-sensitive holistic FND/DOX release, and pH-dependent uptake and cytotoxicity in human cancer KB cells. At pH 7.4, RGD-SL[FND/DOX] demonstrated greater cellular uptake and cytotoxicity than relevant control formulations (except FND/DOX) did, although this advantage disappeared at pH 6.5.In vivo, RGD-SL[FND/DOX] inhibited S180 sarcoma xenografted tumour growth in Kunming mice more effectively than FND/DOX did. These findings demonstrate the feasibility of constructing double-stage tumour-targeting nano-sized DDSs such as RGD-SL[FND/DOX]. c[RGDyK] and the EPR effect, facilitated by the particle size (about 110 nm) and PEGylation, helped to target the DDS to the tumour tissue, while the subsequent pH-dependent release of FND/DOX and folic acid-mediated endocytosis specifically targeted the tumour cells, thereby overcoming the PEG dilemma and integrin saturation obstacle. [ABSTRACT FROM AUTHOR]

Three new sesquiterpenoids trichoacorenols B–C and cyclonerodiol B (1–3), along with three known ones (4–6), were isolated from the mangrove plant endophytic fungusTrichodermasp. Xy24 using various column chromatography techniques. The structures of these compounds were determined on the basis of extensive spectroscopic data analyses. Compounds1,2,4, and5were four acorane sesquiterpenes,3and6were two monocyclic sesquiterpenediols. Compounds3and5exhibited significant neural anti-inflammatory activity by inhibiting LPS-induced NO production in BV2 cells with the inhibitory rates of 75.0% and 39.2% at 0.1 μM, respectively, which are more potent than curcumin, a positive control with the inhibitory rate of 21.1% at 0.1 μM. [ABSTRACT FROM PUBLISHER]

Praeruptorin A (PA) and B (PB) are two important compounds isolated from Bai-hua Qian-hu and have been reported to exert multiple biochemical and pharmacological activities. The present study aims to determine the inhibition of PA and PB on the activity of important phase II drug-metabolizing enzymes uridine 5'-diphospho-glucuronosyltransferase (UGTs) isoforms. In vitro UGT incubation system was used to determine the inhibition potential of PA and PB on the activity of various UGT isoforms. In silico docking was performed to explain the inhibition difference between PA and PB towards the activity of UGT1A6. Inhibition behaviour was determined, and in vitro-in vivo extrapolation was performed by using the combination of in vitro inhibition kinetic parameter (Ki ) and in vivo exposure level of PA. Praeruptorin A (100 μM) exhibited the strongest inhibition on the activity of UGT1A6 and UGT2B7, with 97.8% and 90.1% activity inhibited by 100 μM of PA, respectively. In silico docking study indicates the significant contribution of hydrogen bond interaction towards the stronger inhibition of PA than PB towards UGT1A6. Praeruptorin A noncompetitively inhibited the activity of UGT1A6 and competitively inhibited the activity of UGT2B7. The inhibition kinetic parameter (Ki ) of PA towards UGT1A6 and UGT2B7 was calculated to be 1.2 and 3.3 μM, respectively. The [I]/Ki value was calculated to be 15.8 and 5.8 for the inhibition of PA on UGT1A6 and UGT2B7, indicating high inhibition potential of PA towards these two UGT isoforms in vivo. Therefore, closely monitoring the interaction between PA and drugs mainly undergoing UGT1A6 or UGT2B7-catalyzed metabolism is very necessary. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This study evaluated the genetic diversity and origin of Daweishan Mini chickens using mtDNA sequence polymorphism. Blood samples from 30 Daweishan Mini chickens were collected. The complete D-loop was PCR amplified, sequenced and compared with the DNA data of five Red Junglefowl (Gallus gallus) subspecies. Eighteen variable sites that defined six haplotypes were observed. The six haplotypes were clustered into four clades (A, B, D and E), of which clade A and B were dominant. Clades Aand B were clustered withG.g. spadiceus, indicating these two clades may have originated from this subspecies. These results show there is diversity in the middle of the mtDNA D-loop, and indicate there are multiple maternal origins for Daweishan Mini chickens. It appears thatG.g. spadiceuscontributed more to the evolution of the Daweishan Mini chickens breed than the other four subspecies tested here. [ABSTRACT FROM AUTHOR]

Background and objectives: The clinical features and efficacies of antivirals for children with hepatitis C virus (HCV) infections that are acquired through different transmission routines are poorly understood worldwide. This study investigated the clinical characteristics of children who were infected via iatrogenic means and analyzed the efficacy of antiviral therapy in children with chronic hepatitis C (CHC). Methods: In total, 256 children with HCV infections aged 1 to 5 years were enrolled and surveyed. Interferon-α plus ribavirin was administered to 162 children with CHC for 24 or 48 weeks. The sustained virologic response (SVR) at 24 weeks post-treatment was determined. Results: The median duration of infection was 11.5 (range 6-24) months. The median age was 2.7 years, and 64.5 % of the subjects were male. Ninety-three children (36.3 %, 93/256) exhibited spontaneous resolution of the HCV infection. The remaining 163 (63.7 %) were HCV RNA-positive and had HCV genotypes 1b and 2a, which were identified in 42 and 58 %, respectively, of the 133 tested children. Liver biopsies were performed in all HCV RNA-detectable children. A total of 23.9 % cases exhibited grade 2 activity, and 30.1 % exhibited stage 2/3 liver fibrosis. The serum HCV RNA levels were positively correlated with the aminotransferases. Of the 162 treated CHC children, 158 (97.5 %) achieved SVR. The side effects were mild, and 158 (97.5 %) of the treated patients tolerated the treatment well. Conclusions: This study revealed that histological liver disease can be present within 6-24 months of acquiring an HCV infection in children aged 1-5 years. Interferon-α plus ribavirin therapy is a highly effective and cost-effective means of managing children with early-stage chronic HCV infection. [ABSTRACT FROM AUTHOR]

Long noncoding RNAs (lncRNAs), which are prevalently transcribed in the genome, are involved in a variety of biological functions, yet little is known about their abundance in human cumulus cells (CCs) during oocyte development. Here, we describe the expression profile of lncRNAs in 3 pairs of cumulus cells from mature oocytes that result in high-quality embryo (H-CCs) and from oocytes that result in poor-quality embryo (P-CCs) using microarray analysis. In this study, a total of 20 563 lncRNAs were expressed in human CCs. One hundred and twenty four lncRNAs were consistently upregulated, and 509 lncRNAs were consistently downregulated in all samples analyzed (fold change ≥ 2.0, P < .05). Quantitative real-time polymerase chain reaction (qRT-PCR) was used to validate 5 upregulated and 7 downregulated lncRNAs. The qRT-PCR results in the study were confirmed to be consistent with the microarray results. Network analysis was used for further research. The results displayed the differentially expressed lncRNAs in P-CCs between H-CCs, which suggested that lncRNAs may contribute to the processes of oocyte and early embryo development. [ABSTRACT FROM AUTHOR]

Objective: To further evaluate the stability of different batches of culture medium by analyzing the IVF outcomes. Methods: Clinical data were collected from August 2011 to September 2012 in our IVF centre. Patients' characteristics were summarized as younger than 35 years, normal ovarian reserve, using long protocol for ovulation, and more than 5 oocytes per cycles. There were 18 batches of the culture medium according to the cleavage stage (18 groups). Six batches (6 groups) were randomly selected. General clinical features and IVF outcomes were compared. Results: There were no significant differences in the average age, the number of previous IVF, basal FSH level, body mass index (BMI), and endometrial thickness of hCG day, among the six groups (P>0.05). There were no significant differences in the average number of oocyte, oocyte maturation rate, fertilization rate, cleavage rate (P>0.05) among the groups. The high-quality embryo rate was different among the groups (P<0.05). However, there were no significant differences in the average number of embryos transferred, pregnancy rate, miscarriage rate among the groups (P>0.05). Conclusions: IVF outcomes from different batches of the embryonic culture medium are stable, suggesting the stability of the overall quality control system in our IVF laboratory. [ABSTRACT FROM AUTHOR]

Objectives: To explore the anatomy of the plantar aponeurosis (PA) and its biomechanical effects on the first metatarsophalangeal (MTP) joint and foot arch. Methods: Anatomic parameters (length, width and thickness of each central PA bundle and the main body of the central part) were measured in 8 cadaveric specimens. The ratios of the length and width of each bundle to the length and width of the central part were used to describe these bundles. Six cadaveric specimens were used to measure the range of motion of the first MTP joint before and after releasing the first bundle of the PA. Another 6 specimens were used to evaluate simulated static weight-bearing. Changes in foot arch height and plantar pressure were measured before and after dividing the first bundle. Results: The average width and thickness of the origin of the central part at the calcaneal tubercle were 15.45 mm and 2.79 mm respectively. The ratio of the length of each bundle to the length of the central part was (from medial to lateral) 0.29, 0.30, 0.28, 0.25, and 0.27, respectively. Similarly, the ratio of the widths was 0.26, 0.25, 0.23, 0.19 and 0.17. The thickness of each bundle at the bifurcation of the PA into bundles was (from medial to lateral) 1.26 mm, 1.04 mm, 0.91 mm, 0.84 mm and 0.72 mm. The average dorsiflexion of the first MTP joint increased 10.16° after the first bundle was divided. Marked acute changes in the foot arch height and the plantar pressure were not observed after division. Conclusions: The first PA bundle was not the longest, widest, or the thickest bundle. Releasing the first bundle increased the range of motion of the first MTP joint, but did not acutely change foot arch height or plantar pressure during static load testing. [ABSTRACT FROM AUTHOR]

Intensive turbulence exists in the wakes of high speed trains, and the aerodynamic performance of the trailing car could deteriorate rapidly due to complicated features of the vortices in the wake zone. As a result, the safety and amenity of high speed trains would face a great challenge. This paper considers mainly the mechanism of vortex formation and evolution in the train flow field. A real CRH2 model is studied, with a leading car, a middle car and a trailing car included. Different running speeds and cross wind conditions are considered, and the approaches of unsteady Reynold-averaged Navier-Stokes (URANS) and detached eddy simulation (DES) are utilized, respectively. Results reveal that DES has better capability of capturing small eddies compared to URANS. However, for large eddies, the effects of two approaches are almost the same. In conditions without cross winds, two large vortex streets stretch from the train nose and interact strongly with each other in the wake zone. With the reinforcement of the ground, a complicated wake vortex system generates and becomes strengthened as the running speed increases. However, the locations of flow separations on the train surface and the separation mechanism keep unchanged. In conditions with cross winds, three large vortices develop along the leeward side of the train, among which the weakest one has no obvious influence on the wake flow while the other two stretch to the tail of the train and combine with the helical vortices in the train wake. Thus, optimization of the aerodynamic performance of the trailing car should be aiming at reducing the intensity of the wake vortex system. [ABSTRACT FROM AUTHOR]

Objective To discuss the operative methods and curative effect of calcaneal tuberosity fracture. Methods A retrospective study was done to analyze 15 patients with calcaneal tuberosity fracture who received surgical management between January 2008 and June 2011. There were nine males and six females, with the age ranging from 31 to 68 years (average, 51.4 years). All the patients had unilateral acute injury, with the left foot in 7 cases and the right foot in 8 cases. According to the Beavis classification, there were three cases in type I and 12 cases in type II. All the cases in type I and 10 cases in type II were treated with open reduction and screw fixation. The other two cases in type II with larger fragment involving a portion of the subtalar joint were treated with plate and screw fixation. The effect of the treatment was assessed according to the ankle and hindfoot score system of American Orthopaedic Foot and Ankle Society ( AOFAS) after the operation. Results Ten patients were followed up for 12 to 36 months (average, 20 months). The healing time in these patients ranged from 8 to 25 weeks (average, 12 weeks). The postoperative score ranged from 47 to 100 points (average, 91.1 points). Seven cases were rated as excellent, two as good, and one as poor. The rate of excellent and good was 90%. Necrosis of skin and soft tissue and exposure of the plate happened in one patient, who eventually healed after 3 weeks by debridement with plate preserved and peroneal artery perforator flap transplantation. Loss of reduction happened to another patient, who was treated with revision surgery by open reduction and screw fixation again. Conclusion To patients with obvious fracture displacement, whose soft tissues are irritated severely, emergency open reduction and internal fixation operation should be offered to prevent the necrosis of the flaps as far as possible. To patients with small fractures, it is advisable to choose open reduction and large diameter screw fixation, while plate and screw fixation may be better for the patients with large fragments, especially for those with the fracture line extending to the subtalar joint. [ABSTRACT FROM AUTHOR]

The aim of this study was to detect MTA2 expression in pancreatic ductal adenocarcinoma (PDA) and to analyze its association with prognosis of PDA patients. MTA2 mRNA and protein expression were determined by real-time quantitative reverse transcriptase-polymerase chain reaction and immunohistochemistry in specimens of primary cancer and their adjacent noncancerous tissues in PDA patients. We found that MTA2 mRNA and protein expression levels were both significantly upregulated in PDA lesions compared with adjacent noncancerous tissues. Immunohistochemistry showed that high MTA2 expression was correlated with poor tumor differentiation, TNM stage, and lymph node metastasis. Kaplan-Meier survival analysis showed that patients with high expression levels of MTA2 showed lower overall survival rate than those with low expression levels. Multivariate analysis showed that high MTA2 protein expression was an independent prognostic factor for PDA patients. Our study suggests that overexpression of MTA2 may play an important role in the progression of PDA and MTA2 expression may serve as a biomarker for poor prognosis for PDA. [ABSTRACT FROM AUTHOR]

The current study aims to develop a stable pH-sensitive drug delivery system. First, cleavable polyethylene glycol-α-tocopherol hemisuccinate (PEG-THS) was synthesized. Conventional pH-sensitive vesicles composed of the Tris salt of α-tocopherol hemisuccinate (THST) were then prepared using the detergent removal technique. The vesicles had a mean particle size of (163.8 ± 5.5) nm and a zeta potential of −74.5 ± 6.4 mV. The THST vesicles were then modified using PEG-THS or uncleavable PEG-cholesterol (PEG-CHOL) (THST/PEG-lipids, 100:6 molar ratio). The mean vesicle particle size and absolute zeta potential decreased with increasing PEG-THS proportion. When the pH was decreased, the vesicle particle size and calcein release rate increased. The THST vesicles were initially Ca-unstable but exhibited significantly improved stability after modification with PEG-THS, especially at PEG-lipid ratios above 6%. Incubation in an acid serum increased the calcein release rate of conventional THST vesicles to 45 ± 1.98% at 10 min. However, the release rate of the PEG-CHOL vesicles remained low. The calcein release rate of PEG-THS vesicles was between those of conventional and PEG-CHOL-V. Therefore, PEG-THS can protect vesicles in serum and reconstitute their pH sensitivity in acidic conditions. Cleavable PEG-THS can be used in stable pH-sensitive preparations without loss of pH sensitivity. Free calcein and conventional vesicles eliminated from the plasma soon after injection, as well as the half-life ( t ) and area under the curve of PEG-THS-V encapsulating calcein, were dramatically increased. This phenomenon indicates that the use of PEG-lipid derivatives has gained a favorably long circulation effect in mice. [ABSTRACT FROM AUTHOR]

Summary: Background and purpose: Physical frailty may predict many adverse events, and it is important to identify a stable and easy clinical measurement to assess physical function for Chinese elders. Methods: We modified the mini-Physical Performance Test (PPT) of Wilkins et al by adding one-leg standing test and simulating the 15 meters timed walk with a 6 meters timed walk to construct the Chinese version mini-PPT (CM-PPT). A total of 170 elderly individuals were tested by CM-PPT and mini-mental state examination (MMSE). Twenty-three randomly chosen individuals were tested again by the same rater and another rater in a week, and the 15 meters timed walk and the Barthel index (BI) were also evaluated. Results: The Cronbach’s coefficient of CM-PPT was 0.868, and the test–retest and inter-rater reliability were 0.96 and 0.99, respectively (p <0.001). When the diseases influencing PPT other than cognitive disorders were excluded, CM-PPT was associated with MMSE (r =0.420, p <0.01) and age (r =−0.649, p <0.001) in 47 participants. CM-PPT was also correlated with BI (r =0.667, p <0.001), while 65% of the participants acquired full marks for BI and only 9% of the participants did so for CM-PPT. Of the 170 participants, 31 had different results between tandem and one-leg positions (p <0.001). Of these participants, 90% were only able to do tandem position and 10% were only able to do one-leg position. There was no difference between the scores in 6- and 15 meters timed walk (p =0.49). Conclusion: CM-PPT is a stable test and more sensitive than the BI. It is moderately associated with MMSE in the elderly without diseases influencing PPT other than cognitive disorders. [Copyright &y& Elsevier]

In order to study the unsteady aerodynamics effects in railway tunnels, the 3D Reynolds average Navier-Stokes equations of a viscous compressible fluid are solved, and the two-equation k- ɛ model is used in the simulation of turbulence, while the dynamic grid technique is employed for moving bodies. We focus on obtaining the changing tendencies of the aerodynamic force of the train and the aerodynamic pressures on the tunnel wall and train surface, and discovering the relationship between the velocity of the train and the intensity of the micro pressure wave at the tunnel exit. It is shown that the amplitudes of the pressure changes in the tunnel and on the train surface are both approximately proportional to the square of the train speed, so are the microwave and the drag of the train. [ABSTRACT FROM AUTHOR]

With the development of high-speed train, it is considerably concerned about the aerodynamic characteristics and operation safety issues of the high-speed train under extreme weather conditions. The aerodynamic performance of a high-speed train under heavy rain and strong crosswind conditions are modeled using the Eulerian two-phase model in this paper. The impact of heavy rainfall on train aerodynamics is investigated, coupling heavy rain and a strong crosswind. Results show that the lift force, side force, and rolling moment of the train increase significantly with wind speed up to 40 m/s under a rainfall rate of 60 mm/h. when considering the rain and wind conditions. The increases of the lift force, side force, and rolling moment may deteriorate the train operating safety and cause the train to overturn. A quasi-static stability analysis based on the moment balance is used to determine the limit safety speed of a train under different rain and wind levels. The results can provide a frame of reference for the train safe operation under strong rain and crosswind conditions. [ABSTRACT FROM AUTHOR]

The influence of sandstorms on train aerodynamic performance and safe running was studied in response to the frequent occurrence of sandstorm weather in north China. An Eulerian two-phase model in the computational fluid dynamic (CFD) software FLUENT, validated with published data, was used to solve the gas-solid multiphase flow of a sandstorm around a train. The train aerodynamic performance under different sandstorm levels and no sand conditions was then simulated. Results showed that in sandstorm weather, the drag, lift, side forces and overturning moment increase by variable degrees. Based on a numerical analysis of aerodynamic characteristics, an equation of train stability was also derived using the theory of moment balance from the view of dynamics. A recommended speed limit of a train under different sandstorm levels was calculated based on the stability analysis. [ABSTRACT FROM AUTHOR]

Intravenously injectable emulsion of ββ-elemene was studied in detail. Both blank and ββ-elemene-loaded microemulsions were prepared using a simple water titration method. The pseudoternary phase diagram was constructed for the optimization of microemulsion. The loading capacity test, dilutability test, and especially the influence of antioxidants were conducted for further optimization of ββ-elemene-loaded microemulsion. Transmission electron microscope showed intact and spherical microemulsion droplets. Conductivity and viscosity measurements were used to study the phase behaviors of ββ-elemene-loaded microemulsions, providing convincing explanation. In vitro release study showed that ββ-elemene was steadily released until 12 h, which most fitted the first order. [ABSTRACT FROM AUTHOR]

Background: The objective of this work was to study the preparation and characteristics of zedoary turmeric oil (ZTO), a traditional Chinese oily medicine, loaded with nanostructured lipid carriers (NLCs). Method: Aqueous dispersions of NLC were successfully prepared by melt-emulsification technique using Crodamol SS as the solid lipid, Miglyol 812N as the liquid oil, and soybean phosphatidylcholine (SbPC) as the emulsifier. Properties of NLC such as the particle size and its distribution, the transmission electron microscope (TEM), drug entrapment efficiency (EE), and drug release behavior were investigated, respectively. The Germacrone blood concentration after intravenous administration of ZTO–NLC was determined and compared with that of ZTO-injection. Result: As a result, the drug EEs were improved by adding the liquid lipid into the solid lipid of nanoparticles (SLNs). In vitro drug release experiments indicated that the prepared NLC could enhance the drug release rate over the SLN, and the drug release rate could be adjusted by the liquid lipid content in lipid nanospheres. X-ray and differential scanning calorimetry (DSC) measurements revealed that imperfect crystallization occurred in the inner core of the NLC particles. Conclusion: The results suggest that the presented NLC system might be a promising intravenous dosage form of water-insoluble oily drugs. [ABSTRACT FROM AUTHOR]

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Microdialysis was used together with HPLC to monitor the local concentration of pingyangmycin hydrochloride (PYM) after embolizing rabbit ear-veins with an injectable sustained release formulation, PYM-Zein/PYM-Zein-sucrose acetate isobutyrate (SAIB), in situ gel. The dialysis probe was perfused at 2 µL/min. The in vivo recovery was 46.6 3.1% ( n = 4). The samples were injected directly into HPLC. PYM was detected using UV detector at 291 nm. Separation from other components in the dialysate was performed using a Discovery® RP-Amide C16 column within 12 min. The response for PYM in the dialysate was linear ( r2 > 0.996) over the range of 2.5-212 µg/mL. The limit of detection and limit of quantitation of PYM in the dialysate were 0.4 and 1.5 µg/mL, respectively. The results demonstrated that the in situ gel of PYM-Zein-SAIB could extend the release of PYM to 4 days. SAIB could significantly cut down the initial burst of PYM from the in situ gels ( p < 0.05). Copyright © 2006 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Simple Summary: Nectar robbers affect plant fitness in different degrees and in different ways, potentially constituting an important part of pollination interactions. While the negative effects of nectar robbing on plant reproductive success have been widely reported, the positive effects are quite unclear. Hence, our study was designed to assess the effects of nectar robbers on reproductive success of Symphytum officinale. This will help in understanding the evolutionary significance of mutualistic relationships between plants and their visitors. Nectar robbers, which affect plant fitness (directly or indirectly) in different degrees and in different ways, potentially constitute a significant part of mutualistic relationships. While the negative effects of nectar robbing on plant reproductive success have been widely reported, the positive effects remain unknown. The target of our study was to evaluate the effects of nectar robbers on the reproductive success of Symphytum officinale (Boraginaceae). We observed the behavior, species and times of visitors in the field, and we assessed the effect of nectar robbers on corolla abscission rate and time. To test the fitness of corolla abscission, we detected the changes in stigma receptivity, pollen viability, pollen amount and appendage opening size along with the time of flower blossom. The flowering dynamics and floral structure were observed to reveal the mechanism of self-pollination. Finally, pollen deposition seed set rate and fruit set rate were determined to estimate the effect of nectar robbers on reproduction success. We observed 14 species of visitors and 2539 visits in 50 h of observation; 91.7% of them were nectar robbers. The pressure and nectar removal of nectar robbers significantly promoted corolla abscission during a period when pollen grains are viable and the stigma is receptive. In addition, corolla abscission significantly increased the pollen deposition and seed setting rate. Our results demonstrate that nectar robbing contributes to enhancing seed production and positively and indirectly impacts the reproductive success of S. officinale. This mechanism involved the movement of anthers and indirect participation by nectar robbers, which was rarely investigated. Considering the multiple consequences of nectar robbing, understanding the impact of nectar robbers on plant reproduction is essential to comprehend the evolutionary importance of relationships between plants and their visitors. [ABSTRACT FROM AUTHOR]