bluuebunny/crossref_metadata_2025 huggingface dataset:
Increased Serum CD14 Level Is Associated with Depletion of TNF-α in Monocytes in Migraine Patients during Interictal Period
Authors: Michalak Slawomir , Kalinowska-Lyszczarz Alicja , Wegrzyn Danuta , Niezgoda Adam , Losy Jacek , Osztynowicz Krystyna , Kozubski Wojciech
Published: May 2017

The aim of the present study was to investigate the levels of circulating CD14 in relation to the expression of tumor necrosis factor alpha (TNF-α) in monocytes, and serum levels of TNF-α and macrophage inflammatory protein-1 (MIP-1) in migraine patients. Numerous studies revealed controversial changes in the components of the immune system during attacks and the interictal period in migraine patients. Our study included 40 migraineurs and 39 controls. The levels of TNF-α, MIP-1 and CD14 were measured in peripheral monocytes and in sera with the Enzyme-Linked Immunosorbent Assay (ELISA) method, and the monocyte expression of TNF-α was also analysed by immunostaining. Serum CD14 concentrations were higher and the expression of TNF-α in monocytes was decreased in migraineurs. The serum MIP-1 level correlated with Verbal Rating Scale (VRS); the MIP-1:CD14 ratio in monocytes correlated with Visual Analogue Scale (VAS); the MIP-1:CD14 ratio correlated with Migraine Severity (MIGSEV)-Pain scores; and serum CD14 concentration correlated with migraine duration in years. Increased serum CD14 and depletion of TNF-α in monocytes can orchestrate other components of the immune system during the interictal period.
Fasting Enhances the Contrast of Bone Metastatic Lesions in 18F-Fluciclovine-PET: Preclinical Study Using a Rat Model of Mixed Osteolytic/Osteoblastic Bone Metastases
Authors: Oka Shuntaro , Kanagawa Masaru , Doi Yoshihiro , Schuster David , Goodman Mark , Yoshimura Hirokatsu
Published: May 2017

18F-fluciclovine (trans-1-amino-3-18F-fluorocyclobutanecarboxylic acid) is an amino acid positron emission tomography (PET) tracer used for cancer staging (e.g., prostate and breast). Patients scheduled to undergo amino acid-PET are usually required to fast before PET tracer administration. However, there have been no reports addressing whether fasting improves fluciclovine-PET imaging. In this study, the authors investigated the influence of fasting on fluciclovine-PET using triple-tracer autoradiography with 14C-fluciclovine, [5,6-3H]-2-fluoro-2-deoxy-d-glucose (3H-FDG), and 99mTc-hydroxymethylene diphosphonate (99mTc-HMDP) in a rat breast cancer model of mixed osteolytic/osteoblastic bone metastases in which the animals fasted overnight. Lesion accumulation of each tracer was evaluated using the target-to-background (muscle) ratio. The mean ratios of 14C-fluciclovine in osteolytic lesions were 4.6 ± 0.8 and 2.8 ± 0.6, respectively, with and without fasting, while those for 3H-FDG were 6.9 ± 2.5 and 5.1 ± 2.0, respectively. In the peri-tumor bone formation regions (osteoblastic), where 99mTc-HMDP accumulated, the ratios of 14C-fluciclovine were 4.3 ± 1.4 and 2.4 ± 0.7, respectively, and those of 3H-FDG were 6.2 ± 3.8 and 3.3 ± 2.2, respectively, with and without fasting. These results suggest that fasting before 18F-fluciclovine-PET improves the contrast between osteolytic and osteoblastic bone metastatic lesions and background, as well as 18F-FDG-PET.
Nobiletin Inhibits Angiogenesis by Regulating Src/FAK/STAT3-Mediated Signaling through PXN in ER+ Breast Cancer Cells
Authors: Sp Nipin , Kang Dong , Joung Youn , Park Jong , Kim Wan , Lee Hak , Song Ki-Duk , Park Yeong-Min , Yang Young
Published: May 2017

Tumor angiogenesis is one of the major hallmarks of tumor progression. Nobiletin is a natural flavonoid isolated from citrus peel that has anti-angiogenic activity. Steroid receptor coactivator (Src) is an intracellular tyrosine kinase so that focal adhesion kinase (FAK) binds to Src to play a role in tumor angiogenesis. Signal transducer and activator of transcription 3 (STAT3) is a marker for tumor angiogenesis which interacts with Src. Paxillin (PXN) acts as a downstream target for both FAK and STAT3. The main goal of this study was to assess inhibition of tumor angiogenesis by nobiletin in estrogen receptor positive (ER+) breast cancer cells via Src, FAK, and STAT3-mediated signaling through PXN. Treatment with nobiletin in MCF-7 and T47D breast cancer cells inhibited angiogenesis markers, based on western blotting and RT-PCR. Validation of in vitro angiogenesis in the human umbilical vein endothelial cells (HUVEC) endothelial cell line proved the anti-angiogenic activity of nobiletin. Electrophoretic mobility shift assay and the ChIP assay showed that nobiletin inhibits STAT3/DNA binding activity and STAT3 binding to a novel binding site of the PXN gene promoter. We also investigated the migration and invasive ability of nobiletin in ER+ cells. Nobiletin inhibited tumor angiogenesis by regulating Src, FAK, and STAT3 signaling through PXN in ER+ breast cancer cells.
Magnetic Hyperthermia and Oxidative Damage to DNA of Human Hepatocarcinoma Cells
Authors: Cellai Filippo , Munnia Armelle , Viti Jessica , Doumett Saer , Ravagli Costanza , Ceni Elisabetta , Mello Tommaso , Polvani Simone , Giese Roger , Baldi Giovanni , Galli Andrea , Peluso Marco
Published: May 2017

Nanotechnology is addressing major urgent needs for cancer treatment. We conducted a study to compare the frequency of 3-(2-deoxy-β-d-erythro-pentafuranosyl)pyrimido[1,2-α]purin-10(3H)-one deoxyguanosine (M1dG) and 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodG) adducts, biomarkers of oxidative stress and/or lipid peroxidation, on human hepatocarcinoma HepG2 cells exposed to increasing levels of Fe3O4-nanoparticles (NPs) versus untreated cells at different lengths of incubations, and in the presence of increasing exposures to an alternating magnetic field (AMF) of 186 kHz using 32P-postlabeling. The levels of oxidative damage tended to increase significantly after ≥24 h of incubations compared to controls. The oxidative DNA damage tended to reach a steady-state after treatment with 60 μg/mL of Fe3O4-NPs. Significant dose–response relationships were observed. A greater adduct production was observed after magnetic hyperthermia, with the highest amounts of oxidative lesions after 40 min exposure to AMF. The effects of magnetic hyperthermia were significantly increased with exposure and incubation times. Most important, the levels of oxidative lesions in AMF exposed NP treated cells were up to 20-fold greater relative to those observed in nonexposed NP treated cells. Generation of oxidative lesions may be a mechanism by which magnetic hyperthermia induces cancer cell death.
Unconventional Secretion of Heat Shock Proteins in Cancer
Authors: Santos Tiago Góss , Martins Vilma , Hajj Glaucia
Published: May 2017

Heat shock proteins (HSPs) are abundant cellular proteins involved with protein homeostasis. They have both constitutive and inducible isoforms, whose expression levels are further increased by stress conditions, such as temperature elevation, reduced oxygen levels, infection, inflammation and exposure to toxic substances. In these situations, HSPs exert a pivotal role in offering protection, preventing cell death and promoting cell recovery. Although the majority of HSPs functions are exerted in the cytoplasm and organelles, several lines of evidence reveal that HSPs are able to induce cell responses in the extracellular milieu. HSPs do not possess secretion signal peptides, and their secretion was subject to widespread skepticism until the demonstration of the role of unconventional secretion forms such as exosomes. Secretion of HSPs may confer immune system modulation and be a cell-to-cell mediated form of increasing stress resistance. Thus, there is a wide potential for secreted HSPs in resistance of cancer therapy and in the development new therapeutic strategies.
Clinical Correlates and Prognostic Value of Plasma Galectin-3 Levels in Degenerative Aortic Stenosis: A Single-Center Prospective Study of Patients Referred for Invasive Treatment
Authors: Bobrowska Beata , Wieczorek-Surdacka Ewa , Kruszelnicka Olga , Chyrchel Bernadeta , Surdacki Andrzej , Dudek Dariusz
Published: May 2017

Galectin-3 (Gal-3), a β-galactoside-binding lectin, has been implicated in myocardial fibrosis, development of left ventricular (LV) dysfunction and transition from compensated LV hypertrophy to overt heart failure (HF), being a novel prognostic marker in HF. Risk stratification is crucial for the choice of the optimal therapy in degenerative aortic stenosis (AS), affecting elderly subjects with coexistent diseases. Our aim was to assess correlates and prognostic value of circulating Gal-3 in real-world patients with degenerative AS referred for invasive treatment. Gal-3 levels were measured at admission in 80 consecutive patients with symptomatic degenerative AS (mean age: 79 ± 8 years; aortic valve area (AVA) index: 0.4 ± 0.1 cm2/m2). The therapeutic strategy was chosen following a dedicated multidisciplinary team-oriented approach, including surgical valve replacement (n = 11), transcatheter valve implantation (n = 19), balloon aortic valvuloplasty (BAV) (n = 25) and optimal medical therapy (n = 25). Besides routine echocardiographic indices, valvulo-arterial impedance (Zva), an index of global LV afterload, was computed. There were 22 deaths over a median follow-up of 523 days. Baseline Gal-3 correlated negatively with estimated glomerular filtration rate (eGFR) (r = −0.61, p < 0.001) and was unrelated to age, symptomatic status, AVA index, LV ejection fraction, LV mass index or Zva. For the study group as a whole, Gal-3 tended to predict mortality (Gal-3 >17.8 vs. Gal-3 <17.8 ng/mL; hazard ratio (HR): 2.03 (95% confidence interval, 0.88–4.69), p = 0.09), which was abolished upon adjustment for eGFR (HR: 1.70 (0.61–4.73), p = 0.3). However, in post-BAV patients multivariate-adjusted pre-procedural Gal-3 was associated with worse survival (HR: 7.41 (1.52–36.1), p = 0.01) regardless of eGFR. In conclusion, the inverse eGFR–Gal-3 relationship underlies a weak association between Gal-3 and adverse outcome in patients with degenerative AS referred for invasive therapy irrespective of type of treatment employed. In contrast, pre-procedural Gal-3 appears an independent mortality predictor in high-risk AS patients undergoing BAV.
Clinical Utility of the Adrenocorticotropin Stimulation Test with/without Dexamethasone Suppression for Definitive and Subtype Diagnosis of Primary Aldosteronism
Authors: Inoue Kosuke , Omura Masao , Sugisawa Chiho , Tsurutani Yuya , Saito Jun , Nishikawa Tetsuo
Published: May 2017

The adrenocorticotropin (ACTH) stimulation test (AST) has been reported to be useful for diagnosing primary aldosteronism (PA), particularly for differentiating PA subtypes under 1-mg dexamethasone suppression (DS). The aim of our study was to clarify the effect of 1-mg DS on AST results. A retrospective cohort study was conducted using data for 48 patients (PA: 30/48). We estimated the difference in plasma aldosterone concentration (PAC) responsiveness to ACTH stimulation with single (AST alone) and combined (AST under 1-mg DS) tests within the same patient. We compared the diagnostic accuracy of these two tests for PA and the laterality of hyperaldosteronism. We found no differences in PAC responsiveness to ACTH stimulation between single and combined tests, and observed a significant positive linear relationship (30 min, R2 = 0.75, p-value < 0.01). Both tests showed the highest diagnostic accuracy for PA following 30 min of ACTH stimulation. The ability to detect the laterality of hyperaldosteronism was inconsistent and differed according to the two definitions: lateralization ratio and the absolute aldosterone levels in adrenal venous sampling. PAC responsiveness to ACTH stimulation was similar for AST with and without 1-mg DS. AST can be performed under both conditions with similar accuracy to detect PA.
Hypoxia, HIF, and Associated Signaling Networks in Chronic Kidney Disease
Authors: Liu Jing , Wei Qingqing , Guo Chunyuan , Dong Guie , Liu Yu , Tang Chengyuan , Dong Zheng
Published: May 2017

The pathogenesis of chronic kidney disease (CKD) is complex and apparently multifactorial. Hypoxia or decrease in oxygen supply in kidney tissues has been implicated in CKD. Hypoxia inducible factors (HIF) are a small family of transcription factors that are mainly responsive to hypoxia and mediate hypoxic response. HIF plays a critical role in renal fibrosis during CKD through the modulation of gene transcription, crosstalk with multiple signaling pathways, epithelial-mesenchymal transition, and epigenetic regulation. Moreover, HIF also contributes to the development of various pathological conditions associated with CKD, such as anemia, inflammation, aberrant angiogenesis, and vascular calcification. Treatments targeting HIF and related signaling pathways for CKD therapy are being developed with promising clinical benefits, especially for anemia. This review presents an updated analysis of hypoxia response, HIF, and their associated signaling network involved in the pathogenesis of CKD.
Tubacin, an HDAC6 Selective Inhibitor, Reduces the Replication of the Japanese Encephalitis Virus via the Decrease of Viral RNA Synthesis
Authors: Lu Chien-Yi , Chang Yi-Chih , Hua Chun-Hung , Chuang Chieh , Huang Su-Hua , Kung Szu-Hao , Hour Mann-Jen , Lin Cheng-Wen
Published: May 2017

Japanese encephalitis virus (JEV), a neurotropic flavivirus, annually causes over 30,000 Japanese Encephalitis (JE) cases in East and Southeast Asia. Histone deacetylases (HDACs) modulate lysine acetylation of histones and non-histone proteins, regulating many processes including inflammation and antiviral immune response. This study investigated antiviral activity of pan- and selective-HDAC inhibitors as host-targeting agents against JEV. Among HDAC inhibitors, selective HDAC6 inhibitors (tubastatin-A (TBSA) and tubacin) concentration-dependently inhibited JEV-induced cytopathic effect and apoptosis, as well as reduced virus yield in human cerebellar medulloblastoma cells. The 50% inhibitory concentration (IC50) values of virus yield was 0.26 μM for tubacin and 1.75 μM for TBSA, respectively. Tubacin (IC50 of 1.52 μM), but not TBSA, meaningfully blocked the production of intracellular infectious virus particles. In time-of-addition assays, the greatest potency of antiviral activity was observed in the mode of pre-treatment with tubacin (IC50 of 1.89 μM) compared to simultaneous (IC50 of 4.88 μM) and post-treatment (IC50 of 2.05 μM) modes. Interestingly, tubacin induced the hyperacetylation of a HDAC6 substrate Hsp90 and reduced the interaction of Hsp90 with JEV NS5 protein. Novobiocin, an Hsp90 inhibitor, diminished the NS5 protein amount and virus replication in JEV-infected cells. Meantime, tubacin suppressed the NS5 expression and antisense RNA genome synthesis in infected cells. Tubacin-induced Hsp90 hyperacetylation was suggested to influence the NS5 activity in JEV replication. Therefore, tubacin had a high potential of a host-targeting agent against JEV, exhibiting preventive and therapeutic activities against JEV infection.
Comparative Proteomics of Rubber Latex Revealed Multiple Protein Species of REF/SRPP Family Respond Diversely to Ethylene Stimulation among Different Rubber Tree Clones
Authors: Tong Zheng , Wang Dan , Sun Yong , Yang Qian , Meng Xueru , Wang Limin , Feng Weiqiang , Li Ling , Wurtele Eve , Wang Xuchu
Published: May 2017

Rubber elongation factor (REF) and small rubber particle protein (SRPP) are two key factors for natural rubber biosynthesis. To further understand the roles of these proteins in rubber formation, six different genes for latex abundant REF or SRPP proteins, including REF138,175,258 and SRPP117,204,243, were characterized from Hevea brasiliensis Reyan (RY) 7-33-97. Sequence analysis showed that REFs have a variable and long N-terminal, whereas SRPPs have a variable and long C-terminal beyond the REF domain, and REF258 has a β subunit of ATPase in its N-terminal. Through two-dimensional electrophoresis (2-DE), each REF/SRPP protein was separated into multiple protein spots on 2-DE gels, indicating they have multiple protein species. The abundance of REF/SRPP proteins was compared between ethylene and control treatments or among rubber tree clones with different levels of latex productivity by analyzing 2-DE gels. The total abundance of each REF/SRPP protein decreased or changed a little upon ethylene stimulation, whereas the abundance of multiple protein species of the same REF/SRPP changed diversely. Among the three rubber tree clones, the abundance of the protein species also differed significantly. Especially, two protein species of REF175 or REF258 were ethylene-responsive only in the high latex productivity clone RY 8-79 instead of in RY 7-33-97 and PR 107. Some individual protein species were positively related to ethylene stimulation and latex productivity. These results suggested that the specific protein species could be more important than others for rubber production and post-translational modifications might play important roles in rubber biosynthesis.
Medial Patellofemoral Ligament Reconstruction in Adolescents Affected by Patellar Instability
Authors: Testa Gianluca , Pavone Vito , Lucenti Ludovico , Condorelli Giuseppe , Sessa Giuseppe
Published: May 2017

Patellar instability is a heterogeneous group of morphological and functional disorders of the knee extensor mechanism. The medial patellofemoral ligament (MPFL) has been recognized as being important in stabilizing the patella and preventing lateral patellar dislocation. Recurrent dislocations in the pediatric population may benefit from surgical intervention. The aim of this study is to retrospectively evaluate adolescent patients treated with surgical reconstruction of medial patello-femoral ligament. Between January 2009 and December 2014, seven patients with patellar instability were treated at the Department of Orthopaedics and Traumatology of the University of Catania, Sicily. Five patients (71.4%) were female and two (28.6%) were male. The mean age at the time of surgery was 14.9 ± 1.1 years (range 13–16 years). All cases were treated with reconstruction of the MPFL. Clinical outcomes and complications were reported. Mean follow-up was 26.1 ± 10.9 months (range 12–46 months). Evaluation at two years after surgery identified an average Knee Society Score (KSS) of 94.3 ± 7.4 (range 78–100). An excellent result was obtained in six patients (85.7%) and a good result was obtained in one patient (14.3%). A recurrence was reported in one patient (14.3%). This study shows that surgical treatment of patellar instability by reconstruction of MPFL leads to satisfying results at mid-term follow-up.
The Vibration of a Linear Carbon Chain in Carbon Nanotubes
Authors: Ding Dongqing , Zhao Yang , Dong Shuhong , Yu Peishi , Wang Liqiang , Zhao Junhua
Published: May 2017

An explicit solution for the vibration of a carbon chain inside carbon nanotubes (CNTs) was obtained using continuum modeling of the van der Waals (vdW) interactions between them. The effect of the initial tensile force and the amplitude of the carbon chain as well as the radii of the CNTs on the vibration frequency were analyzed in detail, respectively. Our analytical results show that the vibration frequency of the carbon chain in a (5,5) CNT could be around two orders of magnitude higher than that of an independent carbon chain without initial tensile force. For a given CNT radius, the vibration frequency nonlinearly increases with increasing amplitude and initial tensile force. The obtained analytical cohesive energy and vibration frequency are reasonable by comparison of present molecular dynamics (MD) simulations. These findings will be a great help towards understanding the vibration property of a nanowire in nanotubes, and designing nanoelectromechanical devices.
In-Depth Analysis of the Structure and Properties of Two Varieties of Natural Luffa Sponge Fibers
Authors: Chen Yuxia , Su Na , Zhang Kaiting , Zhu Shiliu , Zhao Lei , Fang Fei , Ren Linyan , Guo Yong
Published: May 2017

The advancement in science and technology has led to luffa sponge (LS) being widely used as a natural material in industrial application because of its polyporous structure and light texture. To enhance the utility of LS fibers as the reinforcement of lightweight composite materials, the current study investigates their water absorption, mechanical properties, anatomical characteristics and thermal performance. Hence, moisture regain and tensile properties of LS fiber bundles were measured in accordance with American Society for Testing and Materials (ASTM) standards while their structural characteristics were investigated via microscopic observation. Scanning electron microscopy (SEM) was used to observe the surface morphology and fractured surface of fiber bundles. The test results show that the special structure where the phloem tissues degenerate to cavities had a significant influence on the mechanical properties of LS fiber bundles. Additionally, the transverse sectional area occupied by fibers in a fiber bundle (SF), wall thickness, ratio of wall to lumen of fiber cell, and crystallinity of cellulose had substantial impact on the mechanical properties of LS fiber bundles. Furthermore, the density of fiber bundles of LS ranged within 385.46–468.70 kg/m3, significantly less than that of jute (1360.40 kg/m3) and Arenga engleri (950.20 kg/m3). However, LS fiber bundles demonstrated superior specific modulus than Arenga engleri.
Antibacterial Activity of Commercial Dentine Bonding Systems against E. faecalis–Flow Cytometry Study
Authors: Lukomska-Szymanska Monika , Konieczka Magdalena , Zarzycka Beata , Lapinska Barbara , Grzegorczyk Janina , Sokolowski Jerzy
Published: May 2017

Literature presents inconsistent results on the antibacterial activity of dentine bonding systems (DBS). Antibacterial activity of adhesive systems depends on several factors, including composition and acidity. Flow cytometry is a novel detection method to measure multiple characteristics of a single cell: total cell number, structural (size, shape), and functional parameters (viability, cell cycle). The LIVE/DEAD® BacLightTM bacterial viability assay was used to evaluate an antibacterial activity of DBS by assessing physical membrane disruption of bacteria mediated by DBS. Ten commercial DBSs: four total-etching (TE), four self-etching (SE) and two selective enamel etching (SEE) were tested. Both total-etching DBS ExciTE F and OptiBond Solo Plus showed comparatively low antibacterial activity against E. faecalis. The lowest activity of all tested TE systems showed Te-Econom Bond. Among SE DBS, G-ænial Bond (92.24% dead cells) followed by Clearfil S3 Bond Plus (88.02%) and Panavia F 2.0 ED Primer II (86.67%) showed the highest antibacterial activity against E. faecalis, which was comparable to isopropranol (positive control). In the present study, self-etching DBS exhibited higher antimicrobial activity than tested total-etching adhesives against E. faecalis.
Direct Growth of CuO Nanorods on Graphitic Carbon Nitride with Synergistic Effect on Thermal Decomposition of Ammonium Perchlorate
Authors: Tan Linghua , Xu Jianhua , Li Shiying , Li Dongnan , Dai Yuming , Kou Bo , Chen Yu
Published: May 2017

Novel graphitic carbon nitride/CuO (g-C3N4/CuO) nanocomposite was synthesized through a facile precipitation method. Due to the strong ion-dipole interaction between copper ions and nitrogen atoms of g-C3N4, CuO nanorods (length 200–300 nm, diameter 5–10 nm) were directly grown on g-C3N4, forming a g-C3N4/CuO nanocomposite, which was confirmed via X-ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), and X-ray photoelectron spectroscopy (XPS). Finally, thermal decomposition of ammonium perchlorate (AP) in the absence and presence of the prepared g-C3N4/CuO nanocomposite was examined by differential thermal analysis (DTA), and thermal gravimetric analysis (TGA). The g-C3N4/CuO nanocomposite showed promising catalytic effects for the thermal decomposition of AP. Upon addition of 2 wt % nanocomposite with the best catalytic performance (g-C3N4/20 wt % CuO), the decomposition temperature of AP was decreased by up to 105.5 °C and only one decomposition step was found instead of the two steps commonly reported in other examples, demonstrating the synergistic catalytic activity of the as-synthesized nanocomposite. This study demonstrated a successful example regarding the direct growth of metal oxide on g-C3N4 by ion-dipole interaction between metallic ions, and the lone pair electrons on nitrogen atoms, which could provide a novel strategy for the preparation of g-C3N4-based nanocomposite.
Origin of the El Dragón Selenium Mineralization, Quijarro Province, Potosí, Bolivia
Authors: Grundmann Günter , Förster Hans-Jürgen
Published: May 2017

A re-examination of the El Dragón vein-type Se deposit using polarized light microscopy and scanning-electron microscopy combined with electron-microprobe analyses revealed the following results: the detection of (a) petříčekite, krut’aite and penroseite close to endmember composition; (b) a yet unknown mineral of the ideal composition CuNi2Se4; (c) intermediate members of the vaesite-pyrite solid-solution series; and (d) a mineral with a composition intermediate between athabascaite and its yet unknown S-equivalent, Cu4S5. Triggered by volcanic-hydrothermal activities around the Porco caldera, formation of the mineralization involved five episodes of fault formation and re-opening, fluid-mediated metal mobilization, metalliferous fluid infiltration, and mineral precipitation, re-deposition, and alteration that probably extended from 12 Ma until today. The origin of the Se-vein was accomplished by the multiple injection of highly oxidized, metal-rich fluids into a fault at the interface between black shale and siltstone. These low-T solutions (estimated max. temperature 100 °C, max. pressure 1 bar) possessed high to exceptionally Se fugacities (log fSe2 fluctuating between of −14.5 and −11.2) that prevailed for most of the evolution of the deposit, only interrupted once, during the episode of deposition of sulfides of Cu and Fe and resulting partial alteration of the pre-existing selenides. Formation of end-member krut’aite and native selenium implies a minimum log fSe2 of −11.2 at the final stage of vein formation. The likely source of Se and the accompanying metals (Cu, Ag, Ni, Co, Au, Pb, Hg, Cd, Fe and Bi) is the neighboring Kupferschiefer-type (possibly Devonian) black shale rich in framboidal pyrite, Cu-sulfide aggregates, and organic matter. Deposition of Se-minerals occurred where the oxidized metal-bearing solutions became in contact with a reductant, associated with the reduction of mobile selenate to immobile selenide or elemental Se.
Silver Nanoparticles Mediated by Costus afer Leaf Extract: Synthesis, Antibacterial, Antioxidant and Electrochemical Properties
Authors: Elemike Elias , Fayemi Omolola , Ekennia Anthony , Onwudiwe Damian , Ebenso Eno
Published: May 2017

Synthesis of metallic and semiconductor nanoparticles through physical and chemical routes has been extensively reported. However, green synthesized metal nanoparticles are currently in the limelight due to the simplicity, cost-effectiveness and eco-friendliness of their synthesis. This study explored the use of aqueous leaf extract of Costus afer in the synthesis of silver nanoparticles (CA-AgNPs). The optical and structural properties of the resulting silver nanoparticles were studied using UV-visible spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Fourier transform infra–red spectrophotometer (FTIR). TEM images of the silver nanoparticles confirmed the existence of monodispersed spherical nanoparticles with a mean size of 20 nm. The FTIR spectra affirmed the presence of phytochemicals from the Costus afer leaf extract on the surface of the silver nanoparticles. The electrochemical characterization of a CA-AgNPs/multiwalled carbon nanotubes (MWCNT)-modified electrode was carried out to confirm the charge transfer properties of the nanocomposites. The comparative study showed that the CA-AgNPs/MWCNT-modified electrode demonstrated faster charge transport behaviour. The anodic current density of the electrodes in Fe(CN)6]4−/[Fe(CN)6]3− redox probe follows the order: GCE/CA-Ag/MWCNT (550 mA/cm2) > GCE/MWCNT (270 mA/cm2) > GCE (80 mA/cm2) > GCE/CA-Ag (7.93 mA/cm2). The silver nanoparticles were evaluated for their antibacterial properties against Gram negative (Escherichia coli, Klebsiella pneumonia, Pseudomonas aeruginosa) and Gram positive (Bacillus subtilis and Staphylococcus aureus) pathogens. The nanoparticles exhibited better inhibition of the bacterial strains compared to the precursors (leaf extract of Costus afer and silver nitrate). Furthermore, the ability of the nanoparticles to scavenge DPPH radicals at different concentrations was studied using the DPPH radical scavenging assay and compared to that of the leaf extract and ascorbic acid. The nanoparticles were better DPPH scavengers compared to the leaf extract and their antioxidant properties compared favorably the antioxidant results of ascorbic acid. The green approach to nanoparticles synthesis carried out in this research work is simple, non-polluting, inexpensive and non-hazardous.
Oleuropein and Cancer Chemoprevention: The Link is Hot
Authors: Ahmad Farooqi Ammad , Fayyaz Sundas , Silva Ana , Sureda Antoni , Nabavi Seyed , Mocan Andrei , Nabavi Seyed , Bishayee Anupam
Published: May 2017

Cancer comprises a collection of related diseases characterized by the existence of altered cellular pathways resulting in an abnormal tendency for uncontrolled growth. A broad spectrum, coordinated, and personalized approach focused on targeting diverse oncogenic pathways with low toxicity and economic natural compounds can provide a real benefit as a chemopreventive and/or treatment of this complex disease. Oleuropein, a bioactive phenolic compound mainly present in olive oil and other natural sources, has been reported to modulate several oncogenic signalling pathways. This review presents and critically discusses the available literature about the anticancer and onco-suppressive activity of oleuropein and the underlying molecular mechanisms implicated in the anticarcinogenic and therapeutic effects. The existence of limitations and the promising perspectives of research on this phenolic compound are also critically analyzed and discussed.
Sampling Terrestrial Environments for Bacterial Polyketides
Authors: Hill Patrick , Heberlig Graham , Boddy Christopher
Published: May 2017

Bacterial polyketides are highly biologically active molecules that are frequently used as drugs, particularly as antibiotics and anticancer agents, thus the discovery of new polyketides is of major interest. Since the 1980s discovery of polyketides has slowed dramatically due in large part to the repeated rediscovery of known compounds. While recent scientific and technical advances have improved our ability to discover new polyketides, one key area has been under addressed, namely the distribution of polyketide-producing bacteria in the environment. Identifying environments where producing bacteria are abundant and diverse should improve our ability to discover (bioprospect) new polyketides. This review summarizes for the bioprospector the state-of-the-field in terrestrial microbial ecology. It provides insight into the scientific and technical challenges limiting the application of microbial ecology discoveries for bioprospecting and summarizes key developments in the field that will enable more effective bioprospecting. The major recent efforts by researchers to sample new environments for polyketide discovery is also reviewed and key emerging environments such as insect associated bacteria, desert soils, disease suppressive soils, and caves are highlighted. Finally strategies for taking and characterizing terrestrial samples to help maximize discovery efforts are proposed and the inclusion of non-actinomycetal bacteria in any terrestrial discovery strategy is recommended.
Volatile Composition in Two Pummelo Cultivars (Citrus grandis L. Osbeck) from Different Cultivation Regions in China
Authors: Zhang Mingxia , Li Linbo , Wu Zhongwei , Wang Yanjie , Zang Yiming , Liu Guojie
Published: May 2017

This study investigated the composition of volatile compounds in two pummelo cultivars, including ‘Shatian’ and ‘Guanxi’, cultivated in different regions of China with the aim of studying the effect of cultivar and cultivation condition on biosynthesis of volatile compounds in pummelo. Volatile compounds were extracted from pummelo juice using head-space microextraction and then analyzed using gas chromatography coupled with mass spectrometry. Results showed that a total of 49 volatile compounds was detected in the study, including 11 aldehydes, 7 alcohols, 3 ketones, 7 esters, 19 terpenes and 2 other volatiles. The ‘Guanxi’ pummelo cultivar possessed a more complex composition of volatile compounds compared with the ‘Shatian’ cultivar. Meanwhile, the volatile compounds appeared to exhibit a higher concentration in the ‘Guanxi’ cultivar samples than the ‘Shatian’ cultivar. Cluster analysis revealed that the ‘Guanxi’ cultivar samples from the different regions were grouped together, whereas the ‘Shatian’ cultivar samples were assembled. Principal component analysis showed that an obvious separation was observed between the ‘Guanxi’ and ‘Shatian’ cultivar. However, the ‘Shatian-SC15’ was significantly separated from the other ‘Shatian’ cultivar samples. These indicated that cultivar genotype was the primary factor that determined the volatile profile of the pummelo cultivar. Cultivation region might affect the biosynthesis of volatile compounds, resulting in the differentiation of the volatile composition in each pummelo cultivar.
Calcination Method Synthesis of SnO2/g-C3N4 Composites for a High-Performance Ethanol Gas Sensing Application
Authors: Cao Jianliang , Qin Cong , Wang Yan , Zhang Bo , Gong Yuxiao , Zhang Huoli , Sun Guang , Bala Hari , Zhang Zhanying
Published: May 2017

The SnO2/g-C3N4 composites were synthesized via a facile calcination method by using SnCl4·5H2O and urea as the precursor. The structure and morphology of the as-synthesized composites were characterized by the techniques of X-ray diffraction (XRD), the field-emission scanning electron microscopy and transmission electron microscopy (FESEM and TEM), energy dispersive spectrometry (EDS), thermal gravity and differential thermal analysis (TG-DTA), and N2-sorption. The analysis results indicated that the as-synthesized samples possess the two dimensional structure. Additionally, the SnO2 nanoparticles were highly dispersed on the surface of the g-C3N4 nanosheets. The gas-sensing performance of the as-synthesized composites for different gases was tested. Moreover, the composite with 7 wt % g-C3N4 content (SnO2/g-C3N4-7) exhibits an admirable gas-sensing property to ethanol, which possesses a higher response and better selectivity than that of the pure SnO2-based sensor. The high surface area of the SnO2/g-C3N4 composite and the good electronic characteristics of the two dimensional graphitic carbon nitride are in favor of the elevated gas-sensing property.
Improvement of Antioxidant Defences and Mood Status by Oral GABA Tea Administration in a Mouse Model of Post-Stroke Depression
Authors: Daglia Maria , Di Lorenzo Arianna , Nabavi Seyed Fazel , Sureda Antoni , Khanjani Sedigheh , Moghaddam Akbar Hajizadeh , Braidy Nady , Nabavi Seyed Mohammad
Published: May 2017

Green GABA (GGABA) and Oolong GABA (OGABA) teas are relatively new varieties of tea, whose chemical composition and functional properties are largely under-studied, despite their promising health capacities. Post stroke depression (PSD) is a complication of stroke with high clinical relevance, yielding increasing mortality and morbidity rates, and a lower response to common therapies and rehabilitation. Methods: Two chemically characterized commercial samples of GGABA and OGABA were investigated for effects on mood following oral administration using a mouse model of PSD, through common validated tests including the Despair Swimming Test and Tail Suspension Test. Moreover, the antioxidant activity of GGABA and OGABA was evaluated by determining the levels of lipid peroxidation products and the activity of antioxidant enzymes in the mouse brain in vivo. Results: GGABA and OGABA attenuated depressed mood by influencing behavioral parameters linked to depression. GGABA was more active than OGABA in this study, and this effect may be likely due to a higher content of polyphenolic substances and amino acids in GGABA compared to OGABA. GGABA also exerted a greater antioxidant activity. Conclusions: Our data suggests that GABA tea is a promising candidate that can be used as an adjuvant in the management of PSD.
The Impact of Exclusive Enteral Nutrition (EEN) on the Gut Microbiome in Crohn’s Disease: A Review
Authors: MacLellan Amber , Connors Jessica , Grant Shannan , Cahill Leah , Langille Morgan , Van Limbergen Johan
Published: May 2017

Crohn’s disease (CD), a form of inflammatory bowel disease (IBD), is thought to arise from a complex interaction of genetics, the gut microbiome, and environmental factors, such as diet. There is clear evidence that dietary intervention is successful in the treatment of CD—exclusive enteral nutrition (EEN) is able to induce remission in up to 80% of CD patients. While the mechanism of action of EEN is not clear, EEN is known to cause profound changes in the gut microbiome. Understanding how EEN modifies the gut microbiome to induce remission could provide insight into CD etiopathogenesis and aid the development of microbiome-targeted interventions to guide ongoing dietary therapy to sustain remission. This review includes current literature on changes in composition and function of the gut microbiome associated with EEN treatment in CD patients.
Mapping Reflectance Anisotropy of a Potato Canopy Using Aerial Images Acquired with an Unmanned Aerial Vehicle
Authors: Roosjen Peter , Suomalainen Juha , Bartholomeus Harm , Kooistra Lammert , Clevers Jan
Published: May 2017

Viewing and illumination geometry has a strong influence on optical measurements of natural surfaces due to their anisotropic reflectance properties. Typically, cameras on-board unmanned aerial vehicles (UAVs) are affected by this because of their relatively large field of view (FOV) and thus large range of viewing angles. In this study, we investigated the magnitude of reflectance anisotropy effects in the 500–900 nm range, captured by a frame camera mounted on a UAV during a standard mapping flight. After orthorectification and georeferencing of the images collected by the camera, we calculated the viewing geometry of all observations of each georeferenced ground pixel, forming a dataset with multi-angular observations. We performed UAV flights on two days during the summer of 2016 over an experimental potato field where different zones in the field received different nitrogen fertilization treatments. These fertilization levels caused variation in potato plant growth and thereby differences in structural properties such as leaf area index (LAI) and canopy cover. We fitted the Rahman–Pinty–Verstraete (RPV) model through the multi-angular observations of each ground pixel to quantify, interpret, and visualize the anisotropy patterns in our study area. The Θ parameter of the RPV model, which controls the proportion of forward and backward scattering, showed strong correlation with canopy cover, where in general an increase in canopy cover resulted in a reduction of backward scattering intensity, indicating that reflectance anisotropy contains information on canopy structure. In this paper, we demonstrated that anisotropy data can be extracted from measurements using a frame camera, collected during a typical UAV mapping flight. Future research will focus on how to use the anisotropy signal as a source of information for estimation of physical vegetation properties.
3D Digitisation of Large-Scale Unstructured Great Wall Heritage Sites by a Small Unmanned Helicopter
Authors: Deng Fucheng , Zhu Xiaorui , Li Xiaochun , Li Meng
Published: May 2017

The ancient Great Wall of China has long suffered from damage due to natural factors and human activities. A small low-cost unmanned helicopter system with a laser scanner and a digital camera is developed to efficiently visualize the status of the huge Great Wall area. The goal of the system is to achieve 3D digitisation of the large-scale Great Wall using a combination of fly-hover-scan and flying-scan modes. However, pose uncertainties of the unmanned helicopter could cause mismatching among point clouds acquired by each hovering-scan. This problem would become more severe as the target area becomes larger and more unstructured. Therefore, a hierarchical optimization framework is proposed in this paper to achieve 3D digitisation of the large-scale unstructured Great Wall with unpredictable pose uncertainties of the unmanned helicopter. In this framework, different optimization methodologies are proposed for the fly-hover-scan and flying-scan modes, respectively, because different scan modes would result in different features of point clouds. Moreover, a user-friendly interface based on WebGL has been developed for 3D model visualization and comparison. Experimental results demonstrate the feasibility of the proposed framework for 3D digitisation of the Great Wall segments.
Observational Quantification of Climatic and Human Influences on Vegetation Greening in China
Authors: Hua Wenjian , Chen Haishan , Zhou Liming , Xie Zhenghui , Qin Minhua , Li Xing , Ma Hedi , Huang Qinghan , Sun Shanlei
Published: May 2017

This study attempts to quantify the relative contributions of vegetation greening in China due to climatic and human influences from multiple observational datasets. Satellite measured vegetation greenness, Normalized Difference Vegetation Index (NDVI), and relevant climate, land cover, and socioeconomic data since 1982 are analyzed using a multiple linear regression (MLR) method. A statistically significant positive trend of average growing-season (April–October) NDVI is found over more than 34% of the vegetated areas, mainly in North China, while significant decreases in NDVI are only seen in less than 5% of the areas. The relationships between vegetation and climate (temperature, precipitation, and radiation) vary by geographical location and vegetation type. We estimate the NDVI changes in association with the non-climatic effects by removing the climatic effects from the original NDVI time series using the MLR analysis. Our results indicate that land use change is the dominant factor driving the long-term changes in vegetation greenness. The significant greening in North China is due to the increase in crops, grasslands, and forests. The socioeconomic datasets provide consistent and supportive results for the non-climatic effects at the provincial level that afforestation and reduced fire events generally have a major contribution. This study provides a basis for quantifying the non-climatic effects due to possible human influences on the vegetation greening in China.
A Novel Classification Technique of Landsat-8 OLI Image-Based Data Visualization: The Application of Andrews’ Plots and Fuzzy Evidential Reasoning
Authors: Boonprong Sornkitja , Cao Chunxiang , Torteeka Peerapong , Chen Wei
Published: May 2017

Andrews first proposed an equation to visualize the structures within data in 1972. Since then, this equation has been used for data transformation and visualization in a wide variety of fields. However, it has yet to be applied to satellite image data. The effect of unwanted, or impure, pixels occurring in these data varies with their distribution in the image; the effect is greater if impurity pixels are included in a classifier’s training set. Andrews’ curves enable the interpreter to select outlier or impurity data that can be grouped into a new category for classification. This study overcomes the above-mentioned problem and illustrates the novelty of applying Andrews’ plots to satellite image data, and proposes a robust method for classifying the plots that combines Dempster-Shafer theory with fuzzy set theory. In addition, we present an example, obtained from real satellite images, to demonstrate the application of the proposed classification method. The accuracy and robustness of the proposed method are investigated for different training set sizes and crop types, and are compared with the results of two traditional classification methods. We find that outlier data are easily eliminated by examining Andrews’ curves and that the proposed method significantly outperforms traditional methods when considering the classification accuracy.
An Assessment of Satellite-Derived Rainfall Products Relative to Ground Observations over East Africa
Authors: Kimani Margaret , Hoedjes Joost , Su Zhongbo
Published: May 2017

Accurate and consistent rainfall observations are vital for climatological studies in support of better agricultural and water management decision-making and planning. In East Africa, accurate rainfall estimation with an adequate spatial distribution is limited due to sparse rain gauge networks. Satellite rainfall products can potentially play a role in increasing the spatial coverage of rainfall estimates; however, their performance needs to be understood across space–time scales and factors relating to their errors. This study assesses the performance of seven satellite products: Tropical Applications of Meteorology using Satellite and ground-based observations (TAMSAT), African Rainfall Climatology And Time series (TARCAT), Climate Hazards Group InfraRed Precipitation with Station data (CHIRPS), Tropical Rainfall Measuring Mission (TRMM-3B43), Climate Prediction Centre (CPC) Morphing technique (CMORPH), Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks Climate Data Record (PERSIANN-CDR), CPC Merged Analysis of Precipitation (CMAP), and Global Precipitation Climatology Project (GPCP), using locally developed gridded (0.05°) rainfall data for 15 years (1998–2012) over East Africa. The products’ assessments were done at monthly and yearly timescales and were remapped to the gridded rain gauge data spatial scale during the March to May (MAM) and October to December (OND) rainy seasons. A grid-based statistical comparison between the two datasets was used, but only pixel values located at the rainfall stations were considered for validation. Additionally, the impact of topography on the performance of the products was assessed by analyzing the pixels in areas of highest negative bias. All the products could substantially replicate rainfall patterns, but their differences are mainly based on retrieving high rainfall amounts, especially of localized orographic types. The products exhibited systematic errors, which decreased with an increase in temporal resolution from a monthly to yearly scale. Challenges in retrieving orographic rainfall, especially during the OND season, were identified as the main cause of high underestimations. Underestimation was observed when elevation was <2500 m and above this threshold; overestimation was evident in mountainous areas. CMORPH, CHIRPS, and TRMM showed consistently high performance during both seasons, and this was attributed to their ability to retrieve rainfall of different rainfall regimes.