bluuebunny/crossref_metadata_2025 huggingface dataset:
The Anti-Inflammatory Role of Mannich Curcuminoids; Special Focus on Colitis
Authors: Szebeni Gábor J. , Nagy Lajos I. , Berkó Anikó , Hoffmann Alexandra , Fehér Liliána Z. , Bagyánszki Mária , Kari Beáta , Balog József A. , Hackler László , Kanizsai Iván , Pósa Anikó , Varga Csaba , Puskás László G.
Published: April 2019

The incidence of inflammatory bowel disease (IBD) increases gradually in Western countries with high need for novel therapeutic interventions. Mannich curcuminoids, C142 or C150 synthetized in our laboratory, have been tested for anti-inflammatory activity in a rat model of TNBS (2,4,6-trinitrobenzenesulphonic acid) induced colitis. Treatment with C142 or C150 reduced leukocyte infiltration to the submucosa and muscular propria of the inflamed gut. C142 or C150 rescued the loss of body weight and C150 decreased the weight of standard colon preparations proportional with 20% less tissue oedema. Both C142 and C150 curcumin analogues caused 25% decrease in the severity of colonic inflammation and haemorrhagic lesion size. Colonic MPO (myeloperoxidase) enzyme activity as an indicator of intense neutrophil infiltration was 50% decreased either by C142 or C150 Mannich curcuminoids. Lipopolysaccharide (LPS) co-treatment with Mannich curcuminoids inhibited NF-κB (nuclear factor kappa B) activity on a concentration-dependent manner in an NF-κB-driven luciferase expressing reporter cell line. Co-treatment with LPS and curcuminoids, C142 or C150, resulted in NF-κB inhibition with 3.57 μM or 1.6 μM half maximal effective concentration (EC50) values, respectively. C150 exerted a profound inhibition of the expression of inflammatory cytokines, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-4 (IL-4) in human PBMCs (peripheral blood mononuclear cells) upon LPS stimulus. Mannich curcuminoids reported herein possess a powerful anti-inflammatory activity.
Diamond Nanoparticles Downregulate Expression of CycD and CycE in Glioma Cells
Authors: Grodzik Marta , Szczepaniak Jaroslaw , Strojny-Cieslak Barbara , Hotowy Anna , Wierzbicki Mateusz , Jaworski Slawomir , Kutwin Marta , Soltan Emilia , Mandat Tomasz , Lewicka Aneta , Chwalibog Andre
Published: April 2019

Our previous studies have shown that diamond nanoparticles (NDs) exhibited antiangiogenic and proapoptotic properties in vitro in glioblastoma multiforme (GBM) cells and in tumors in vivo. Moreover, NDs inhibited adhesion, leading to the suppression of migration and invasion of GBM. In the present study, we hypothesized that the NDs might also inhibit proliferation and cell cycle in glioma cells. Experiments were performed in vitro with the U87 and U118 lines of GBM cells, and for comparison, the Hs5 line of stromal cells (normal cells) after 24 h and 72 h of treatment. The analyses included cell morphology, cell death, viability, and cell cycle analysis, double timing assay, and gene expression (Rb, E2F1, CycA, CycB, CycD, CycE, PTEN, Ki-67). After 72 h of ND treatment, the expression level of Rb, CycD, and CycE in the U118 cells, and E2F1, CycD, and CycE in the U87 cells were significantly lower in comparison to those in the control group. We observed that decreased expression of cyclins inhibited the G1/S phase transition, arresting the cell cycle in the G0/G1 phase in glioma cells. The NDs did not affect the cell cycle as well as PTEN and Ki-67 expression in normal cells (Hs5), although it can be assumed that the NDs reduced proliferation and altered the cell cycle in fast dividing cells.
Synthesis and In Vitro Antibacterial Activity of Quaternized 10-Methoxycanthin-6-one Derivatives
Authors: Li Na , Liu Dan , Dai Jiang-Kun , Wang Jin-Yi , Wang Jun-Ru
Published: April 2019

Background: Based on our previous work, we found that 10-methoxycanthin-6-one displayed potential antibacterial activity and quaternization was an available method for increasing the antibacterial activity. Here, we explored the antibacterial activity of quaternized 10-methoxy canthin-6-one derivatives. Methods and Results: Twenty-two new 3-N-benzylated 10-methoxy canthin-6-ones were designed and synthesized through quaternization reaction. The in vitro antibacterial activity against three bacteria was evaluated by the double dilution method. Moreover, the structure–activity relationships (SARs) were carefully summarized in order to guide the development of antibacterial canthin-6-one agents. Two highly active compounds (6p and 6t) displayed 8-fold superiority (MIC = 3.91 µg/mL) against agricultural pathogenic bacteria R. solanacearum and P. syringae compared to agrochemical streptomycin sulfate, and showed potential activity against B. cereus. Moreover, these two compounds exhibited good “drug-like” properties, low cytotoxicity, and no inhibition on seed germination. Conclusions: This work provides two new effective quaternized canthin-6-one derivatives as candidate bactericide, promoting the development of natural-sourced bactericides and preservatives.
Extraction, Purification, Structural Characteristics, Biological Activities and Pharmacological Applications of Acemannan, a Polysaccharide from Aloe vera: A Review
Authors: Liu Chang , Cui Yan , Pi Fuwei , Cheng Yuliang , Guo Yahui , Qian He
Published: April 2019

Aloe vera is a medicinal plant species of the genus Aloe with a long history of usage around the world. Acemannan, considered one of the main bioactive polysaccharides of Aloe vera, possesses immunoregulation, anti-cancer, anti-oxidation, wound healing and bone proliferation promotion, neuroprotection, and intestinal health promotion activities, among others. In this review, recent advancements in the extraction, purification, structural characteristics and biological activities of acemannan from Aloe vera were summarized. Among these advancements, the structural characteristics of purified polysaccharides were reviewed in detail. Meanwhile, the biological activities of acemannan from Aloe vera determined by in vivo, in vitro and clinical experiments are summarized, and possible mechanisms of these bioactivities were discussed. Moreover, the latest research progress on the use of acemannan in dentistry and wound healing was also summarized in details. The structure-activity relationships of acemannan and its medical applications were discussed. Finally, new perspectives for future research work on acemannan were proposed. In conclusion, this review summarizes the extraction, purification, structural characteristics, biological activities and pharmacological applications of acemannan, and provides information for the industrial production and possible applications in dentistry and wound healing in the future.
Using Extra Virgin Olive Oil to Cook Vegetables Enhances Polyphenol and Carotenoid Extractability: A Study Applying the sofrito Technique
Authors: Rinaldi de Alvarenga José Fernando , Quifer-Rada Paola , Francetto Juliano Fernanda , Hurtado-Barroso Sara , Illan Montserrat , Torrado-Prat Xavier , Lamuela-Raventós Rosa Maria
Published: April 2019

Olive oil is the main source of fat in the Mediterranean diet and the most frequently used ingredient in Mediterranean cuisine. Cooking with olive oil has been attracting attention because it can act as a food excipient, thereby increasing the bioaccessibility and bioavailability of ingested bioactive compounds. The aim of this study was to understand the effect of cooking with olive oil on the bioactive components in other ingredients (tomato, onion, and garlic) of sofrito sauce, a representative model of Mediterranean cuisine. After the cooking process, polyphenols from tomato, onion, and garlic were detected in the olive oil, especially naringenin, ferulic acid, and quercetin, as well as a high content of carotenoid Z-isomers, which are more bioavailable than the E-isomers. Therefore, traditional Mediterranean cuisine could play an important role in the health-improving effects of the Mediterranean diet.
Studies Towards Hypoxia-Activated Prodrugs of PARP Inhibitors
Authors: Dickson Benjamin D. , Wong Way Wua , Wilson William R. , Hay Michael P.
Published: April 2019

Poly(ADP-ribose)polymerase (PARP) inhibitors (PARPi) have recently been approved for the treatment of breast and ovarian tumors with defects in homologous recombination repair (HRR). Although it has been demonstrated that PARPi also sensitize HRR competent tumors to cytotoxic chemotherapies or radiotherapy, normal cell toxicity has remained an obstacle to their use in this context. Hypoxia-activated prodrugs (HAPs) provide a means to limit exposure of normal cells to active drug, thus adding a layer of tumor selectivity. We have investigated potential HAPs of model PARPi in which we attach a bioreducible “trigger” to the amide nitrogen, thereby blocking key binding interactions. A representative example showed promise in abrogating PARPi enzymatic activity in a biochemical assay, with a ca. 160-fold higher potency of benzyl phthalazinone 4 than the corresponding model HAP 5, but these N-alkylated compounds did not release the PARPi upon one-electron reduction by radiolysis. Therefore, we extended our investigation to include NU1025, a PARPi that contains a phenol distal to the core binding motif. The resulting 2-nitroimidazolyl ether provided modest abrogation of PARPi activity with a ca. seven-fold decrease in potency, but released the PARPi efficiently upon reduction. This investigation of potential prodrug approaches for PARPi has identified a useful prodrug strategy for future exploration.
DNA Damaging Effects, Oxidative Stress Responses and Cholinesterase Activity in Blood and Brain of Wistar Rats Exposed to Δ9-Tetrahydrocannabinol
Authors: Kopjar Nevenka , Fuchs Nino , Žunec Suzana , Mikolić Anja , Micek Vedran , Kozina Goran , Lucić Vrdoljak Ana , Brčić Karačonji Irena
Published: April 2019

Currently we are faced with an ever-growing use of Δ9-tetrahydrocannabinol (THC) preparations, often used as supportive therapies for various malignancies and neurological disorders. As some of illegally distributed forms of such preparations, like cannabis oils and butane hash oil, might contain over 80% of THC, their consumers can become intoxicated or experience various detrimental effects. This fact motivated us for the assessments of THC toxicity in vivo on a Wistar rat model, at a daily oral dose of 7 mg/kg which is comparable to those found in illicit preparations. The main objective of the present study was to establish the magnitude and dynamics of DNA breakage associated with THC exposure in white blood and brain cells of treated rats using the alkaline comet assay. The extent of oxidative stress after acute 24 h exposure to THC was also determined as well as changes in activities of plasma and brain cholinesterases (ChE) in THC-treated and control rats. The DNA of brain cells was more prone to breakage after THC treatment compared to DNA in white blood cells. Even though DNA damage quantified by the alkaline comet assay is subject to repair, its elevated level detected in the brain cells of THC-treated rats was reason for concern. Since neurons do not proliferate, increased levels of DNA damage present threats to these cells in terms of both viability and genome stability, while inefficient DNA repair might lead to their progressive loss. The present study contributes to existing knowledge with evidence that acute exposure to a high THC dose led to low-level DNA damage in white blood cells and brain cells of rats and induced oxidative stress in brain, but did not disturb ChE activities.
Beer Molecules and Its Sensory and Biological Properties: A Review
Authors: Humia Bruno Vieira , Santos Klebson Silva , Barbosa Andriele Mendonça , Sawata Monize , Mendonça Marcelo da Costa , Padilha Francine Ferreira
Published: April 2019

The production and consumption of beer plays a significant role in the social, political, and economic activities of many societies. During brewing fermentation step, many volatile and phenolic compounds are produced. They bring several organoleptic characteristics to beer and also provide an identity for regional producers. In this review, the beer compounds synthesis, and their role in the chemical and sensory properties of craft beers, and potential health benefits are described. This review also describes the importance of fermentation for the brewing process, since alcohol and many volatile esters are produced and metabolized in this step, thus requiring strict control. Phenolic compounds are also present in beer and are important for human health since it was proved that many of them have antitumor and antioxidant activities, which provides valuable data for moderate dietary beer inclusion studies.
Copper-Catalyzed Regioselective Synthesis of (E)-β-Fluorovinyl Sulfones
Authors: Román Raquel , Barrio Pablo , Mateu Natalia , Sedgwick Daniel M. , Fustero Santos
Published: April 2019

Organofluorine compounds are finding increasing application in a variety of fields such as pharmaceutical, agrochemical, and material sciences. However, given the scarcity of fluorine-containing natural products, advancement in this area depends almost entirely on the development of new synthetic methodologies. In this article, we present the synthesis of a series of previously undescribed (E)-β-fluorovinyl sulfones via a simple copper-catalyzed addition of hydrogen fluoride to alkynyl sulfone starting materials in varying yields and E/Z selectivities. The hydrogenation of these products was also explored and compared with the hydrogenation of the related Z isomers. These new products may find interesting applications, given the versatility of vinyl sulfones in chemical synthesis and the unique properties of vinyl fluorides in biological settings.
An Investigation on Glucuronidation Metabolite Identification, Isozyme Contribution, and Species Differences of GL-V9 In Vitro and In Vivo
Authors: Xing Han , Kong Dexuan , Ning Chen , Kong Ying , Ren Chang , Cheng Yujie , Cai Hui , Wang Jubo , Zhao Di , Li Ning , Chen Xijing , Li Zhiyu , Lu Yang
Published: April 2019

GL-V9 is a prominent derivative of wogonin with a wide therapeutic spectrum and potent anti-tumor activity. The metabolism characteristics of GL-V9 remain unclear. This study aimed to clarify the metabolic pathway of GL-V9 and investigate the generation of its glucuronidation metabolites in vitro and in vivo. HPLC-UV-TripleTOF was used to identify metabolites. The main metabolite that we found was chemically synthesized and the synthetic metabolite was utilized as standard substance for the subsequent metabolism studies of GL-V9, including enzyme kinetics in liver microsomes of five different species and reaction phenotyping metabolism using 12 recombinant human UDP-glucuronosyltransferase (UGT) isoforms. Results indicated that the glucuronidation reaction occurred at C5-OH group, and 5-O-glucuronide GL-V9 is the only glucuronide metabolite and major phase II metabolite of GL-V9. Among 12 recombinant human UGTs, rUGT1A9 showed the strongest catalytic capacity for the glucuronidation reaction of GL-V9. rUGT1A7 and rUGT1A8 were also involved in the glucuronidation metabolism. Km of rUGT1A7-1A9 was 3.25 ± 0.29, 13.92 ± 1.05, and 4.72 ± 0.28 μM, respectively. In conclusion, 5-O-glucuronide GL-V9 is the dominant phase II metabolite of GL-V9 in vivo and in vitro, whose formation rate and efficiency are closely related to isoform-specific metabolism profiles and the distribution of UGTs in different tissues of different species.
Identification and Functional Analysis of a Flavonol Synthase Gene from Grape Hyacinth
Authors: Liu Hongli , Su Beibei , Zhang Han , Gong Jiaxin , Zhang Boxiao , Liu Yali , Du Lingjuan
Published: April 2019

Flavonols are important copigments that affect flower petal coloration. Flavonol synthase (FLS) catalyzes the conversion of dihydroflavonols to flavonols. In this study, we identified a FLS gene, MaFLS, expressed in petals of the ornamental monocot Muscari aucheri (grape hyacinth) and analyzed its spatial and temporal expression patterns. qRT-PCR analysis showed that MaFLS was predominantly expressed in the early stages of flower development. We next analyzed the in planta functions of MaFLS. Heterologous expression of MaFLS in Nicotiana tabacum (tobacco) resulted in a reduction in pigmentation in the petals, substantially inhibiting the expression of endogenous tobacco genes involved in anthocyanin biosynthesis (i.e., NtDFR, NtANS, and NtAN2) and upregulating the expression of NtFLS. The total anthocyanin content in the petals of the transformed tobacco plants was dramatically reduced, whereas the total flavonol content was increased. Our study suggests that MaFLS plays a key role in flavonol biosynthesis and flower coloration in grape hyacinth. Moreover, MaFLS may represent a new potential gene for molecular breeding of flower color modification and provide a basis for analyzing the effects of copigmentation on flower coloration in grape hyacinth.
Oxidative Stress: A Key Modulator in Neurodegenerative Diseases
Authors: Singh Anju , Kukreti Ritushree , Saso Luciano , Kukreti Shrikant
Published: April 2019

Oxidative stress is proposed as a regulatory element in ageing and various neurological disorders. The excess of oxidants causes a reduction of antioxidants, which in turn produce an oxidation–reduction imbalance in organisms. Paucity of the antioxidant system generates oxidative-stress, characterized by elevated levels of reactive species (oxygen, hydroxyl free radical, and so on). Mitochondria play a key role in ATP supply to cells via oxidative phosphorylation, as well as synthesis of essential biological molecules. Various redox reactions catalyzed by enzymes take place in the oxidative phosphorylation process. An inefficient oxidative phosphorylation may generate reactive oxygen species (ROS), leading to mitochondrial dysfunction. Mitochondrial redox metabolism, phospholipid metabolism, and proteolytic pathways are found to be the major and potential source of free radicals. A lower concentration of ROS is essential for normal cellular signaling, whereas the higher concentration and long-time exposure of ROS cause damage to cellular macromolecules such as DNA, lipids and proteins, ultimately resulting in necrosis and apoptotic cell death. Normal and proper functioning of the central nervous system (CNS) is entirely dependent on the chemical integrity of brain. It is well established that the brain consumes a large amount of oxygen and is highly rich in lipid content, becoming prone to oxidative stress. A high consumption of oxygen leads to excessive production of ROS. Apart from this, the neuronal membranes are found to be rich in polyunsaturated fatty acids, which are highly susceptible to ROS. Various neurodegenerative diseases such as Parkinson’s disease (PD), Alzheimer’s disease (AD), Huntington’s disease (HD), and amyotrophic lateral sclerosis (ALS), among others, can be the result of biochemical alteration (due to oxidative stress) in bimolecular components. There is a need to understand the processes and role of oxidative stress in neurodegenerative diseases. This review is an effort towards improving our understanding of the pivotal role played by OS in neurodegenerative disorders.
Brassinin Represses Invasive Potential of Lung Carcinoma Cells through Deactivation of PI3K/Akt/mTOR Signaling Cascade
Authors: Yang Min Hee , Lee Jong Hyun , Ko Jeong-Hyeon , Jung Sang Hoon , Sethi Gautam , Ahn Kwang Seok
Published: April 2019

The epithelial–mesenchymal transition (EMT) is a phenomenon that facilitates epithelial cells to acquire invasive potential to induce the initiation the metastatic spread of tumor cells. Here, we determined if brassinin (BSN) can affect the EMT process and deciphered its anti-cancer effects. BSN attenuated the levels of EMT linked genes and suppressed transforming growth factor beta (TGF-β)-mediated regulation of diverse mesenchymal markers. Additionally, BSN did increase the expression of various epithelial marker proteins in lung cancer cells. TGF-β-induced morphological changes and induction of invasive ability of tumor cells was also found to be abrogated by BSN treatment. Finally, BSN not only suppressed constitutive, but also inducible phosphoinositide-3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) phosphorylation in tumor cells.
Evaluation of Polyphenolic Compounds and Pharmacological Activities in Hairy Root Cultures of Ligularia fischeri Turcz. f. spiciformis (Nakai)
Authors: Azam Ansari Mohammad , Chung Ill-Min , Rajakumar Govindasamy , A. Alzohairy Mohammad , Almatroudi Ahmad , Gopiesh Khanna Venkatesan , Thiruvengadam Muthu
Published: April 2019

A considerable amount of bioactive compounds have been used for the biopharmaceutical engineering to help human health and nutrition. Hairy root culture (HRC) or transgenic root is a favourable alternative technique for phytochemical production. Ligularia fischeri is a significant source of pharmaceutically important active compounds with an enormous range of health care applications. HRC of L. fischeri was developed using Agrobacterium rhizogenes for the production of polyphenolic compounds with antioxidant, antimicrobial, antidiabetic, anticancer and anti-inflammatory pharmaceutical activities. Hairy roots (HRs) were selected by morphological assessment, genetic and molecular analyses. The maximum accumulation of fresh mass (94.15 g/L) and dry mass (9.45 g/L) was recorded in MS liquid medium supplemented with 30 g/L sucrose at 28 days. Furthermore, HRs successfully produced numerous polyphenolic compounds, including six hydroxycinnamic acids, seven flavonols, seven hydroxybenzoic acids, vanillin, resveratrol, pyrogallol, homogentisic, and veratric acids, which were identified by UHPLC analysis. HRs produced higher total phenolic (185.65 mg/g), and flavonoid (5.25 mg/g) contents than non-transformed roots (125.55 mg/g and 3.75 mg/g). As a result of these metabolic changes, pharmaceutical activities were found higher in HRs than non-transformed roots (NTRs). The present study indicates that HRC has the potential to increase the content of beneficial polyphenolic compounds with higher potential pharmaceutical activities. To the best of our knowledge, the present study is the first report on enhancing the production of polyphenolic compounds with pharmaceutical activities from the HRCs of L. fischeri.
Could Polyphenols Help in the Control of Rheumatoid Arthritis?
Authors: Sung Siyun , Kwon Doyoung , Um Eunsik , Kim Bonglee
Published: April 2019

Rheumatoid arthritis (RA) is a chronic, systemic, joint-invading, autoimmune inflammatory disease, which causes joint cartilage breakdown and bone damage, resulting in functional impairment and deformation of the joints. The percentage of RA patients has been rising and RA represents a substantial burden for patients around the world. Despite the development of many RA therapies, because of the side effects and low effectiveness of conventional drugs, patients still need and researchers are seeking new therapeutic alternatives. Polyphenols extracted from natural products are effective on several inflammatory diseases, including RA. In this review polyphenols are classified into four types: flavonoids, phenolic acids, stilbenes and others, among which mainly flavonoids are discussed. Researchers have reported that anti-RA efficacies of polyphenols are based mainly on three mechanisms: their anti-inflammatory, antioxidant and apoptotic properties. The main RA factors modified by polyphenols are mitogen-activated protein kinase (MAPK), interleukin-1β (IL-1β), IL-6, tumor necrosis factor-α (TNF-α), nuclear factor κ light chain enhancer of activated B cells (NF-κB) and c-Jun N-terminal kinases (JNK). Polyphenols could be potent alternative RA therapies and sources for novel drugs for RA by affecting its key mechanisms.
Tuscan Varieties of Sweet Cherry Are Rich Sources of Ursolic and Oleanolic Acid: Protein Modeling Coupled to Targeted Gene Expression and Metabolite Analyses
Authors: Berni Roberto , Hoque Mubasher Zahir , Legay Sylvain , Cai Giampiero , Siddiqui Khawar Sohail , Hausman Jean-Francois , Andre Christelle M. , Guerriero Gea
Published: April 2019

The potential of six ancient Tuscan sweet cherry (Prunus avium L.) varieties as a source of health-promoting pentacyclic triterpenes is here evaluated by means of a targeted gene expression and metabolite analysis. By using a sequence homology criterion, we identify five oxidosqualene cyclase genes (OSCs) and three cytochrome P450s (CYP85s) that are putatively involved in the triterpene production pathway in sweet cherries. We performed 3D structure prediction and induced-fit docking using cation intermediates and reaction products for some OSCs to predict their function. We show that the Tuscan varieties have different amounts of ursolic and oleanolic acids and that these variations are related to different gene expression profiles. This study stresses the interest of valorizing ancient fruits as alternative sources of functional molecules with nutraceutical value. It also provides information on sweet cherry triterpene biosynthetic genes, which could be the object of follow-up functional studies.
Synthesis of a Fluorous-Tagged Hexasaccharide and Interaction with Growth Factors Using Sugar-Coated Microplates
Authors: Maza Susana , de Paz José L. , Nieto Pedro M.
Published: April 2019

Here, we report the synthesis of a sulfated, fully protected hexasaccharide as a glycosaminoglycan mimetic and the study of its interactions with different growth factors: midkine, basic fibroblast growth factor (FGF-2) and nerve growth factor (NGF). Following a fluorous-assisted approach, monosaccharide building blocks were successfully assembled and the target oligosaccharide was prepared in excellent yield. The use of more acid stable 4,6-O-silylidene protected glucosamine units was crucial for the efficiency of this strategy because harsh reaction conditions were needed in the glycosylations to avoid the formation of orthoester side products. Fluorescence polarization experiments demonstrated the strong interactions between the synthesized hexamer, and midkine and FGF-2. In addition, we have developed an alternative assay to analyse these molecular recognition events. The prepared oligosaccharide was non-covalently attached to a fluorous-functionalized microplate and the direct binding of the protein to the sugar-immobilized surface was measured, affording the corresponding KD,surf value.
Tactile Cues for Improving Target Localization in Subjects with Tunnel Vision
Authors: Camors Damien , Appert Damien , Durand Jean-Baptiste , Jouffrais Christophe
Published: April 2019

The loss of peripheral vision is experienced by millions of people with glaucoma or retinitis pigmentosa, and has a major impact in everyday life, specifically to locate visual targets in the environment. In this study, we designed a wearable interface to render the location of specific targets with private and non-intrusive tactile cues. Three experimental studies were completed to design and evaluate the tactile code and the device. In the first study, four different tactile codes (single stimuli or trains of pulses rendered either in a Cartesian or a Polar coordinate system) were evaluated with a head pointing task. In the following studies, the most efficient code, trains of pulses with Cartesian coordinates, was used on a bracelet located on the wrist, and evaluated during a visual search task in a complex virtual environment. The second study included ten subjects with a simulated restrictive field of view (10°). The last study consisted of proof of a concept with one visually impaired subject with restricted peripheral vision due to glaucoma. The results show that the device significantly improved the visual search efficiency with a factor of three. Including object recognition algorithm to smart glass, the device could help to detect targets of interest either on demand or suggested by the device itself (e.g., potential obstacles), facilitating visual search, and more generally spatial awareness of the environment.
Neutron Radiography Study of Laboratory Ageing and Treatment Applications with Stone Consolidants
Authors: Ban Matea , De Kock Tim , Ott Frédéric , Barone Germana , Rohatsch Andreas , Raneri Simona
Published: April 2019

A nano-silica consolidant and nano-titania modified tetraethyl-orthosilicate were applied on two building stones, a carbonate and a silicate, by brush, poultice or capillary absorption. Neutron radiography was used to monitor capillary water absorption, and to analyse changes in physical properties caused by heat treatment of specimens for the purposes of artificially ageing and different treatment applications with stone consolidants. Moreover, ultrasonic pulse velocity and gravimetrically determined water absorption were analysed to cross-validate neutron radiography. The results reveal that reactive systems like tetraethyl-orthosilicates need an unknown period for polymerisation, which makes nano-silica consolidants more favourable for construction follow-up work. While polymerisation is incomplete, hydrophobic behaviour, water trapping and pore clogging are evident. Within the tetraethyl-orthosilicate treatment, poultice and brushing are strongly influenced by the applicant, which results in wide ranging amounts of water absorbed and anomalous water distributions and kinetics. The carbonate lithotype displays polymerisation initiated in the core of the specimen, while the lateral surfaces are still mostly hydrophobic. Reaction time differences can be attributed to the different amounts of consolidants applied, which is a result of the chosen application settings. Artificial ageing of stone specimens is a prerequisite when mechanical strength gain is studied, as demonstrated by sound speed propagation.
Effect of Electrospun Fiber Mat Thickness and Support Method on Cell Morphology
Authors: Calhoun Mark A. , Chowdhury Sadiyah Sabah , Nelson Mark Tyler , Lannutti John J. , Dupaix Rebecca B. , Winter Jessica O.
Published: April 2019

Electrospun fiber mats (EFMs) are highly versatile biomaterials used in a myriad of biomedical applications. Whereas some facets of EFMs are well studied and can be highly tuned (e.g., pore size, fiber diameter, etc.), other features are under characterized. For example, although substrate mechanics have been explored by several groups, most studies rely on Young’s modulus alone as a characterization variable. The influence of fiber mat thickness and the effect of supports are variables that are often not considered when evaluating cell-mechanical response. To assay the role of these features in EFM scaffold design and to improve understanding of scaffold mechanical properties, we designed EFM scaffolds with varying thickness (50–200 µm) and supporting methodologies. EFM scaffolds were comprised of polycaprolactone and were either electrospun directly onto a support, suspended across an annulus (3 or 10 mm inner diameter), or “tension-released” and then suspended across an annulus. Then, single cell spreading (i.e., Feret diameter) was measured in the presence of these different features. Cells were sensitive to EFM thickness and suspended gap diameter. Overall, cell spreading was greatest for 50 µm thick EFMs suspended over a 3 mm gap, which was the smallest thickness and gap investigated. These results are counterintuitive to conventional understanding in mechanobiology, which suggests that stiffer materials, such as thicker, supported EFMs, should elicit greater cell polarization. Additional experiments with 50 µm thick EFMs on polystyrene and polydimethylsiloxane (PDMS) supports demonstrated that cells can “feel” the support underlying the EFM if it is rigid, similar to previous results in hydrogels. These results also suggest that EFM curvature may play a role in cell response, separate from Young’s modulus, possibly because of internal tension generated. These parameters are not often considered in EFM design and could improve scaffold performance and ultimately patient outcomes.
Boron Nitride Doped Polyhydroxyalkanoate/Chitosan Nanocomposite for Antibacterial and Biological Applications
Authors: Mukheem Abdul , Shahabuddin Syed , Akbar Noor , Miskon Azizi , Muhamad Sarih Norazilawati , Sudesh Kumar , Ahmed Khan Naveed , Saidur Rahman , Sridewi Nanthini
Published: April 2019

The present research focused on the fabrication of biocompatible polyhydroxyalkanoate, chitosan, and hexagonal boron nitride incorporated (PHA/Ch-hBN) nanocomposites through a simple solvent casting technique. The fabricated nanocomposites were comprehensively characterized by Fourier transform infrared spectroscope (FT-IR), field emission scanning electroscope (FESEM), and elemental mapping and thermogravimetric analysis (TGA). The antibacterial activity of nanocomposites were investigated through time-kill method against multi drug resistant (MDR) microbes such as methicillin-resistant Staphylococcus aureus (MRSA) and Escherichia coli (E. coli) K1 strains. In addition, nanocomposites have examined for their host cytotoxicity abilities using a Lactate dehydrogenase (LDH) assay against spontaneously immortalized human keratinocytes (HaCaT) cell lines. The results demonstrated highly significant antibacterial activity against MDR organisms and also significant cell viability as compared to the positive control. The fabricated PHA/Ch-hBN nanocomposite demonstrated effective antimicrobial and biocompatibility properties that would feasibly suit antibacterial and biomedical applications.
How to Prevent Loss of Muscle Mass and Strength among Older People in Neuro-Rehabilitation?
Authors: Lathuilière Aurélien , Mareschal Julie , Graf Christophe E.
Published: April 2019

Stroke is the second leading cause of death worldwide but also of disability. Stroke induces certain alterations of muscle metabolism associated with gross muscle atrophy and a decrease in muscle function, leading to sarcopenia. The vast majority of stroke cases occur in adults over 65 years of age, and the prevalence is expected to massively increase in the coming years in this population. Sarcopenia is associated with higher mortality and functional decline. Therefore, the identification of interventions that prevent muscle alterations after stroke is of great interest. The purpose of this review is to carry out a systematic literature review to identify evidence for nutritional and pharmacological interventions, which may prevent loss of muscle mass in the elderly after stroke. The search was performed on Medline in December 2018. Randomized controlled studies, observational studies and case reports conducted in the last 20 years on post-stroke patients aged 65 or older were included. In total, 684 studies were screened, and eight randomized control trials and two cohort studies were finally included and examined. This review reveals that interventions such as amino acid supplementation or anabolic steroid administration are efficient to prevent muscle mass. Little evidence is reported on nutritional aspects specifically in sarcopenia prevention after stroke. It pinpoints the need for future studies in this particular population.
The Contribution of Host Cells to Pneumocystis Immunity: An Update
Authors: Otieno-Odhiambo Patricia , Wasserman Sean , Hoving J. Claire
Published: April 2019

Pneumocystis is a ubiquitous atypical fungus that is distributed globally. The genus comprises morphologically similar but genetically heterogeneous species that have co-evolved with specific mammalian hosts as obligate intra-pulmonary pathogens. In humans, Pneumocystis jirovecii is the causative organism of Pneumocystis pneumonia (PCP) in immunocompromised individuals, a serious illness frequently leading to life-threatening respiratory failure. Initially observed in acquired immunodeficiency syndrome (AIDS) patients, PCP is increasingly observed in immunocompromised non-AIDS patients. The evolving epidemiology and persistently poor outcomes of this common infection will require new strategies for diagnosis and treatment. A deeper understanding of host immune responses and of the cells that mediate them will improve the chance of developing new treatment strategies. This brief review provides an update on recent studies on the role of host immunity against Pneumocystis.
Art in the Face of Evil: Analogies between the Conceptions of Two French Resistance Fighters
Authors: Carciofi Estelle
Published: April 2019

I present two conceptions of the human being and art: that of Renaud—the main fictional character of a short novel written by Vercors—and that of Albert Camus. Although these French resistance fighters experienced the same war, the same terrible events surprisingly lead them to opposite extremes: the first one to despair and the rejection of art perceived as an unbearable lie, the second one to hope and to artistic commitment. Analogical reasoning allows us to show both the similarities and the distinctions between these two men or, more precisely, between what they tell us about human beings and art. Thanks to this, it is easier to understand the essential role the artist plays and his duty towards humankind. Moreover, in the work of Albert Camus, we will see that revolt is—and must be—connected to love.
Remote Presence: Development and Usability Evaluation of a Head-Mounted Display for Camera Control on the da Vinci Surgical System
Authors: Dardona Tareq , Eslamian Shahab , Reisner Luke A. , Pandya Abhilash
Published: April 2019

This paper describes the development of a new method to control the camera arm of a surgical robot and create a better sense of remote presence for the surgeon. The current surgical systems are entirely controlled by the surgeon, using hand controllers and foot pedals to manipulate either the instrument or the camera arms. The surgeon must pause the operation to move the camera arm to obtain a desired view and then resume the operation. The camera and tools cannot be moved simultaneously, leading to interrupted and unnatural movements. These interruptions can lead to medical errors and extended operation times. In our system, the surgeon controls the camera arm by his natural head movements while being immersed in a 3D-stereo view of the scene with a head-mounted display (HMD). The novel approach enables the camera arm to be maneuvered based on sensors of the HMD. We implemented this method on a da Vinci Standard Surgical System using the HTC Vive headset along with the Unity engine and the Robot Operating System framework. This paper includes the result of a subjective six-participant usability study that compares the workload of the traditional clutched camera control method against the HMD-based control. Initial results indicate that the system is usable, stable, and has a lower physical and mental workload when using the HMD control method.
Preface: Remote Sensing for Flood Mapping and Monitoring of Flood Dynamics
Authors: Domeneghetti Alessio , Schumann Guy J.-P. , Tarpanelli Angelica
Published: April 2019

This Special Issue is a collection of papers that focus on the use of remote sensing data and describe methods for flood monitoring and mapping. These articles span a wide range of topics; present novel processing techniques and review methods; and discuss limitations and challenges. This preface provides a brief overview of the content.
Effects of UAV Image Resolution, Camera Type, and Image Overlap on Accuracy of Biomass Predictions in a Tropical Woodland
Authors: Domingo Darío , Ørka Hans Ole , Næsset Erik , Kachamba Daud , Gobakken Terje
Published: April 2019

Unmanned aerial systems (UASs) and photogrammetric structure from motion (SFM) algorithms can assist in biomass assessments in tropical countries and can be a useful tool in local greenhouse gas accounting. This study assessed the influence of image resolution, camera type and side overlap on prediction accuracy of biomass models constructed from ground-based data and UAS data in miombo woodlands in Malawi. We compared prediction accuracy of models reflecting two different image resolutions (10 and 15 cm ground sampling distance) and two camera types (NIR and RGB). The effect of two different side overlap levels (70 and 80%) was also assessed using data from the RGB camera. Multiple linear regression models that related the biomass on 37 field plots to several independent 3-dimensional variables derived from five UAS acquisitions were constructed. Prediction accuracy quantified by leave-one-out cross validation increased when using finer image resolution and RGB camera, while coarser resolution and NIR data decreased model prediction accuracy, although no significant differences were observed in absolute prediction error around the mean between models. The results showed that a reduction of side overlap from 80 to 70%, while keeping a fixed forward overlap of 90%, might be an option for reducing flight time and cost of acquisitions. Furthermore, the analysis of terrain slope effect in biomass predictions showed that error increases with steeper slopes, especially on slopes greater than 35%, but the effects were small in magnitude.
Coastal Wetland Mapping with Sentinel-2 MSI Imagery Based on Gravitational Optimized Multilayer Perceptron and Morphological Attribute Profiles
Authors: Zhang Aizhu , Sun Genyun , Ma Ping , Jia Xiuping , Ren Jinchang , Huang Hui , Zhang Xuming
Published: April 2019

Coastal wetland mapping plays an essential role in monitoring climate change, the hydrological cycle, and water resources. In this study, a novel classification framework based on the gravitational optimized multilayer perceptron classifier and extended multi-attribute profiles (EMAPs) is presented for coastal wetland mapping using Sentinel-2 multispectral instrument (MSI) imagery. In the proposed method, the morphological attribute profiles (APs) are firstly extracted using four attribute filters based on the characteristics of wetlands in each band from Sentinel-2 imagery. These APs form a set of EMAPs which comprehensively represent the irregular wetland objects in multiscale and multilevel. The EMAPs and original spectral features are then classified with a new multilayer perceptron (MLP) classifier whose parameters are optimized by a stability-constrained adaptive alpha for a gravitational search algorithm. The performance of the proposed method was investigated using Sentinel-2 MSI images of two coastal wetlands, i.e., the Jiaozhou Bay and the Yellow River Delta in Shandong province of eastern China. Comparisons with four other classifiers through visual inspection and quantitative evaluation verified the superiority of the proposed method. Furthermore, the effectiveness of different APs in EMAPs were also validated. By combining the developed EMAPs features and novel MLP classifier, complicated wetland types with high within-class variability and low between-class disparity were effectively discriminated. The superior performance of the proposed framework makes it available and preferable for the mapping of complicated coastal wetlands using Sentinel-2 data and other similar optical imagery.
Satellite Remote Sensing Signatures of the Major Baltic Inflows
Authors: Stramska Malgorzata , Aniskiewicz Paulina
Published: April 2019

Variability of sea level in the North and Baltic Seas, enforced by weather patterns, affects the intensity of water exchange between these seas. Transfer of salty water from the North Sea is very important for the hydrography of the Baltic Sea. The volume of inflowing salty water can occasionally increase remarkably. Such incidents, called the Major Baltic Inflows (MBIs), are unpredictable, of relatively short duration, and difficult to observe using in situ data. We have shown that remote sensing altimetry can be used as a complementary source of information about the MBI events. The advantage of using such data is that large-scale spatial information about SLA is available with daily resolution. We have described changes in SLA during several MBI events observed in 1993–2017. The net volume of water transported into the Baltic Sea varied between the events due to differences in atmospheric forcing. Based on SLA data, the largest inflow of water happened during the 2014 MBI. This is in agreement with previously published results, based on in situ data.
Mangrove Phenology and Environmental Drivers Derived from Remote Sensing in Southern Thailand
Authors: Songsom Veeranun , Koedsin Werapong , Ritchie Raymond J. , Huete Alfredo
Published: April 2019

Vegetation phenology is the annual cycle timing of vegetation growth. Mangrove phenology is a vital component to assess mangrove viability and includes start of season (SOS), end of season (EOS), peak of season (POS), and length of season (LOS). Potential environmental drivers include air temperature (Ta), surface temperature (Ts), sea surface temperature (SST), rainfall, sea surface salinity (SSS), and radiation flux (Ra). The Enhanced vegetation index (EVI) was calculated from Moderate Resolution Imaging Spectroradiometer (MODIS, MOD13Q1) data over five study sites between 2003 and 2012. Four of the mangrove study sites were located on the Malay Peninsula on the Andaman Sea and one site located on the Gulf of Thailand. The goals of this study were to characterize phenology patterns across equatorial Thailand Indo-Malay mangrove forests, identify climatic and aquatic drivers of mangrove seasonality, and compare mangrove phenologies with surrounding upland tropical forests. Our results show the seasonality of mangrove growth was distinctly different from the surrounding land-based tropical forests. The mangrove growth season was approximately 8–9 months duration, starting in April to June, peaking in August to October and ending in January to February of the following year. The 10-year trend analysis revealed significant delaying trends in SOS, POS, and EOS for the Andaman Sea sites but only for EOS at the Gulf of Thailand site. The cumulative rainfall is likely to be the main factor driving later mangrove phenologies.
Sun-Induced Chlorophyll Fluorescence I: Instrumental Considerations for Proximal Spectroradiometers
Authors: Pacheco-Labrador Javier , Hueni Andreas , Mihai Laura , Sakowska Karolina , Julitta Tommaso , Kuusk Joel , Sporea Dan , Alonso Luis , Burkart Andreas , Cendrero-Mateo M. Pilar , Aasen Helge , Goulas Yves , Mac Arthur Alasdair
Published: April 2019

Growing interest in the proximal sensing of sun-induced chlorophyll fluorescence (SIF) has been boosted by space-based retrievals and up-coming missions such as the FLuorescence EXplorer (FLEX). The European COST Action ES1309 “Innovative optical tools for proximal sensing of ecophysiological processes” (OPTIMISE, ES1309; https://optimise.dcs.aber.ac.uk/) has produced three manuscripts addressing the main current challenges in this field. This article provides a framework to model the impact of different instrument noise and bias on the retrieval of SIF; and to assess uncertainty requirements for the calibration and characterization of state-of-the-art SIF-oriented spectroradiometers. We developed a sensor simulator capable of reproducing biases and noises usually found in field spectroradiometers. First the sensor simulator was calibrated and characterized using synthetic datasets of known uncertainties defined from laboratory measurements and literature. Secondly, we used the sensor simulator and the characterized sensor models to simulate the acquisition of atmospheric and vegetation radiances from a synthetic dataset. Each of the sensor models predicted biases with propagated uncertainties that modified the simulated measurements as a function of different factors. Finally, the impact of each sensor model on SIF retrieval was analyzed. Results show that SIF retrieval can be significantly affected in situations where reflectance factors are barely modified. SIF errors were found to correlate with drivers of instrumental-induced biases which are as also drivers of plant physiology. This jeopardizes not only the retrieval of SIF, but also the understanding of its relationship with vegetation function, the study of diel and seasonal cycles and the validation of remote sensing SIF products. Further work is needed to determine the optimal requirements in terms of sensor design, characterization and signal correction for SIF retrieval by proximal sensing. In addition, evaluation/validation methods to characterize and correct instrumental responses should be developed and used to test sensors performance in operational conditions.