bluuebunny/crossref_metadata_2025 huggingface dataset:
Low frequency electric polarizability and zeta-potential of Escherichia coli HB101 (K-12) cells during inactivation with ethanol
Authors: Gyurova Anna , Doltchinkova Verjinia , Georgieva Ralica , Danova Svetla , Stoylov Stoyl
Published: February 2013

The electric properties of bacteria determine their non-specific interactions with the environment, in particular their pathogenic activity. The electric polarizability of Escherichia coli HB101 (K-12 strain) was studied while inactivation with ethanol (20–40 vol.%). The current investigation might be regarded as a continuation of previous research on the polarizability of E. coli at lower ethanol concentration (≤ 20 vol.%) and higher frequencies (≥ 20 kHz). The bacteria polarizability at low frequencies (4 Hz) shows anomalies (unexpected increase in the polarizability at certain ethanol concentrations), while the parameter decreases with an increase in the ethanol concentration at higher frequencies. We investigated for the possible reasons causing the anomalies — in our case reduced to the medium dielectric permittivity, the average cell length and the surface electric charge density distribution, related to bacterial lipopolysaccharides. We suggest a hypothesis for the molecular mechanism of changing the surface charge of E. coli, carried by lipopolysaccharides, induced by the non-ionic ethanol.
Voltammetric method for ultra-trace determination of total mercury and toxic metals in vegetables. Comparison with spectroscopy
Authors: Locatelli Clinio , Melucci Dora
Published: February 2013

A new procedure for the determination of mercury(II), copper(II), lead(II), cadmium(II) and zinc(II) traces in food matrices by square wave anodic stripping voltammetry and standard addition method is proposed. A rapid, inexpensive and multi-analyte analytical method suitable for food safety control is provided. Comestible vegetables were chosen as samples. A two-step, sequential determination was defined, employing two working electrodes: a gold electrode (GE) for mercury(II) and copper(II), and subsequently a hanging mercury drop electrode (HMDE) for copper(II), lead(II), cadmium(II) and zinc(II). No sample pre-treatment was needed. Spinach leaves, tomato leaves and apple leaves were employed as standard reference materials to optimize and defined the analytical procedure. The new method shows good selectivity, sensitivity, detectability and accuracy. A critical comparison with spectroscopic measurements is discussed. Spinach, lettuce and tomato samples sold on the market were analysed as real samples. Lead(II) and cadmium(II) concentration exceeded the relevant legal limits.
Density, Spatial Pattern and Relief Features of Sacred Sites in Northern Morocco
Authors: Jäckle Holger , Rudner Michael , Deil Ulrich
Published: February 2013

Sacred sites are of conservation value because of their spiritual meaning, as cultural heritage and as remnants of near-natural biotopes in landscapes strongly transformed by man. The vegetation of sacred sites in Morocco was studied recently. Information about their number, spatial pattern or relief position is fragmentary. However, these parameters are important to evaluate their role as refuge for organisms and their representativeness of potential natural vegetation. Therefore, density and spatial pattern of sacred sites on the Tangier Peninsula in NW Morocco were studied based on records on topographic maps and by ground check. Their relief position was examined calculating a logistic regression model based on site-presences and random pseudo-absences. A ground check showed that around 67% of the existing sacred sites are documented in the topographic maps. They occur in the whole study area but are agglomerated around settlements. Although sacred sites occur with preference at elevated sites they can be found in almost all relief positions, thus offering the potential of supporting different types of climax vegetation (climatic climax and pedoclimax). Because of their abundance (around 29 sacred sites / 100 km2) and their distribution pattern they could serve as elements of a biotope network in degraded landscapes.
Impact of Bus Rapid Transit Systems on Road Safety
Authors: Bocarejo Juan Pablo , Velasquez Juan Miguel , Díaz Claudia Andrea , Tafur Luis Eduardo
Published: February 2013

TransMilenio, a high-capacity bus rapid transit (BRT) system, was gradually implemented in important corridors of Bogotá, Colombia, during the past decade. The main objective was to achieve major improvements in the provision of public transport, especially in capacity and speed. However, there have been significant effects on road safety. Data from two corridors, Caracas Avenue and Norte-Quito-Sur Avenue, were analyzed with geographic information system techniques. Before and after situations were compared to assess the impacts on road safety of the implementation of these BRT corridors. Although the results suggest that TransMilenio brought about important overall reductions in traffic accidents, specific areas have seen an increase. This increase occurred mainly around the busiest stations, but it was also observed on the roads, where speed went up significantly as a result of the elimination of traffic lights, the widening of space for private cars, and the general improvement of the road surface. Analysis of the Bogotá experience reveals this lesson: special consideration must be given to improving pedestrian facilities along high-speed corridors and around busy stations in the design of future BRT corridors.
Understanding Road Safety Impact of High-Performance Bus Rapid Transit and Busway Design Features
Authors: Duduta Nicolae , Adriazola Claudia , Hidalgo Dario , Lindau Luis Antonio , Jaffe Rebecca
Published: February 2013

The design choices made in the planning of a new bus rapid transit (BRT) or busway corridor (e.g., use of a center-lane or curbside configuration, counterflow lanes, and open or closed stations) affect not only the operational performance of the system but also the risks of crashes, injuries, and fatalities on the facility over its lifetime. With data from nine BRT systems and busways around the world (including Bogotá, Colombia; Curitiba, Brazil; Mexico City, Mexico; and Delhi, India), some of the road safety impacts of major BRT–busway corridor design characteristics are illustrated. The approach included a combination of crash frequency modeling, road safety inspections, and interviews with transit agency staff and safety experts. Center-lane systems tended generally to be safer than were curbside systems, and counter flow lanes were the most dangerous possible configuration. Some of the features that provide higher passenger capacity (such as multiple bus lanes and multiple docking bays at stations) may introduce new types of conflicts and crashes. In the planning of any bus system, trade-offs often need to be made between capacity, safety, and pedestrian accessibility along the corridor. This study provides the necessary elements for successfully integrating road safety considerations into the design and operation of future BRT systems and busways.
Buses as Low-Carbon Mobility Solutions for Urban India
Authors: Prabhu Ashwin , Pai Madhav
Published: February 2013

Promoting the use of public transport is seen as one of the key strategies for moderating the inevitable growth of carbon emissions from urban transport in India. For the majority of Indian cities, this means promoting the use of public bus systems. However, the absence of analyses on carbon emissions savings attributable to public bus services in Indian cities creates a significant gap in the literature. This study used recently available data on bus system performance, travel characteristics, and emissions factors to estimate the emissions savings from public bus services in two cities, Ahmedabad and Bangalore. Three types of emissions savings estimates were calculated: past savings from increased ridership in the 5 years from 2005 to 2010, current savings from the newly introduced Janmarg bus rapid transit system in Ahmedabad and the Big10 trunk services in Bangalore, and forecasted savings for 2021 and 2031. All three estimates indicated that public bus services produce significant reductions in carbon emissions. The advantages of investing in bus systems (relatively low cost and quick implementation) over other potential strategies for reducing urban transport emissions suggest that bus systems should be a high priority for both governments and international funding mechanisms for mitigation of climate change.
Motorized Vehicle Purchase in Surat, India
Authors: Banerjee Ipsita , Kanafani Adib , Walker Joan L.
Published: February 2013

As India's economy grows, so does its rate of car ownership. Motorized two-wheelers had been the prevalent mode of personal transport in the country. With improving economic conditions, more households are buying and using cars, and large cars are being introduced in a market that consisted primarily of small cars. This study assessed the trends in the future composition of motorized vehicles in the Indian city of Surat by analyzing a cross section of consumer purchases across used and new motorized vehicles, namely, two-wheelers and different size categories of cars. The findings have potential use in informing policies on infrastructure development and in controlling the negative externalities of car use. Data were obtained through home interview surveys of Surat residents who had recently purchased a motorized vehicle. To explain the vehicle choices of these residents, different observed attributes of the vehicles and their owners were considered. It was hypothesized that latent attributes (e.g., careful spender behavior, perception of status, and negative image of nonmotorized and public modes) may play an important role in the choice of personal vehicles, which are prohibitively expensive in India. To test this hypothesis, latent attributes were obtained as explanatory variables through factor analysis of responses to Likert scale questions pertaining to such attitudes and incorporated into the model. An integrated choice and latent variable model was used for this analysis. The results indicate that while household size does affect the size of vehicle purchased, small vehicles, in addition to lower fuel costs and larger engines, are generally preferred. The results further indicate that observed variables are more significant than latent ones in explaining vehicle choice.
Evaluation of Effects of Car Ownership Policies in Chinese Megacities
Authors: Chen Xiaohong , Zhang Hua
Published: February 2013

At the beginning of the catching-up phenomenon of personal motorization in China, two very different car ownership policies were implemented in megacities: Beijing adopted a no intervention policy and Shanghai adopted a license quota policy. This difference provides an opportunity to examine policy impacts on car ownership and usage. The effects of the two policies on car ownership levels and delays in the process of personal motorization were examined. The growth pattern of car ownership without intervention was estimated on the basis of city-level aggregate data and a principal component analysis. The results indicate that an increase in income is the dominant factor driving the growth of car ownership in China. The forecast result in Shanghai indicates that the limitation policy has suppressed car ownership by at least twice as many individuals as the number of individuals who actually own cars. The limited car ownership policy also delays the process of personal motorization; this delay provides authorities with more time and chances to improve alternative transport services to fill the demand for motorized travel. The practical experience in Shanghai and public attitude responses in Beijing emphasize the importance of supporting measures to complement the limited car ownership policy and the need to offer equitable car ownership opportunities for all groups.
Investigating Bicyclists’ Perception of Comfort on Physically Separated Bicycle Paths in Nanjing, China
Authors: Li Zhibin , Wang Wei , Liu Pan , Schneider Robert , Ragland David R.
Published: February 2013

Providing bicyclists favorable and comfortable riding environments is an important objective for transportation professionals. This study investigated the factors that contribute to bicyclists’ perception of comfort on physically separated bicycle paths and quantified their impacts. A survey was conducted on 29 physically separated bicycle paths in the metropolitan area of Nanjing, China. A factor analysis and an ordered probit model were used to analyze the data. The results showed that the mean perception of comfort was significantly different between age groups, but not significantly different between gender groups and between users of electric bicycles and conventional bicycles. The model performance indicated that the ordered probit model with factor analysis addressed the correlation between independent variables and outperformed the ordered probit model without factor analysis. The model estimates showed that bicyclists’ perception of comfort on physically separated bicycle paths was significantly influenced by physical environmental factors, including the width of the bicycle pathway, the width of the shoulder, the presence of grade, the presence of a bus stop, the surrounding land use, and the flow rate of electric and conventional bicycles. The findings yielded insights into bicyclists’ psychological perception of comfort on physically separated bicycle paths. This research can help inform the design and planning of these facilities.
Behavior of Riders of Electric Bicycles at Onset of Green and Yellow at Signalized Intersections in China
Authors: Tang Keshuang , Dong Sheng , Wang Fen , Ni Ying , Sun Jian
Published: February 2013

In most Chinese cities, electric bicycles and electrically assisted bicycles (e-bikes) have drastically increased in recent years and currently constitute the largest proportion of the nonmotorized traffic at signalized intersections. Proper treatment of e-bikes has become a vitally important issue in improving the operational efficiency and safety performance of signalized intersections. However, fundamental knowledge of the unique operating characteristics and behavior of riders of e-bikes under various conditions is insufficient. This study statistically analyzed critical behavioral parameters of e-bike riders and empirically modeled their start-up behavior at the green onset following a 3-s red-and-yellow signal and their stop–pass decision behavior at the yellow onset following a 3-s flashing green. Distribution types and parameters of desired speed, start-up time, acceleration rate, perception–reaction time, and deceleration rate were investigated with the use of highly accurate trajectory data. A temporal–spatial model was developed to interpret the start-up curve, and three binary logistic regression models were built to predict the stop–pass decisions for different rider groups. It was found that the start-up curve of e-bikes could be well described by a quadratic function and that the red-and-yellow signal significantly induced a hurried start. The potential time to the stop line at the decision point was found to be the dominant independent factor explaining the stop–pass decision of e-bike riders; the flashing green signal seemed to enlarge the option zone, bring the indecision zone earlier, and result in more aggressive passing behavior.
Investigation and Analysis of Motorcycle Safety in Rural China
Authors: He Jie , Shi Xiaojie , Xu Zhong , Hang Wen
Published: February 2013

To determine the causes of and countermeasures for motorcycle accidents in rural areas of China, a study was undertaken to consider three primary contributors to such accidents: people, vehicles, and management. A self-report questionnaire was developed and administered to a sample of motorcycle riders (n = 480) in Linyi, Shandong Province. All statistical analyses were performed with SPSS, Version 17.0. Four hundred and three valid questionnaires were collected, only 60 of which recorded drivers with a license. Many riders carried passengers (74.9%) or goods (62.5%) on their motorcycles. Although the rate of helmet use among these motorcyclists was low, speeding and drunk driving were prevalent. The results consistently showed that in rural areas, motorcyclists had little awareness of traffic safety and that risky driving behavior was common among them. Therefore, education and prevention strategies need to be targeted at motorcycle riders to enhance their safety awareness. Administrative officials must also strengthen their management of motorcycles in rural areas.
Development of Congestion Cost Equations for Multilane Highways in India
Authors: Velmurugan S. , Madhu Errampalli , Nataraju Jakkula , Ravinder Kayitha
Published: February 2013

Traffic congestion is a tremendous drain on the economy of any nation. Congestion imposes vehicle operating costs and time costs on the road user that are in addition to the normal costs for using the same road under uncongested conditions. Fuel cost, as the major share of the vehicle operating cost, and time cost are the two relevant parameters for assessing the influence of congestion; fuel consumption and time cost equations must be able to estimate congestion cost. This study assessed fuel consumption and travel time costs under congested conditions on multilane highways, including four-, six-, and eight-lane divided carriageways. Data were collected from fuel consumption experiments conducted under a congested state and from roadside surveys on the value of time for different types of road users, including both passengers and goods. With these data, the authors developed congestion cost equations for fuel and time costs for different vehicle types that can be used to calculate the effects of congestion on fuel and time costs of vehicles operating on multilane highways.
Conducting Transportation Survey Research in China
Authors: Ni Meng-Cheng , Cherry Christopher , Deakin Elizabeth
Published: February 2013

Rapid changes in transportation choices and travel patterns accompanying China's economic development have led many international agencies and nongovernmental organizations to get involved in transportation planning and analysis in Chinese cities. Some of their work is project oriented, in partnership with the national government or city governments, and some is research conducted in cooperation with local universities, research groups, and government agencies. Both kinds of work need high-quality data, but because growth and change are so rapid, official data sources may be outdated or may provide insufficient spatial coverage, insufficient sample sizes, or incomplete topical coverage. Thus planners and researchers must often conduct special studies involving survey research on such topics as choice of household location, travel and activity patterns, choice of vehicle type, and travel preferences and behavior. Although survey methodologies are well developed in the West, some modifications are needed when applying these methods in China. Strategies for successful survey research in Chinese cities are discussed, with an emphasis on lessons learned in recent survey deployments in Shanghai, Jinan, and Kunming. Successful approaches for obtaining access to respondents are considered, and issues that can arise in survey implementation are examined. Best practices involve coupling authorization letters from cooperating organizations or sponsors with convincing and trustworthy promises of respondent anonymity or confidentiality; extensive training, including practice runs, for local teams administering the surveys; and use of incentives, such as small gifts, to facilitate the first contact.
Recycling of Waste Engine Oils Using a New Washing Agent
Authors: Hamawand Ihsan , Yusaf Talal , Rafat Sardasht
Published: February 2013

This paper addresses recycling of waste engine oils treated using acetic acid. A recycling process was developed which eventually led to comparable results with some of the conventional methods. This gives the recycled oil the potential to be reused in cars’ engines after adding the required additives. The advantage of using the acetic acid is that it does not react or only reacts slightly with base oils. The recycling process takes place at room temperature. It has been shown that base oils and oils’ additives are slightly affected by the acetic acid. Upon adding 0.8 vol% of acetic acid to the used oil, two layers were separated, a transparent dark red colored oil and a black dark sludge at the bottom of the container. The base oils resulting from other recycling methods were compared to the results of this paper. The comparison showed that the recycled oil produced by acetic acid treatment is comparable to those recycled by the other conventional methods.
Exergy and Exergoeconomic Model of a Ground-Based CAES Plant for Peak-Load Energy Production
Authors: Buffa Francesco , Kemble Simon , Manfrida Giampaolo , Milazzo Adriano
Published: February 2013

Compressed Air Energy Storage is recognized as a promising technology for applying energy storage to grids which are more and more challenged by the increasing contribution of renewable such as solar or wind energy. The paper proposes a medium-size ground-based CAES system, based on pressurized vessels and on a multiple-stage arrangement of compression and expansion machinery; the system includes recovery of heat from the intercoolers, and its storage as sensible heat in two separate (hot/cold) water reservoirs, and regenerative reheat of the expansions. The CAES plant parameters were adapted to the requirements of existing equipment (compressors, expanders and heat exchangers). A complete exergy analysis of the plant was performed. Most component cost data were procured from the market, asking specific quotations to the industrial providers. It is thus possible to calculate the final cost of the electricity unit (kWh) produced under peak-load mode, and to identify the relative contribution between the two relevant groups of capital and component inefficiencies costs.
5-bp Classical Satellite DNA Loci from Chromosome-1 Instability in Cervical Neoplasia Detected by DNA Breakage Detection/Fluorescence in Situ Hybridization (DBD-FISH)
Authors: Cortés-Gutiérrez Elva , Ortíz-Hernández Brenda , Dávila-Rodríguez Martha , Cerda-Flores Ricardo , Fernández José , López-Fernández Carmen , Gosálvez Jaime
Published: February 2013

We aimed to evaluate the association between the progressive stages of cervical neoplasia and DNA damage in 5-bp classical satellite DNA sequences from chromosome-1 in cervical epithelium and in peripheral blood lymphocytes using DNA breakage detection/fluorescence in situ hybridization (DBD-FISH). A hospital-based unmatched case-control study was conducted in 2011 with a sample of 30 women grouped according to disease stage and selected according to histological diagnosis; 10 with low-grade squamous intraepithelial lesions (LG-SIL), 10 with high-grade SIL (HG-SIL), and 10 with no cervical lesions, from the Unidad Medica de Alta Especialidad of The Mexican Social Security Institute, IMSS, Mexico. Specific chromosome damage levels in 5-bp classical satellite DNA sequences from chromosome-1 were evaluated in cervical epithelium and peripheral blood lymphocytes using the DBD-FISH technique. Whole-genome DNA hybridization was used as a reference for the level of damage. Results of Kruskal-Wallis test showed a significant increase according to neoplastic development in both tissues. The instability of 5-bp classical satellite DNA sequences from chromosome-1 was evidenced using chromosome-orientation FISH. In conclusion, we suggest that the progression to malignant transformation involves an increase in the instability of 5-bp classical satellite DNA sequences from chromosome-1.
Small Regulatory RNAs in the Control of Motility and Biofilm Formation in E. coli and Salmonella
Authors: Mika Franziska , Hengge Regine
Published: February 2013

Biofilm formation in Escherichia coli and other enteric bacteria involves the inverse regulation of the synthesis of flagella and biofilm matrix components such as amyloid curli fibres, cellulose, colanic acid and poly-N-acetylglucosamine (PGA). Physiologically, these processes reflect the transition from growth to stationary phase. At the molecular level, they are tightly controlled by various sigma factors competing for RNA polymerase, a series of transcription factors acting in hierarchical regulatory cascades and several nucleotide messengers, including cyclic-di-GMP. In addition, a surprisingly large number of small regulatory RNAs (sRNAs) have been shown to directly or indirectly modulate motility and/or biofilm formation. This review aims at giving an overview of these sRNA regulators and their impact in biofilm formation in E. coli and Salmonella. Special emphasis will be put on sRNAs, that have known targets such as the mRNAs of the flagellar master regulator FlhDC, the stationary phase sigma factor σS (RpoS) and the key biofilm regulator CsgD that have recently been shown to act as major hubs for regulation by multiple sRNAs.
Atypical Protein Phosphatases: Emerging Players in Cellular Signaling
Authors: Sadatomi Daichi , Tanimura Susumu , Ozaki Kei-ichi , Takeda Kohsuke
Published: February 2013

It has generally been considered that protein phosphatases have more diverse catalytic domain structures and mechanisms than protein kinases; however, gene annotation efforts following the human genome project appeared to have completed the whole array of protein phosphatases. Ser/Thr phosphatases are divided into three subfamilies that have different structures from each other, whereas Tyr phosphatases and dual-specificity phosphatases targeting Tyr, Ser and Thr belong to a single large family based on their common structural features. Several years of research have revealed, however, the existence of unexpected proteins, designated here as “atypical protein phosphatases”, that have structural and enzymatic features different from those of the known protein phosphatases and are involved in important biological processes. In this review, we focus on the identification and functional characterization of atypical protein phosphatases, represented by eyes absent (EYA), suppressor of T-cell receptor signaling (Sts) and phosphoglycerate mutase family member 5 (PGAM5) and discuss their biological significance in cellular signaling.
New Anti-Inflammatory Aromatic Components from Antrodia camphorata
Authors: Chen Yu-Chang , Chiu His-Lin , Chao Che-Yi , Lin Wen-Hsin , Chao Louis , Huang Guan-Jhong , Kuo Yueh-Hsiung
Published: February 2013

Three new benzenoids, 3-isopropenyl-2-methoxy-6-methyl-4,5-methylenedioxy- phenol (1), 2-hydroxy-4,4'-dimethoxy-3,3'-dimethyl-5,6,5',6'-bimethylenedioxybiphenyl (2), 4,4'-dihydroxy-3,3'-dimethoxy-2,2'-dimethyl-5,6,5',6'-bimethylenedioxybiphenyl (3), together with two known benzenoids, 2,3,6-trimethoxy-5-methylphenol (4) and 2,3-methylenedioxy- 4-methoxy-5-methylphenol (5), were isolated from Antrodia camphorata. Our results support that compounds 1–5 potently inhibited LPS (lipopolysaccharide)-induced nitric oxide (NO) production in a dose-dependent manner. The IC50 values of compounds 1, 3 and 5 were 1.8 ± 0.2, 18.8 ± 0.6 and 0.8 ± 0.3 μg/mL, respectively.
Incidence of Bacteriocins Produced by Food-Related Lactic Acid Bacteria Active towards Oral Pathogens
Authors: Zoumpopoulou Georgia , Pepelassi Eudoxie , Papaioannou William , Georgalaki Marina , Maragkoudakis Petros , Tarantilis Petros , Polissiou Moschos , Tsakalidou Effie , Papadimitriou Konstantinos
Published: February 2013

In the present study we investigated the incidence of bacteriocins produced by 236 lactic acid bacteria (LAB) food isolates against pathogenic or opportunistic pathogenic oral bacteria. This set of LAB contained several strains (≥17%) producing bacteriocins active against food-related bacteria. Interestingly only Streptococcus macedonicus ACA-DC 198 was able to inhibit the growth of Streptococcus oralis, Streptococcus sanguinis and Streptococcus gordonii, while Lactobacillus fermentum ACA-DC 179 and Lactobacillus plantarun ACA-DC 269 produced bacteriocins solely against Streptococcus oralis. Thus, the percentage of strains that were found to produce bacteriocins against oral bacteria was ~1.3%. The rarity of bacteriocins active against oral LAB pathogens produced by food-related LAB was unexpected given their close phylogenetic relationship. Nevertheless, when tested in inhibition assays, the potency of the bacteriocin(s) of S. macedonicus ACA-DC 198 against the three oral streptococci was high. Fourier-transform infrared spectroscopy combined with principal component analysis revealed that exposure of the target cells to the antimicrobial compounds caused major alterations of key cellular constituents. Our findings indicate that bacteriocins produced by food-related LAB against oral LAB may be rare, but deserve further investigation since, when discovered, they can be effective antimicrobials.
Irradiated Human Dermal Fibroblasts Are as Efficient as Mouse Fibroblasts as a Feeder Layer to Improve Human Epidermal Cell Culture Lifespan
Authors: Bisson Francis , Rochefort Éloise , Lavoie Amélie , Larouche Danielle , Zaniolo Karine , Simard-Bisson Carolyne , Damour Odile , Auger François , Guérin Sylvain , Germain Lucie
Published: February 2013

A fibroblast feeder layer is currently the best option for large scale expansion of autologous skin keratinocytes that are to be used for the treatment of severely burned patients. In a clinical context, using a human rather than a mouse feeder layer is desirable to reduce the risk of introducing animal antigens and unknown viruses. This study was designed to evaluate if irradiated human fibroblasts can be used in keratinocyte cultures without affecting their morphological and physiological properties. Keratinocytes were grown either with or without a feeder layer in serum-containing medium. Our results showed that keratinocytes grown either on an irradiated human feeder layer or irradiated 3T3 cells (i3T3) can be cultured for a comparable number of passages. The average epithelial cell size and morphology were also similar. On the other hand, keratinocytes grown without a feeder layer showed heavily bloated cells at early passages and stop proliferating after only a few passages. On the molecular aspect, the expression level of the transcription factor Sp1, a useful marker of keratinocytes lifespan, was maintained and stabilized for a high number of passages in keratinocytes grown with feeder layers whereas Sp1 expression dropped quickly without a feeder layer. Furthermore, gene profiling on microarrays identified potential target genes whose expression is differentially regulated in the absence or presence of an i3T3 feeder layer and which may contribute at preserving the growth characteristics of these cells. Irradiated human dermal fibroblasts therefore provide a good human feeder layer for an effective expansion of keratinocytes in vitro that are to be used for clinical purposes.
Characterization of Palytoxin Binding to HaCaT Cells Using a Monoclonal Anti-Palytoxin Antibody
Authors: Pelin Marco , Boscolo Sabrina , Poli Mark , Sosa Silvio , Tubaro Aurelia , Florio Chiara
Published: February 2013

Palytoxin (PLTX) is the reference compound for a group of potent marine biotoxins, for which the molecular target is Na+/K+-ATPase. Indeed, ouabain (OUA), a potent blocker of the pump, is used to inhibit some PLTX effects in vitro. However, in an effort to explain incomplete inhibition of PLTX cytotoxicity, some studies suggest the possibility of two different binding sites on Na+/K+-ATPase. Hence, this study was performed to characterize PLTX binding to intact HaCaT keratinocytes and to investigate the ability of OUA to compete for this binding. PLTX binding to HaCaT cells was demonstrated by immunocytochemical analysis after 10 min exposure. An anti-PLTX monoclonal antibody-based ELISA showed that the binding was saturable and reversible, with a Kd of 3 × 10−10 M. However, kinetic experiments revealed that PLTX binding dissociation was incomplete, suggesting an additional, OUA-insensitive, PLTX binding site. Competitive experiments suggested that OUA acts as a negative allosteric modulator against high PLTX concentrations (0.3–1.0 × 10−7 M) and possibly as a non-competitive antagonist against low PLTX concentrations (0.1–3.0 × 10−9 M). Antagonism was supported by PLTX cytotoxicity inhibition at OUA concentrations that displaced PLTX binding (1 × 10−5 M). However, this inhibition was incomplete, supporting the existence of both OUA-sensitive and -insensitive PLTX binding sites.
A Facile Synthesis of Deaza-Analogues of the Bisindole Marine Alkaloid Topsentin
Authors: Carbone Anna , Spanò Virginia , Parrino Barbara , Ciancimino Cristina , Attanasi Orazio , Favi Gianfranco
Published: February 2013

A series of substituted ethyl 1-[(tert-butoxycarbonyl)amino]-2-methyl-5- (1-methyl-1H-indol-3-yl)-4-[(1-methyl-1H-indol-3-yl)carbonyl]-1H-pyrrole-3-carboxylates were prepared in excellent yields (82-98%) by one-pot reactions between β-dicarbonyl compounds 12a–e and 1,2-diaza-1,3-diene (DD) 13. Derivatives 10a,c–e, deazaanalogues of the bis-indole alkaloid topsentin, screened by the National Cancer Institute (Bethesda, MD, USA) in the in vitro one dose primary anticancer assay against a panel of about 60 human tumor cell lines, showed no significant activity, with the exception of compound 9e, which showed moderate activity against the HOP-92 cell line of the non small cell lung cancer sub-panel and the SNB-75 cell line of the CNS sub-panel.
Identification of Alternaria alternata Mycotoxins by LC-SPE-NMR and Their Cytotoxic Effects to Soybean (Glycine max) Cell Suspension Culture
Authors: De Souza Gezimar , Mithöfer Axel , Daolio Cristina , Schneider Bernd , Rodrigues-Filho Edson
Published: February 2013

This present work describes the application of liquid chromatograpy-solid phase extraction-nuclear magnetic resonance spectroscopy to analyse Alternaria alternata crude extracts. Altenusin (1), alternariol (2), 3'-hydroxyalternariol monomethyl ether (3), and alternariol monomethyl ether (4), were separated and identified. High-resolution mass spectrometry confirmed the proposed structures. The cytotoxic effects of these compounds towards plants were determined using soybean (Glycine max) cell cultures as a model. EC50 values which range from 0.11 (±0.02) to 4.69 (±0.47) μM showed the high cytotoxicity of these compounds.
A New Hydroxychavicol Dimer from the Roots of Piper betle
Authors: Lin Chwan-Fwu , Hwang Tsong-Long , Chien Chun-Chien , Tu Huei-Yu , Lay Horng-Liang
Published: February 2013

A new hydroxychavicol dimer, 2-(g'-hydroxychavicol)-hydroxychavicol (1), was isolated from the roots of Piper betle Linn. along with five known compounds, hydroxychavicol (2), aristololactam A II (3), aristololactam B II (4), piperolactam A (5) and cepharadione A (6). The structures of these isolated compounds were elucidated by spectroscopic methods. Compounds 1 and 2 exhibited inhibitory effects on the generation of superoxide anion and the release of elastase by human neutrophils.
Lee et al., Inhibitory Effect and Mechanism of Antiproliferation of Isoatriplicolide Tiglate (PCAC) from Paulownia Coreana. Molecules 2012, 17, 5945-5951: A Note Regarding Paulownia coreana.
Authors: Wiart Christophe
Published: February 2013

I read with interest the article by Lee et al. entitled “Inhibitory Effect and Mechanism of Antiproliferation of Isoatriplicolide Tiglate (PCAC) from Paulownia Coreana” [1]. This article is quite interesting and the authors should be complimented for the significant amount of work they have done. The purpose of this letter is to call attention to the need for some clarification on the name of the plant described in this article. Lee et al. state: “Paulownia coreana has traditionally been used as the medicine and health food in the treatment of cancer and infectious diseases.” and elsewhere: “In fact, many cancer research studies have been conducted using traditional medicinal plants such as P. coreana.” [1].
The Significance of Matrix Metalloproteinases in Parasitic Infections Involving the Central Nervous System
Authors: Bruschi Fabrizio , Pinto Barbara
Published: February 2013

Matrix metalloproteinases (MMPs) represent a large family of over twenty different secreted or membrane-bound endopeptidases, involved in many physiological (embryogenesis, precursor or stem cell mobilization, tissue remodeling during wound healing, etc.), as well as pathological (inflammation, tumor progression and metastasis in cancer, vascular pathology, etc.) conditions. For a long time, MMPs were considered only for the ability to degrade extracellular matrix (ECM) molecules (e.g., collagen, laminin, fibronectin) and to release hidden epitopes from the ECM. In the last few years, it has been fully elucidated that these molecules have many other functions, mainly related to the immune response, in consideration of their effects on cytokines, hormones and chemokines. Among others, MMP-2 and MMP-9 are endopeptidases of the MMP family produced by neutrophils, macrophages and monocytes. When infection is associated with leukocyte influx into specific organs, immunopathology and collateral tissue damage may occur. In this review, the involvement of MMPs and, in particular, of gelatinases in both protozoan and helminth infections will be described. In cerebral malaria, for example, MMPs play a role in the pathogenesis of such diseases. Also, trypanosomosis and toxoplasmosis will be considered for protozoan infections, as well as neurocysticercosis and angiostrongyloidosis, as regards helminthiases. All these situations have in common the proteolytic action on the blood brain barrier, mediated by MMPs.
Photonic Crystal Biosensor Based on Optical Surface Waves
Authors: Konopsky Valery , Karakouz Tanya , Alieva Elena , Vicario Chiara , Sekatskii Sergey , Dietler Giovanni
Published: February 2013

A label-free biosensor device based on registration of photonic crystal surface waves is described. Angular interrogation of the optical surface wave resonance is used to detect changes in the thickness of an adsorbed layer, while an additional simultaneous detection of the critical angle of total internal reflection provides independent data of the liquid refractive index. The abilities of the device are demonstrated by measuring of biotin molecule binding to a streptavidin monolayer, and by measuring association and dissociation kinetics of immunoglobulin G proteins. Additionally, deposition of PSS / PAH polyelectrolytes is recorded in situ resulting calculation of PSS and PAH monolayer thicknesses separately.
On The Role of Natural Killer Cells in Neurodegenerative Diseases
Authors: Maghazachi Azzam
Published: February 2013

Natural killer (NK) cells exert important immunoregulatory functions by releasing several inflammatory molecules, such as IFN-γ and members of chemokines, which include CCL3/MIP-1α and CCL4/MIP-1β. These cells also express heptahelical receptors, which are coupled to heterotrimeric G proteins that guide them into inflamed and injured tissues. NK cells have been shown to recognize and destroy transformed cells and virally-infected cells, but their roles in neurodegenerative diseases have not been examined in detail. In this review, I will summarize the effects of NK cells in two neurodegenerative diseases, namely multiple sclerosis and globoid cell leukodystrophy. It is hoped that the knowledge obtained from these diseases may facilitate building rational protocols for treating these and other neurodegenerative or autoimmune diseases using NK cells and drugs that activate them as therapeutic tools.
Myeloid-Derived Suppressor Cells Suppress Antitumor Immune Responses through IDO Expression and Correlate with Lymph Node Metastasis in Patients with Breast Cancer
Authors: Yu Jinpu , Du Weijiao , Yan Fang , Wang Yue , Li Hui , Cao Shui , Yu Wenwen , Shen Chun , Liu Juntian , Ren Xiubao
Published: February 2013

Myeloid-derived suppressor cells (MDSCs) represent heterogeneous immunosuppressive cells in multiple cancer types and display potent immunosuppressive activity on T cells. We have shown the increased expression of IDO in breast cancer. Because IDO plays a pivotal role in immune tolerance via suppressing T cell function, the aim of this study was to investigate the expression of IDO in MDSCs in breast cancer and its role in MDSC-mediated inhibition of immune surveillance. The proportion of MDSCs with the phenotype of CD45+CD13+CD33+CD14−CD15− significantly increased in primary cancer tissues and patients’ peripheral blood. IDO expression was significantly upregulated in MDSCs isolated from fresh breast cancer tissues (fresh MDSCs [fMDSCs]), which correlated with increased infiltration of Foxp3+ regulatory T cells in tumors and lymph node metastasis in patients. fMDSCs inhibited IL-2 and anti-CD3/CD28 mAb-induced T cell amplification and Th1 polarization but stimulated apoptosis in T cells in an IDO-dependent manner. CD33+ progenitors isolated from healthy donors’ umbilical cord blood were cocultured with breast cancer cell line MDA-MB-231 cells to induce MDSCs. IDO expression was upregulated in induced MDSCs, which required phosphorylation of STAT3, but not STAT1. IDO was required for induced MDSCs’ immunosuppressive activity on T cells, which was blocked by IDO inhibitor 1-methyl-L-tryptophan or STAT3 antagonist JSI-124. Consistently, increased STAT3 phosphorylation level was found in fMDSCs. Together, our findings suggest that STAT3-dependent IDO expression mediates immunosuppressive effects of MDSCs in breast cancer. Thus, inhibition of MDSC-induced T cell suppression by blocking IDO may represent a previously unrecognized mechanism underlying immunotherapy for breast cancer.
KIR3DL2 Binds to HLA-B27 Dimers and Free H Chains More Strongly than Other HLA Class I and Promotes the Expansion of T Cells in Ankylosing Spondylitis
Authors: Wong-Baeza Isabel , Ridley Anna , Shaw Jackie , Hatano Hiroko , Rysnik Oliwia , McHugh Kirsty , Piper Christopher , Brackenbridge Simon , Fernandes Ricardo , Chan Anthoni , Bowness Paul , Kollnberger Simon
Published: February 2013

The human leukocyte Ag HLA-B27 (B27) is strongly associated with the spondyloarthritides. B27 can be expressed at the cell surface of APC as both classical β2-microglobulin–associated B27 and B27 free H chain forms (FHC), including disulfide-bonded H chain homodimers (termed B272). B27 FHC forms, but not classical B27, bind to KIR3DL2. HLA-A3, which is not associated with spondyloarthritis (SpA), is also a ligand for KIR3DL2. In this study, we show that B272 and B27 FHC bind more strongly to KIR3DL2 than other HLA-class I, including HLA-A3. B272 tetramers bound KIR3DL2-transfected cells more strongly than HLA-A3. KIR3DL2Fc bound to HLA-B27–transfected cells more strongly than to cells transfected with other HLA-class I. KIR3DL2Fc pulled down multimeric, dimeric, and monomeric FHC from HLA-B27–expressing cell lines. Binding to B272 and B27 FHC stimulated greater KIR3DL2 phosphorylation than HLA-A3. B272 and B27 FHC stimulated KIR3DL2CD3ε-transduced T cell IL-2 production to a greater extent than control HLA-class I. KIR3DL2 binding to B27 inhibited NK IFN-γ secretion and promoted greater survival of KIR3DL2+ CD4 T and NK cells than binding to other HLA-class I. KIR3DL2+ T cells from B27+ SpA patients proliferated more in response to Ag presented by syngeneic APC than the same T cell subset from healthy and disease controls. Our results suggest that expansion of KIR3DL2-expressing leukocytes observed in B27+ SpA may be explained by the stronger interaction of KIR3DL2 with B27 FHC.
Constitutively CD40–Activated B Cells Regulate CD8 T Cell Inflammatory Response by IL-10 Induction
Authors: Koni Pandelakis A. , Bolduc Anna , Takezaki Mayuko , Ametani Yutetsu , Huang Lei , Lee Jeffrey R. , Nutt Stephen L. , Kamanaka Masahito , Flavell Richard A. , Mellor Andrew L. , Tsubata Takeshi , Shimoda Michiko
Published: February 2013

B cells are exposed to high levels of CD40 ligand (CD40L, CD154) in chronic inflammatory diseases. In addition, B cells expressing both CD40 and CD40L have been identified in human diseases such as autoimmune diseases and lymphoma. However, how such constitutively CD40–activated B cells under inflammation may impact on T cell response remains unknown. Using a mouse model in which B cells express a CD40L transgene (CD40LTg) and receive autocrine CD40/CD40L signaling, we show that CD40LTg B cells stimulated memory-like CD4 and CD8 T cells to express IL-10. This IL-10 expression by CD8 T cells was dependent on IFN-I and programmed cell death protein 1, and was critical for CD8 T cells to counterregulate their overactivation. Furthermore, adoptive transfer of naive CD8 T cells in RAG-1−/− mice normally induces colitis in association with IL-17 and IFN-γ cytokine production. Using this model, we show that adoptive cotransfer of CD40LTg B cells, but not wild-type B cells, significantly reduced IL-17 response and regulated colitis in association with IL-10 induction in CD8 T cells. Thus, B cells expressing CD40L can be a therapeutic goal to regulate inflammatory CD8 T cell response by IL-10 induction.
Spontaneous Transmesenteric Hernia: A Rare Cause of Small Bowel Obstruction in an Adult
Authors: Chaudhary Poras , Rao Meenakshi , Kumar Alok , Khandelwal Sachin , Gupta Nikhil , Arora Moninder P.
Published: February 2013

The authors report a case of spontaneous transmesenteric hernia with strangulation in an adult. Transmesenteric hernia (TMH) is a rare cause of small bowel obstruction and is seldom diagnosed preoperatively, and most TMHs in adults are related to predisposing factors, such as previous surgery, abdominal trauma, and peritonitis. TMH are more likely to develop volvulus and strangulation or ischemia. A brief review of etiology, clinical features, diagnosis, and treatment is discussed.
Helicobacter pylori Infection Has No Impact on Manometric And pH-Metric Findings in Adolescents and Young Adults with Gastroesophageal Reflux and Antral Gastritis: Eradication Results to no Significant Clinical Improvement
Authors: Xinias Ioannis , Maris Theophanis , Mavroudi Antigoni , Panteliadis Christos , Vandenplas Yvan
Published: February 2013

The relationship between Helicobacter pylori (Hp) gastritis and gastroesophageal reflux disease (GERD) remains controversial. The aim was to investigate the association between Hp infection and gastroesophageal reflux (GER) and the impact of Hp eradication on esophageal acid exposure and motility in adolescents and young adults with Hp gastritis and GERD. Sixty-four patients with symptoms suggestive for GERD, of which 40 Hp-positive (group A) and 24 Hp-negative (group B), underwent endoscopy-biopsy, esophageal manometry and 24-hour pH-metry. All group A patients received eradication treatment and were re-evaluated six months later again with 24-hour pH-metry, esophageal manometry, endoscopy-biopsy and clinical assessment. At inclusion, there were no significant differences between the two groups regarding sex, age, grade of endoscopic esophagitis, manometric and pH-metry findings. All Hp-positive patients had an antral predominant gastritis. Eradication of Hp was successful in all patients, and gastritis and esophagitis were healed in all patients. The mean lower esophageal sphincter pressure (LESP) increased significantly from 11.25 mmHg before to 11.71 mmHg after eradication (P<0.05). A significant decrease in reflux index was observed (mean RI 6.02% before versus 4.96% after eradication (P<0.05). However clinical symptoms of GER improved not significantly after 6 months follow up. Conclusively, in children and young adults with GER symptoms and GERD, the presence or absence of Hp has no impact on manometric and pH-metric findings. Eradication of Hp infection results in increase in LESP with a consequent decrease in esophageal acid exposure but not significant clinical improvement.