bluuebunny/crossref_metadata_2025 huggingface dataset:
VOE: automated analysis of variant epitopes of SARS-CoV-2 for the development of diagnostic tests or vaccines for COVID-19
Authors: Lee Danusorn , Sangket Unitsa
Published: June 2024

Background

The development of serodiagnostic tests and vaccines for COVID-19 depends on the identification of epitopes from the SARS-CoV-2 genome. An epitope is the specific part of an antigen that is recognized by the immune system and can elicit an immune response. However, when the genetic variants contained in epitopes are used to develop rapid antigen tests (Ag-RDTs) and DNA or RNA vaccines, test sensitivity and vaccine efficacy can be low.

Methods

Here, we developed a “variant on epitope (VOE)” software, a new Python script for identifying variants located on an epitope. Variant analysis and sensitivity calculation for seven recommended epitopes were processed by VOE. Variants in 1,011 Omicron SRA reads from two variant databases (BCFtools and SARS-CoV-2-Freebayes) were processed by VOE.

Results

A variant with HIGH or MODERATE impact was found on all epitopes from both variant databases except the epitopes KLNDLCFTNV, RVQPTES, LKPFERD, and ITLCFTLKRK on the S gene and ORF7a gene. All epitope variants from the BCFtools and SARS-CoV-2 Freebayes variant databases showed about 100% sensitivity except epitopes APGQTGK and DSKVGGNYN on the S gene, which showed respective sensitivities of 28.4866% and 6.8249%, and 87.7349% and 71.1177%.

Conclusions

Therefore, the epitopes KLNDLCFTNV, RVQPTES, LKPFERD, and ITLCFTLKRK may be useful for the development of an epitope-based peptide vaccine and GGDGKMKD on the N gene may be useful for the development of serodiagnostic tests. Moreover, VOE can also be used to analyze other epitopes, and a new variant database for VOE may be further established when a new variant of SARS-CoV-2 emerges.
Socio-Economic, Socio-Personal and Demographic Profiling of KVK-Based Vermicompost Training Participants: Evidence from Bihar, India
Authors: Prakash Satya , Sikdar Samrat , K. Singh Ashok
Published: June 2024

Vermicompost is essentially a varied blend of decomposed farm waste, food waste, and worm castings, organically produced using different species of earthworms. This nutrient-dense organic fertilizer is gaining significant attention amid climate change concerns and the push for organic farming. Agricultural experts are increasingly advising farmers to transition from synthetic fertilizers to organic manures, prompting the need for training programs on vermicomposting to educate farmers about this valuable practice. This research aimed to examine the socioeconomic, demographic, and socio-personal characteristics of farmers who participated in three recent vermicomposting training sessions organized by three Krishi Vigyan Kendras (KVKs) in Bihar, India. This study adopted cross sectional survey design. The rationale behind this part of the project is to understand the various attributes of the training participants which could contribute in different ways to the adoption of vermicomposting. It also sought to reveal the status of those variables in relation to the adoption scenario amongst the current farming communities in those three districts. The study was carried out in three districts of Bihar—Samastipur, Muzaffarpur, and Madhubani—with a sample size of 150 farmers. Surveys were conducted in two blocks from each of these districts, selected purposefully. Data analysis was performed using statistical tools in SPSS to calculate the index for each individual farmer. A varied socio-demographic profile of the respondents was revealed who participated in the KVK-based vermicomposting training and it also provided a snapshot of the farming communities of the specific regions. This analysis concludes that the training sessions at three different KVKs attracted a diverse group of farm participants, characterized by varying demographic, socioeconomic, and socio-personal attributes. It is noteworthy that the majority of farmers who attended the vermicomposting training programs were small-scale and marginal farmers, with only a small percentage having high income levels. It is recommended to encourage stakeholder farmers to adopt this technology by providing training and support tailored to their socio-demographic profiles, as this could potentially increase the adoption rate among farmers.
The Influence of Financial Reporting Quality and Efficiency in Resources Utilization on Public Sector Financial Performance: Evidence from Tanzania
Authors: Lyezia Mwanjaa Said , Katamba Asha
Published: June 2024

This study intended to examine the influence of financial reporting quality and efficiency in resource utilization on public sector financial performance as the results of adoption of accrual based IPSAS in Tanzania. Guided with Stakeholders Theory, a cross sectional-survey design was applied in collecting data from 178 public sector entities by applying a drop and pick method. PLS-SEM was employed in determining the relationship between financial reporting quality, efficiency in resource utilization and public sector financial performance. The findings revealed that, efficiency in resource utilization has a positive and significant influence on financial performance in the public sector entities. The relationship between financial reporting quality and public sector financial performance was not significant. These findings imply that efficiency in public resources utilisation plays a major role in achieving objectives of IPSAS adoption, hence leading to improved public sector financial performance.
Organic Matter and Indigenous Vegetables in Sack under Waterlogged in Southwest Bangladesh
Authors: Nasrin Shamima , Mannan Md. Abdul , Sultana Sabiha , Sultana Rebaka , Kader Kamiliya , Parvin Nargis
Published: June 2024

A study on the prospect and profitability of indigenous vegetables (Kalmi, Helencha and Malancha Shak) was conducted in Shyamnagar Upazila of Satkhira district in waterlogged conditions from September 2020 to May 2021. In the study, three indigenous vegetables (Ipomoea aquatica, Enhydra fluctuans and Jussiaea repens) were tested with four levels of growing media viz., T0, control (no organic matter); T1, 75% organic matter+ 25 % soil; T2, 50 % organic matter +50% soil; T3, 25% organic matter+ 75% soil. Results show a significant difference among the treatments and different indigenous marshy leafy vegetables.
The maximum yield, gross and net income and BCR in all the vegetables were observed in T1. In the case of comparative analysis of different vegetables, the highest yield, gross and net income and BCR were also recorded from Helencha Shak and that was the lowest in Kalmi Shak.
Influence of Liquid Nano Urea Fertilizer on Growth and Yield of Summer Rice (Oryza sativa L.) under South Gujarat Conditions
Authors: S. D. Chudasama , V. P. Usadadia , A. R. Kaswala , K. K. Patel , B. J. Chaudhary , V. N. Shiyal
Published: June 2024

A field experiment was conducted during summer season for two consecutive years (2022-2023) at Navsari, Gujarat to study the effect of liquid Nano urea fertilizer on summer rice (Oryza sativa L.) under South Gujarat conditions. The experiment was laid out in randomized block design with three replications and twelve treatments comprising T1: 100 % RDN (Recommended dose of nitrogen) through urea (120 kg N ha-1), T2: 75 % RDN + Seedling root dip in Nano urea at transplanting (TP) (4 ml L-1), T3: 50 % RDN + Seedling root dip in Nano urea at TP (4 ml L-1), T4: 25 % RDN + Seedling root dip in Nano urea at TP (4 ml L-1), T5: 75 % RDN + Spray of Nano urea at tillering stage (4 ml L-1), T6: 50 % RDN + Spray of Nano urea at tillering stag (4 ml L-1), T7: 25 % RDN + Spray of Nano urea at tillering stage (4 ml L-1), T8: 75 % RDN + Spray of Nano urea at tillering and panicle initiation stage  (4 ml L-1), T9: 50 % RDN + Spray of Nano urea at tillering and panicle initiation stage (4 ml L-1), T10: 25 % RDN + Spray of Nano urea at tillering and panicle initiation stage (4 ml L-1), T11: Spray of Nano urea at tillering and panicle initiation stage (4 ml L-1) and T12: Seedling root dip in Nano urea at TP + Spray of Nano urea at tillering and panicle initiation stage (4 ml L-1). Application of 75 % RDN + Spray of Nano urea at tillering and panicle initiation stage (4 ml L-1) obtain significantly higher growth attributes viz., periodical plant height, number of tillers plant-1, dry matter accumulation plant-1, chlorophyll content and growth indices including leaf area index (LAI) at 60 and 90 DAS, crop growth rate (CGR), relative growth rate (RGR) and net assimilation rate (NAR) during 30-60 DAS, 60-90 DAS, and 90 DAS-Harvest. Similarly, significantly higher grain yield was produced under treatment T8 (4435 kg ha-1) which was 3.24% higher than 100% RDN through conventional urea.
DNA Barcoding of Economically Important Fruit Flies (Diptera: Tephritidae) from the Lower Gangetic Plains of Eastern India
Authors: Kar Oishik , Mukherjee Arka , Ghosh Debjani , Mukherjee Koustav , Pramanik Debdeep , Naskar Atanu , Banerjee Dhriti
Published: June 2024

The Lower Gangetic Plains are India's central horticultural crop production regions. Fruit flies (Diptera: Tephritidae) are a significant insect pest that significantly hinders the effective crop production of various commercially valuable fruit and vegetable crops. Therefore, rapid and precise species identification techniques are essential to controlling, managing, and quarantining these pests. Furthermore, reliably identifying fruit flies is exceedingly challenging due to their striking resemblances in morphological characters. In this work, we investigated the effectiveness of mitochondrial cytochrome c oxidase I (COI) gene sequences for identifying seven fruit fly species, involving only the genus Bactrocera from the lower Gangetic Plains in eastern India. The sequences of the studied species showed 99%–100% similarity with sequences from within and outside the country. COI barcodes were able to distinguish between species, with K2P intraspecific genetic divergences ranging from 0-1% and K2P interspecific genetic divergences ranging from 3.65-28.46%, thus maintaining a proper barcode gap. Phylogenetic analyses were performed, and the results showed moderate to high supported monophyly among species. Therefore, COI barcodes have proven a highly successful alternative for quickly identifying fruit flies. This is also the first account of molecular identification of the previously reported tephritid fruit flies infesting fruits and vegetables in eastern India's agriculturally important lower Gangetic Plains.
Near‐Infrared Fluorescent Silica/Porphyrin Hybrid Nanorings for In Vivo Cancer Imaging
Authors: Hayashi Koichiro , Nakamura Michihiro , Miki Hirokazu , Ozaki Shuji , Abe Masahiro , Matsumoto Toshio , Ishimura Kazunori
Published: May 2012

Ring‐shaped silica nanoparticles are synthesized with a high tetrakis(4‐carboxyphenyl)porphyrin (TCPP) content or silica/TCPP hybrid nanorings (HNRs) using a one‐pot sol‐gel reaction with a TCPP‐binding silica precursor for fluorescence imaging of tumor. The shape of the HNRs is a reflection of abundant ring‐shaped TCPP aggregates in the silica matrix. The HNRs are of a size that makes them susceptible to the enhanced permeability and retention effect. For comparison, the TCPP‐doped silica nanoparticles are synthesized using a conventional method. The nanoparticles are spherical in shape because little TCPP is contained in the silica matrix and are designated as TCPP‐containing silica nanospheres (NSs). The absorption bands of the HNRs shift by about 20 nm toward longer wavelengths compared with the TCPP bands. This redshift leads the excitation wavelength of the HNRs into the near‐infrared (NIR) region. Therefore, the HNRs are excited by NIR light to emit strong fluorescence, although the NSs emit no fluorescence. The PEGylated HNRs (PEG‐HNRs) are uncharged and possess a significantly longer blood circulation time than PEG‐NSs. The PEG‐HNRs accumulate in tumor through multiple factors including their size, uncharged surface, unique shape, and long circulation time in blood, resulting in the acquisition of clear images of tumor.
Light Extraction of Organic Light Emitting Diodes by Defective Hexagonal‐Close‐Packed Array
Authors: Koo Won Hoe , Youn Wooram , Zhu Peifen , Li Xiao‐Hang , Tansu Nelson , So Franky
Published: May 2012

Defective silica sphere arrays having locally hexagonal‐closed‐packed structure but lack of long range ordering were incorporated into organic light emitting diodes as grating to extract the waveguided light trapped in the indium tin oxide/organic layers and the glass substrate. Using these defective hexagonal‐closed‐packed gratings for light extraction, broad band lambertian emitters are obtained due to the periodicity broadening and the random orientation in the gratings, resulting in enhancements in current and power efficiencies by a factor of 1.7 and 1.9, respectively.
Endotoxin inhalation alters lung development in neonatal mice
Authors: Kulhankova Katarina , George Caroline L.S. , Kline Joel N. , Darling Melissa , Thorne Peter S.
Published: May 2012

Background

Childhood asthma is a significant public health problem. Epidemiologic evidence suggests an association between childhood asthma exacerbations and early life exposure to environmental endotoxin. Although the pathogenesis of endotoxin‐induced adult asthma is well studied, questions remain about the impact of environmental endotoxin on pulmonary responsiveness in early life.

Methods

We developed a murine model of neonatal/juvenile endotoxin exposures approximating those in young children and evaluated the lungs inflammatory and remodeling responses.

Results

Persistent lung inflammation induced by the inhalation of endotoxin in early life was demonstrated by the influx of inflammatory cells and pro‐inflammatory mediators to the airways and resulted in abnormal alveolarization.

Conclusions

Results of this study advance the understanding of the impact early life endotoxin inhalation has on the lower airways, and demonstrates the importance of an experimental design that approximates environmental exposures as they occur in young children. Am. J. Ind. Med. 55:1146–1158, 2012. © 2012 Wiley Periodicals, Inc.
Salmon allergen exposure, occupational asthma, and respiratory symptoms among salmon processing workers
Authors: Dahlman‐Höglund Anna , Renström Anne , Larsson Per H. , Elsayed Said , Andersson Eva
Published: May 2012

Background

This investigation was triggered by three cases of asthma—about 10% of the workforce—occurring in a salmon processing plant over a short period of time. The aim of the investigation was to characterize the work exposure of inhalable organic particles with personal measurements. Respiratory symptoms at work among workers were also assessed.

Methods

Exposures to airborne salmon allergen, airborne mold spores, and endotoxin in water and air were measured during work. To assess the Atlantic salmon (Salmo salar) Sal s 1 allergen exposure a polyclonal sandwich enzyme‐linked immunosorbent assay (ELISA) was developed. Current workers (n = 26) answered questionnaires and underwent allergy and lung function tests.

Results

Using the sensitive ELISA method (0.05 ng/ml), we found that workers were exposed to high levels of salmon major allergen at the filleting machine and at the filleting table. Airborne endotoxin levels were low, and mold levels were elevated. Only the three initial asthma cases had IgE to salmon. Of the other workers, 65% reported respiratory symptoms at work. These had lower pulmonary function than workers without such symptoms.

Conclusions

We developed a sensitive method to measure salmon antigen in air and found that filleting workers were most exposed. It is important to reduce aerosols by improving the ventilation system, machines and organization of work since respiratory symptoms at work among workers were common. Am. J. Ind. Med. 55:624–630, 2012. © 2012 Wiley Periodicals, Inc.
Brønsted‐Säure‐Aktivierung bei der übergangsmetallkatalysierten asymmetrischen Hydrierung N‐ungeschützter Imine, Enamine und N‐Heteroarene
Authors: Yu Zhengkun , Jin Weiwei , Jiang Quanbin
Published: May 2012

Die asymmetrische Hydrierung spielt in der organischen Synthese eine wichtige Rolle, aber erst in den letzten drei Jahren wurde die Hydrierung von schwierigen Substraten, wie N‐ungeschützten Iminen, Enaminen und N‐Heteroarenen (1H‐Indole, 1H‐Pyrrole, Pyridine, Chinoline und Chinoxaline) vermehrt untersucht. Wenn man die Wechselwirkungen einer Brønsted‐Säure mit einer Lewis‐Base betrachtet, könnten Brønsted‐Säuren als ideale Aktivatoren von CN‐Bindungen genutzt werden. Dieser Kurzaufsatz fasst aktuelle Entwicklungen bei der übergangsmetallkatalysierten, Brønsted‐Säure‐aktivierten asymmetrischen Hydrierung dieser anspruchsvollen Substrate zusammen und präsentiert damit eine vielversprechende Substrataktivierungsstrategie für Umwandlungen unter Beteiligung von CN‐Bindungen.
Preparation and properties of poly(dimethyl siloxane)–colloidal silica/functionalized colloidal silica nanocomposites
Authors: Dinkar Sumi , Dhanabalan A. , Thimmappa B. H. S.
Published: May 2012

Aqueous spherical colloidal silica (CS) particles with a diameter of 15 ± 5 nm were modified with three different types of monofunctional silane coupling agents to prepare functionalized colloidal silica (FCS) particles. The effects of the surface chemistry of the FCS were studied as a function of the CS/FCS loading in the poly(dimethyl siloxane) (PDMS) polymer. The prepared PDMS–CS/FCS composites were investigated for their physical properties both in the cured and uncured states. The extent of filler–filler and filler–polymer interactions was found to vary with the type of functionalizing agent used to treat the surface of the CS. The filler–filler interaction appeared to be predominant in the PDMS–CS composites, and improved filler–polymer interaction was indicated in the case of the PDMS–FCS composites. The composites containing CS treated with methyltrimethoxysilane exhibited relatively better optical and mechanical properties compared to the other PDMS–FCS composites. This study highlighted the importance of judiciously choosing functionalizing agents to achieve PDMS–FCS composites with predetermined optical and mechanical properties. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Nanocrystalline‐cellulose‐reinforced poly(vinylidenefluoride‐co‐hexafluoropropylene) nanocomposite films as a separator for lithium ion batteries
Authors: Lalia Boor Singh , Samad Yarjan Abdul , Hashaikeh Raed
Published: May 2012

Nanocrystalline cellulose (NCC) was synthesized by the facile acid hydrolysis of Kim Wipes tissue papers and characterized with atomic force microscopy (AFM) and X‐ray diffraction (XRD). AFM images confirmed the nanosize of the cellulose nanocrystals, and XRD data revealed the high crystallinity. NCC‐reinforced poly(vinylidene fluoride‐co‐hexafluoropropylene) (PH) nanocomposite films were fabricated via an electrospinning method. Different concentrations of NCC in the PH matrix were studied. The effects of the NCC content on the tensile modulus, the variation of tensile modulus with temperature, and the thermal properties of the fabricated nanocomposite films were investigated. It was found that PH + 2 wt % NCC was the optimum composition of the nanocomposite. The addition of 2 wt % NCC in the PH films led to a 75% improvement in the tensile modulus. Dynamic mechanical analysis of the PH nanocomposite films with 2 wt % NCC exhibited high values of tensile modulus in the 30–150°C temperature range. High concentrations of NCC led to decreases in the tensile modulus and thermal properties of the separator. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2012
Effect of clay modification on the morphology and the mechanical/physical properties of ABS/PMMA blends
Authors: Nazari Tayebe , Garmabi Hamid , Arefazar Ahmad
Published: May 2012

The effect of three types of organoclays on the morphology and mechanical properties of lower critical solution temperature‐type poly(acrylonitrile‐butadiene‐styrene)/poly(methyl methacrylate) (ABS/PMMA) blends was investigated. Polymers were melt‐compounded with 2 and 4 wt % of clays using a twin‐screw extruder. X‐ray scattering and transmission electron microscopy revealed that the intercalation of the nanoclay in the hybrid nanocomposite was more affected by the polarity of the organoclay. Although the morphology of the blends varied by PMMA content, scanning electron microscopy showed smaller PMMA domains for the hybrid systems containing clay particles. Although good dispersion of the nanoclay through the ABS matrix and at the blend interface led to enhancement of tensile strength, the increment of the stiffness was more noticeable for nanocomposites including less polar organoclay. Well‐dispersed clay platelets increased the glass transition temperature. In addition, nanoscratching analysis illustrated an improvement in scratch resistance of ABS because of the presence of PMMA and organoclay. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Electrospinning of thermoplastic polyurethane microfibers and nanofibers from polymer solution and melt
Authors: Dasdemir Mehmet , Topalbekiroglu Mehmet , Demir Ali
Published: May 2012

Electrospinning technique was used to produce ultrafine fibers from thermoplastic polyurethane (TPU). A direct comparison between melt and solution electrospinning of TPU was provided for the evaluation of process–structure relationship. It was found that the deposition rate of melt electrospinning (0.6 g h−1) is four times higher than that of solution electrospinning (0.125 g h−1) for TPU under the same processing condition. However, the average fiber diameters of solution electrospun TPUs (220–280 nm) were much lower than those of melt electrospun TPUs (4–8 μm). The effect of processing variables including collection distance and electric field strength on the electrospun fiber diameter and morphology was also studied. The findings indicate that increasing the electric field strength yielded more electrical forces acting on polymer jet and resulted in a decrease in fiber diameter as a result of more fiber drawing in both solution and melt electrospun fibers. It was also demonstrated that increasing the collection distance led to an improvement in the solidification of melt electrospun fibers and thus less fused fibers were obtained. Finally, a close investigation of fiber structures revealed that melt electrospun TPU fibers had smooth surface, whereas solution electrospun TPU fibers showed high intensity of cracks on the fiber surface. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Effects of accelerated aging and compatibilizers on the mechanical and morphological properties of polypropylene and poly(acrylonitrile‐butadiene‐styrene) blends
Authors: Lee Yun Kyun , Lee Jae Bok , Park Dong Hyup , Kim Woo Nyon
Published: May 2012

The effects of maleic anhydride‐grafted styrene‐ethylene‐butylene‐styrene copolymer (SEBS‐g‐MAH) on the mechanical and morphological properties of polypropylene (PP) and poly(acrylonitrile‐butadiene‐styrene) (ABS) blends were investigated. Based on mechanical properties, including impact and tensile strengths, the PP/ABS (70/30) blends containing SEBS‐g‐MAH showed improved impact strength with minimal loss of tensile strength. As determined from morphological studies of the PP/ABS blends, addition of SEBS‐g‐MAH decreased PP/ABS blend droplet size more than the addition of SEBS. Additionally, the effects of SEBS‐g‐MAH and SEBS on the mechanical and morphological properties of the PP/ABS (70/30) blends were investigated during accelerated aging in an oven at 90°C for 72 h (one cycle). The impact strength of the PP/ABS (70/30) blends with SEBS‐g‐MAH (7 phr) decreased less than 10% after five cycles, but blends with SEBS (7 phr) and blends without compatibilizer decreased as much as 37%. The tensile strengths of the PP/ABS (70/30) blends after accelerated aging indicated a trend similar to that of the impact strength. The morphological studies indicated no significant changes in the PP/ABS (70/30) blends with SEBS‐g‐MAH; however, many cavities and damages were observed in the blend with SEBS. The above results suggest that SEBS‐g‐MAH acts as an impact modifier and as a good compatibilizer in the PP/ABS (70/30) blends. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Experimental characterization of a curing thermoset epoxy‐anhydride system—Isothermal and nonisothermal cure kinetics
Authors: Huang Xiaosong , Patham Bhaskar
Published: May 2012

This work describes in detail the kinetic model for the cure of an epoxy‐anhydride thermoset matrix resin system. The cure kinetics in both nonisothermal and isothermal modes has been characterized using differential scanning calorimetry. The Sestak–Berggren two‐parameter autocatalytic model was used to describe the nonisothermal cure behavior of the resin satisfactorily. The isothermal cure data was fitted with Kamal's four‐parameter autocatalytic model, coupled with a diffusion factor. These characterization data will form material property inputs for a multiscale modeling framework for the estimation of cure‐induced residual stresses in thick thermoset matrix composites. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Synthesis, characterization, and swelling behavior of new pH‐sensitive hydrogels derived from copolymers of 2‐hydroxyethyl methacrylate and 2‐(diisopropylamino)ethylmethacrylate
Authors: Faccia Paula A. , Amalvy Javier I.
Published: May 2012

The aim of this work was to synthesize and to characterize new pH‐sensitive hydrogels that can be used in the controlled release of drugs, useful for dermal treatments or ophthalmology's therapies. Copolymers containing 2‐hydroxyethyl methacrylate (HEMA) with different amounts of 2‐(diisopropylamino)ethyl methacrylate (DPA) (10 and 30 wt %) and different amounts of crosslinker agent, ethylene glycol dimethacrylate (EGDMA) (1 and 3 wt %) were prepared by bulk photo‐polymerization. The copolymers were fully characterized by using Fourier‐transform infrared (FTIR) spectra, differential scanning calorimetry, thermogravimetric analysis, UV–visible spectroscopy, and measuring water content and dynamic swelling degree. The results show that modifications in the amount of DPA and/or crosslinker in the hydrogel produce variations in the thermal properties. When adding of DPA, we observed an increase in the thermal stability and decomposition temperature, as well as a change in the mechanism of decomposition. Also a decrease in the glass transition temperature was observed with regard to the value for pure pHEMA, by the addition of DPA. The water content of the hydrogels depends on the DPA content and it is inversely proportional to both the pH value and the crosslinking degree. Pure poly‐HEMA films did not show important changes over the pH range studied in this work. The dynamic swelling curves show the overshooting effect associated with the incorporation of DPA, the pH of the solution, and the crosslinking density. On the other hand, no important variations in the optical properties were observed. The synthesized hydrogels are useful as a drug delivery pH‐sensitive matrix. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
In situ crosslinkable sulfonated polyaromatic ionomers for the polyelectrolyte used in proton exchange membrane fuel cell
Authors: Wang S. J. , Chen Y. , Xiao M. , Meng Y. Z.
Published: May 2012

Two series of sulfonated poly(arylene ether nitrile ketone) ionomers containing potential crosslinkable nitrile groups were synthesized in high yield by direct aromatic nucleophilic polycondensation of 1,4‐bis‐(4‐hydroxyphenyl)‐2,3‐dicyano ‐naphthalene (3) with different molar ratio of disodium 5,5′‐carbonyl‐bis‐(2‐fluorobenzene‐sulfonate) (4) to 5,5′‐carbonyl‐bis‐(2‐fluorobenzene) (5) or 4,4‐biphenol (7). Subsequently, the sulfonated polymeric ionomers were in situ crosslinked when cast into membranes from solution at 180°C under nitrogen protection. The structure of the synthesized polymers was characterized by 1H‐nuclear magnetic resonance (NMR), Fourier‐transform infrared spectra, and elemental analysis. Comparing with the original polymeric membranes, the crosslinked membranes showed much better thermal and hydrolytic stabilities and superior mechanical properties as well as much lower swelling behavior, which were even better than Nafion 117 membrane. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Copolymer‐induced silk‐based hydrogel with porous and nanofibrous structure
Authors: Zhong Tianyi , Xie Zonggang , Deng Chunmin , Chen Mei , Gao Yanfei , Zuo Baoqi
Published: May 2012

A novel physical blend method was developed to accelerate the self‐assembly process of silk fibroin (SF) solution into porous and nanofibrous hydrogel by temperature‐sensitive copolymer. Silk‐based hydrogel was firstly achieved through blending SF solution with copolymer aqueous solution and then removed the copolymer from blend solution by heat treatment (50°C) after 24 h hydrogelation. Copolymer molecules would interact with SF molecules resulting in reduction of copolymer micelles, which further affect the hydrogelation of SF solutions. Copolymers could be separated from blend solution by heat treatment under an acceptable temperature (50°C), especially the copolymer2. Fourier transform infrared (FTIR) and X‐ray diffraction showed the blending of copolymer significantly accelerated the self‐assembly of SF into physically crosslinked β‐sheet crystals at room temperature which led to the sol‐gel transition. Results from DTA and X‐ray diffraction showed that the effect of copolymer on crystalline structure of SF in silk‐based hydrogel was very weak. SF molecules transformed from distributed globular nanoparticles to nanofilaments clustered during hydrogelation, resulting in the porous and nanofibrous structure of silk‐based hydrogel. Furthermore, silk‐based hydrogel was prepared in aqueous solution avoiding organic solvents and harsh processing conditions, suggesting that this silk‐based hydrogel could be a potential candidate scaffold for biomedical applications. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Variation of lexan polycarbonate properties by electron beam
Authors: Hareesh K. , Ranganathaiah C. , Ramya P. , Bhargavi R. , Nair Geetha G. , Sangappa  , Sanjeev Ganesh
Published: May 2012

The modifications in microstructural, optical, and photoluminescence properties of the Lexan polycarbonate (bisphenol‐A‐polycarbonate) films exposed to different electron doses have been studied using UV–vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), positron annihilation lifetime spectroscopy, photoluminescence spectroscopy, and scanning electron microscopy (SEM). The obtained UV–vis spectroscopy results showed decrease in optical energy gap, optical activation energy, and increase in number of carbon atoms per cluster with increase in electron dose. The chemical changes in electron irradiated polymers due to chain scission and reconstruction have been observed from FTIR spectroscopy. The correlation of positron lifetime study with optical measurement is obtained, and electron irradiation‐induced microstructural modifications within the polymer is understood. SEM result shows the degradation of Lexan polymer after electron irradiation. The mechanical properties and average molecular weight of Lexan decrease after irradiation, whereas average number of chain scissions per original polymer molecule increases. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Solid‐state hydrolysis of postconsumer polyethylene terephthalate after plasma treatment
Authors: Mancini Sandro Donnini , Nogueira Alex Rodrigues , Rangel Elidiane Cipriano , da Cruz Nilson Cristino
Published: May 2012

Plasma treatments were applied on the surface of postconsumer polyethylene terephthalate (PET) bottles to increase their wettability and hasten the subsequent hydrolysis process. Sixty‐four treatments were tested by varying plasma composition (oxygen and air), power (25–130 W), pressure (50–200 mTorr), and time (1 and 5 min). The best treatment was the one applied in air plasma at 130 W and 50 mTorr for 5 min, as it provided the lowest contact angle, 9.4°. Samples of PET before and after the optimized plasma condition were subjected to hydrolysis at 205°C. Although the treatment changed only a thin surface layer, its influence was evident up to relatively high conversion rates, as the treated samples presented more than 40% higher conversion rates than the untreated ones after 2 h of reaction. Infrared spectroscopy showed that the terephthalic acid obtained from 99% of depolymerization was similar to the commercial product used in PET synthesis. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Synthesis of epoxy resin–silica nanocomposites provided from perhydropolysilazane as a curing reagent and the precursor of silica domain
Authors: Saito Reiko , Fujii Yosuke , Kumagai Tohru
Published: May 2012

Epoxy resin–silica nanocomposites with spherical silica domains with 29.0 nm in diameter in an epoxy resin matrix were synthesized from Bisphenol‐A type epoxide monomer, 2,2‐bis(4‐glycidyloxyphenyl)propane (DGEBA), and perhydropolysilazane (PHPS, [Si2NH]n). The volume fraction of silica domain in the composite varied from 5.4 to 37.8 vol % by varying the feed ratio of PHPS to the epoxide monomer. The reaction mechanism of epoxy group and PHPS was investigated by using glycidyl methacrylate as a model compound of the epoxy monomer by 1H‐nucular magnetic resonance and Fourier transform infrared spectrometry. Ammonia gas provided by the decomposition of PHPS with moisture converted PHPS to silica and cured the epoxy monomer. The curing of epoxy monomer preferably proceeded than the conversion of silica. The addition of 1,4‐diaminobutane drastically accelerated the rate of curing; white and hard epoxy resin–silica nanocomposites were obtained. The good thermal stability of the composite prepared with DGEBA/PHPS/1,4‐diaminobutane was observed by thermogravimetric analysis. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
A clinical and serologic comparison of African American and Caucasian patients with systemic sclerosis
Authors: Steen Virginia , Domsic Robyn T. , Lucas Mary , Fertig Noreen , Medsger Thomas A.
Published: May 2012

Objective

Epidemiology studies suggest that systemic sclerosis (SSc) is more common, occurs at a younger age, and is more severe in African Americans than Caucasians. However, the scleroderma autoantibody profile is very different between these 2 ethnic groups. This study was undertaken to examine the demographic and disease features, frequency and severity of internal organ system involvement, and survival in African American patients compared to Caucasian patients with SSc, giving particular attention to their serum autoantibody profiles.

Methods

Demographic features, clinical characteristics, autoantibody profile, organ involvement, and survival were studied in consecutive African American and Caucasian patients with SSc whose visits were recorded between 1972 and 2007 as part of the Pittsburgh Scleroderma Database. The Medsger Severity Score for SSc was used to determine the severity of disease.

Results

African American patients were more likely to have anti–topoisomerase I (anti–topo I), anti–U1 RNP, and anti–U3 RNP autoantibodies. In comparing African American and Caucasian patients with these antibodies, pulmonary fibrosis was found to be more frequent and more severe, and the rate of survival was decreased, in African American patients with anti–topo I antibodies compared to Caucasian patients with anti–topo I. Pulmonary fibrosis was also more severe in the anti–U1 RNP–positive patients, but this was not associated with a difference in survival between African Americans and Caucasians. Anti–U3 RNP was associated with more severe gastrointestinal involvement in African Americans compared to Caucasians.

Conclusion

African Americans with SSc have more severe disease complications compared to Caucasians with SSc, and this is associated with both the type of autoantibody present and the severity of interstitial lung disease. Thus, it is hoped that early aggressive intervention in African Americans with interstitial lung disease will improve outcomes.
Effect of intensive lipid‐lowering therapy on cardiovascular outcome in patients with and those without inflammatory joint disease
Authors: Semb Anne Grete , Kvien Tore K. , DeMicco David A. , Fayyad Rana , Wun Chuan‐Chuan , LaRosa John C. , Betteridge John , Pedersen Terje R. , Holme Ingar
Published: May 2012

Objective

To examine the effect of intensive lipid‐lowering therapy on a composite cardiovascular outcome (cardiovascular disease [CVD]), consisting of mortality and morbidity end points, in patients with inflammatory joint disease (rheumatoid arthritis [RA], ankylosing spondylitis [AS], or psoriatic arthritis [PsA]) by post hoc analysis of 2 prospective trials of statins with a secondary end point of CVD outcome (the Treating to New Targets [TNT] and Incremental Decrease in End Points Through Aggressive Lipid Lowering [IDEAL] studies).

Methods

Of the 18,889 patients participating in the 2 trials, 199 had RA, 46 had AS, and 35 had PsA. Lipid‐lowering therapy consisted of an intensive regimen of atorvastatin 80 mg or a conventional/low‐dose regimen of atorvastatin 10 mg or simvastatin 20–40 mg. The median duration of followup was nearly 5 years. Changes in lipid levels were examined by analyses of covariance. The effect on CVD was examined by Cox regression analyses, and heterogeneity tests were performed.

Results

Patients with RA and those with AS had lower baseline cholesterol levels than patients without inflammatory joint disease (least squares mean ± SEM 180.7 ± 2.3 mg/dl and 176.5 ± 4.7 mg/dl, respectively, versus 185.6 ± 0.2 mg/dl; P = 0.03 and P = 0.05, respectively). Statin treatment led to a comparable decrease in lipid levels and a 20% reduction in overall risk of CVD in both patients with and those without inflammatory joint disease.

Conclusion

Our findings indicate that patients with and those without inflammatory joint disease experience comparable lipid‐lowering effects and CVD risk reduction after intensive treatment with statins.
Enhanced suppressor of cytokine signaling 3 in arthritic cartilage dysregulates human chondrocyte function
Authors: van de Loo Fons A. J. , Veenbergen Sharon , van den Brand Ben , Bennink Miranda B. , Blaney‐Davidson Esmeralda , Arntz Onno J. , van Beuningen Henk M. , van der Kraan Peter M. , van den Berg Wim B.
Published: May 2012

Objective

To determine the expression of suppressor of cytokine signaling 3 (SOCS‐3) in human articular chondrocytes and its functional consequences.

Methods

Chondrocytes were isolated from the cartilage of patients with osteoarthritis (OA), patients with rheumatoid arthritis (RA), and trauma patients and from the healthy cartilage of patients with a femoral neck fracture. The human chondrocyte cell line G6 and primary bovine chondrocytes were used in validation experiments. SOCS‐3 messenger RNA (mRNA) expression was measured by quantitative polymerase chain reaction, and SOCS‐3 protein levels were determined by Western blotting and immunohistochemical analysis. To ascertain the role of SOCS‐3 in the chondrocyte response to interleukin‐1β (IL‐1β) or lipopolysaccharide (LPS), the expression of SOCS3 was either reduced by small interfering RNA or enhanced by viral transduction.

Results

The expression of SOCS‐3 mRNA (but not that of SOCS‐1 mRNA) was significantly enhanced in chondrocytes obtained from OA cartilage (mean ± SD ΔCt 3.4 ± 1.0) and RA cartilage (ΔCt 3.4 ± 1.4) compared with cartilage obtained from patients with femoral neck fracture (ΔCt 5.3 ± 1.2). The expression of SOCS3 correlated significantly with that of other genes known to be expressed in arthritic chondrocytes, such as MMP13 (r = 0.743), ADAMTS4 (r = 0.779), and ADAMTS5 (r = 0.647), and an inverse relationship was observed with COL2A1 (r = −0.561). Up‐regulation of SOCS‐3 by IL‐1 in G6 chondrocytes and its spontaneous expression in OA chondrocytes were reduced by mithramycin, a specific inhibitor of transcription factor Sp‐1. Overexpression of SOCS‐3 in bovine chondrocytes reduced IL‐1– and LPS‐induced nitric oxide production and insulin‐like growth factor 1–induced proteoglycan synthesis. Interestingly, a similar impairment of function was observed in OA chondrocytes, which was partially restored by SOCS‐3 gene knockdown.

Conclusion

This study demonstrated that both SOCS‐3 mRNA and SOCS‐3 protein are expressed in human arthritic chondrocytes and affect cellular responses involved in cartilage pathology.
Gremlin 1, Frizzled‐related protein, and Dkk‐1 are key regulators of human articular cartilage homeostasis
Authors: Leijten J. C. H. , Emons J. , Sticht C. , van Gool S. , Decker E. , Uitterlinden A. , Rappold G. , Hofman A. , Rivadeneira F. , Scherjon S. , Wit J. M. , van Meurs J. , van Blitterswijk C. A. , Karperien M.
Published: May 2012

Objective

The development of osteoarthritis (OA) may be caused by activation of hypertrophic differentiation of articular chondrocytes. Healthy articular cartilage is highly resistant to hypertrophic differentiation, in contrast to other hyaline cartilage subtypes, such as growth plate cartilage. The purpose of this study was to elucidate the molecular mechanism responsible for the difference in the propensity of human articular cartilage and growth plate cartilage to undergo hypertrophic differentiation.

Methods

Whole‐genome gene‐expression microarray analysis of healthy human growth plate and articular cartilage derived from the same adolescent donors was performed. Candidate genes, which were enriched in the articular cartilage, were validated at the messenger RNA (mRNA) and protein levels and examined for their potential to inhibit hypertrophic differentiation in two models. In addition, we studied a possible genetic association with OA.

Results

Pathway analysis demonstrated decreased Wnt signaling in articular cartilage as compared to growth plate cartilage. This was at least partly due to increased expression of the bone morphogenetic protein and Wnt antagonists Gremlin 1, Frizzled‐related protein (FRP), and Dkk‐1 at the mRNA and protein levels in articular cartilage. Supplementation of these proteins diminished terminal hypertrophic differentiation without affecting chondrogenesis in long‐bone explant cultures and chondrogenically differentiating human mesenchymal stem cells. Additionally, we found that single‐nucleotide polymorphism rs12593365, which is located in a genomic control region of GREM1, was significantly associated with a 20% reduced risk of radiographic hip OA in 2 population‐based cohorts.

Conclusion

Taken together, our study identified Gremlin 1, FRP, and Dkk‐1 as natural brakes on hypertrophic differentiation in articular cartilage. As hypertrophic differentiation of articular cartilage may contribute to the development of OA, our findings may open new avenues for therapeutic intervention.
Natural antibody to apoptotic cell membranes inhibits the proinflammatory properties of lupus autoantibody immune complexes
Authors: Vas Jaya , Grönwall Caroline , Marshak‐Rothstein Ann , Silverman Gregg J.
Published: May 2012

Objective

Naturally arising IgM antibodies (NAb) to apoptotic cell (AC) determinants are present from birth and can be further induced by AC challenge. In systemic lupus erythematosus, lower anti‐AC NAb levels have been associated with higher disease activity. We have recently shown that a prototypical AC‐specific IgM NAb can suppress proinflammatory responses to purified agonists of Toll‐like receptors and block the in vivo induction of IgG immune complex (IC)–induced arthritis. Nuclear antigens, which activate dendritic cells (DCs), form complexes with IgG autoantibody, and these have been implicated in the pathogenesis of autoimmune disease. In this study, we sought to investigate potential roles of such NAb for regulating IC‐mediated activation of DCs, which is believed to be involved in disease initiation and perpetuation.

Methods

Bone marrow–derived myeloid DCs were stimulated with ICs composed of IgG autoantibody and chromatin or IgG autoantibody and RNA. Outcome was evaluated according to the production of inflammatory cytokines, as determined by enzyme‐linked immunosorbent assay, and the expression of costimulatory molecules (markers of DC activation), as determined by flow cytometry. MAPK activation was evaluated by phospho‐flow analysis and immunofluorescence microscopy.

Results

IgM anti‐AC NAb dose‐dependently suppressed the production of DNA IC– and RNA IC–induced interleukin‐6 and DNA IC–induced tumor necrosis factor α, as well as the RNA IC–induced up‐regulation of CD86 and CD40 on DCs. IgM NAb–mediated inhibition was associated with suppression of IC‐mediated p38 MAPK activation and nuclear localization.

Conclusion

We demonstrated a direct in vitro inhibitory effect of IgM NAb on inflammatory responses induced by IgG–nucleic acid ICs. These findings contribute to emerging evidence that regulatory NAb to AC determinants may oppose the influence of pathogenic lupus autoantibody ICs and thereby play roles in the maintenance of immune homeostasis.
Inhibiting HLA–B27 homodimer–driven immune cell inflammation in spondylarthritis
Authors: Payeli Sravan K. , Kollnberger Simon , Marroquin Belaunzaran Osiris , Thiel Markus , McHugh Kirsty , Giles Joanna , Shaw Jacqueline , Kleber Sascha , Ridley Anna , Wong‐Baeza Isabel , Keidel Sarah , Kuroki Kimiko , Maenaka Katsumi , Wadle Andreas , Renner Christoph , Bowness Paul
Published: May 2012

Objective

Spondylarthritides (SpA), including ankylosing spondylitis (AS), are common inflammatory rheumatic diseases that are strongly associated with positivity for the HLA class I allotype B27. HLA–B27 normally forms complexes with β2‐microglobulin (β2m) and peptide to form heterotrimers. However, an unusual characteristic of HLA–B27 is its ability to form β2m‐free heavy chain homodimers (HLA–B272), which, unlike classic HLA–B27, bind to killer cell immunoglobulin‐like receptor 3DL2 (KIR‐3DL2). Binding of HLA–B272 to KIR‐3DL2–positive CD4+ T and natural killer (NK) cells stimulates cell survival and modulates cytokine production. This study was undertaken to produce an antibody to HLA–B272 in order to confirm its expression in SpA and to inhibit its proinflammatory properties.

Methods

We generated monoclonal antibodies by screening a human phage display library positively against B272 and negatively against B27 heterotrimers. Specificity was tested by enzyme‐linked immunosorbent assay (ELISA), surface plasmon resonance (SPR) assay, and fluorescence‐activated cell sorting (FACS) analysis of B272‐expressing cell lines and peripheral blood mononuclear cells (PBMCs) and synovial fluid mononuclear cells (SFMCs) from patients with SpA. Functional inhibition of KIR‐3DL2–B272 interactions was tested using cell lines and PBMCs from patients with SpA.

Results

Monoclonal antibody HD6 specifically recognized recombinant HLA–B272 by ELISA and by SPR assay. HD6 bound to cell lines expressing B272. FACS revealed binding of HD6 to PBMCs and SFMCs from patients with AS but not from controls. HD6 inhibited both the binding of HLA–B272 to KIR‐3DL2 and the survival and proliferation of KIR‐3DL2–positive NK cells. Finally, HD6 inhibited production of the proinflammatory disease–associated cytokine interleukin‐17 by PBMCs from patients with AS.

Conclusion

These results demonstrate that antibody HD6 has potential for use in both the investigation and the treatment of AS and other B27‐associated spondylarthritides.