bluuebunny/crossref_metadata_2025 huggingface dataset:
Transplantation of chondrocytes seeded on collagen‐based scaffold in cartilage defects in rabbits
Authors: De Franceschi Luciana , Grigolo Brunella , Roseti Livia , Facchini Andrea , Fini Milena , Giavaresi Gianluca , Tschon Matilde , Giardino Roberto
Published: August 2005

Recent success in tissue engineering by restoring cartilage defects by transplanting autologous chondrocyte cells on a three‐dimensional scaffold has prompted the improvement of this therapeutic strategy. Here we describe a new approach investigating the healing of rabbit cartilage by means of autologous chondrocytes seeded on a biomaterial made of an equine collagen type I‐based scaffold. Full‐thickness defects were created bilaterally in the weight‐bearing surface of the medial femoral condyle of both femora of New Zealand male rabbits. The wounds were then repaired by using both chondrocytes seeded on the biomaterial and biomaterial alone. Controls were similarly treated but received either no treatment or implants of the delivery substance. Histological examination of the reconstructed tissues at 1, 3, 6, and 12 months after transplantation showed that at 1 and 3 months there was no formation of reconstructed tissue in any of the groups evaluated; after 6 months there was evidence of a newly regenerated tissue with some fibrocartilaginous features only in the group treated with biomaterial‐seeded cells, and at 12 months a more organized tissue was evident in the same group. With regards to the group transplanted with biomaterial alone and the untreated control group, there was no evidence of new tissue production. These results advocate the use of this collagen‐based scaffold for further in vivo studies on large size animals and, finally, in human clinical trials for the treatment of knee cartilage defects. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res, 2005
Supramolecular assemblies of adsorbed collagen affect the adhesion of endothelial cells
Authors: Keresztes Z. , Rouxhet P. G. , Remacle C. , Dupont‐Gillain C.
Published: August 2005

The behavior of endothelial cells (HUVECs) in contact with thin collagen films presenting different supramolecular organizations was investigated. Collagen was adsorbed on polystyrene (PS) and plasma‐oxidized PS (PSox) in conditions ensuring the formation of continuous layers presenting an increasing density of fibrillar structures. Discontinuous collagen layers were also prepared on PS by adsorption followed by dewetting. The morphology of the obtained collagen films was checked by using atomic force microscopy. HUVECs adhesion was evaluated in terms of cell number, cell area, cell shape, and actin structure after 4 h of contact with the prepared collagen layers. In the presence of serum, no adhesion was observed on PS, whereas a substantial adhesion was found on PSox. This is explained by the competition for adsorption, which turns in favor of adhesive proteins secreted by the cells on the hydrophilic PSox, but turns in favor of serum albumin on the hydrophobic PS. The progressive coating of PS by smooth collagen films increased cell adhesion and spreading. However, cell spreading and cytoskeleton organization were adversely affected by the appearance of a high density of collagen fibrillar structures. This latter trend was similarly observed on PSox. On the other hand, HUVECs spreading and cytoskeleton organization were clearly enhanced on discontinuous collagen layers compared with continuous ones. A possible explanation for these observations lies in the modification of exposure and/or spatial distribution of recognition sequences due to spontaneous collagen self‐assembly on fibril formation or to collagen aggregation on dewetting. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res, 2006
Crosslinking of collagen with dendrimers
Authors: Duan X. , Sheardown H.
Published: August 2005

Polypropyleneimine octaamine dendrimers were studied as an alternative means of generating highly crosslinked collagen. Crosslinking was effected by using the water‐soluble carbodiimide 1‐ethyl‐3‐(3‐dimethyl aminopropyl) carbodiimide hydrochloride (EDC). The multifunctional dendrimers were introduced as novel crosslinkers after the activation of the carboxylic acid groups of glutamic and aspartic acid residues in collagen. The conventional crosslinker glutaraldehyde was used as a control. EDC, itself an alternative crosslinker, which forms zero‐length crosslinks by directly covalently binding collagen molecules, as well as a low molecular weight diamine and a low molecular weight triamine, were also studied. All of the resultant gels were freeze‐dried to obtain sponges for characterization. Water uptake of the gels decreased from 90% to 60% after dendrimer crosslinking compared with EDC crosslinking. DSC results showed an increase of denaturation temperature of collagen after crosslinking with the various methods. The generation 2 and 3 dendrimer‐crosslinked collagen samples had the highest denaturation temperature, at up to 90°C compared with 50°C in the uncrosslinked collagen control. The dendrimer‐crosslinked collagen also showed unique thermal characteristics, with multiple denaturation temperature peaks in contrast to the single peak noted with the other crosslinked collagens. This is thought to be due to the heterogeneous nature of dendrimer crosslinking. Collagenase results revealed that the dendrimer‐crosslinked collagen had a comparative resistance to proteolysis to glutaraldehyde‐crosslinked collagen. Measurement of activated carboxylic acid groups before and after crosslinking indicated that 40–70% of the activated carboxylic acid was consumed during crosslinking with dendrimers. The results suggest that dendrimer crosslinking of collagen produces stable gels. The presence of a large number of excess amine groups in the dendrimers may also be useful for subsequent modification with biologically relevant groups. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res, 2005
On the feasibility of phosphate glass and hydroxyapatite engineered coating on titanium
Authors: Kim Hae‐Won , Lee Eun‐Jung , Jun In‐Kook , Kim Hyoun‐Ee
Published: August 2005

In this report, bioactive calcium phosphate (CaP) coatings were produced on titanium (Ti) by using phosphate‐based glass (P‐glass) and hydroxyapatite (HA), and their feasibility for hard tissue applications was addressed in vitro. P‐glass and HA composite slurries were coated on Ti under mild heat treatment conditions to form a porous thick layer, and then the micropores were filled in with an HA sol–gel precursor to produce a dense layer. The resultant coating product was composed of HA and calcium phosphate glass ceramics, such as tricalcium phosphate (TCP) and calcium pyrophosphate (CPP). The coating layer had a thickness of approximately 30–40 μm and adhered to the Ti substrate tightly. The adhesion strength of the coating layer on Ti was as high as 30–33 MPa. The human osteoblastic cells cultured on the coatings produced by the combined method attached and proliferated favorably. Moreover, the cells on the coatings expressed significantly higher alkaline phosphatase activity than those on pure Ti, suggesting the stimulation of the osteoblastic activity on the coatings. On the basis of these observations, the engineered CaP coating layer is considered to be potentially applicable as a hard tissue‐coating system on Ti‐based implants. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res, 2005
The phase state of NiTi implant material affects osteoclastic attachment
Authors: Muhonen V. , Heikkinen R. , Danilov A. , Jämsä T. , Ilvesaro J. , Tuukkanen J.
Published: August 2005

In the present work, the responses of mature osteoclasts cultured on austenite and martensite phases of NiTi shape memory implant material were studied. We used the sensitivity of osteoclasts to the underlying substrate and actin ring formation as an indicator of the adequacy of the implant surface. The results showed osteoclasts with actin ring on both NiTi phases. However, significantly more osteoclasts were present on the austenitic NiTi than on the martensitic NiTi. We also analyzed the surface free energy of the samples but found no significant difference between austenite and martensite phases. The results revealed that osteoclasts tolerated well the austenite phase of NiTi. The chemically identical martensitic NiTi was not as well tolerated by osteoclasts (e.g., indicated by diminished actin ring formation). This leads to the conclusion that certain physical properties specific to the martensitic NiTi have an adverse effect to the surviving of osteoclasts on this NiTi phase. These results confirm that mature, authentic osteoclasts can act as cell probes in experiments concerning aspects of biocompatibility of bone implant materials. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res, 2005
Novel approach for quantification of porosity for biomaterial implants using microcomputed tomography (μCT)
Authors: Hiu‐Yan Yeung , Ling Qin , Kwong‐Man Lee , Ming Zhang , Kwok‐Sui Leung , Chun‐yiu Cheng Jack
Published: August 2005

Porous bioceramics have been widely investigated in orthopaedic tissue engineering. Attention has been given to manufacturing of a porous bioceramic that mimics the trabecular bone structure for proper bone regeneration. With the advance of biomedical imaging through microcomputed tomography (μCT), this study attempted to quantify the pore structure of different bioceramics. Two bioceramic blocks (BSC and ChronOS) were synthesized by two methods. The specification claimed the porosity of the bioceramic ranged from 40% to 70%. Six blocks of each bioceramic were evaluated by conventional water immersion method and μCT. The pore size and connectivity were evaluated with standardized protocols. By the water immersion method, the porosity of BSC and ChronOS was 60.4% and 74.7%, respectively. The three‐dimensional results of μCT showed that BSC porosity was 26.2% and ChronOS was 60.0%. The pore connectivity was evaluated to be 2.6 for BSC and 39.7 for ChronOS. ChronOS had functional pores with 200 μm to 400 μm in diameter (87.8% ± 0.5%), which is significantly more than 52.8% ± 11.5% of pores in BSC (p < 0.05). Providing information on the functional pores objectively, the μCT evaluation serves as a good standard for specification of the bioceramic‐related implants. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2005
Benchmarking approximate density functional theory. I. s/d excitation energies in 3d transition metal cations
Authors: Holthausen Max C.
Published: August 2005

The performance of a number of different implementations of density functional theory (DFT) for predicting the s/d interconfigurational energies of the 3d transition metal cations is investigated. Systematic comparisons of computed results with experimental data indicate that gradient corrected correlation functionals, like the LYP GGA, efficiently correct the flaws of the LDA, but reveal shortcomings in the treatment of exchange by currently available GGAs. The admixture of exact exchange in hybrid functionals eventually leads to largely reduced errors. Several basis sets available for the 3d elements are tested in combination with the B3LYP functional. Finally, the influence of variations of the admixture of exact exchange is systematically tested. The results reveal that computed s/d excitation energies obtained for the individual ions depend in markedly different ways on the amount of exact exchange admixture and that there is no single optimal and transferable exchange parameter to create a hybrid functional that yields improved results for all ions alike. Several of the recently devised functionals perform as good as or slightly better than the B3LYP functional in the present study. But given the fact that the B3LYP functional has been identified as the most successful DFT method in an overwhelming number of systematic investigations in very many areas of chemical research, there is no persuasive motivation to recommend its replacement by one of the other functionals, as much less is known about their robustness. © 2005 Wiley Periodicals, Inc. J Comput Chem 26: 1505–1518, 2005
Detailed considerations for a balanced and broadly applicable force field: A study of substituted benzenes modeled with OPLS‐AA
Authors: Price Daniel J. , Brooks Charles L.
Published: August 2005

Modern classical force fields have been traditionally parameterized by attempting to maximize agreement to any number of experimental and/or quantum mechanical target properties. As these force fields are pushed towards obtaining quantitative estimates of often subtle energetic differences, stringent and consistent parameterization criteria, particularly in regard to charge distributions, are required to ensure that systematic errors cancel, that parameters are transferable between molecules, and that performance does not significantly deteriorate when using more approximate methods, such as with continuum solvent models. Relative free energies of hydration are presented here for 40 mono‐ and disubstituted benzenes modeled with the OPLS‐AA force field; heats of vaporization and pure liquid densities at standard conditions are presented when experimental data is available. Overall agreement between OPLS‐AA and experiment is remarkable (average error = 0.5 kcal/mol for ΔΔGhydration, 1.0 kcal/mol for ΔH, 0.02 g/mL for densities), yet several functional groups are identified as having consistent and correctable errors (alkyl‐, nitro‐, and thiobenzenes). Relative free energies of hydration obtained with rigorous free energy perturbations using explicit solvent are also compared with energies from minimizations using a generalized Born model (GB). There is high correlation between these estimates (R = 0.99), and as demonstrated here, reparameterization of the aforementioned groups can be guided with rapid GB calculations. © 2005 Wiley Periodicals, Inc. J Comput Chem 26: 1529–1541, 2005
Graphical approach to analyzing DNA sequences
Authors: Liao Bo , Ding Kequan
Published: August 2005

Recently, we proposed a 2D graphical representation of DNA sequence [J Comput Chem 25(2004) 1364–1368]. Based on this representation, we outline one approach to search optimal alignment. We also can judge the mutations between bases and an unknown sequence based on its graph and a known sequence's graph. © 2005 Wiley Periodicals, Inc. J Comput Chem 26: 1519–1523, 2005
Modeling lanthanide complexes: Sparkle/AM1 parameters for ytterbium (III)
Authors: Freire Ricardo O. , Rocha Gerd B. , Simas Alfredo M.
Published: August 2005

The Sparkle/AM1 model is extended to ytterbium (III) complexes. Thus, a set of 15 complexes, with various representative ligands, chosen to be representative of all complexes of high crystallographic quality (R‐factor <0.05 Å) in the Cambridge Crystallographic Database, and which possess oxygen and/or nitrogen as coordinating atoms, was used as the training set. In the validation procedure we added 32 more high quality crystallographic structures. For the 47 complexes, the Sparkle/AM1 unsigned mean error for all interatomic distances between the Yb(III) ion and the ligand atoms of the first sphere of coordination is 0.07 Å, similar to present‐day ab initio/ECP geometry prediction accuracies, and potentially useful for luminescent complex design while being hundreds of times faster. © 2005 Wiley Periodicals, Inc. J Comput Chem 26: 1524–1528, 2005
Covering arrays of higher strength from permutation vectors
Authors: Sherwood George B. , Martirosyan Sosina S. , Colbourn Charles J.
Published: August 2005

A covering array CA(N;t,k,v) is an N × k array such that every N × t sub‐array contains all t‐tuples from v symbols at least once, where t is the strength of the array. Covering arrays are used to generate software test suites to cover all t‐sets of component interactions. We introduce a combinatorial technique for their construction, focussing on covering arrays of strength 3 and 4. With a computer search, covering arrays with improved parameters have been found. © 2005 Wiley Periodicals, Inc. J Combin Designs 14: 202–213, 2006
The valuations of the near hexagons related to the Witt designs S(5,6,12) and S(5,8,24)
Authors: De Bruyn Bart , Vandecasteele Pieter
Published: August 2005

Valuations of dense near polygons were introduced in 16. In the present paper, we classify all valuations of the near hexagons 𝔼1 and 𝔼2, which are related to the respective Witt designs S(5,6,12) and S(5,8,24). Using these classifications, we prove that if a dense near polygon S contains a hex H isomorphic to 𝔼1 or 𝔼2, then H is classical in S. We will use this result to determine all dense near octagons that contain a hex isomorphic to 𝔼1 or 𝔼2. As a by‐product, we obtain a purely geometrical proof for the nonexistence of regular near 2d‐gons, d ≥ 4, whose parameters s, t, ti (0 ≤ i ≤ d) satisfy (s, t2, t3) = (2, 1, 11) or (2, 2, 14). The nonexistence of these regular near polygons can also be shown with the aid of eigenvalue techniques. © 2005 Wiley Periodicals, Inc. J Combin Designs 14: 214–228, 2006
Moments of graphs in monotone families
Authors: Füredi Zoltán , Kündgen André
Published: August 2005

The kth moment of the degree sequence d1 ≥ d2 ≥ …dn of a graph G is $\mu _k(G)={1\over n}{\sum}{d_i^k}$. We give asymptotically sharp bounds for μk(G) when G is in a monotone family. We use these results for the case k = 2 to improve a result of Pach, Spencer, and Tóth [15]. We answer a question of Erdős [9] by determining the maximum variance ${\mu _2(G)-\mu _1^2(G)}$ of the degree sequence when G is a triangle‐free n‐vertex graph. © 2005 Wiley Periodicals, Inc.
Proton spin–spin relaxation time of peel and flesh of navel orange varieties exposed to freezing temperature
Authors: Gambhir Prem N , Choi Young J , Slaughter David C , Thompson James F , McCarthy Michael J
Published: August 2005

Proton spin–spin relaxation times (T2) of peel (albedo and flavedo) and juice sacs (flesh segments) of navel oranges were measured at 10 MHz using a Bruker Minispec PC 110 NMR spectrometer. The oranges were subjected to chilling (5 °C) and freezing (−7 °C) temperatures for 20 h and warmed to room temperature before peeling for T2 measurements. The exposure to chilling or freezing temperature did not affect the T2 values of peel, but freezing caused an appreciable decrease (∼15%) in the T2 values of flesh segments of the varieties of navel oranges studied. When the peel was exposed to −20 °C, the T2 showed a drastic reduction suggesting that the peel did not freeze at −7 °C. The possible cause of reduction in the T2 values when exposed to freezing temperature may be damage to the juice sac membrane and leakage of juice out of the sac. The difference in the T2 values between juice sacs of freeze‐affected and normal oranges can potentially be used for detection of freeze‐damaged fruits. Copyright © 2005 Society of Chemical Industry
Relationship between glutenin subunit composition and gluten strength measurements in durum wheat
Authors: Sissons Mike J , Ames Nancy P , Hare Ray A , Clarke John M
Published: August 2005

Durum breeders use a range of techniques in the development of new cultivars. An important selection criterion is the rheological properties of semolina dough and durum wheat breeders use this criterion in the development of new cultivars using a range of techniques. Because of the need to process large numbers of genotypes encountered in breeding programs, methods that are inexpensive, rapid, require small amounts of sample and that correlate with semolina quality are desirable. Using breeding material, this study investigated the relationship between the glutenin subunit composition and two traditional tests of gluten strength, gluten index (GI) and mixograph. Two sample sets of durum wheat breeding lines and cultivars, one grown in Canada (n = 229) and the other grown in Australia (n = 139) were analysed for GI, mixograph and both high molecular weight (HMW) and low molecular weight (LMW) glutenin subunits by SDS‐PAGE. Nine different HMW and 14 different LMW allelic combinations were found. In the Canadian set, the most frequent LMW alleles were aaa, bba, caa and cfa while in the Australian set, caa was predominant. For the HMW subunits, the most common allelic groups were Glu‐A1c/Glu‐B1d (null, 6 + 8) and Glu‐A1c/Glu‐B1b (null, 7 + 8) with fewer numbers of Glu‐A1c/Glu‐B1e (null, 20) in both sample sets. LMW subunits were more important contributors to gluten strength than HMW subunits with the rank for higher GI according to the LMW allele (Canadian set) being caa = aaa > bba and aaa > cfa while HMW subunits 6 + 8 = 7 + 8 > 20. Similarly, using the mixograph, strength ranking for the LMW alleles was aaa > cfa = bba and HMW subunit 20 gave poorer rheological properties. For some samples with a good LMW allelic group a low GI was observed and vice versa. Further characterisation of the protein composition in these samples showed the GI results could be explained by polymeric/monomeric (P/M), glutenin/gliadin (Glu/Gli) and HMW/LMW ratios or the proportion of unextractable polymeric protein. © Crown in the right of the State of New South Wales, Australia; and for the Department of Agriculture and Agri‐Food, Government of Canada, © Minister of Public Works and Government Services Canada 2005. Published for SCI by John Wiley & Sons, Ltd.
Acid hydrolysis and fermentation of brewer's spent grain to produce xylitol
Authors: Mussatto Solange I , Roberto Inês C
Published: August 2005

The hemicellulosic fraction of brewer's spent grain (BSG) was hydrolysed with diluted acid under different conditions of liquid/solid ratio (8–12 g g−1), sulfuric acid concentration (100–140 mg g−1 dry matter) and reaction time (17–37 min) in order to produce a liquor with a large amount of xylose and good fermentability to produce xylitol. Results showed that all the evaluated reaction conditions were able to hydrolyse xylan and arabinan with efficiencies higher than 85.8 and 95.7% respectively, and even under the mildest reaction condition a considerable amount (92.7%) of the hemicellulosic fraction could be extracted. The hydrolysates presented different fermentabilities when used as fermentation media for xylitol production by Candida guilliermondii yeast, owing to the differences in their composition. Based on statistical analysis, the best condition for BSG acid hydrolysis was the use of a liquid/solid ratio of 8 g g−1, 100 mg H2SO4 g−1 dry matter and a reaction time of 17 min. Under this condition a high extraction efficiency of hemicellulosic sugars (92.7%) and good fermentation results (YP/S = 0.70 g g−1 and QP = 0.45 g dm−3 h−1) were attained. Copyright © 2005 Society of Chemical Industry
Changes in chemical composition of lupin seeds (Lupinus angustifolius) after selective α‐galactoside extraction
Authors: Torres Alexia , Frias Juana , Vidal‐Valverde Concepción
Published: August 2005

A selective procedure for the extraction of α‐galactosides has been employed in two sweet lupin seeds (Lupinus angustifolius var. Troll and var. Emir) in order to reduce flatulence‐causing factors. Different nutritional parameters (proteins, fat, ash, dietary fibre, starch, sucrose, vitamins B1, B2, E and C) and antinutritional factors (α‐galactosides, trypsin inhibitor activity and inositol phosphates) were studied in raw and processed seeds. The α‐galactoside content in both varieties was reduced by 87–100%. The extracted lupins seeds presented a high retention in protein and fat (109–136% and 95–104%, respectively). Sucrose and soluble dietary fibre, however, decreased significantly as a result of processing and retentions ranged between 5 and 29%. The vitamin B1, B2, and E contents decreased during selective extraction, the retentions being in the ranges 25–47%, 38–40%, and 48–54%, respectively, for var. Troll and Emir. However extracted lupin seeds still contained important amounts of vitamins and insoluble dietary fibre, compounds with nutritional importance. Raw and processed lupins did not contain starch. TIA and vitamin C were not detected, and total inositol phosphates were modified slightly after extraction. In conclusion, the lupin seeds obtained by the extraction of α‐galactosides can be an adequate proteic ingredient to be incorporated in functional foods. Copyright © 2005 Society of Chemical Industry
Cytochemical characterization and structural approach to Prosopis juliflora (Sw) D.C. seed gum extraction
Authors: Gallão Maria I , Furtado Ricardo S , de Brito Edy S
Published: August 2005

Mesquite seed is a good gum source. In this work seed structure was characterized in order to help seed gum extraction. Seed gum was located between cotyledon and seed coat. Milling process yielded, basically, two fractions: endosperm and seed coat plus gum. This fact was supported by the cytochemical observation of a dense layer near the seed coat and a loose layer near the endosperm. Cells containing seed gum had thick cell walls and a proteic core. Seed gum extraction implications are discussed. Copyright © 2005 Society of Chemical Industry
Extending storage life of fresh ginseng by modified atmosphere packaging
Authors: Hu Wenzhong , Xu Ping , Uchino Toshitaka
Published: August 2005

Fresh ginseng (Panax ginseng) was packaged with LDPE and PVC films. The respiration rates of fresh ginseng were determined in modified atmosphere packaging (MAP) at 0, 10 and 20 °C. The changes in chemical compositions were also measured before and after storage. The results showed that respiration rates of fresh ginseng were suppressed more effectively in MAP, especially in a poly(vinyl chloride) (PVC) package. The storage life of fresh ginseng was significantly extended with better appearance and firmness for 210 days. The decay rate was only 1.3% and 1.0% in both low density polyethylene (LDPE) and PVC film package after 210 days of storage at 0 °C, respectively. The results of saponin analysis indicated that the contents of total saponin were not changed much in all treatments. Reducing sugar was increased by 2.7 to 5.3 times, while pectin decreased by 1.1 to 1.4 times after 210 days of storage at the range of 0–20 °C. Total sugar content also increased during storage, especially in LDPE packages and high temperature. It was considered that MAP was very effective storage method for keeping quality better with minimal quality loss and lower decay rate at lower temperature. Copyright © 2005 Society of Chemical Industry
Consumers' preferences for beef in the Spanish region of Extremadura: a study using conjoint analysis
Authors: Mesías Francisco J , Escribano Miguel , de Ledesma Antonio Rodríguez , Pulido Francisco
Published: August 2005

The study of consumers' preferences is of great interest in the beef sector, where the BSE crisis generated deep changes in the basic conditions of demand for meat and in the behaviour of consumers. Previous qualitative research showed that ‘price’, ‘origin’, ‘production system’ and ‘labelling’ were the main attributes affecting preferences for beef in Extremadura (SW Spain). The data were obtained by a survey carried out between February and April 2002 with a sample of 575 regular consumers of beef. Conjoint Analysis has been used to estimate the relative importance of those attributes and to determine the existence of consumer segments with similar preference profiles. Results show that the origin of the product is the most important attribute for the choice of beef, followed by quality labelling, production system and price. Three groups of consumers were identified through cluster analysis, according to their preferences for beef. Copyright © 2005 Society of Chemical Industry
In vitro culture of Pandanus amaryllifolius and enhancement of 2‐acetyl‐1‐pyrroline, the major flavouring compound of aromatic rice, by precursor feeding of L‐proline
Authors: Thimmaraju R , Bhagyalakshmi N , Narayan MS , Venkatachalam L , Ravishankar GA
Published: August 2005

Shoots, plantlets and semi‐differentiated callus (SDC) cultures of Pandanus amaryllifolius capable of producing high levels of basmati rice flavour were established in vitro using Murashige and Skoog nutrient medium. A total of 10% of the initial explants responded to produce shoot cultures in the presence of benzylamino purine (BAP) (0.5 mg L−1) and glutamine (100 mg L−1). Leaf explants and basal portions of shoots produced SDC whereas elongated in vitro shoots could be continuously multiplied, using BAP (1.5 mg L−1) and kinetin (Kn) (1.0 mg L−1), and rooted in half‐strength medium for ex vitro cultivation leading to a process of micropropagation. Steam‐distillation extraction (SDE) followed by gas chromatography‐mass spectrometry (GC‐MS) analysis of various cultured organs and spent liquid medium used for SDC revealed the presence of 2‐acetyl‐1‐pyrroline (2‐AP) to various extents. This 2‐AP compound has been identified as the major flavouring compound of scented basmati and other scented rice varieties. 2‐AP was found to be highest, on a fresh weight basis, in SDC (19.7 mg kg−1) on the 40th day, whereas in vitro roots, shoots and field leaves (of one‐year‐old plant) had lower levels of 15, 6.8 and 14 mg kg−1, respectively. Further enhancement of 2‐AP in SDC using precursor was possible by feeding into medium 1 mmol L−1 of L‐proline where a highest level of 21.67 ppm of 2‐AP accumulated on the seventh day whereas a higher level of 2 mmol L−1 of L‐proline suppressed 2‐AP levels. The present report is the first on the tissue culture studies of P. amaryllifolius where continuous production of plantlets as well as synthesis of high levels of 2‐AP has been documented. Copyright © 2005 Society of Chemical Industry
Soybean cultivars impact quality and function of soymilk and tofu
Authors: Kim Yookyung , Wicker Louise
Published: August 2005

The functional properties of soymilk and tofu prepared from Benning and Danbaekkong soy cultivars were identified. The protein content in soymilk was significantly higher for Danbaekkong, at 46.4 g kg−1, than for Benning at 42.0 g kg−1. The 11S/7S globulin ratios of Danbaekkong and Benning were estimated at 0.93 and 0.38, respectively. Soymilk from Danbaekkong was more non‐Newtonian (n = 0.69) than soymilk from Benning (n = 0.84). Tofu prepared from Danbaekkong was significantly harder, chewier and gummier than tofu from Benning. Differences in protein content, protein ratio, viscosity, textural properties and color of soymilk can be applied as indicators of quality and functionality in soy foods such as tofu. Copyright © 2005 Society of Chemical Industry
Decontamination of aflatoxin‐contaminated maize by dehulling
Authors: Siwela Andrew H , Siwela Mthulisi , Matindi Gibson , Dube Shadreck , Nziramasanga Nozipho
Published: August 2005

Dehulling of maize grains as an aflatoxin decontamination method was investigated. Sixty kilograms of maize (whose average moisture content was 110 g kg−1) were thoroughly mixed and divided into two samples. The kernel moisture content of one sample was adjusted to 200 g kg−1 while the other (control) was left at 110 g kg−1. The two samples were kept at ambient temperature (25–30 °C) for 21 days. Twenty sub‐samples, ten from each, were further divided into two so that one lot was dehulled while the other was not dehulled. These sub‐samples were then milled to pass through a 1 mm screen and the meal was evaluated for aflatoxin contamination. It was found that there was a 92% decrease in aflatoxin levels in dehulled maize meal compared with undehulled maize meal. We therefore suggest that dehulling the grain can be used to reduce aflatoxin levels in maize. Copyright © 2005 Society of Chemical Industry
Comparison of sheep and red deer rumen fluids for assessing nutritive value of ruminant feedstuffs
Authors: Hervás Gonzalo , Ranilla María J , Mantecón Ángel R , Tejido María L , Frutos Pilar
Published: August 2005

Four forages (alfalfa hay, barley straw, maize silage and beet pulp), four cereal grains (barley, maize, sorghum and wheat) and four shrubs (Calluna vulgaris, Erica australis, Cytisus cantabricus and Genista occidentalis) were incubated using rumen fluids from sheep and red deer, to examine differences in in vitro fermentation rates and ruminal parameters. For the forages and cereal grains, results suggest few differences between species in parameters related to gas production, rates of fermentation, organic matter disappearance and extent of degradation. Deer showed slightly better results for shrubs than sheep did. Disappearance of neutral detergent fibre was generally greater when the rumen fluid was derived from red deer (P < 0.05). On the other hand, ammonia‐N concentration and total volatile fatty acids (VFAs) were higher in sheep (P < 0.05). Molar proportions of the major VFAs showed significant differences (P < 0.05) associated with the species of the inoculum donor and suggest that fermentation pathways might have been more efficient in red deer. The estimated amount of methane was higher in sheep, regardless of the substrate incubated (P < 0.001). The results indicate that although the sheep could be valid as a model to assess the nutritive value of good quality feedstuffs for red deer, it would fail to offer reliable information on non‐conventional, low‐quality feeds such as shrubs. Copyright © 2005 Society of Chemical Industry
The phenolic acid and polysaccharide composition of cell walls of bran layers of mature wheat (Triticum aestivum L. cv. Avalon) grains
Authors: Parker Mary L , Ng Annie , Waldron Keith W
Published: August 2005

The purpose of this study was to examine the carbohydrate and phenolic‐ester composition of cell walls in wheat bran layers. Four defined layers of wheat bran were separated manually from mature grains of wheat (Triticum aestivum L. cv. Avalon) to give samples of beeswing bran (outer pericarp), cross cells, testa + nucellar epidermis and aleurone cells. The cell‐wall material from each layer, and from a sample of intact bran, was analysed for carbohydrates and wall‐bound esterified phenolic acids. The cell‐wall material of intact bran was rich in arabinose and xylose with significant quantities of glucose and uronic acid and a relatively small amount of galactose and mannose. The varying ratios of arabinose:xylose in cell walls of isolated bran layers indicated that the heteroxylans had tissue‐specific substitution patterns. HPLC analysis of phenolic acids identified significant amounts of esterified ferulic acid and 8‐8′‐ (aryltetralin form), 5‐8′‐, 5‐5′‐, 8‐0‐4′‐ and 5‐8′‐(benzofuran form)‐dehydrodiferulic acids in the isolated cell walls. Ferulic acid was highly concentrated in the aleurone layer, whereas dehydrodiferulates were concentrated in the beeswing bran and cross cells. The role of phenolic cross‐linking is discussed in relation to the architecture of the cell walls of wheat bran and to processing implications. Copyright © 2005 Society of Chemical Industry
Simultaneous determination of cefepime and L‐arginine by micellar electrokinetic chromato‐ graphy and applications to commercial injections
Authors: Chen Yi‐Ru , Lin Shun‐Jin , Chou Yu‐Wei , Wu Hsin‐Lung , Chen Su‐Hwei
Published: August 2005

A simple micellar electrokinetic chromatography (MEKC) with UV detection is described for simultaneous analysis of cefepime and L‐arginine. The determination of cefepime and L‐arginine in pharmaceutical preparations was performed at 25°C using a background electrolyte consisting of Tris buffer with sodium dodecyl sulfate (SDS) as the electrolyte solution. Several parameters affecting the separation of the drugs were studied, including the pH and concentrations of the Tris buffer and SDS. Under optimal MEKC conditions, good separation with high efficiency and short analysis times is achieved. Using cefazolin as an internal standard, the linear ranges of the method for the determination of cefepime and L‐arginine were over 5–100 μg/mL; the detection limits of cefepime (signal to noise ratio = 3; injection 3.45 kPa, 3 s) and L‐arginine (signal to noise ratio = 3; injection 3.45 kPa, 3 s) were 2 μg/mL and 4 μg/mL, respectively. Applicability of the proposed method for the determination of cefepime and L‐arginine in commercial injections was demonstrated.
Turbulent flow chromatography for the reduction of matrix effects in electrospray ionization mass spectrometry‐based enzyme assays
Authors: Liesener André , Karst Uwe
Published: August 2005

Turbulent flow chromatography (TFC) is presented as a means to reduce ion suppression in simultaneous multianalyte mass spectrometric bioassays. In this study, the effects of enzymes present in the sample on the signal response of five analytes were simultaneously investigated over a protein content range from 0 to 38 μg/mL by means of direct flow injection MS. As model enzymes, trypsin, thrombin, and chymotrypsin were selected. Without employment of TFC, both signal suppression and signal enhancement, depending on the nature of the analyte and the amount of matrix in the sample, were observed. Generally, these matrix effects were found to be intolerably large. The deviation from the mean signal response as a measure of deterioration was found to be between 14 and 112%. The addition of an excess of methanol as means of sample clean‐up was investigated and found not to be sufficient. By employing TFC for online sample preparation, it was possible to reduce the matrix effects to a minimum for all model systems investigated. In case of trypsin the distortion could be lowered from 41.9 to 2.6%. Thus, TFC is considered to be a highly valuable tool for improving the sensitivity and reliability in the monitoring of enzymatic conversions by means of MS.
Two‐dimensional separation of peptides using RP‐RP‐HPLC system with different pH in first and second separation dimensions
Authors: Gilar Martin , Olivova Petra , Daly Amy E. , Gebler John C.
Published: August 2005

Two‐dimensional high performance liquid chromatography is a useful tool for proteome analysis, providing a greater peak capacity than single‐dimensional LC. The most popular 2D‐HPLC approach used today for proteomic research combines strong cation exchange and reversed‐phase HPLC. We have evaluated an alternative mode for 2D‐HPLC of peptides, employing reversed‐phase columns in both separation dimensions. The orthogonality of 2D separation was investigated for selected types of RP stationary phases, ion‐pairing agents and mobile phase pH. The pH appears to have the most significant impact on the RP‐LC separation selectivity; the greatest orthogonality was achieved for the system with C18 columns using pH 10 in the first and pH 2.6 in the second LC dimension. Separation was performed in off‐line mode with partial fraction evaporation. The achievable peak capacity in RP‐RP‐HPLC and overall performance compares favorably to SCX‐RP‐HPLC and holds promise for proteomic analysis.
Nd:YAG/V:YAG microchip laser operating at 1338 nm
Authors: Šulc J , Jelínková H , Nejezchleb K , Škoda V
Published: August 2005

Q-switched microchip laser emitting radiation at
wavelength 1338 nm was designed and constructed. This laser was
based on a monolith crystal which combines in one piece a cooling
undoped part (undoped YAG crystal), an active laser part
(Nd3+:YAG), and a saturable absorber (V3+:YAG,
T
0=85%). The microchip resonator consists of dielectric
mirrors directly deposited on the monolith surfaces. The output
coupler with reflection 90% was placed on the V3+-doped
part. Q-switched microchip laser was tested under pulsed, and CW
diode pumping. The pulse length was the same for all regimes and
it equals to 6.2 ns. The wavelength of linearly polarized laser
emission was 1338 nm. For pulsed pumping the output pulse energy
was stable up to mean pump power 1 W and it was equal to
131 μJ, which corresponds to peak power 21 kW. In CW regime
for pumping up to 14 W the pulse energy was 37 μJ.
Anterior eye tissue transmission for the radiation with the
wavelength from eye safe region
Authors: Jelínková H , Pašta J , Šulc J , Němec M , Koranda P
Published: August 2005

Comparison of the eye tissue transmission for six laser
radiations from visible up to mid- infrared region was done. The
attenuation of the alexandrite (visible 0.75 μm), and Nd:YAP
(near infrared 1.08 μm) laser radiations was found to be
minimal – a retina reachs ∼46% energy of these lasers
entering the eye. On the other side the radiations of 1.54 μm
(Er:glass), 1.66 μm (Er:YAP), and 2.01 μm (Tm:YAG) lasers
are absorbed by the anterior segments of the eye and no impact is
appeared on the retina. The absorption values measured for
1.34 μm (Nd:YAP) was recorded to be between the curves
obtained for two groups of radiation wavelengths mentioned above.
On retina, only 0.5% of the cornea radiation level was found. In
this case the anterior parts of the eye are affected partially but
not so deeply as in the case of eye safe radiation application.
Hydrogenic impurity in two-dimensional semiconductors with anisotropic energy spectrum of carriers
Authors: Andreev S P , Pavlova T V
Published: August 2005

The binding energy and wave function of a ground state of a shallow hydrogenic impurity in two-dimensional semiconductors with isotropic and anisotropic effective mass of carriersm*= {m⊥,m⊥,m||} are derived. The calculations are performed by the variational method based on a two-parametric trial wave function. The dependence of binding energy and deformation of an impurity on 2D layer thickness and effective mass anisotropy parameterm⊥/m||is investigated. The obtained results are in a good agreement with experimental data and in the limiting cases coincide with the theoretical calculations of shallow impurity binding energy for bulk semiconductors [1] and two-dimensional semiconductors with isotropic effective mass of electrons [2].
Copying of quantum information by means of a quantum amplifier
Authors: Sych D V , Grishanin B A , Zadkov V N
Published: August 2005

Information aspects of copying quantum states via
stimulated emission of an optical quantum amplifier are
considered. It is shown that the measurable information very
rapidly decreases after amplification of a single photon up to a
level of several photons. Spontaneous emission, which leads to
such behavior, is also discussed.
Brisk deep‐tendon reflexes as a distinctive phenotype in an argentinean spinocerebellar ataxia type 2 pedigree
Authors: Rosa Alberto L. , Molina Irma , Kowaljow Valeria , Conde Cecilia B.
Published: August 2005

Slow saccades, postural/intention tremor, peripheral neuropathy, and decreased deep‐tendon reflexes are valuable neurological signs for clinical suspicion of spinocerebellar ataxia type 2 (SCA2). We report the presence of abnormally brisk deep‐tendon reflexes in nonsymptomatic carriers and mildly and severely affected subjects of a large Argentinean SCA2 pedigree. The identification of this distinctive SCA2 phenotype in an entire pedigree reinforces the current concept that clinical algorithms are of limited value as indicators for genetic testing in SCA. Combined with published pedigrees of SCA2 manifesting as levodopa‐responsive parkinsonism, this finding suggests that modifier genes could influence the clinical phenotype of SCA2. © 2005 Movement Disorder Society
Osteoporosis in Parkinson's disease
Authors: Wood Brian , Walker Richard
Published: August 2005

There are few studies of osteoporosis in Parkinson's disease (PD). We assessed the prevalence of osteoporosis in a PD clinic cohort. All subjects with a confirmed diagnosis of PD attending a clinic were invited to participate. All consenting subjects had bone density measured by dual energy X‐ray absorptiometry scanning. Further data, including demography, disease duration, and disease severity, were collected. One hundred five subjects participated; median age was 75 (54–92) years. Fifty‐one (49%) patients were men. Of the men: median T score, −1.3 (range, −4.7 to 3.8); median Z score, 0.0 (−3.2 to 4.7); diagnostic categories: osteoporosis, 20%; osteopenia, 41%; normal, 39%. Of the women: median T score −2.7 (−4.7 to 1.4); median Z score, −0.25 (−2.6 to 4.2); diagnostic categories: osteoporosis, 63%; osteopenia, 28%; and normal, 9%. Whole sample: osteoporosis, 42%; osteopenia, 34%; and normal, 24%. There were associations between age, depression, disease duration, and osteoporosis but not with disease severity. Female gender was an independent predictor of osteoporosis. The prevalence of osteoporosis/osteopenia is considerable in PD patients but does not exceed that of other people of similar age. Osteoporosis/osteopenia was present in almost all women of this age group with PD. © 2005 Movement Disorder Society
Myoclonus of the scapula after acute long thoracic nerve lesion: A case report
Authors: Camerota Filippo , Celletti Claudia , Paoloni Marco , Serrao Mariano , Inghilleri Maurizio , Pierelli Francesco , Santilli Valter
Published: August 2005

We describe a patient who presented myoclonus in the left scapula 3 months after a traumatic lesion of the left long thoracic nerve. Myoclonic activity was recorded as pseudorhythmic electromyographic bursts repeated at a frequency of 2 to 4 Hz, each lasting between 100 and 200 msec, in the left serratus–dorsalis muscle region, trapezius, and deltoid muscles. A combination of peripheral and central mechanisms may have induced the myoclonus in this case. © 2005 Movement Disorder Society
Dystonia gravidarum: A new entity?
Authors: Lim Erle Chuen‐Hian , Seet Raymond Chee‐Seong , Wilder‐Smith Einar P.V. , Ong Benjamin Kian‐Chung
Published: August 2005

We describe cervical dystonia occurring in a 31‐year‐old, previously well, primigravid, primiparous Chinese woman at 4 weeks' amenorrhea, which was ameliorated with low‐dose clonazepam and disappeared completely by the end of the second trimester without recurring despite her being tapered off benzodiazepine therapy. Investigations were unremarkable for structural and biochemical causes of dystonia. Chorea, paraballismus, and restless legs syndrome are known to occur during pregnancy, attributable to high estrogen levels. Dystonia, on the other hand, has not been described to occur de novo in pregnancy. This association should be considered in women of reproductive age who present with cervical dystonia. © 2005 Movement Disorder Society
Rating scale for psychogenic movement disorders: Scale development and clinimetric testing
Authors: Hinson Vanessa K. , Cubo Esther , Comella Cynthia L. , Goetz Christopher G. , Leurgans Sue
Published: August 2005

We developed and tested the clinimetric properties of a scale for psychogenic movement disorders (PMDs). PMDs are disabling but lack any generally accepted treatment strategies. To develop treatments, means of assessing disease severity must be provided. No scale to assess PMDs existed. The PMD scale developed here rates 10 phenomena (rest tremor, action tremor, dystonia, chorea, bradykinesia, myoclonus, tics, athetosis, ballism, cerebellar incoordination), 2 functions (gait, speech), and 14 body regions. To study interrater agreement, three movement disorder neurologists independently rated 88 videotapes of PMD patients. Data analysis was performed using a kappa coefficient of agreement, Kendall's coefficient of concordance, Spearman correlations, and intraclass correlation coefficients. Validity and scale responsiveness were tested as well. All phenomena and speech and gait dysfunction occurred in the patient sample. A wide range of affected body regions, severity, and incapacitation was captured. Ratings showed excellent interrater reliability for presence or absence of each phenomenon (κ range, 0.63 to 0.86). Kendall's concordance coefficients for phenomenology, function, and total PMD scores were 0.92, 0.93, and 0.91. Spearman correlations between raters ranged from 0.86 to 0.90. The scale was responsive to changes that occurred as a result of a neuropsychiatric intervention. The PMD scale adequately captures the complex movements of PMDs and can be used to assess PMDs and test the efficacy of intervention strategies. © 2005 Movement Disorder Society