bluuebunny/crossref_metadata_2025 huggingface dataset:
Myo-inositol content in pteridophytes and the isolation and characterization of L-myo-inositol-1-phosphate synthase from Diplopterygium glaucum
Authors: Chhetri D. R. , Mukherjee A. K. , Adhikari J.
Published: October 2006

Myo-inositol is involved in normal growth and development of all living organisms and L-myo-inositol-1-phosphate synthase (MIPS; EC: 5.5.1.4) is responsible for its de novo synthesis. This enzyme has been reported for a number of life forms including plants, animals and bacteria. In the present study free myo-inositol has been detected in the common pteridophytes found in the Darjeeling Himalayas and the enzyme, L-myo-inositol-1-phosphate synthase has been partially purified from Diplopterygium glaucum (Thunb.) Nakai. A crude homogenate from the reproductive pinnules of D. glaucum was subjected to streptomycin sulphate precipitation and 0-70% ammonium sulphate fractionation followed by successive chromatography through DEAE-cellulose, Hexylagarose and BioGel A-0.5m columns. This resulted in a partial purification of the enzyme of about 81-fold with 13.5% recovery. The pteridophytic MIPS specifically utilized D-glucose-6-phosphte and NAD+ as its substrate and co-factor, respectively. It shows a pH optimum between 7.0 and 7.5 while the temperature maximum was 30 °C. The enzyme activity was stimulated by NH4+, slightly inhibited by Na+, Ba2+ and Cd2+, and strongly inhibited by Li+, Zn2+ and Hg2+. EDTA, pCMB and some substrate isomers like glucose-1-phosphate, fructose-6-phosphte and galactose-6-phosphate were inhibitory to the enzyme. The apparent molecular weight of the native D. glaucum MIPS was determined to be approximately 171 kDa.
Interactive effects between supplemental ultraviolet-B radiation and heavy metals on the growth and biochemical characteristics of Spinacia oleracea L.
Authors: Shweta Mishra , Agrawal S.B.
Published: October 2006

The impact of supplemental UV-B (sUV-B) radiation and heavy metals: Cd (68 µmol.kg-1 soil) and Ni (68 µmol.kg-1 soil) singly and in combination was studied on photosynthetic and non-photosynthetic pigments, metabolites, enzyme activities, biomass accumulation and the net primary productivity of spinach (Spinacia oleracea L. var. All Green), a common leafy vegetable plant. Both the stresses individually and in combination resulted in the reduction of photosynthetic pigments, ascorbic acid, and catalase activity, whereas a reverse trend was observed for anthocyanin, flavonoids and proline content, lipid peroxidation and peroxidase activity. The interactive effects of both the stresses were, however, less than additive. Combined treatment of sUV-B + Cd was more deleterious as compared to sUV-B + Ni and other individual treatments.
Amino acid and ureide transport in the xylem of symbiotic soybean plants during short-term flooding of the root system in the presence of different sources of nitrogen
Authors: Thomas André Luís , Sodek Ladaslav
Published: October 2006

The transport of organic N compounds to the shoot in the xylem sap of nodulated soybean plants was investigated in an attempt to better understand the changes in N metabolism under root hypoxia (first 5 days of flooding), with different sources of N in the medium. NO3- is beneficial for tolerance of plants to waterlogging, whereas other N sources such as NH4+ and NH4NO3, are not. Nevertheless, in the presence of NH4+ high levels of amino acids were transported in the xylem, consistent with its assimilation. Some increase in the transport of amino acids was also seen with NO3- nutrition during waterlogging, but not with N-free medium. Ureide transport in the xylem was severely reduced during waterlogging, consistent with impaired N2 fixation under these conditions. The relative proportions of some amino acids in the xylem showed dramatic changes during treatment. Alanine increased tremendously under root hypoxia, especially with NH4+ as N source, where it reached near 70 % of the total amino acids present. Aspartic acid, on the other hand, dropped to very low levels and was inversely related to alanine levels, consistent with this amino acid being the immediate source of N for alanine synthesis. Glutamine levels also fell to a larger or lesser extent, depending on the N source present. The changes in asparagine, one of the prominent amino acids of the xylem sap, were most outstanding in the treatment with NO3-, where they showed a large increase, characteristic of plants switching from dependence on N2 fixation to NO3- assimilation. The data indicate that the lesser effectiveness of NH4+ during waterlogging, in contrast to NO3-, involves restricted amino acids metabolism, and may result from energy metabolism being directed towards NH4+ detoxification.
Histologic evaluation of pulpotomy performed with ethyl-cyanoacrylate and calcium hydroxide
Authors: Albuquerque Diana Santana de , Gominho Luciana Ferraz , Santos Roberto Alves dos
Published: October 2006

The aim of this study was to evaluate histological aspects of the pulp-dentin complex of dogs submitted to pulpotomy and capped with ethyl-cyanoacrylate and calcium hydroxide. Thirty dog teeth were divided into 2 groups of 15 as follows: Group 1 - ethyl-cyanoacrylate; Group 2 - calcium hydroxide. The pulpotomies were carried out following all of the treatment precautions recommended for dogs. After 30 days the specimens were submitted to histological preparation and were then blindly evaluated by a histologist. Data were analyzed statistically by the Fisher exact test, comparing the two groups. After 30 days, the presence of a hard tissue barrier was observed in 83.3% of Group 1, and in 100% of Group 2 (p = 0.478). A continuous hard tissue barrier was observed in 50% of the ethyl-cyanoacrylate group and 75% of the calcium hydroxide group (p = 0.652). It can be concluded that both materials induced hard tissue barrier formation, but Group 2 had a higher percentage than Group 1, with no significant statistical differences; the differences observed between the different barriers (continuous/non-continuous) were not significant between groups and there was no pulpal necrosis in either group.
Dimensional stability of distances between posterior teeth in maxillary complete dentures
Authors: Consani Rafael Leonardo Xediek , Mesquita Marcelo Ferraz , Correr-Sobrinho Lourenço , Tanji Maurício
Published: October 2006

The aim of this study was to assess the displacement of posterior teeth in maxillary complete dentures stored in water at 37°C. Twenty acrylic resin-based maxillary complete dentures were constructed with the anterior teeth arranged in normal overlap and the posterior teeth in Angle class I. Metallic pins were placed on the labial cusp of the first premolars (PM), and on the mesiolabial cusp of the second molars (M). The final acrylic resin pressing was made in a metallic flask with aid of the RS tension system, and polymerized in a moist-hot cycle at 74°C for 9 hours. The dentures were deflasked after cooling in their own polymerizing water or after cooling in polymerizing water plus bench storage for 3 hours, and stored in water at 37°C for periods of 7, 30, and 90 days. Following deflasking and after each storage period tested, the PM-PM (premolar to premolar), M-M (molar to molar), LPM-LM (left premolar to left molar), and RPM-RM (right premolar to right molar) distances were measured with an STM Olympus microscope, with an accuracy of 0.0005 mm. Collected data were submitted to ANOVA and Tukey's test (5%). There was no statistically significant difference for the PM-PM, M-M, and LPM-LM distances after all storage periods when the flask cooling methods were considered. With exception of the RPM-RM distance after the 30-days water plus bench storage period, the other distances remained statistically stable.
The pediatric patient at a maxillofacial service: eye prosthesis
Authors: Mattos Beatriz Silva Câmara , Montagna Maria Cecília , Fernandes Clemente da Silva , Sabóia Antonio Carlos Lorenz
Published: October 2006

Congenital absence or loss of the ocular globe during childhood causes psycho-social and cosmetic disorders and compromise the normal development of the orbital region. The literature relating to congenital or acquired etiology, due to trauma or disease, demonstrates the necessity of prevention and early detection in order to minimize the sequelae and disturbances in orbital growth. Installation of an eye prosthesis is essential to the rehabilitation process, so as to produce satisfactory development of the region. In order to characterize a profile of the child patient with this condition, a survey was carried out at the Prosthetic Eye sector, Out-patient Clinic, Discipline of Maxillofacial Prosthodontics, School of Dentistry, University of São Paulo (FOUSP), during the period from 1988 to 2003. The 124 (14.02%) patients within the age group of 0-13 years registered for ocular prosthesis were divided into a first group of 64 patients (51.62%) with 0-7 years, and a second group of 60 patients (48.38%) with 8-13 years. Fifty nine were girls and 65 were boys. No statistical significance was observed regarding the distribution of genders in the two analyzed age groups (p = 0.069). However, there was statistical significance at the level of 0.01 in relation to etiology, with higher prevalence of congenital and pathological disturbances in the younger group and traumatic occurrences in the older group. The etiology also presented variation according to the gender, at the significance level of 0.05, where girls presented three times less trauma than boys in the older age group. The necessity of prosthetic ocular repair was evenly distributed along the childhood period and the eye losses that required prosthetic treatment equally affected both genders. However, the etiology of eye loss varied according to the considered gender and age bracket.
Aerobic thermophilic pretreatment of mixed sludge for pathogen reduction and Nocardia control
Authors: Pagilla Krishna R. , Craney Kent C. , Kido Wendell H.
Published: October 2006

Pilot scale experiments have been conducted to investigate the use of aerobic thermophilic pretreatment (ATP) of mixed (waste activated and primary) sludge before mesophilic anaerobic digestion to meet Class A sludge pathogen control requirements. The ability of ATP to control Nocardia present in the waste activated sludge, and hence prevent foaming in the subsequent anaerobic digestion, was also investigated. Aerobic thermophilic pretreatment of mixed sludge before anaerobic digestion was able to produce sludge that can meet the following Class A pathogen reduction requirements: fecal coliform density <1 000 MPN/g total solids or Salmonella sp. density <3 MPN/4 g total solids; time and temperature requirements (1.8 hr at 63°C); enteric virus density <1 PFU/4 g total solids; and vector attraction requirement (>38% volatile solids reduction). ATP was able to control Nocardia to below detectable levels, whereas the Nocardia levels in the control anaerobic digester were ≥105 intersections/g VSS when both were fed mixed sludge containing Nocardia filament counts in excess of 105 intersections/g VSS. The ATP system was also able to produce higher volatile solids (VS) reduction, higher methane content in sludge gas, and lower sludge supernatant COD when compared with those achieved in the control anaerobic digester.
Oil recovery at a former wood‐treating facility
Authors: Sale T. C. , Applegate D. H.
Published: October 2006

Pools of mobile dense nonaqueous phase liquids (DNAPL) are often found perched above capillary boundaries at sites where DNAPLs have been managed. An approach to partially address risks posed by pools of mobile DNAPLs is to recover the mobile fraction of the DNAPL and, thereby, limit the potential for future DNAPL migration. During the last 8 yrs, development and implementation of an effective mobile DNAPL recovery technique has been ongoing at a former wood‐treating plant located in Laramie, Wy. The technology relies on dual horizontal water and DNAPL recovery drainlines, installed in a single trench, coupled with parallel single water delivery drainlines. By cycling water between the upper recovery and parallel delivery drainlines, DNAPL is hydraulically driven to the lower recovery drainlines. Presently, full‐scale DNAPL recovery operations at the site are in their fourth year of an approximate 8‐yr program. An area of ∼24 ha is being addressed. To date, ∼4.9 million L of DNAPL has been recovered and an endpoint of 95% recovery of mobile DNAPL is being achieved. Review of this technology's development and implementation provides insight into a unique approach to mobile DNAPL recovery which is likely applicable at other sites.
Monte Carlo assessment of microbial risk associated with landfilling of fecal material
Authors: Haas Charles N. , Anotai Jin , Engelbrecht Richard S.
Published: October 2006

Discarded solid material derived from or soiled with fecal matter is commonly disposed in sanitary landfills. This material includes wastewater solids, pet feces, infectious wastes, and soiled disposable diapers. Such materials may contain indicator organisms, as well as human pathogens, including viruses. The aim of the present work was to analyze the health risk to humans from ingesting untreated groundwater obtained from aquifers subject to contamination from landfills receiving such materials. Uncertainty and variability associated with source composition as well as transport processes were included. It was concluded that, even with conservative assumptions, the health risk to humans from exposure to microbial pathogens of fecal origin deposited in well–designed and operated sanitary landfills is below levels currently considered to be acceptable under U.S. drinking water regulations applicable to treated potable water supplies.
Environmental factors and modeling in microbial chromium (VI) reduction
Authors: Chen Jin M. , Hao Oliver J.
Published: October 2006

A Cr(VI)‐reducing culture was enriched from an anaerobic chemostat fed with synthetic media containing acetate and Cr(VI). The enriched culture was used for a series of batch tests to investigate several environmental factors affecting microbial Cr(VI) reduction. Under carbon‐limiting conditions, the extent of Cr(VI) reduction proportionally depended on the carbon concentration and no reduction of Cr(VI) was observed in the absence of acetate. Cr(VI) reduction was also dependent upon the initial biomass level and the type of organic compounds. The developed model predicted Cr(VI) reduction well at different Cr(VI) concentrations. Sulfate at 120 mg SO42−/L or nitrate at 150 mg N/L slightly inhibited Cr(VI) reduction. Reduction of nitrate but not sulfate was observed along with Cr(VI) reduction. Cr(VI) was not reduced by the aerobically growing culture, and it was found that oxygen inhibitory effects on Cr(VI) reduction were reversible. The optimum pH and temperature for Cr(VI) reduction were found to be 7.3 and 32°C, respectively. In addition, Cr(VI) reduction was sensitive to the metal ions that may coexist with Cr(VI) in industrial wastes containing Cr(VI).
Physical and chemical water requirements of the white‐clawed crayfish (Austropotamobius pallipes) in western France
Authors: Trouilhé Marie‐Cécile , Souty‐Grosset Catherine , Grandjean Frédéric , Parinet Bernard
Published: October 2006

In France, the distribution of the native white‐clawed crayfish (Austropotamobius pallipes) is restricted, fragmented and mainly located in headwater streams. To conserve this indigenous species, it is necessary to characterize its habitat preferences.

Seven brooks in the Deux‐Sèvres Département (western France) containing wild populations of A. pallipes were studied to determine its ranges of tolerance to 19 physical and chemical water parameters. On two brooks, the Sèvre Nantaise and the Verdonnière, sites with and without A. pallipes were compared. Each site was sampled twice monthly from November 2002 to November 2004.

It was found that the white‐clawed crayfish was able to tolerate wide ranges of values of some of the measured parameters. The Magot site harboured the largest A. pallipes population (17.5 crayfish m−2) and had dissolved oxygen concentrations as low as 4.93 mg L−1, while water temperature rose above 20°C for several consecutive days during summer and nitrate concentrations were always found to be above 30 mg L−1. These unusual findings could call into question the status of A. pallipes as a bioindicator of good water quality.

Principal component analyses (PCA) suggested that an increase of organic matter was a discriminant factor for the presence or absence of A. pallipes. In addition, sites with and without crayfish on the Sèvre Nantaise brook showed showed significant differences (p<0.05) in total organic carbon (TOC), and those on the Verdonnière brook in turbidity and total suspended solids (TSS).

Copyright © 2006 John Wiley & Sons, Ltd.
Stage migration caused by D2 dissection with para-aortic lymphadenectomy for gastric cancer from the results of a prospective randomized controlled trial
Authors:   Gastric Cancer Surgical Study Group of the Japan Clinical Oncology Group, Yoshikawa T , Sasako M , Sano T , Nashimoto A , Kurita A , Tsujinaka T , Tanigawa N , Yamamoto S
Published: October 2006

Background

Extended lymphadenectomy (D2) provides accurate nodal staging of gastric cancer. The aim of this study was to clarify the degree of stage migration seen with D2 combined with para-aortic lymph node dissection for gastric cancer invading the subserosa, the serosa and adjacent structures (T2ss–4) in patients considered not to have distant metastases (M0).

Methods

Between July 1995 and April 2001, 523 patients were recruited and randomized in a prospective phase III trial comparing D2 with D2 and para-aortic nodal dissection for T2ss–4 gastric cancer without macroscopic para-aortic nodal metastases. Stage migration was evaluated by Japanese Gastric Cancer Association staging in 260 patients who underwent D2 with para-aortic dissection by analysing pathological information from the dissected lymph nodes.

Results

Node (N)-stage migration was observed in 1 per cent (1 of 82) of patients with N1 disease, 20 per cent (12 of 59) with N2, 43 per cent (10 of 23) with N3 and 8·8 per cent (23 of 260) of all patients. Final stage migration occurred in 9 per cent (5 of 58) of patients with stage IIIa, 19 per cent (8 of 42) with stage IIIb, 56 per cent (9 of 16) with stage IVa and 8·5 per cent (22 of 260) of all patients. Metastasis to N4 nodes was found in 4 per cent (four of 95) of tumours invading the subserosa and 17·4 per cent (19 of 109) of tumours penetrating the serosa. The overall incidence of N4 involvement was 8·8 per cent (23 of 260).

Conclusion

Extended para-aortic lymphadenectomy for gastric cancer provides accurate nodal staging and results in stage migration, which may improve stage-specific survival regardless of overall survival benefit.
In Situ Fabrication of Cross‐Linked Protein Membranes by Using Microfluidics
Authors: Nair Greeshma , Gargiuli Joseph F. , Shiju N. Raveendran , Rong Zimei , Shapiro Evgeniy , Drikakis Dimitris , Vadgama Pankaj
Published: October 2006

We report a novel technique for preparing cross‐linked protein membranes within microchannels by using an interfacial cross‐linking reaction. Glass microchannels with a Y input were assembled by using a simple adhesive bonding technique to achieve dual, parallel laminar flows. Membrane formation utilised an interfacial reaction at the liquid–liquid interface, which involved bovine serum albumin (aqueous solution with a flow rate of 300 μL min−1) and terephthaloyl chloride (xylene solution with a flow rate of 700 μL min−1), to form thin (∼25 μm) cross‐linked films along the length of the channel under the continuous pressure‐driven laminar flow. Such microfabricated membranes could extend the separation potential of any microfluidic structure to provide a stable barrier layer. Furthermore, degradation of the membrane was possible by using an alkali sodium dodecyl sulfate solution, which led to the complete disappearance of the membrane. These membranes could facilitate additional modification to allow for different permeability properties by controlled degradation. The one‐step in situ membrane‐fabrication methodology reported here generated precisely localised membranes and avoided the complexities of subcomponent assembly, which require complicated alignment of small, preformed membranes. This methodology could become the basis for sophisticated microseparation systems, biosensors and several “lab‐on‐a‐chip” devices.
Origin of Informational Polymers: The Concurrent Roles of Formamide and Phosphates
Authors: Saladino Raffaele , Crestini Claudia , Neri Veronica , Ciciriello Fabiana , Costanzo Giovanna , Di Mauro Ernesto
Published: October 2006

Formamide chemistry provides a unitary system by gathering all of the precursors needed to synthesise pregenetic informational polymers in a single milieu. This is not observed with HCN chemistry. With common catalysts, formamide affords all of the precursor nucleobases, photochemically condenses into acyclonucleosides, favours transphosphorylation and enhances micellar aggregation of surfactants. Also, formamide provides a set of physicochemical conditions that thermodynamically favour the polymeric state of nucleotides over the monomers. In the origin‐of‐informational‐polymers scenario, formamide acts in every step, the least characterised being the set of its reactions with phosphates. On this matter, we report two complementary sets of results: 1) the synthesis of prebiotic precursors from formamide, which are catalysed by soluble and mineral phosphates—we observed the formation of rich mixtures that include uracil, 9H‐purine, cytosine, dihydrouracil, hypoxanthine, adenosine, urea, parabanic acid, the amino acid N‐formylglycine and the peptide‐condensing agent carbodiimide; and 2) the protection of ribo‐ and deoxyribophosphoester bonds by phosphates. The relevance of these effects with respect to the origin of informational polymers is discussed.
The Compound 13‐D Selectively Induces Apoptosis in White Blood Cancers versus Other Cancer Cell Types
Authors: Putt Karson S. , Nesterenko Vitaliy , Dothager Robin S. , Hergenrother Paul J.
Published: October 2006

As general cytotoxins are still the backbone of anticancer chemotherapy, the identification of selective inducers of cell death in defined cancer types and subtypes is one of the major goals of modern oncology research. Thus, compounds identified with such selectivity have utility as probes of cancer‐type‐specific biological pathways, and optimized versions have potential in targeted anticancer therapy. Described herein is the discovery that compound 13‐D selectively induces apoptotic cell death in white blood cancer cell lines but not in other cancer cell lines. Further experiments indicate that this selectivity is not simply due to selective cell permeability. The compound localizes to both the nucleus and cytoplasm and arrests cells in the prophase/prometaphase of the cell cycle, and there is a very sharp dependence of activity on compound structure, with the trans‐α,β‐unsaturated amide of 13‐D being critical for inducing cell death. The macromolecular target of 13‐D could be involved in white blood cell‐specific oncogenic pathways.
Cover Picture: Molecular Recognition: Preorganization of a Bis(pyrrole) Schiff Base Derivative for Tight Dimerization by Hydrogen Bonding (Chem. Eur. J. 31/2006)
Authors: Munro Orde Q. , Joubert Sandra D. , Grimmer Craig D.
Published: October 2006

Molecular recognition through conformational preorganization is discussed in the Full Paper on page 7987 ff. by O. Q. Munro et al. The global minimum conformation of a bis(pyrrole) Schiff base derivative exhibits C2 symmetry and a highly nonplanar conformation that is preorganized for self‐assembly into a tight hydrogen‐bonded dimer with exact D2 symmetry. The solution‐phase structure of the dimer, which predominates at higher concentrations (narrow pyrrole NH resonance), matches the X‐ray structure. The monomers within the dimer are electronically mixed.
Inflammatory breast cancer outcome with epirubicin‐based induction and maintenance chemotherapy
Authors: Veyret Corinne , Levy Christelle , Chollet Philippe , Merrouche Yacine , Roche Henri , Kerbrat Pierre , Fumoleau Pierre , Fargeot Pierre , Clavere Pierre , Chevallier Bernard
Published: October 2006

BACKGROUND.

The authors evaluated the long‐term efficacy and side effects in patients with nonmetastatic, unilateral, inflammatory breast cancer (IBC) who received homogeneous treatment with intensive induction chemotherapy followed by a maintenance regimen.

METHODS.

One hundred twenty patients were randomized to receive high‐dose fluorouracil, epirubicin, and cyclophosphamide (FEC‐HD) (fluorouracil 750 mg/m2on Days 1 to 4, epirubicin 35 mg/m2on Days 2 to 4, and cyclophosphamide 400 mg/m2on Days 2 to 4 for 4 cycles every 21 days) with or without lenograstim. Locoregional treatment consisted of surgery and/or radiotherapy. Maintenance chemotherapy was FEC 75 (fluorouracil 500 mg/m2, epirubicin 75 mg/m2, and cyclophosphamide 500 mg/m2on Day 1 every 21 days for 4 cycles). No hormone treatment was allowed.

RESULTS.

The safety of the FEC‐HD regimen was described previously. Among 102 patients who underwent surgery, a pathologic complete response (pCR) was achieved by 23.5% of patients with breast tumors and by 31.4% of patients with involved axillary lymph nodes. The overall pCR rate was 14.7%. One hundred nine patients received FEC 75. After a median 10 years of follow‐up, the disease‐free survival (DFS) and overall survival (OS) rates were 35.7% and 41.2%, respectively. The median DFS was 39 months (95% confidence interval [95% CI], 25–53 months), and the median survival was 61 months (95% CI, 43–79 months). Five patients developed a temporary decrease in left ventricular ejection fraction without congestive heart failure. In the lenograstim group, 1 patient developed acute myeloblastic leukemia M2, and 1 patient developed myelodysplastic syndrome.

CONCLUSIONS.

FEC‐HD induction chemotherapy followed by FEC 75 maintenance regimen had moderate and acute long‐term toxicities and lead to high DFS and OS rates in patients with IBC. Cancer 2006. © 2006 American Cancer Society.
Computing eigenvalue bounds of structures with uncertain‐but‐non‐random parameters by a method based on perturbation theory
Authors: Leng Huinan , He Zhiqing
Published: October 2006

In this paper, an eigenvalue problem that involves uncertain‐but‐non‐random parameters is discussed. A new method is developed to evaluate the reliable upper and lower bounds on frequencies of structures for these problems. In this method the matrix in the deviation amplitude interval is considered to be a perturbation around the nominal value of the interval matrix, and the upper and lower bounds to the maximum and minimum eigenvalues of this perturbation matrix are computed, respectively. Then based on the matrix perturbation theory, the eigenvalue bounds of the original interval eigenvalue problem can be obtained. Finally, two numerical examples are provided and the results show that the proposed method is reliable and efficient. Copyright © 2006 John Wiley & Sons, Ltd.
Optical Properties of Zinc Oxide Nanoparticles and Nanorods Synthesized Using an Organometallic Method
Authors: Kahn Myrtil L. , Cardinal Thierry , Bousquet Bruno , Monge Miguel , Jubera Véronique , Chaudret Bruno
Published: October 2006

The emission properties of nanocrystalline ZnO particles prepared following an organometallic synthetic method are investigated. Spherical particles and nanorods are studied. The shape of the particles and the ligands used are shown to influence the luminescence properties in the visible domain. Two different emissions are observed at 440 nm (≈2.82 eV) and at 580 nm (≈2.14 eV) that are associated with the presence of surface defects on the particles. The first emission corresponds to the well‐known yellow emission located at 580 nm (≈2.14 eV) with a lifetime of 1850 ns for 4.0 nm size ZnO nanoparticles. The second emission at 440 nm (≈2.82 eV) is observed when amine functions are present. This strong blue emission is associated with an excitation energy less than that associated with the yellow emission displaying a lifetime of nine nanoseconds. A possible hole trapping effect by the amine groups on the surface of the ZnO particles is discussed as the origin of this emission. The modification of the intensities between the two visible emissions for different particle shapes is proposed to be related to a specific location of the amine ligands on the surface of the particles.
Designer T cells by T cell receptor replacement
Authors: Sommermeyer Daniel , Neudorfer Julia , Weinhold Monika , Leisegang Matthias , Engels Boris , Noessner Elfriede , Heemskerk Mirjam H. M. , Charo Jehad , Schendel Dolores J. , Blankenstein Thomas , Bernhard Helga , Uckert Wolfgang
Published: October 2006

T cell receptor (TCR) gene transfer is a convenient method to produce antigen‐specific T cells for adoptive therapy. However, the expression of two TCR in T cells could impair their function or cause unwanted effects by mixed TCR heterodimers. With five different TCR and four different T cells, either mouse or human, we show that some TCR are strong – in terms of cell surface expression – and replace weak TCR on the cell surface, resulting in exchange of antigen specificity. Two strong TCR are co‐expressed. A mouse TCR replaces human TCR on human T cells. Even though it is still poorly understood why some TCRα/β combinations are preferentially expressed on T cells, our data suggest that, in the future, designer T cells with exclusive tumor reactivity can be generated by T cell engineering.
Coordination Chemistry of 3‐Mercapto‐2‐(mercaptomethyl)propanoic Acid (Dihydroasparagusic Acid) with Iron and Nickel
Authors: Volkers Phillip I. , Rauchfuss Thomas B. , Wilson Scott R.
Published: October 2006

The first transition‐metal complexes bearing the natural product dihydroasparagusic acid, (HSCH2)2CHCO2H, as a ligand are reported. Various coordination modes and nuclearities are demonstrated for the chelating ligand by a series of iron and nickel complexes. Fe2[(SCH2)2CHCO2H](CO)6 retains carbonyl substitution reactivity typical of Fe2(SR)2(CO)6 complexes, yet carboxy coordination to FeI was unobserved. Coupling of the carboxylic acid with amines yields the corresponding amides Fe2[(SCH2)2CHC(O)NHR](CO)6 (R = Et, gly–O–tBu). Fe2[(SCH2)2CHCO2H](CO)4(PMe3)2 catalyzes H2 production, but no better than unfunctionalized alkyl dithiolate analogs. Reactions of the ligand with NiCl2(dppe) afforded mono‐, di‐, and trinuclear complexes. Noteworthy is Ni3[(SCH2)2CHCO2]2(dppe)2, which features an octahedrally coordinated NiII center linked to a pair of square‐planar NiII centers. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
A DFT Study on the Electronic and Redox Properties of [PW11O39(ReN)]n–(n = 3, 4, 5) and [PW11O39(OsN)]2–
Authors: Yan Li‐Kai , Dou Zhuo , Guan Wei , Shi Shao‐Qing , Su Zhong‐Min
Published: October 2006

DFT calculations were carried out to investigate the electronic and redox properties of nitrido‐functionalized polyoxometalate species, [PW11O39(ReN)]n– (n = 3, 4, 5) and [PW11O39(OsN)]2–. The rhenium‐ and osmium‐nitrido effectively modify the electronic properties. The LUMOs in fully oxidized [PW11O39(ReN)]3– and [PW11O39(OsN)]2– are mainly concentrated on the Re and Os centers. The high‐valent transition metals Re and Os modify the components and energies of the LUMO. The LUMO energies of [PW11O39(ReN)]3– and [PW11O39(OsN)]2– are lower than that of related Keggin [PW12O40]3–. In addition, Re centers will prefer to accept the electrons in the first and second reduced process of fully oxidized [PW11O39(ReN)]3–. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Diastereoselective Synthesis of Conformationally Restricted Dinucleotides Featuring Canonical and Noncanonical α/β Torsion Angle Combinations(α,β‐D‐CNA)
Authors: Dupouy Christelle , Le Clézio Ingrid , Lavedan Pierre , Gornitzka Heinz , Escudier Jean‐Marc , Vigroux Alain
Published: October 2006

The synthesis of the four possible diastereoisomers of α,β‐D‐CNA 5′‐XT (X = A, T, G and C) building units of nucleic acids, in which the α and β torsional angles are stereocontrolled by a dioxaphosphorinane ring structure (D‐CNA family) is described. The crystal structure analysis of the (RC5′,SP)‐configured α,β‐D‐CNA TT dimer demonstrates that the α and β torsional angles are restricted to the canonical {gauche(–),trans} conformation typically observed in DNA duplexes. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Voltammetric Behavior of Antileukemia Drug Glivec. Part III: In Situ DNA Oxidative Damage by the Glivec Electrochemical Metabolite
Authors: Diculescu Victor Constantin , Vivan Marilene , Brett Ana Maria Oliveira
Published: October 2006

Glivec is a relatively small molecule with activity against the protein tyrosine kinase, a protein expressed by all patients with chronic myelogenous leukemia (CML). Based on its activity on CML, glivec is undergoing extensive evaluation of its activity against other types of tumor. As a result, there is an ongoing need for clarification of glivec pharmacokinetics so that issues such as drug‐biomolecular complex interactions can be understood.
Electrochemical Detection of Short DNA Oligomer Hybridization Using the CombiMatrix ElectraSense Microarray Reader
Authors: Roth Kristian M. , Peyvan Kia , Schwarzkopf Kevin R. , Ghindilis Andrei
Published: October 2006

A microarray reader named ElectraSense using an electrochemical detection technique has been developed for the CombiMatrix CustomArray 12 544 electrode semiconductor DNA microarray. The detection is based on electrochemical reduction of the enzymatic oxidization product of 3,3′,5,5′‐tetramethylbenzidene (TMB). TMB oxidation is catalyzed by a horseradish peroxidase (HRP) biomarker linked to a DNA target molecule through biotin‐avidin chemistry. Electrochemical signal collection is performed by a computer controlled combinatorial semiconductor addressing instrument. Electrode to electrode switching can be accomplished in hundreds of microseconds and a detection time for each electrode is less than 5 ms. The whole array detection requires less than 60 s. Numerous parameters of the measurement procedure have been optimized and assay performance has been studied and a method for array quality control has been developed. Application of electrochemical detection of Combimatrix microarrays has been demonstrated for DNA detection over 4 orders of magnitude of target concentrations and detection of avian influenza subtype H5N1.
Electrochemical and Sensorial Behavior of SOD Mutants Immobilized on Gold Electrodes in Aqueous/Organic Solvent Mixtures
Authors: Kapp A. , Beissenhirtz M. K. , Geyer F. , Scheller F. , Viezzoli M. S. , Lisdat F.
Published: October 2006

A cysteine mutant of a monomeric human Cu, Zn‐SOD (Glycine 61, Serine 142) has been immobilized directly on gold electrodes using the thiol groups introduced. The electrochemical behavior of the surface confined protein was studied in mixtures of aqueous buffer and DMSO up to an organic solvent content of 60%. The formal potential was found to be rather independent of the DMSO content. However, half peak width increased and the redoxactive amount clearly decreased with raising DMSO content. In addition, the kinetics of the heterogeneous electron transfer became slower; but still a quasireversible electrochemical conversion of the mutant SOD was feasible. Thus, the electrodes were applied for sensorial superoxide detection. At a potential of +220 mV vs. Ag/AgCl advantage was taken of the partial oxidation reaction of the enzyme. A defined superoxide signal was obtained in solutions up to 40% DMSO. The sensitivity of the mutant electrodes decreased linearly with the organic solvent content in solution but was still higher compared to conventional cyt.c based sensors. At DMSO concentrations higher than 40% no sensor response was detected.
Miniature Biofuel Cells with Improved Stability Under Continuous Operation
Authors: Fischback Michael B. , Youn Jong Kyu , Zhao Xueyan , Wang Ping , Park Hyun Gyu , Chang Ho Nam , Kim Jungbae , Ha Su
Published: October 2006

We have developed miniature biofuel cells (BFCs) with dimensions as small as 12×12×9 mm by adopting the design of stackable proton exchange membrane (PEM) fuel cells. The enzymatic anodes were constructed by using stabilized glucose oxidase (GOx) in the form of crosslinked enzyme clusters (CECs) on the surface of carbon nanotubes (CNTs). The combination of stabilized GOx and unbuffered fuel solution resulted in stabilized performance of miniature BFCs under continuous operation for more than 16 hours. This unprecedentedly high operational stability of miniature BFCs opens up new possibilities for many BFC applications.
Dielectrophoretic investigation of plant virus particles: Cow Pea Mosaic Virus and Tobacco Mosaic Virus
Authors: Ermolina Irina , Milner Joel , Morgan Hywel
Published: October 2006

This paper reports experimental results on the dielectrophoretic (DEP) behaviour on two nonenveloped plant viruses of different geometrical shapes, namely Cow Pea Mosaic Virus (CPMV) and Tobacco Mosaic Virus (TMV). The DEP properties of carboxy‐modified latex beads of the same size are also reported. The DEP properties of single particles were obtained from measurement of the frequency at which the DEP force on a particle goes to zero (the crossover frequency). The DEP behaviour of particle ensembles was also measured using image processing. The dielectric properties of the particles were evaluated from the DEP data. The surface conductance was found to be 0.3 nS for CPMV, 0.38 nS for TMV, and 0.52 nS for 27 nm diameter carboxy–latex beads. Data analysis has shown that the optimal condition for separation of TMV and CPMV is a low‐conductivity suspending medium – below 1 mS/m.
Divide and conquer: Rat liver tissue proteomics based on the analysis of purified constituents
Authors: Teufelhofer Olga , Parzefall Wolfram , Elbling Leonilla , Kainzbauer Eveline , Grasl‐Kraupp Bettina , Zielinski Christoph , Schulte‐Hermann Rolf , Gerner Christopher
Published: October 2006

Comparative proteome data of normal and diseased tissue samples are difficult to interpret. Proteins detected in tissues are derived from different cell types and blood constituents. Pathologic or toxicant‐induced aberrations may affect the proteome profile of tissues in several ways since different cell types may respond in very different and highly specific manners. The aim of this study was to analyze the proteome profiles of purified rat liver primary cells and of blood plasma in comparison to liver whole tissue. Moreover, we investigated alterations of these profiles induced by the liver toxicant N‐nitrosomorpholine (NNM) used as a model compound. Whole liver samples, pure hepatocytes and Kupffer cells as well as blood plasma were obtained from saline‐ or NNM‐treated rats. Proteins were separated by 2‐D PAGE and their amounts were estimated by fluorography. Selected proteins were identified by MS analysis of tryptic digests. Among them we identified proteins exclusively expressed in the analysed constituents. Several of these proteins were assigned in the proteome profile of whole‐tissue homogenates. Furthermore, we identified several proteins that were modified, up‐regulated or down‐regulated due to NNM treatment in total liver homogenates. Some of these protein alterations were specifically detected in primary cells isolated from NNM‐treated rats. Thus, we demonstrated the successful assignment of NNM‐induced proteome alterations in rat liver to the cell type of origin. The currently applied approach may help to better understand pathologic processes at a whole‐tissue level.
Estimation of the composition of recombinant human erythropoietin mixtures using capillary electrophoresis and multivariate calibration methods
Authors: Benavente Fernando , Giménez Estela , Olivieri Alejandro C. , Barbosa José , Sanz‐Nebot Victoria
Published: October 2006

A multivariate calibration method using partial least‐squares (PLS) is proposed in order to characterize binary mixtures of two types of recombinant human erythropoietin (epoetin alpha and beta), based on the analysis of the highly overlapped UV‐electrophoretic profiles obtained with the CE methodology recommended by the European Pharmacopoeia (EurPh). A two‐factor PLS‐1 model was developed and validated using mixtures of alpha and beta epoetins. Glycoforms were identified according to their effective electrophoretic mobility values and the normalized area values of each glycoform peak were used as multivariate data. Calibration and validation results were satisfactory. The PLS‐1 model was successfully used for determination of epoetin alpha and beta contents in the rHuEPO provided by the EurPh as a biological reference product.
A methodology for the graphical determination of operating conditions of chromatographic sequences incorporating the trade‐offs between purity and yield
Authors: Salisbury Rebecca S. , Bracewell Daniel G , Titchener‐Hooker Nigel J
Published: October 2006

Multiple‐step chromatography sequences are necessary in biopharmaceutical downstream processing to achieve the desired levels of purity for products such as therapeutic proteins. Traditional methods of process design deal with each step individually, but this can result in a sequence that does not achieve best overall performance. This paper proposes a graphical methodology for the identification of operating conditions for a two‐step chromatography sequence. The method uses windows of operation to incorporate the trade‐offs between yield, purity and productivity. A tie‐line procedure is developed that separates the window of operation for the first chromatographic step into two zones. One zone contains those operating conditions that combine to produce a material which can be purified successfully by the second step to produce a product that meets the desired specifications. The second zone consists of operating conditions which will not yield a material that can be adequately purified by a second chromatographic stage to yield a product of the predetermined specifications. The methodology is valuable in that it helps in achieving the rapid design of a two‐step chromatography sequence, and aids in choosing the optimum operating conditions for the first step that are highly dependent upon the operation and specifications of the second chromatographic step. Simulations carried out using a software package based on the general rate model depict the construction and use of the method applied to a sequence of ion exchange and hydrophobic interaction chromatography separating a three‐component protein mixture. Copyright © 2006 Society of Chemical Industry
An OriP/EBNA‐1‐based baculovirus vector with prolonged and enhanced transgene expression
Authors: Shan Liang , Wang Leyao , Yin Juan , Zhong Peng , Zhong Jiang
Published: October 2006

Background

The baculovirus Autographa californica multiple nucleopolyhedrovirus (AcMNPV) has been explored as a gene delivery vehicle for a variety of mammalian cell lines. However, the transient expression nature due to its incapability to replicate in mammalian cells and insufficient transduction efficiency limit its application.

Methods

Recombinant baculovirus vectors containing genetic elements from Epstein‐Barr virus (EBV), OriP and EBNA‐1, which are essential for the episomal maintenance of the EBV genome in latently infected cells, were constructed and tested for their ability to sustain and express transgene (enhanced green fluorescence protein (egfp)) in mammalian cells.

Results

The recombinant baculovirus containing OriP and EBNA‐1 genes driven by the cytomegalovirus (CMV) promoter was capable of persisting in a significant proportion of infected mammalian cells, HEK293, Vero, Cos‐7, and Hone‐1, without any selective pressure. In HEK293, the expression of EGFP lasted for 60 days with markedly enhanced expression level. The persistence of baculovirus genome correlated with the expression of EBNA‐1.

Conclusions

The improved baculovirus vector could mediate prolonged and enhanced foreign gene expression in some mammalian cells. Furthermore, an adequate level of the EBNA‐1 protein was essential for the maintenance of the OriP‐containing baculovirus genome. The new vector has potential for use in gene therapy. Copyright © 2006 John Wiley & Sons, Ltd.
In vitro study comparing two collageneous membranes in view of their clinical application for rotator cuff tendon regeneration
Authors: Fini Milena , Torricelli Paola , Giavaresi Gianluca , Rotini Roberto , Castagna Alessandro , Giardino Roberto
Published: October 2006

Tenocytes were isolated from the rotator cuff tendons of healthy (HT) and glucocorticoid (GC)‐treated rats (GCT) and were cultured on polystyrene wells (TCP) as control, and on 2 de‐cellularized collagen matrices: porcine small intestinal submucosa (SIS), and human dermal matrix (Graftjacket®, GJ). At 3 and 7 days cell proliferation and synthesis were evaluated. Proliferation of HT tenocytes increased between experimental times for both tested membranes, but already at 3 days, HT tenocytes cultured on GJ showed the highest WST‐1 value. The collagen‐I (CICP) synthesis on GJ membrane did not change between experimental times and was significantly higher than TCP and SIS at 7 days. Proteoglycans (PG), and fibronectin (FBN) synthesis increased when HT were cultured on GJ, between experimental times, and both PG and FBN synthesis on GJ membrane were higher than TCP and SIS at 7 days. GC determined decreases in cell proliferation, CICP and PG syntheses at 3 days of culture on TCP when compared to HT tenocytes while a decrease in WST‐1 was maintained at 7 days. CICP, PG and FBN (only at 3 days) syntheses were significantly higher in GCT tenocytes cultured on GJ. The negative effects on GC on GCT tenocytes cultured on membrane were particularly evident on SIS for CICP (−18%) and FBN (−67%) synthesis. The obtained results support the conclusion that GJ is more suitable than SIS as a scaffold for in situ tissue engineering and for the in vitro bioengineering of tendons to heal massive tears of the rotator cuff tendon. © 2006 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:98–107, 2007
Hypocholesterolaemic and antioxidant effects of Glycyrrhiza glabra (Linn) in rats
Authors: Visavadiya Nishant P. , Narasimhacharya Amaravadi V. R. L.
Published: October 2006

The hypocholesterolaemic and antioxidant effects of Glycyrrhiza glabra (GG) root powder were examined in hypercholesterolaemic male albino rats. A 4‐week administration of GG root powder (5 and 10 gm% in diet) to hypercholesterolaemic rats resulted in significant reduction in plasma, hepatic total lipids, cholesterol, triglycerides and plasma low‐density lipoprotein and VLDL‐cholesterol accompanied by significant increases in HDL‐cholesterol levels. Furthermore, significant increases in fecal cholesterol, neutral sterols and bile acid excretion along with an increase in hepatic HMG‐CoA reductase activity and bile acid production were observed in these animals. The root powder administration to hypercholesterolaemic rats also decreased hepatic lipid peroxidation with a concomitant increase in superoxide dismutase (SOD) and catalase activities and total ascorbic acid content. Thus, the hypocholesterolaemic and antioxidant effects of GG root appeared to be mediated via (i) accelerated cholesterol, neutral sterol and bile acid elimination through fecal matter with an increased hepatic bile acid production and (ii) improving the activities of hepatic SOD, catalase and increasing the ascorbic acid content. The normo‐cholesterolaemic animals when fed with GG root powder at 10 gm% level, registered a significant decline in plasma lipid profiles and an increase in HDL‐cholesterol content. The antioxidant status of these animals also was improved upon treatment.