bluuebunny/crossref_metadata_2025 huggingface dataset:
Surgical reduction and stabilization for repair of femoral capital physeal fractures in cats: 13 cases (1998–2002)
Authors: Fischer Howard R. , Norton Jeffrey , Kobluk Calvin N. , Reed Ann L. , Rooks Robert L. , Borostyankoi Frank
Published: January 2006

Objective—To evaluate anatomic reduction and surgical stabilization of femoral capital physeal fractures in cats.

Design—Retrospective study.

Animals—13 cats.

Procedure—Medical records of cats with unilateral or bilateral femoral capital physeal fractures evaluated from 1998 to 2002 were reviewed. Age and weight of cats at the time of surgery; breed; sex; concurrent injuries; severity of lameness before and 1, 2, 4, 6, and 8 weeks after surgery; the amount of fracture reduction achieved and number of Kirschner wires (K-wires) used; degree of degenerative joint disease of the hip joint and lysis of the femoral neck and head observed after surgery; whether K-wires were removed after surgery; and complications after surgery were evaluated.

Results—Thirteen cats with 16 capital physeal fractures were identified. There was significant improvement in the severity of clinical lameness in all cats from weeks 1 through 4 after surgery. There was no correlation between the scores of the individuals who evaluated radiographs for fracture reduction and placement of K-wires.

Conclusions and Clinical Relevance—Results suggested that surgical stabilization and repair of femoral capital physeal fractures facilitate a short recovery period and a good prognosis for return to normal function in cats. (J Am Vet Med Assoc2004;224:1478–1482)
Comparison of direct immunofluorescence, modified acid-fast staining, and enzyme immunoassay techniques for detection of Cryptosporidium spp in naturally exposed kittens
Authors: Marks Stanley L. , Hanson Timothy E. , Melli Ann C.
Published: January 2006

Objective—To evaluate a modified Ziehl-Neelsen
acid-fast staining technique (mZN), a direct immunofluorescence
detection procedure (DIF), and 3 commercial
enzyme immunoassays (EIAs) for detection of
Cryptosporidium oocysts in fecal specimens from kittens.

Design—Prospective study.

Sample Population—416 fecal specimens collected
from 104 randomly selected domestic shorthair kittens
(8 to 16 weeks of age) that were naturally
exposed to Cryptosporidium spp.

Procedure—Fresh fecal specimens were collected
once daily for 4 consecutive days and processed
immediately. Sensitivities of mZN, DIF, and 3 commercial
EIAs (EIA-1, EIA-2, and EIA-3) were estimated
and compared.

Results—EIA-2 had the highest sensitivity on day 1
(89%), followed by EIA-1 (80%), and mZN (72%). EIA-
3 had the lowest sensitivity on day 1 (15%). EIA-2, EIA-
1, and mZN had similar sensitivities after 2 consecutive
fecal examinations (approx 90%). Determination of
specificities was compromised by the small number of
cats that had negative results for all tests (n = 3).

Conclusions and Clinical Relevance—Results suggest
that EIA-2 and EIA-1 had the highest sensitivities
when only a single fecal specimen was examined;
however, mZN and EIA-1 had similar sensitivities
when 2 consecutive fecal specimens were examined.
The higher costs of EIA-2 and EIA-1 may be offset by
the tests’ high sensitivity, simplicity of use, and ease
of interpretation and by savings in technician time.
(J Am Vet Med Assoc 2004;225:1549–1553)
Prevalence of Salmonella spp on conventional and organic dairy farms
Authors: Fossler Charles P. , Wells Scott J. , Kaneene John B. , Ruegg Pamela L. , Warnick Lorin D. , Bender Jeffrey B. , Godden Sandra M. , Halbert Lisa W. , Campbell Amy M. , Zwald Angela M. Geiger
Published: January 2006

Objective—To describe the occurrence of fecal shedding, persistence of shedding over time, and serogroup classification ofSalmonellaspp on a large number of dairy farms of various sizes.

Design—Longitudinal study.

Sample Population—22,417 fecal samples from cattle and 4,570 samples from the farm environment on 110 organic and conventional dairy farms in Minnesota, Wisconsin, Michigan, and New York.

Procedure—5 visits were made to each farm at 2-month intervals from August 2000 to October 2001. Fecal samples from healthy cows, calves, and other targeted cattle groups and samples from bulk tank milk, milk line filters, water, feed sources, and pen floors were collected at each visit. Bacterial culture was performed at 1 laboratory.

Results—Salmonellaspp were isolated from 4.8% of fecal samples and 5.9% of environmental samples; 92.7% of farms had at least 1Salmonella-positive sample. The 75th percentile for median within-herd prevalence ofSalmonellaspp in cattle for 5 sampling visits to a given farm was 2.0% and for maximum within-herd prevalence ofSalmonellaspp was 13.6%. Farms with a median within-herd prevalence ofSalmonellaspp of ≥ 2.0% accounted for 76.3% ofSalmonella-positive samples. There was no significant difference in the prevalence ofSalmonellaspp between conventional and organic farms. Seasonal differences inSalmonellashedding were observed. More farms had at least 1 serogroup B isolate than any other serogroup, whereas serogroup E1 was the most common among allSalmonella-positive samples. More than 1 serogroup was isolated on 76.4% ofSalmonella-positive farms.

Conclusions and Clinical Relevance—Salmonellaspp were isolated from > 90% of dairy farms; however, 25% of farms accounted for > 75% ofSalmonella-positive samples. This information is critical for the direction of intervention strategies to decrease the prevalence ofSalmonellaspp on dairy farms. (J Am Vet Med Assoc2004;225:567–573)
Underlying cause, pathophysiologic abnormalities, and response to treatment in cats with septic peritonitis: 51 cases (1990–2001)
Authors: Costello Merilee F. , Drobatz Kenneth J. , Aronson Lillian R. , King Lesley G.
Published: January 2006

Objective—To determine the underlying cause, pathophysiologic abnormalities, and response to treatment in cats with septic peritonitis and identify differences between cats that survived following treatment and cats that did not survive despite treatment.

Design—Retrospective study.

Animals—51 cats with septic peritonitis.

Procedure—Medical records were reviewed for clinical findings; results of clinicopathologic testing, microbial culture, and radiography; diagnosis; treatment; and outcome.

Results—Signs of pain during palpation of the abdomen were reported for only 29 of 47 (62%) cats. Eight (16%) cats had relative bradycardia (heart rate < 140 beats/min). The most commonly isolated organisms includedEscherichia coli, Enterococcusspp, andClostridiumspp. The most common cause of peritonitis was gastrointestinal tract leakage (24 cats). No definitive source could be identified in 7 cats. Treatment, including exploratory surgery, was pursued in 23 cats, of which 16 (70%) survived and were discharged. There were no significant differences between survivors and nonsurvivors in regard to heart rate, age, rectal temperature, serum lactate concentration, WBC count, PCV, blood glucose concentration, or serum albumin concentration.

Conclusions and Clinical Relevance—Results suggest that clinicopathologic abnormalities and outcome in cats with septic peritonitis are similar to those reported for dogs. However, certain features may be unique, including an absence of signs of pain during abdominal palpation, relative bradycardia, and apparent spontaneous peritonitis in some cats. (J Am Vet Med Assoc2004;225:897–902)
Minimum switching control for adaptive tracking
Authors: Fu Minyue
Published: January 2006

The switching adaptive control method has been used for quite a few years to solve the adaptive stabilization and model reference adaptive control problems. However, a serious problem with the switching control method is that the number of ‘candidate’ controllers can potentially be very large, especially for multi‐input–multi‐output systems. In this paper, we consider a class of minimum‐phase multi‐input–multi‐output plants with some mild compactness assumptions. Given any polynomial reference input, we provide a switching control law which guarantees exponentially stability of the closed‐loop system with exponential tracking performance. The main contribution of the paper is that we give the minimum number of candidate controllers required for switching. In particular, the number is equal to 2 for single‐input–single‐output plants (one for each sign of the high‐frequency gain), and is equal to 2mform‐input–m‐output plants. That is, the number is independent of the degree and the relative degree of the plant. Copyright © 2006 John Wiley & Sons, Ltd.
Flotation Separation and Electrothermal Atomic Absorption Spectrometric Determination of Thallium in Wastewater Samples
Authors: Hosseini Mohammad Saeid , Chamsaz Mahmoud , Raissi Heidar , Naseri Yousef
Published: January 2006

The proposed method is a simple process for the determination of trace amount of thallium(I) in the environmental wastewater samples by electrothermal atomic absorption spectrometry. The wastewater samples were obtained from the environment of a cement plant and subjected to a simple treatment, such as adjusting pH and masking the interfering ions, to prepare for the flotation process in which the thallium(I) content was floated as an ion‐association complex using iodide and Rhodamine B at the interface of aqueous/cyclohexane layers. The floated layer was then separated and dissolved in 2 ml of a solution, which was 1 % to H2SO4 and 50 % to methanol, respectively. Aliquots of 10‐μl of this solution were subjected to the graphite furnace to determine the thallium(I) content. The flotation process can be carried in a weak acidic medium in which the interfering effects owing to certain metal ions were eliminated by masking them as neutral citrate chelates. The dynamic range for the determination was found to be 1.0×10‐8 ‐ 1.0×10‐7 mol l‐1. The RSD was 3.2 % and the DL was 2.5×10‐9 mol l‐1 (calculated as 3SD of the blank). The reliability of the method is demonstrated by the analysis of a synthetic wastewater in which the recovery was found to be 94 %.
Separation and Determination of Isoflavonoids in Several Kudzu Samples by High‐Performance Capillary Electrophoresis (HPCE)
Authors: Fang Congbing , Wan Xiaochun , Tan Huarong , Jiang Changjun
Published: January 2006

Pueraria lobata is a rich source of isoflavonoids. The detection and identification of isoflavonoid components from root, stem, leaf, callus and cell samples, is very important for the best, safest and most efficacious use of kudzu as a medicinal plant, and for the studies on quantitative analysis in the secondary metabolism of isoflavonoids. In this paper, a simple, rapid and precise high‐performance capillary electrophoresis (HPCE) method with diode array detection (DAD) has been developed for separation and determination of isoflavonoids in several kudzu samples. The isoflavonoids could be well separated within 15 min in a 40 cm length capillary at a separation voltage of 15kV in a 30mmol L‐1 borax buffer (pH9.29), and this proposed method demonstrated excellent reproducibility and accuracy with relative standard deviations of less than 5 % for isoflavonoid content (n = 5) of different kudzu samples. The relationship between peak areas and isoflavone concentrations, in a specified working range with linear response, was determined by first‐order polynomial regression over the range 0.05‐0.5 mg mL‐1 for puerarin and 2.5‐50 μg mL‐1 for 3'‐methoxypuerarin, daidzin and daidzein, respectively, and quantitative evaluation of those four main isoflavonoid components was determined by ultraviolet absorption at λ=192 nm. The differences were also illustrated by comparison of the determination of isoflavonoid components from kudzu root, stem, leaf samples and plant tissue cultures in vitro.
A Novel Multipurpose Excel Tool for Equilibrium Speciation Based on Newton‐Raphson Method and on a Hybrid Genetic Algorithm
Authors: del Piero Silvia , Melchior Andrea , Polese Pierluigi , Portanova Roberto , Tolazzi Marilena
Published: January 2006

A new algorithm for simulation of chemical equilibria is developed, based on classical Newton‐Raphson method applied to mass balance. This tool, named EST (Equilibrium Speciation Tool), is improved by using a robust Genetic Algorithm. In addition, EST works by using Excel spreadsheets and therefore offers the innovation of a great simplicity and versatility. In fact, it allows the users to simulate, or to obtain from experimental data, desired chemical‐physical parameters as well as to interact with other available or freely created Excel tools. The reliability of this utility is here proved by comparison with some published data by other authors, concerning both complicated homogeneous and heterogeneous equilibria. In addiction its flexibility is tested computing thermodynamic parameters by using experimental calorimetric data referred to the complex formation of cobalt(II) with a macrocyclic ligand. A brief review and comparison of the relative robustness and quickness of main numerical methods are also reported.
Distribution and Occurence of Polycyclic Aromatic Hydrocarbons (PAHs) in Sediments from the Mar Grande and Gulf of Taranto (Ionian Sea, Southern Italy)
Authors: Cardellicchio Nicola , Buccolieri Alessandro , Giandomenico Santina , Lerario Vito Luigi , Lopez Luigi , Pizzulli Filomena
Published: January 2006

Marine sediments from the Mar Grande and Gulf of Taranto were analysed for 17 parent PAHs, with molecular weight from 128 to 278 Daltons. The analyses were performed by gas chromatography coupled to mass spectrometry (GCMS). Total PAHs content in sediments ranged from 464 to 12522 μg kg−1 dry wt for Mar Grande and from 593 to 72275 μg kg−1 dry wt for Gulf of Taranto. The analytical results were compared with the published results for other coastal areas in the Mediterranean Sea. PAHs levels in the Gulf of Taranto sediments were the highest in the Mediterranean sea, while PAHs concentrations in Mar Grande were higher than the ones reported in the Adriatic and Cretan Sea and with the same order of magnitude of the ones known for coastal areas of the Western and the Eastern Mediterranean Sea. PAHs concentration ratios were consistent with the main source of these compounds, in most areas, being pyrolysis. Based on the comparison of both the individual and the total PAHs concentrations with proposed sediment quality guidelines, the acute biological effects on the marine organisms were probable, especially for the Gulf of Taranto, in which almost all PAHs concentrations in sediments were higher than the guidelines limit values. The statistical analysis effected by HCA and PCA methods was used in order to classify sediment samples and to identify accumulation areas.
Synthesis of N‐hydroxymethyl acrylamide with β‐methyl hydrogen itaconate and itaconic acid hydrogels: Effects of the pH, composition, and ionic strength on the swelling behavior
Authors: Jeria‐Orell M. , Pizarro G. Del C. , Marambio O. G. , Huerta M. , Geckeler K. E.
Published: January 2006

Copolymer gels were prepared by the radical copolymerization of N‐hydroxymethyl acrylamide with itaconic acid and N‐hydroxymethyl acrylamide with β‐methyl hydrogen itaconate. The ratios of both monomers were varied from 25 to 75 mol %, and the effects of external stimuli such as the pH and ionic strength of the swelling media were investigated. The gels were pH‐responsive, and an increase in the ionic strength of the solutions caused a decrease in the equilibrium degree of swelling of the copolymer gels. The monomer reactivity ratios were determined with the Kelen–Tüdös method. Moreover, the copolymer composition had a significant effect on the equilibrium swelling behavior of the two copolymers investigated. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1735–1741, 2006
Synthesis and Antibacterial Activity of 1β‐Methyl‐2‐[5‐(1,2‐Disubstituted Ethyl)Pyrrolidin‐3‐ylthio]Carbapenem Derivatives
Authors: Ahn Soo‐Hyun , Jeon Heechol , Choi Joung‐Hoon , Baek Daejin , Seo Seon Hee , Cho Jung‐Hyuck , Oh Chang‐Hyun
Published: January 2006

The synthesis of a new series of 1β‐methylcarbapenems having a 5‐(1,2‐disubstituted ethyl) pyrrolidine moiety is described. Their in vitro antibacterial activities against both Gram‐positive and Gram‐negative bacteria were tested and the effect of the substituent on the pyrrolidine ring was investigated. A particular compound IIIf having a 1‐methoxyimino‐2‐carbamoylethyl substituted moiety showed the most potent antibacterial activity.
Enhancing recombinant glycoprotein sialylation through CMP‐sialic acid transporter over expression in Chinese hamster ovary cells
Authors: Wong Niki S.C. , Yap Miranda G.S. , Wang Daniel I.C.
Published: January 2006

Glycosylation engineering strategies that are currently used to improve quality of recombinant glycoproteins involve the manipulation of glycosyltransferase and/or glycosidase expression. We explored the possibility that over expressing nucleotide sugar transporters, particularly the CMP‐sialic acid transporter (CMP‐SAT) would improve the sialylation process in Chinese hamster ovary cells (CHO). Our hypothesis was that increasing CMP‐SAT in the cells through recombinant means would increase the transport of CMP‐sialic acid into the Golgi, resulting in an increased CMP‐sialic acid intra‐lumenal pool and increased sialylation of the proteins produced. We report the construction of the CMP‐SAT expression vector (pcDNA‐SAT) using hamster CMP‐SAT (GenBank accession number Y12074) and demonstrated its functionality using Lec2 CHO mutant cells. Transfection of pcDNA‐SAT into CHO IFN‐γ, a CHO cell line producing recombinant human interferon‐gamma (IFN‐γ) resulted in single clones that had 2–20 fold increase in total CMP‐SAT expression at the transcript level and 1.8–2.8 fold increase in CMP‐SAT at the protein level when compared to untransfected parent CHO IFN‐γ. This resulted in 4%–16% increase in site sialylation of IFN‐γ. There was also a higher proportion of the more sialylated IFN‐γ glycans produced by the clones. We have thus established a novel strategy for sialylation improvement in recombinant protein production that can be considered singly or along with existing glycosylation improvement strategies, including glycosyltransferase over expression and nucleotide sugar feeding. These multiprong approaches can possibly bring us closer toward the goal of maximum and consistent sialylation in glycoprotein production using mammalian cells. © 2006 Wiley Periodicals, Inc.
Retrieval of abdominal organs for transplantation
Authors: Brockmann J G , Vaidya A , Reddy S , Friend P J
Published: January 2006

Background

Organ retrieval and donor management are not yet standardized. Different transplant centres apply various techniques, such as single or dual organ perfusion, dissection in the cold or warm, and single or en bloc organ removal. These different approaches may cause inconvenience, especially when more than one organ retrieval team is involved.

Methods

Cochrane Library, Medline and PubMed were searched for publications on multiorgan donor/donation, retrieval technique and procurement. Levels of evidence and grades of recommendation were evaluated based on current advice from the Oxford Centre for Evidence-Based Medicine.

Results

Multiorgan donation itself does not compromise the outcome of individual organ transplants. Dissection of abdominal organs for transplantation is best performed after cold perfusion. Abdominal organs should be removed rapidly, en bloc, and separated during back-table dissection in the cold, particularly if pancreas or intestine is included. Perfusion itself should be carried out after single cannulation of the aorta with an increased pressure.

Conclusion

Although the literature on organ retrieval is extensive, the level of evidence provided is mainly low. Nevertheless, optimized donor treatment and organ retrieval should increase the number and quality of cavaderic donor organs and improve graft function and survival.
Caution with sentinel node biopsy in cutaneous melanoma
Authors: Thomas J M
Published: January 2006

No justification outside of a trial
Randomized clinical trial comparing multiple stab incision phlebectomy and transilluminated powered phlebectomy for varicose veins
Authors: Chetter I C , Mylankal K J , Hughes H , Fitridge R
Published: January 2006

Background

The aim was to compare early postoperative subjective outcome measures in a randomized trial of multiple stab incision phlebectomy (MSIP) and transilluminated powered phlebectomy (TIPP) for the treatment of varicose veins.

Methods

Patients having surgery for varicose veins were randomized to receive either MSIP or TIPP for local avulsion of varicose veins. Operating time, number of incisions and postoperative outcome were analysed in both groups. Quality of life (QoL) was analysed before and 1 and 6 weeks after surgery using domain-specific (Burford pain scale), disease-specific (Aberdeen Varicose Vein Questionnaire) and generic (Short Form 36 and EuroQol 5D) instruments.

Results

Sixty-six patients consented to participate in the trial but four withdrew before surgery, so 33 patients underwent MSIP and 29 patients had TIPP. All patients had symptomatic or complicated varicose veins. There was no significant difference between groups in the total duration of surgery or the time taken for the avulsions. The number of incisions was significantly lower with TIPP. However, skin bruising at 1 and 6 weeks, and Burford pain score at 6 weeks were significantly higher in the TIPP group (P < 0·01 for bruising and P = 0·019 for pain). TIPP also had a greater adverse impact on generic QoL, resulting in a more prolonged recovery.

Conclusion

TIPP had the advantage of fewer surgical incisions, but was associated with more extensive bruising, prolonged pain and reduced early postoperative QoL.
Mesoporous Hybrid Thin Films: The Physics and Chemistry Beneath
Authors: Soler‐Illia G. J. A. A. , Innocenzi P.
Published: January 2006

Mesoporous films containing organic or biological functions within an organised array of cavities are produced by combining sol–gel, self‐assembly of supramolecular templates and surface chemistry. This paper reviews the essential physics and chemical concepts behind the synthesis of these complex multifunctional materials.
Effects of Dipolar Interactions on Linear and Nonlinear Optical Properties of Multichromophore Assemblies: A Case Study
Authors: Terenziani Francesca , Mongin Olivier , Katan Claudine , Bhatthula Bharath Kumar Goud , Blanchard‐Desce Mireille
Published: January 2006

Interchromophore interactions in flexible multidipolar structures for nonlinear optics were addressed by a combined experimental and theoretical study on two series of one‐, two‐, and three‐chromophore systems in which identical push–pull chromophores are assembled through covalent and flexible linkers in close proximity. The photophysical and nonlinear optical properties (quadratic hyperpolarizability) of the multichromophore systems were investigated and compared to those of the monomeric chromophores. Multimers have larger dipole moments than their monomeric analogues, that is, the dipolar subchromophores self‐orientate within the multimeric structures. This effect was found to depend on the intersubchromophore distance in a nontrivial manner, which confirms that molecular engineering of such flexible systems is more complex than in completely geometrically controlled systems. Electric‐field‐induced second‐harmonic generation (EFISHG) measurements in solution revealed increased figures of merit as compared to the monomeric analogue. This effect increases with increasing number and polarity of the individual subchromophores in the nanoassembly and increasing spacing between dipolar subchromophores. Experimental results are interpreted by a theoretical model for interacting polar and polarizable chromophores. The properties of multidipolar assemblies are shown to be related to the relative orientation of chromophores, which is imposed by interchromophore interactions. The supramolecular structure is thus a result of self‐organization. The proposed theoretical model was also used to predict the properties of multichromophore structures made up of more polar and polarizable push–pull chromophores, and showed that stronger interchromophore interactions can heavily affect the individual optical responses. This suggests new routes for engineering highly NLO responsive multichromophore systems.
Systematic Investigation of the Formation of 1D α‐Si3N4 Nanostructures by Using a Thermal‐Decomposition/Nitridation Process
Authors: Shen Guozhen , Bando Yoshio , Liu Baodan , Tang Chengchun , Huang Qing , Golberg Dmitri
Published: January 2006

This article describes a simple thermal‐decomposition/nitridation method for the large‐scale synthesis of 1D α‐Si3N4 nanostructures, such as millimeter‐scale microribbons, nanosaws, nanoribbons, and nanowires. These nanostructures are systematically investigated by checking the product deposited at different areas by using powder X‐ray diffraction, scanning electron microscopy, transmission electron microscopy, and electron energy loss spectroscopy. Studies show that all these nanostructures have a single‐crystalline nature and predominately grow along the [011] direction. These 1D nanostructures are formed by thermal decomposition, followed by the nitridation of SiO.
Density Functional Studies on the Nazarov Reaction Involving Cyclic Systems
Authors: Cavalli Andrea , Masetti Matteo , Recanatini Maurizio , Prandi Cristina , Guarna Antonio , Occhiato Ernesto G.
Published: January 2006

Density functional theory (DFT) has been used to define the energy profiles of the Nazarov reaction involving cyclic systems. The calculations were carried out at the B3LYP/6‐311G** level of theory and the solvent (dichloromethane) contribution was estimated by using the recently developed SM5.43R solvation model. DFT calculations were first carried out to determine the energy profiles associated with the electrocyclization reactions of 3‐hydroxy‐ and 3‐ethoxypentadienyl cations in which one of the double bonds is embedded in O‐heterocyclic and carbocyclic systems. In particular, the effects on the reaction rate of modifications to the substrate, as well as the presence of the heteroatom in the cycle, have been investigated. The torquoselectivity of the electrocyclization reaction was then explored with substituted O‐heterocycles to understand the factors that control the stereochemical outcome of the process that preferentially provides 2,5‐trans‐disubstituted products. These DFT‐based results rationally explain most of the experimental observations related to the Nazarov reaction of the substrates herein investigated and could be useful in the rational interpretation, and likely in the prediction, of the outcome of Nazarov reactions involving other cyclic systems.
Stable Expression of Soluble Therapeutic Peptides in Eukaryotic Cells by Multimerisation: Application to the HIV‐1 Fusion Inhibitory Peptide C46
Authors: Dervillez Xavier , Hüther Alexandra , Schuhmacher Jochen , Griesinger Christian , Cohen Jacques H. , von Laer Dorothee , Dietrich Ursula
Published: January 2006

A major drawback of therapeutic peptides is their short half‐life, which results in the need for multiple applications and high synthesis costs. To overcome this, we established a eukaryotic expression system that allows the stable expression of small therapeutic peptides by multimerisation. By inserting the sequence encoding the therapeutic peptide between a signal peptide and the multimerising domain of the α‐chain from the human C4bp plasma protein, therapeutic peptides as small as 5 kDa are secreted as multimers from transfected cells; this allows easy purification. As proof of principle, we show that the T20‐derived HIV‐1 fusion inhibitory peptide C46 in its multimeric form: i) was efficiently secreted, ii) was more stable than the current antiviral drug T20 in vitro and in vivo, and iii) inihibited HIV‐1 entry with similar efficiency in vitro. Besides the gain in stability, multimerisation also leads to increased valency and allows the combination of several therapeutic functions. Furthermore, by expressing the multimers from cells, post‐translational modifications could easily be introduced.
Hypersusceptibility to cisplatin carcinogenicity in metallothionein‐I/II double knockout mice: Production of hepatocellular carcinoma at clinically relevant doses
Authors: Waalkes Michael P. , Liu Jie , Kasprzak Kazimierz S. , Diwan Bhalchandra A.
Published: January 2006

Metallothionein (MT) is a high‐affinity metal binding protein thought to mitigate the toxicity of various metals. Cisplatin is a widely used cancer chemotherapeutic that is a rodent carcinogen and may have carcinogenic potential in humans. MT seems to reduce cisplatin toxicity by binding the metal compound but how MT deficiency might impact the carcinogenic effects of cisplatin is unknown. Thus, groups (n = 25) of male MT‐I/II double knockout (MT‐null) or MT wild‐type (WT) mice were exposed to a single treatment of cisplatin (5 or 10 mg/kg, i.p.), or left untreated (control) and observed over the next 104 weeks. The doses of cisplatin used equate to only a fraction of the total dose used typically in clinical settings. In cisplatin‐treated MT‐null mice, a dose‐related increase in hepatocellular carcinoma (HCC) occurred (control, 0%; 5 mg/kg, 17%; 10 mg/kg, 36%) that was not seen in WT mice. Similarly, liver carcinoma multiplicity (HCC/liver) was increased markedly by cisplatin but only in MT‐null mice, indicating the formation of multiple primaries in MT deficient mice. Harderian gland carcinoma incidence was also increased by cisplatin treatment in MT‐null mice but not WT mice. Our results indicate that MT‐null mice are hypersusceptible to the hepatocarcinogenic effects of cisplatin, and poor MT expression may be a predisposing factor for cisplatin‐induced secondary tumors after chemotherapy. © 2006 Wiley‐Liss, Inc.
Cancer risk among chernobyl cleanup workers in Estonia and Latvia, 1986–1998
Authors: Rahu Mati , Rahu Kaja , Auvinen Anssi , Tekkel Mare , Stengrevics Aivars , Hakulinen Timo , Boice John D. , Inskip Peter D.
Published: January 2006

Two cohorts of Chernobyl cleanup workers from Estonia (4,786 men) and Latvia (5,546 men) were followed from 1986 to 1998 to investigate cancer incidence among persons exposed to ionizing radiation from the Chernobyl accident. Each cohort was identified from various independent sources and followed using nationwide population and mortality registries. Cancers were ascertained by linkage with nationwide cancer registries. Overall, 75 incident cancers were identified in the Estonian cohort and 80 in the Latvian cohort. The combined‐cohort standardized incidence ratio (SIR) for all cancers was 1.15 (95% confidence interval (CI) = 0.98–1.34) and for leukemia, 1.53 (95% CI = 0.62–3.17; n = 7). Statistically significant excess cases of thyroid (SIR = 7.06, 95% CI = 2.84–14.55; n = 7) and brain cancer (SIR = 2.14, 95% CI = 1.07–3.83; n = 11) were found, mainly based on Latvian data. However, there was no evidence of a dose response for any of these sites, and the relationship to radiation exposure remains to be established. Excess of thyroid cancer cases observed may have been due to screening, the leukemia cases included 2 unconfirmed diagnoses, and the excess cases of brain tumors may have been a chance finding. There was an indication of increased risk associated with early entry to the Chernobyl area and late follow‐up, though not statistically significant. Further follow‐up of Chernobyl cleanup workers is warranted to clarify the possible health effects of radiation exposure. © 2006 Wiley‐Liss, Inc.
Serological immune response to cancer testis antigens in patients with pancreatic cancer
Authors: Wadle Andreas , Kubuschok Boris , Imig Jochen , Wuellner Beate , Wittig Christine , Zwick Carsten , Mischo Axel , Waetzig Kristin , Romeike Bernd F.M. , Lindemann Werner , Schilling Martin , Pfreundschuh Michael , Renner Christoph
Published: January 2006

Serological screening approaches have allowed for the identification of a large number of potentially relevant tumor antigens in cancer patients. Within this group, cancer testis antigens represent promising targets for cancer immunotherapy, since they are widely expressed in a variety of human cancer entities. In pancreatic cancer, however, there are only few data available about the expression pattern and serological response to cancer testis antigens and other serological‐defined tumor antigens. Therefore, we investigated the IgG antibody response against 11 cancer testis antigens (SCP‐1, GAGE, LAGE‐1a,‐1b, CT‐7, NY‐ESO‐1, SSX‐1‐5) recombinantly expressed on yeast surface (RAYS) in patients with pancreatic cancer (n = 96), chronic pancreatitis (n = 18) and healthy donors (n = 48). We found in 14% of all patients antibody responses to SCP‐1, but not to other cancer testis antigens (GAGE, LAGE‐1a,‐1b, CT‐7, NY‐ESO‐1, SSX‐1‐5). Antibody response correlated with the expression of SCP‐1 in the primary tumor of the respective patient as shown by RT‐PCR, immunohistochemistry and Western blot. In contrast, no serological response to cancer testis antigens was observed in healthy donors. The humoral immune response against SCP‐1 was associated with the size of tumor, but not with other clinico‐pathological parameters such as histology, stage, presence of lymph node metastases, grading, age, gender or gemcitabine treatment. In conclusion, antibody response to cancer testis antigen SCP‐1 is found in a proportion of pancreatic carcinoma patients. These results indicate that identification of additional tumor antigens by serological screening of tumor cDNA expression libraries by RAYS is a promising goal in pancreatic cancer. © 2006 Wiley‐Liss, Inc.
9‐O‐acetyl GD3 protects tumor cells from apoptosis
Authors: Kniep Bernhard , Kniep Eva , Özkucur Nurdan , Barz Steffen , Bachmann Michael , Malisan Florence , Testi Roberto , Rieber Ernst Peter
Published: January 2006

The ganglioside GD3 (Neu5Acα8Neu5Acα3Galβ4GlcCer) is an intracellular lipid messenger that induces apoptosis by targeting mitochondria in various cell types. GD3 can also promote apoptosis when externally added to cells. Previous studies showed that the proapoptotic effects of GD3 can be counteracted by 9‐O‐acetylation. To determine whether 9‐O‐acetyl GD3 (acGD3) has a general antiapoptotic potential, the apoptosis‐sensitive Jurkat cell line and an apoptosis‐sensitive variant of the cell line Molt‐4 were preincubated with micromolar concentrations of acGD3 and then treated with inducers of apoptosis. A reduced apoptotic index and an increased cell viability were observed. On the other hand, when the Jurkat cells were treated with GD3 for extended periods of time, a population was selected that was resistant to apoptosis induction by N‐acetyl sphingosine as well as by the anti‐leukemic drug daunorubicin. Comparative analysis of gangliosides revealed the formation of acGD3 in the resistant Jurkat cells that was not found in the apoptosis‐sensitive cells. Conversely, exposing the acGD3 positive and apoptosis‐resistant cell line Molt‐4 to the O‐deacetylating activity of salicylate resulted in a complete disappearance of acGD3 and an enhanced sensitivity to N‐acetyl sphingosine‐mediated apoptosis. Formation of acGD3 might thus represent a new mechanism how tumor cells can escape apoptosis. © 2006 Wiley‐Liss, Inc.
Prophylaxis of oxidative DNA damage by formamidopyrimidine‐DNA glycosylase
Authors: Frosina Guido
Published: January 2006

Lying at the gas‐exchange interface, lung epithelia may be at risk of oxidation‐induced mutagenesis. Further, inflammation processes possibly consequent on smoking liberate reactive oxygen species that multiply the carcinogenic effects of tobacco. DNA repair mechanisms play a major role in counteracting the deleterious effects of oxidative DNA damage. Some studies find positive associations between lung cancer and variations in the human 8‐oxoguanine DNA glycosylase (hOGG1) gene that encodes a major DNA glycosylase for oxidized lesions with sluggish kinetics properties. The bacterial homologue formamidopyrimidine‐DNA glycosylase (FPG) is 80‐fold faster than hOGG1 in repairing mutagenic oxidative lesions. Cell‐culture studies have shown that FPG can be expressed in mammalian cells, where it accelerates DNA repair and abates mutagenicity of a wide range of DNA‐damaging agents. Prophylaxis of oxidative DNA damage and mutation could be achieved in lung epithelia and other tissues of at‐risk individuals by expression of the FPG protein. Currently available vehicles for this peculiar type of gene therapy are briefly surveyed. © 2006 Wiley‐Liss, Inc.
Structural characterization of flavonol 3,7‐di‐O‐glycosides and determination of the glycosylation position by using negative ion electrospray ionization tandem mass spectrometry
Authors: Ablajan Keyume , Abliz Zeper , Shang Xiao‐Ya , He Jiu‐Ming , Zhang Rui‐Ping , Shi Jian‐Gong
Published: January 2006

Flavonol 3,7‐di‐O‐glycosides were investigated by negative ion electrospray ionization tandem mass spectrometry using a quadrupole linear ion trap (LIT) mass spectrometer. The results indicate that the fragmentation behavior of flavonol 3,7‐di‐O‐glycosides is substantially different from that of their isomeric mono‐O‐diglycosides. In order to characterize a flavonoid as a flavonol 3,7‐di‐O‐glycoside, both [Y30− H]−•and [Y0− 2H]−ions should be present in [M − H]−product ion spectrum. The MS3product ion spectra of Y30−, [Y30− H]−•and Y70−ions generated from the [M − H]−ion provide sufficient structural information for the determination of glycosylation position. Furthermore, the glycosylation positions are determined by comparing the relative abundances of Y30−and Y70−ions and their specific fragmentation patterns with those of flavonol mono‐O‐glycosides. In addition, a [Y30− H]−•ion formed by the homolytic cleavage of 3‐Oglycosidic bond with high abundance points to 3‐Oglycosylation, while a [Y0− 2H]−ion formed by the elimination of the two sugar residues is consistent with glycosylation at both the 3‐Oand 7‐Opositions. Investigation of negative ion ESI‐MS2and MS3spectra of flavonolO‐glycosides allows their rapid characterization as flavonol 3,7‐di‐O‐glycoside and their differentiation from isomeric mono‐O‐diglycosides, and also enables their direct analysis in crude plant extracts. Copyright © 2006 John Wiley & Sons, Ltd.
Effects of anthocyanins and other phenolics of boysenberry and blackcurrant as inhibitors of oxidative stress and damage to cellular DNA in SH‐SY5Y and HL‐60 cells
Authors: Ghosh Dilip , McGhie Tony K , Zhang Jingli , Adaim Aselle , Skinner Margot
Published: January 2006

There is growing interest both from consumers and researchers in the role that berries play in human health. The objective of this study was to investigate whether anthocyanins and other phenolics present in boysenberries and blackcurrants are effective in protecting cells against the oxidative damage induced by hydrogen peroxide (H2O2). The concentrations of polyphenols used were within the human physiological range. The data showed that SH‐SY5Y human neuroblastoma cells were protected against H2O2‐induced toxicity by the anthocyanins and phenolic fractions. The concurrent addition of either fractions of these berries with H2O2significantly inhibited the increase in intracellular reactive oxygen species (ROS) production. Pre‐incubation of cells with the same concentrations had no effect on the ROS level—a result that may be due to the metabolic conversion to inactive compounds. Anthocyanins and phenolic fractions of blackcurrant were better at protecting DNA of HL‐60 human promyelocytic cells from damage than similar fractions from boysenberry. The phenolic extract of blackcurrant demonstrated the highest protective effect against H2O2‐induced neurotoxicity, oxidative stress and DNA damage and may be a good candidate for inclusion into a processed functional food. Copyright © 2006 Society of Chemical Industry
Study on the Graft Reaction of Poly(propylene) Fiber with Acrylic Acid
Authors: Wang Wei , Wang Li , Chen Xu , Yang Qiang , Sun Tianxu , Zhou Junfeng
Published: January 2006

Summary: In this paper, the graft of poly(propylene) fiber with acrylic acid is investigated. The effects of grafting temperature, monomer concentration, and grafting time on the grafting degree of acrylic acid onto poly(propylene) fiber are discussed. In contrast to the conventional method of determining the grafting degree gravimetrically, the acid‐base titration method used in this paper was more efficient, even at low grafting degree. High‐performance liquid chromatography (HPLC) was used to estimate the averaged length of the grafted poly(acrylic acid) chains on each grafted site of poly(propylene) backbone. And also a mechanism for the grafting polymerization is proposed.

Possible microstructures of two PP‐g‐AA samples at the same grafting degree.

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Possible microstructures of two PP‐g‐AA samples at the same grafting degree.
Propylene/1‐Hexene Copolymer as a Tailor‐Made Poly(propylene) for Membrane Preparation via the Thermally Induced Phase Separation (TIPS) Process
Authors: Yave Wilfredo , Quijada Raúl , Lloyd Douglas R. , Cerrada María L. , Benavente Rosario , Ulbricht Mathias
Published: January 2006

Summary: Poly[propylene‐co‐(1‐hexene)], one example of a “tailor‐made poly(propylene)”, was synthesized using an iso‐specific metallocene catalyst in order to study the influence of copolymer composition on the pore size of isotactic poly(propylene) (iPP) membranes prepared by the TIPS process. The structure of the copolymers and their properties in solution were analyzed and discussed in relation to the polymer‐diluent phase diagram, the droplet growth kinetics during the TIPS process, the viscosity of the system and the final pore size of the membranes. The crystallization curve in the phase diagram was found to shift significantly as comonomer content increased and thus the droplet growth period was drastically increased. The resulting increase of the characteristic pore size in the membranes demonstrated that it is possible to use tailor‐made poly(propylene)s to control the pore size in porous membranes prepared via the TIPS process (under otherwise constant conditions).

Porous size is controlled by the polymer and the TIPS process.

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Porous size is controlled by the polymer and the TIPS process.
Effects of Temperature on Morphology and Properties of Films Prepared from Poly(ester‐urethane) and Nitrochitosan
Authors: Zeng Ming , Zhang Lina
Published: January 2006

Summary: Novel elastic materials were prepared by mixing semicrystalline polyester‐based polyurethane (PU) synthesized at 100 °C with nitrochitosan (NCH) and 1,1,1‐tris(hydroxylmethyl)propane as crosslinker, and then by curing the mixture at 18, 25, 40, 60, and 80 °C. The effects of cure temperature on the crystallization behavior, miscibility, and mechanical properties of the PUNCH materials were studied by attenuated total reflection Fourier transform IR, wide‐angle X‐ray diffraction, scanning electron microscopy, dynamic mechanical analysis, X‐ray photoelectron spectroscopy, and tensile test. The results indicated that the crystalline structure of the blend films was more easily interrupted as the cure temperature increased, leading to a decrease of the degree of crystallinity. With an increase of cure temperature, the blend films exhibited high crosslinking density and tensile strength, and the phase separation between hard and soft segments of PU enhanced, resulting in a decrease in the glass transition temperature (Tg) of soft segment. Interestingly, the composite films keeping high elongation at break possessed tensile strength higher than that of the native poly(ester‐urethane). The enhanced mechanical properties of the blend films can be attributed to the relatively dense crosslinking network and strong intermolecular hydrogen bonding between NCH and PU. Therefore, this study not only provided a novel way by adding NCH into PU matrix to prepare elastic materials, which would remain functional characteristic of chitosan, but also expanded the application field of chitosan.

The cure temperature dependence of the tensile strength and elongation at break for the PEPU‐100 and PUNCH‐100 films.

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The cure temperature dependence of the tensile strength and elongation at break for the PEPU‐100 and PUNCH‐100 films.
Click Chemistry with Polysaccharides
Authors: Liebert Tim , Hänsch Claudia , Heinze Thomas
Published: January 2006

Summary: The copper‐catalyzed Huisgen reaction as a typical example of click chemistry was realized with the polysaccharide cellulose for the first time. The generality, selectivity, and the efficiency of click chemistry perfectly fit the requirements of polysaccharide modification, which is demonstrated by the introduction of triazole‐spacer bound functional groups, i.e., carboxylic ester, thiophene, and aniline moieties. Azide moieties introduced into cellulose via the tosyl derivative were simply transferred with ethynyl compounds under Cu(I) catalysis and mild and easily applicable conditions. Hydrolytically stable cellulose derivatives soluble in organic solvents, e.g., DMSO or DMF with DS up to 0.9 are obtained. The triazole substituted cellulose derivatives were characterized by elemental analysis, FTIR, 1H NMR, and 13C NMR spectroscopies and show no impurities or substructures resulting from side reactions.

6‐Azido‐6‐deoxy cellulose.

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6‐Azido‐6‐deoxy cellulose.
Ionic Polymer‐Metal Composite Actuators Employing Radiation‐Grafted Fluoropolymers as Ion‐Exchange Membranes
Authors: Han Man Jae , Park Jong Hyuk , Lee Jang Yeol , Jho Jae Young
Published: January 2006

Summary:To develop ionic polymer‐metal composites (IPMC) with improved performance, three new ion‐exchange membranes were prepared and employed in IPMC construction. The membranes were prepared by radiation‐grafting of polystyrene sulfonic acid onto three fluoropolymers; poly(vinylidenefluoride‐co‐hexafluoropropylene), poly(ethylene‐co‐tetrafluoroethylene), and poly(tetrafluoroethylene‐co‐hexafluoropropylene). The bending displacements of the IPMCs constructed with these membranes were at least several times larger than that of Nafion IPMC of similar thickness without straightening‐back. The larger displacement was considered to be due to the higher concentration of ionic groups and consequent larger ion‐exchange capacity.

Actuation of (a) Nafion IPMC and (b) IPMC prepared in this study.

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Actuation of (a) Nafion IPMC and (b) IPMC prepared in this study.
New Strategy for Enzymatic Synthesis of High‐Molecular‐Weight Poly(butylene succinate) via Cyclic Oligomers
Authors: Sugihara Satoko , Toshima Kazunobu , Matsumura Shuichi
Published: January 2006

Summary: High‐molecular‐weight poly(butylene succinate) (PBS) is prepared by the lipase‐catalyzed polymerization of dimethyl succinate and butane‐1,4‐diol via the formation of cyclic oligomers as a new strategy for the green production of bio‐based plastics. The cyclic oligomer is first produced by the lipase‐catalyzed condensation of dimethyl succinate and butane‐1,4‐diol in a dilute toluene solution using lipase from Candida antarctica, followed by the ring‐opening polymerization of the cyclic oligomer in a more concentrated solution or in bulk with the same lipase to produce PBS with an of 130 000. On the other hand, PBS is produced with an of 45 000 by direct polycondensation.

The lipase‐catalyzed preparation of PBS by two routes.

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The lipase‐catalyzed preparation of PBS by two routes.