bluuebunny/crossref_metadata_2025 huggingface dataset:
An integrative model of managerial perceptions of employee commitment: antecedents and influences on employee treatment
Authors: Shore Ted H. , Bommer William H. , Shore Lynn M.
Published: February 2008

An integrative model of antecedents and outcomes of managerial perceptions of employee organizational commitment was developed and tested with 490 employees of a publicly owned U.S. manufacturing firm. The results are consistent with predictions showing that self‐reported affective commitment and supervisor‐focused impression management predicted managerial perceptions of affective commitment, whereas age, tenure, education, training and development, and self‐focused impression management were related to managerial perceptions of continuance commitment. Furthermore, manager‐rated affective and continuance commitment were differentially related to supervisory treatment of the employee (i.e. receiving contingent rewards and non‐contingent punishment). The results of this study show how managers develop perceptions of affective and continuance commitment, and through their associated treatment of employees, has important implications for the ways managers may serve to enhance or detract from employee contributions to the organization. Copyright © 2008 John Wiley & Sons, Ltd.
Resolving the database sequence discrepancies for the Staphylococcus aureus bacteriophage ϕ 11 amidase
Authors: Donovan David M. , Foster‐Frey Juli , Garrett Wesley M. , Blomberg LeAnn
Published: February 2008

There are two conflicting primary nucleotide sequences of the Staphylococcus aureus bacteriophage ϕ 11 amidase gene in Genbank. Nucleotide sequence differences as well as alternative translational start site assignments result in three non‐identical protein sequence predictions for this amidase. Therefore, it is prudent to verify the correct phi11 amidase protein sequence, especially since multiple versions of the amidase gene have been subcloned, deletion analysis performed, and their experimental use described. There is also a resurgence of interest in the expression and use of bacteriophage lytic proteins as bactericidal agents and the ϕ 11 amidase has a high antimicrobial potential. The correct amidase sequence is identified through a combination of DNA sequence analysis and matrix‐assisted laser desorption/ionization‐time‐of‐flight mass spectrometry analysis of the recombinant purified phi11 amidase protein. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Phenotypic and genotypic heterogeneity of Enterococcus species isolated from food in Southern Brazil
Authors: Pelicioli Riboldi Gustavo , Preusser de Mattos Eduardo , Guedes Frazzon Ana Paula , Alves d'Azevedo Pedro , Frazzon Jeverson
Published: February 2008

Enterococcus is an important group of lactic acid bacteria (LAB), which inhabits the gastrointestinal tract of humans and animals. These microorganisms can also be found in large groups of foods where they can play a beneficial role during food maturation processes or, conversely, can be used as a food contamination indicator. These microorganisms have an additional importance in various aspects of clinical microbiology. The aim of this study was to investigate and determine the phenotypic and genetic diversity in 55 enterococci isolated from different food sources. Phenotypic characteristics based upon substrate hydrolysis differences were used to identify different Enterococcus species. Analysis of the resultant data divided these species into eight Enterococcus phenotype groups. E. faecalis was the food isolate species with the greatest phenotypic variability. Fifty‐five previously isolated Enterococcus strains were re‐confirmed as belonging to this genus by PCR techniques. Randomly amplified polymorphic DNA (RAPD‐PCR) was used to study the genetic variability using M13 primers and the resultant DNA fragments produced a database of different fingerprints. After statistical analyses of the RAPD‐PCR profiles, 42 patterns were obtained and 6 different Enterococcus RAPD clusters (ERC) were identified. Genetic diversity was highest in ERC I, which grouped together approximately 40% of the E. faecium and E. faecalis isolates obtained from dairy products. Samples isolated from meat and vegetables offered the greatest genotype variability. Results of the present study suggest the presence of both phenotypic and genotypic variability within enterococci strains isolated from diverse sources of food common to Southern Brazil. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Characterization of the E. coli glucose permease fused to the maltose‐binding protein
Authors: Aboulwafa Mohammad , Saier Milton H.
Published: February 2008

The ptsG gene that encodes the major glucose transporter of Escherichia coli, IIGlc, was inserted into a pMALE‐ampr expression vector down‐stream of the malE gene which encodes the E. coli maltose‐binding protein (MBP). IIGlc‐MBP in the 2 h high speed supernatant of cell lysates eluted from a gel filtration column showing two activity peaks. The glucose‐6‐phosphate‐dependent transphosphorylation (TP) activity of the membrane bound oligomeric peak 1 showed substrate inhibition while that of the soluble monomeric peak 2 did not. Purification of peak 2 yielded activity with weak substrate inhibition, and further gel filtration analyses showed that upon purification, some of the monomeric IIGlc‐MBP associated to higher molecular size forms. Assays of the phosphoenolpyruvate‐dependent and transphosphorylation reactions showed that the specific activity of the purified enzyme from peak 1 was approximately double that from peak 2. The results show that the monomeric IIGlc‐MBP exhibits no substrate inhibition although the oligomeric form does. Purification promotes subunit association, an increase in catalytic activity, and restoration of substrate inhibition. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Analyses structurales et spectrales du 5,6‐diméthyluracile
Authors: Selkti M. , Vachoud L. , Bourret E. , Kister G. , Tomas A. , Maury L. , Delarbre J. L.
Published: February 2008

The molecular structure of 5,6‐dimethyluracil monohydrate C6H8N2O2H2O has been determined by X‐ray diffraction method. The crystals are monoclinic space group P21/n with a = 6.667 (2), b = 6.784 (4), c = 16.759 (2) Å, β = 99.08 (2)° , V = 748.6 (5) Å3 and z = 4. The structure was refined to R = 0.064. The Raman and infrared spectra of the crystalline powders of the 5,6‐dimethyluracil monohydrate, anhydrous and deuterated forms were investigated from 4000–200 cm−1. An assignment of the normal modes is proposed.

RÉSUMÉ

La structure moléculaire du 5,6‐diméthyluracile monohydrate C6H8N2O2H2O a été déterminée par diffraction des rayons X. Les cristaux appartiennent au groupe d'espace monoclinique P21/n avec a = 6,667 (2), b = 6,784 (4), c = 16,759 (2) Å, β = 99, 08 (2), V = 748,6 (5) Å3 et z = 4. La structure a été affinée jusqu'à un facteur R = 0,064. Les spectres Raman et infrarouge des poudres cristallines du 5,6‐diméthyluracile monohydrate, anhydre et deutérié ont été analysés de 4000 à 200 cm−1. Une attribution de l'ensemble des vibrations fondamentales a été proposée. Copyright © 2008 John Wiley & Sons, Ltd.
Application of surface‐enhanced Raman spectroscopy (SERS) to the analysis of natural resins in artworks
Authors: Lau Deborah , Livett Michelle , Prawer Steven
Published: February 2008

Surface‐enhanced Raman spectroscopy (SERS) is rapidly growing as an analytical technique for the detection of extremely low concentrations of analytes. The analysis of natural resins from artworks is often restricted by sample size constraints in general, and Raman spectroscopy in particular is hampered by fluorescence when using visible irradiation wavelengths. This work demonstrates that SERS is able to overcome interference from fluorescence in such samples using the incident wavelength 514.5 nm, to allow collection of SERS spectra from extremely small samples. Characterisation of the natural resin surface coating from a painting by Tiepolo is discussed. Copyright © 2008 John Wiley & Sons, Ltd.
High concentration trans form unsaturated lipids detected in a HeLa cell by Raman microspectroscopy
Authors: Onogi Chikao , Motoyama Michiyo , Hamaguchi Hiro‐o
Published: February 2008

High concentration trans form unsaturated lipids have been found in a HeLa cell by Raman microspectroscopy. Two CC stretch bands are observed simultaneously at 1669 cm−1 (trans form) and at 1656 cm−1 (cis form) in a Raman spectrum obtained from a small area (1 µm in diameter) in a HeLa cell. The intensity ratio 1669/1656 indicates that the concentration of the trans form is as high as that of the cis. It is demonstrated that Raman microspectroscopy provides a powerful and unique means for in situ and noninvasive structural characterization of unsaturated lipids in a living cell. Copyright © 2008 John Wiley & Sons, Ltd.
Effect of vacuum frying on main physicochemical and nutritional quality parameters of pineapple chips
Authors: Perez‐Tinoco Maria Rosalba , Perez Ana , Salgado‐Cervantes Marco , Reynes Max , Vaillant Fabrice
Published: February 2008

BACKGROUND: Slices of MD‐2 pineapple hybrid were vacuum fried at 24 kPa according to a central composite experimental design that simultaneously varied frying time (6.3–7.7 min) and temperature (106.3–117.7 °C). Major physicochemical and nutritional quality factors were measured and modelled using a second‐order polynomial equation.

RESULTS: Moisture content, water activity aw, colour parameters L*, C* and H* and total vitamin C content decreased while total phenolic content and dehydroascorbic acid content increased with increasing frying time and temperature. Oil content, hardness and hydrophilic antioxidant capacity reached minimum values near the centre of the experimental field. By superimposing contour curves, it was determined that processing conditions of 6.9 min frying time and 112 °C frying temperature produced pineapple chips with a golden colour (L*≥ 60, C*≥ 50, H*≥ 80), an aw of less than 0.29, a moisture content of about 4% and a hardness of less than 1.9 N, giving rise to a crispy texture. Oil content was about 20% (d.b) and residual total vitamin C content (∼90 mg per 100 g wet basis (w.b.)) was high. Phenolic compound content was about 150 mg gallic acid equivalents per 100 g w.b. and antioxidant capacity was around 22 µmol Trolox equivalents g−1 w.b.

CONCLUSION: Vacuum frying is a dehydration process that produces healthy fruit snacks which partially preserve the fruit's original colour and nutritional compounds and have a high hydrophilic antioxidant capacity. Copyright © 2008 Society of Chemical Industry
Radical‐scavenging properties of extracts from the white button mushroom, Agaricus bisporus
Authors: Savoie Jean‐Michel , Minvielle Nathalie , Largeteau Michèle L
Published: February 2008

BACKGROUND: Agaricus bisporus is the premier cultivated edible mushroom but is usually considered to be of lesser value nutritionally and medicinally compared with other cultivated mushrooms. The objective of this study was to investigate the radical‐scavenging properties of methanolic extracts and the free radical‐processing enzyme activities of water extracts from A. bisporus fruit bodies. Analyses were performed on total fruit bodies from three strains and on separated stipe, cap and gills from one strain, all cultivated experimentally under the same conditions.

RESULTS: EC50 values of scavenging ability on 1,1‐diphenyl‐2‐picrylhydrazyl radicals (DPPH•), scavenging ability on 2,2‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid) radical cations (ABTS•+) and reducing power of methanolic extracts from total fruit bodies ranged between 1.7 and 5.0 and were 1.1–1.9 times higher in a white hybrid than in two wild strains, cream and brown. The gills exhibited higher antioxidant activities relative to the stipe and cap. In water extracts, glutathione peroxidase activities were up to eight times higher than glutathione reductase activities and no difference was observed between strains. Catalase activity was highest in the brown wild strain. The only significant differences in free radical‐processing enzymes between the three parts of the mushroom were higher catalase activity in the gills and lower glutathione reductase activity in the stipe.

CONCLUSION: The radical‐scavenging properties of the button mushroom are comparable to those of other edible mushrooms and dependent on the strain and on the section of the fruit body. Copyright © 2008 Society of Chemical Industry
Clinical significance of HLA class I heavy chain expression in patients with gastric cancer
Authors: Ueda Yoshitake , Ishikawa Koichi , Shiraishi Norio , Yokoyama Shigeo , Kitano Seigo
Published: February 2008

Background

Little is known about the relation between HLA‐I expression and the prognosis of patients with gastric cancer. The aim of this retrospective study was to clarify the clinical significance of HLA‐I heavy chain expression in gastric cancer.

Methods

The study subjects were 202 patients with gastric cancer who had undergone curative surgery. Tumors were examined for expression of HLA‐I heavy chain antigens by immunohistochemistry. We analyzed the association of HLA‐I heavy chain expression with clinicopathological parameters and patient prognosis.

Results

HLA‐B/C expression showed association with deeper tumor invasion, higher incidence of lymph node metastasis, more advanced tumor stage, and higher incidence of recurrence. Patients with positive HLA‐B/C expression had shorter 5‐year overall and 5‐year disease‐free survival compared with patients whose tumors showed mixed and negative expression (P < 0.05 and 0.01, respectively). In multivariate analysis, although HLA‐B/C expression was not recognized as an independent prognostic factor, it was an independent factor in predicting peritoneal recurrence after curative surgery in patients with gastric cancer [relative risk (RR): 9.924, P = 0.003].

Conclusion

Expression of HLA‐B/C heavy chain is associated with tumor progression, and it could be a significant predictor of peritoneal recurrence after curative surgery in patients with gastric cancer. J. Surg. Oncol. 2008;97:451–455. © 2008 Wiley‐Liss, Inc.
Analysis of carbohydrates and glycoconjugates by matrix‐assisted laser desorption/ionization mass spectrometry: An update covering the period 2001–2002
Authors: Harvey David J.
Published: February 2008

This review is the second update of the original review on the application of MALDI mass spectrometry to the analysis of carbohydrates and glycoconjugates that was published in 1999. It covers fundamental aspects of the technique as applied to carbohydrates, fragmentation of carbohydrates, studies of specific carbohydrate types such as those from plant cell walls and those attached to proteins and lipids, studies of glycosyl‐transferases and glycosidases, and studies where MALDI has been used to monitor products of chemical synthesis. Use of the technique shows a steady annual increase at the expense of older techniques such as FAB. There is an increasing emphasis on its use for examination of biological systems rather than on studies of fundamental aspects and method development and this is reflected by much of the work on applications appearing in tabular form. © 2008 Wiley Periodicals, Inc., Mass Spec Rev 27:125–201, 2008
Tumor suppressor p16INK4A/Cdkn2a alterations in 7, 12‐dimethylbenz(a)anthracene (DMBA)‐induced hamster cheek pouch tumors
Authors: Li Junan , Warner Blake , Casto Bruce C. , Knobloch Thomas J. , Weghorst Christopher M.
Published: February 2008

The prevalence of p16INK4A/Cdkn2a genetic alterations in human oral cancers indicates that the p16 gene could be a potent and appropriate target for novel intervention. While chemically induced hamster cheek pouch (HCP) tumors are regarded as an appropriate surrogate model for human oral cancers because of their similarities to human oral cancers in both histology and genetics, little is known about the genetic events in the p16 gene in the HCP tumor model. The purpose of this study was to evaluate chemically induced HCP tumor specimens for potential inactivating p16 alterations. HCP tumors were induced with 7, 12‐dimethylbenz(a)anthracene (DMBA), and DNA extracted from 34 such specimens were analyzed for homozygous/hemizygous deletions, aberrant methylation of 5′ CpG islands, and point mutations using real‐time multiplex PCR, methylation‐specific PCR, and direct sequencing/cold single strand conformation polymorphism (SSCP), respectively. Homozygous deletions, hemizygous deletions, aberrant methylation of 5′‐CpG islands, and point mutation were identified in 11, 4, 9, and 1 of 34 specimens, respectively. While the overall incidence of p16 alterations was 70.6% (24 of 34 specimens), the majority of inactivating events (67.6%) stemmed from deletion or methylation, which is consistent with the observations found in human oral SCCs. Our results show the resemblance between chemically induced HCP tumors and their human counterparts in p16 genetic alterations, and strongly support the use of DMBA‐induced HCP tumor model in evaluating novel p16‐targeted therapy and prevention of human oral SCCs. © 2008 Wiley‐Liss, Inc.
Modulation of the activities of AMP‐activated protein kinase, protein kinase B, and mammalian target of rapamycin by limiting energy availability with 2‐deoxyglucose
Authors: Jiang Weiqin , Zhu Zongjian , Thompson Henry J.
Published: February 2008

2‐Deoxyglucose (2‐DG), which has been shown to inhibit mammary carcinogenesis, was used as a metabolic probe to investigate effects of limiting energy availability (reduced cellular ATP) on patterns of proteins' phosphorylation that play a role in the development of cancer. Experiments were conducted using a human breast cancer cell line, MDA‐MB‐468, and 1‐methyl‐1‐nitrosourea‐induced rat model for mammary carcinogenesis. Under in vitro conditions in which cellular ATP concentration decreased rapidly with increasing 2‐DG in a dose and time dependent manner, levels of phosphorylated mammalian target of rapamycin (P‐mTOR) decreased in parallel to decreases in ATP concentration. Concomitantly, phosphorylation of two upstream regulators of mTOR, AMP‐activated protein kinase (AMPK) and Akt/protein kinase B were increased and decreased, respectively, with increased levels of phosphorylated acetyl‐CoA carboxylase as an indicator of AMPK activation. Levels of insulin like growth factor 1‐receptor and phosphoinositide‐3 kinase p110α were also reduced. Similar effects were observed in mammary carcinomas in vivo at concentration of 0.03% (w/w) dietary 2‐DG that inhibited carcinogenesis. In vitro, downregulation of mTOR was accompanied by decreases in phosphorylation of two of mTOR's targets, 70‐kDa ribosomal protein S6 kinase and eukaryote initiation factor 4E binding protein 1. Glucose treatment reversed 2‐DG effects. When cells were transfected with dominant‐negative AMPKα2, effects of 2‐DG on mTOR and its downstream effectors were diminished, providing evidence of a link between AMPK and mTOR when energy availability was limited. This work indicates that AMPK, Akt, and mTOR are candidate targets for efforts to inhibit the carcinogenic process by limiting energy availability. © 2008 Wiley‐Liss, Inc.
The sural artery patency test: A useful precaution in risky patients for the reverse sural flap
Authors: Tan Onder
Published: February 2008

The arterial insufficiency is not rare in high risky patients for the reverse sural flap. Thus, we introduce a novel practical technique by performing intraoperative patency test to the sural artery to predetermine the arterial potential, to avoid a possible arterial insufficiency and to increase the reliability of the sural flap in these patients. We succesfully applied the reverse sural flap to seven risky patients with crushing injury, mine explosion, and diabetes, in whom the sural artery patency test was positive. The flap size varied from 8 × 5 cm to 16 × 10 cm. The major defect localization was the heel with/without sole. All flaps survived uneventfully with good contours and durabilities. The sural artery patency test obtain us to decide to safely raise the sural flap or not, and to predict the outcomes of the operative procedure in critical wounds associated with poor arterial supply. © 2008 Wiley‐Liss, Inc. Microsurgery, 2008.
On the solutions of the Moisil–Théodoresco system
Authors: Reyes Juan Bory , Delanghe Richard
Published: February 2008

A structure theorem is proved for the solutions to the Moisil–Théodoresco system in open subsets of ℝ3. Furthermore, it is shown that the Cauchy transform maps L2(ℝ2, ℝ0, 2+) isomorphically onto H2(ℝ+3, ℝ0, 3+), thus proving an elegant generalization to ℝ2 of the classical notion of an analytic signal on the real line. Copyright © 2008 John Wiley & Sons, Ltd.
Methylation status of putative differentially methylated regions of porcine IGF2 and H19
Authors: Han Dong Wook , Im Young Bin , Do Jeong Tae , Gupta Mukesh Kumar , Uhm Sang Jun , Kim Jin‐Hoi , Schöler Hans R. , Lee Hoon Taek
Published: February 2008

This study was designed to identify the putative differentially methylated regions (DMRs) of the porcine imprinted genes insulin‐like growth factor 2 and H19 (IGF2‐H19), and to assess the genomic imprinting status of IGF2‐H19 by identifying the methylation patterns of these regions in germ cells, and in tissues from porcine fetuses, an adult pig, as well as cloned offspring produced by somatic cell nuclear transfer (SCNT). Porcine IGF2‐H19 DMRs exhibit a normal monoallelic methylation pattern (i.e., either the paternally‐ or the maternally derived allele is methylated) similar to the pattern observed for the same genes in the human and mice genomes. Examination of the methylation patterns of the IGF2‐H19 DMRs revealed that the zinc finger protein binding sites CTCF1 and 2 did not exhibit differential methylation in both control and cloned offspring. In contrast, the CTCF3 and DMR2 loci of the IGF2 gene showed abnormal methylation in cloned offspring, but a normal differential or moderate methylation pattern in tissues from control offspring and an adult pig. Our data thus suggest that regulation of genomic imprinting at the porcine IGF2‐H19 loci is conserved among species, and that the abnormal methylation pattern in the regulatory elements of imprinted genes may lead to an alteration in the coordinated expression of genes required for successful reprogramming, which, in consequence, may contribute to the low efficiency of porcine genome reprogramming induced by nuclear transfer. Mol. Reprod. Dev. 75: 777–784, 2008. © 2008 Wiley‐Liss, Inc.
Characterization of heat shock protein 90 in the shrimp Metapenaeus ensis: Evidence for its role in the regulation of vitellogenin synthesis
Authors: Wu Long Tao , Chu Ka Hou
Published: February 2008

Estrogen hormones play a vital role in the regulation of female reproductive maturation. In oviparous vertebrates, the synthesis of vitellogenin (VTG) is tightly controlled by estrogen hormone signal transduction pathway, which is mediated by estrogen receptor and heat shock protein 90 (Hsp90). In order to investigate whether a similar mechanism exists in crustaceans, the Hsp90 gene was cloned and isolated from the shrimp Metapenaeus ensis by homology cloning strategy. The Hsp90 is 2,524 bp in length, containing an open reading frame of 2,163 bp that encodes a 720 amino acid polypeptide (83 kD). The Hsp90‐coding region is interrupted by four introns. MeHsp90 is differentially expressed in eyestalk, ovary, and hepatopancreas at different ovarian maturation stages, and consistently expressed in other tissues including heart, gill, gut, muscle, and central nervous system. In vitro ovary explant assay reveals that MeHsp90 expression in immature ovary can be induced by the addition of exogenous estradiol‐17β, but expression in fully mature ovary exhibits no response to estradiol‐17β treatment. In situ hybridization shows that MeHsp90 is highly expressed in previtellogenic oocytes and its expression decreases with the progress of maturation, and finally stops in late‐vitellogenic oocytes. Our results indicate a strong correlation between estrogen hormones and Hsp90 expression in shrimp, suggesting that the expression of VTG may be under the regulation of estrogen hormones through a mechanism similar to that in vertebrates. The result provides insights on the control of vitellogenesis in invertebrates. Mol. Reprod. Dev. 75: 952–959, 2008. © 2008 Wiley‐Liss, Inc.
The molecular evolution of acrosin in placental mammals
Authors: Raterman Denise , S. Springer Mark
Published: February 2008

Acrosin is thought to fulfill several different roles in fertilization including that of a serine protease and in secondary zona pellucida (ZP) binding. However, acrosin's importance as a fertilization protein has been questioned. Especially since it was discovered that acrosin knockout mice are fertile. In this study, we explored the sites involved in serine protease activity and secondary binding. We also assessed conservation in functional sites across species and examined whether amino acid changes present in the human population have the potential to affect fertility. In addition, since many mammalian reproduction proteins have been found to evolve rapidly, we tested for positive selection. Sequences from 43 mammals from all 19 placental orders, which included a total of 828 nucleotides from acrosin exons 2, 3, 4, and a portion of exon 5, were obtained. We found that all sites of the serine catalytic triad as well as three other sites linked to catalytic activity were completely conserved. Five of six sites proposed to play a role in secondary binding were 100% conserved as basic residues. These results support an evolutionary conserved role for acrosin as a serine protease and secondary binding protein across placental mammals. We found statistically significant support for positive selection within acrosin, but no single amino acid site reached the significance level of P > 0.95 for inclusion within the category ω > 1. Based upon two amino acid mutation scoring systems, three out of seven human residue changing single nucleotide polymorphisms (SNPs) were found to be potentially protein‐altering mutations. Mol. Reprod. Dev. 75: 1196–1207, 2008. © 2008 Wiley‐Liss, Inc.
Ultrastructure of bovine oocytes exposed to Taxol prior to OPS vitrification
Authors: Morató Roser , Mogas Teresa , Maddox‐Hyttel Poul
Published: February 2008

Our objective was to document potential subcellular consequences of treatment with the microtubule stabilizer Taxol with or without subsequent vitrification of cow and calf oocytes by the open pulled straw (OPS) method. Oocytes were divided into four experimental groups for cows and four groups for calves: (1) a control group fixed immediately after maturation; (2) an OPS group cryopreserved by conventional OPS; (3) a Taxol/CPA group exposed to 1 μM Taxol and cryoprotective agents (CPAs); and (4) a Taxol/OPS group vitrified by OPS including 1 μM Taxol to the vitrification solution. All oocytes were processed for light and transmission electron microscopy. The main injuries were observed on the metaphase plate and the spindle. In control oocytes, the metaphase appeared as condensed chromosomes arranged in a well‐organized metaphase plate and the spindle showed well organized microtubules in both cow and calf oocytes. However, in cow OPS oocytes, the metaphase plate was disorganized into scattered chromosomes or the chromosomes were condensed into a single block of chromatin. In addition, microtubules were not organized as typical spindles. In contrast, cow Taxol/OPS oocytes as well as both cow and calf Taxol/CPAs oocytes showed well‐organized metaphase plates and normal spindle morphology. All calf OPS and calf Taxol/OPS oocytes displayed a single block of chromatin and no microtubules could be observed around the chromosomes. In conclusion, treatment with 1 µM Taxol before and during vitrification did not induce adverse changes in the oocyte cytoplasm or metaphase spindles in adult bovine oocytes, but stabilized the metaphase and spindle morphology. Mol. Reprod. Dev. 75: 1318–1326, 2008. © 2008 Wiley‐Liss, Inc.
A heat‐shock protein 40, DNAJB13, is an axoneme‐associated component in mouse spermatozoa
Authors: Guan Jikui , Yuan Li
Published: February 2008

DNAJB13 is a type II HSP40/DnaJ protein. Using a specific antibody raised against the recombinant DNAJB13 protein, we characterized DNAJB13 in mouse testes and epididymal spermatozoa. The expression of DNAJB13 protein in testis was undetectable until postnatal Week 4 revealed by Western blot analysis, whereas Dnajb13 mRNA was detectable as early as postnatal Week 1 by RT‐PCR. Immunohistochemistry analyses showed that DNAJB13 was localized in the cytoplasm of spermatids from step 2 to 3 onward with the strongest expression in step 9–10, and in the spermatid flagella. In mature spermatozoa, DNAJB13 was present along the entire length of the sperm flagellum, but not in the SDS‐resistant tail structures lacking the flagellar axoneme, strongly suggesting that DNAJB13 is an axoneme‐associated component. In addition, we showed that the expression of Dnajb13 mRNA and DNAJB13 protein was unaltered after heat shock treatment, indicating that DNAJB13 was constitutively expressed in mouse testis. Taken together, the present study suggested that DNAJB13 might be involved in assembly and stability of axoneme during sperm flagellum development. Mol. Reprod. Dev. 75: 1379–1386, 2008. © 2008 Wiley‐Liss, Inc.
The methylator phenotype in microsatellite stable colorectal cancers is characterized by a distinct gene expression profile
Authors: Ferracin M , Gafà R , Miotto E , Veronese A , Pultrone C , Sabbioni S , Lanza G , Negrini M
Published: February 2008

The CpG island methylator phenotype (CIMP) in colorectal tumours can be recognized by an increased frequency of aberrant methylation in a specific set of genomic loci. Because of the strong association of CIMP with high microsatellite instability (MSI‐H), the identification of CIMP+ tumours within microsatellite stable (MSS) colorectal cancers may not be straightforward. To overcome this potential limitation, we have built an improved seven‐locus set of methylation markers that includes CACNA1G, IGF2, RUNX3, HTR6, RIZ1, MINT31, and MAP1B. This new set of CIMP markers revealed a bimodal distribution of methylation frequencies in a group of 95 MSS colorectal cancers, which allowed a clearer separation between CIMP classes. Correlation of MSS CIMP+ tumours with bio‐pathological traits revealed significant associations with location to the proximal colon, mucinous histology, BRAF mutation, and chromosomal stability. A potential trend towards an adverse prognosis of CIMP+ cases was associated with the high frequency of BRAF mutations present within this cohort of tumours. Microarray analysis revealed that CIMP+ tumours are characterized by a unique expression profile, a result that confirms that CIMP+ tumours represent a truly distinct molecular class within MSS colorectal cancers. Copyright © 2008 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
PATZ1 gene has a critical role in the spermatogenesis and testicular tumours
Authors: Fedele M , Franco R , Salvatore G , Paronetto MP , Barbagallo F , Pero R , Chiariotti L , Sette C , Tramontano D , Chieffi G , Fusco A , Chieffi P
Published: February 2008

PATZ1 is a recently discovered zinc finger protein that, due to the presence of the POZ domain, acts as a transcriptional repressor affecting the basal activity of different promoters. To gain insights into its biological role, we generated mice lacking the PATZ1 gene. Male PATZ1−/− mice were unfertile, suggesting a crucial role of this gene in spermatogenesis. Consistently, most of adult testes from these mice showed only few spermatocytes, associated with increased apoptosis, and complete absence of spermatids and spermatozoa, with the subsequent loss of tubular structure. The analysis of PATZ1 expression, by northern blot, western blot and immunohistochemistry, revealed its presence in Sertoli cells and, among the germ cells, exclusively in the spermatogonia. Since PATZ1 has been indicated as a potential tumour suppressor gene, we also looked at its expression in tumours deriving from testicular germ cells (TGCTs). Although expression of PATZ1 protein was increased in these tumours, it was delocalized in the cytoplasm, suggesting an impaired function. These results indicate that PATZ1 plays a crucial role in normal male gametogenesis and that its up‐regulation and mis‐localization could be associated to the development of TGCTs. Copyright © 2008 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Glutamate and schizophrenia: new insights, new treatments
Authors: Greener Mark
Published: February 2008

There is increasing evidence to suggest that dopamine may not be as central to the pathogenesis of schizophrenia as previously believed. Here, Mark Greener provides an overview of studies supporting the primary role of glutamate in the development of schizophrenia and discusses its potential as a novel therapeutic target. Copyright © 2008 Wiley Interface Ltd
Ring‐chain interconversion of sulforhodamine‐amine conjugates involves an unusually labile CN bond and allows measurement of sulfonamide ionization kinetics
Authors: Corrie John E. T. , Eccleston John F. , Ferenczi Michael A. , Moore Madeleine H. , Turkenburg Johan P. , Trentham David R.
Published: February 2008

pH‐dependent interconversion between ring and chain forms of sultams/sulfonamides derived from conjugates of sulforhodamines with amines, and the associated sulfonamide ionization, have been studied by a combination of equilibrium and kinetic methods. The colorless, ring‐closed sultam form is favored at alkaline pH with an apparent pKa of 7.37 for the color change of the methylamine conjugate of Sulforhodamine B. The ring‐closed form is also favored at very low pH (apparent pKa ∼ 0.68) by protonation of both diethylamino substituents. The kinetics of interconversion between open and closed forms were measured at 4°C over the pH range 0–13. The observed rate constant ranges over nine orders of magnitude from 4.8 × 10−4 s−1 at pH 1 to 2.27 × 106 s−1 at pH ≥ 12. Above pH 2, the data are accommodated by a mechanism that includes cleavage of the sultam CN bond in the ring opening step with a sulfonamide anion as the leaving group, and in the reverse reaction, OH−‐dependent ionization of the sulfonamide at 4.8 (±2.0) × 109 M−1 s−1. Below pH 2, H+‐dependent protonation occurs at 1.4 (±0.4) × 10−3 M−1 s−1. X‐ray crystallography of a related N‐methylsultam showed that the labile, endocyclic CN bond is significantly longer than the exocyclic NCH3 bond (1.509 Å and 1.445 Å, respectively). Laser‐induced ring opening of the closed form has potential application as an orientation probe of biological macromolecules. Copyright © 2008 John Wiley & Sons, Ltd.
Synthesis of a novel poly(para‐phenylene ethynylene) for highly selective and sensitive sensing mercury (II) ions
Authors: Li Cuihong , Zhou Chunjie , Zheng Haiyan , Yin Xiaodong , Zuo Zicheng , Liu Huibiao , Li Yuliang
Published: February 2008

A new poly(p‐phenylene ethynylene) derivative with pendant 2,2′‐bipyridyl groups and glycol units (PPE‐bipy) has been prepared, and its metal ion sensing properties were investigated. The polymer of PPE‐bipy exhibited high selectivity for Hg2+ as compared with Li+, Na+, K+, Ba2+, Ca2+, Mg2+, Al3+, Mn2+, Ag+, Zn2+, Pb2+, Ni2+, Cd2+, Cu2+, Co,2+ and Fe3+ in THF/EtOH (1:1, v/v) solution. The fluorescence of PPE‐bipy was efficiently quenched by Hg2+ ions, and the detection limit was found to be 8.0 nM in a THF/EtOH (1:1, v/v) solvent system. PPE‐bipy also showed a selective chromogenic behavior toward Hg2+ ions by changing the color of the solution from slight yellow to colorless, which can be detected with the naked eye. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 1998–2007, 2008
Initialization behavior at various target molecular weight RAFT‐mediated methyl acrylate polymerizations
Authors: van den Dungen Eric T. A. , Matahwa Howard , McLeary James B. , Sanderson Ronald D. , Klumperman Bert
Published: February 2008

In the reversible addition‐fragmentation chain transfer (RAFT) mediated polymerization of methyl acrylate, a selective reaction is observed in the early stages of the polymerization. This initialization process was earlier observed in in situ 1H NMR spectroscopy experiments where extremely low target molar masses were chosen (around DP = 5). Here, for the first time, the presence of the initialization process is identified as the cause of an induction period under typical conditions of a RAFT‐mediated polymerization. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 2500–2509, 2008
Ultrafast SET‐LRP of methyl acrylate at 25 °C in alcohols
Authors: Lligadas Gerard , Percec Virgil
Published: February 2008

Alcohols are known to promote the disproportionation of Cu(I)X species into nascent Cu(0) and Cu(II)X. Therefore, alcohols are expected to be excellent solvents that facilitate the single‐electron transfer mediated living radical polymerization (SET‐LRP) mediated by nascent Cu(0) species. This publication demonstrates the ultrafast SET‐LRP of methyl acrylate initiated with bis(2‐bromopropionyloxy)ethane and catalyzed by Cu(0)/Me6‐TREN in methanol, ethanol, 1‐propanol, and tert‐butanol and in their mixture with water at 25 °C. The structural analysis of the resulting polymers by a combination of 1H NMR and MALDI‐TOF MS demonstrates the synthesis of perfectly bifunctional α,ω‐dibromo poly(methyl acrylate)s by SET‐LRP in alcohols. Moreover, this work provides an expansion of the list of solvents available for SET‐LRP. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 2745–2754, 2008
Polyethylene terephthalate–multiwall nanotubes nanocomposites: Effect of nanotubes on the conformations, crystallinity and crystallization behavior of PET
Authors: Tzavalas Spiros , Mouzakis Dionysis E. , Drakonakis Vasilis , Gregoriou Vasilis G.
Published: February 2008

PET‐nanotube composite samples were manufactured by mixing neat PET with a PET‐multiwall carbon nanotube masterbatch. Fourier transform infrared (FTIR) spectroscopy was utilized to monitor the gauche and trans conformations of the polymeric chains with respect to the nanotube content. The crystallinity as well as the crystallization behavior of the polymer were studied via differential scanning calorimetry (DSC). An increase of the trans conformations and crystallinity was recorded at low NT contents followed by a sharp decrease at 1 wt % of nanotubes, further addition of nanotubes led once again to increase of the trans conformations and crystallinity. This behavior was attributed to the aggregations formation which as shown via transmission electron microscopy (TEM) was initiated at concentrations above 0.5 wt %. Discordance between the FTIR and DSC results in the case of the PET sample showed that the later bears relatively more trans non‐crystalline conformers than the nanocomposite samples. Thus it appears that the nanotubes incorporate the trans non‐crystalline segments into the crystalline phase. This work has shown that even a minor addition of carbon nanotubes (even 0.1 wt %) alters the crystallization behavior of the polymer dramatically, yielding a novel nanocomposite material rather than a simple mixture of two ingredients. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 668–676, 2008
Fine structure of PVDF nanofiber fabricated by electrospray deposition
Authors: Danno T. , Matsumoto H. , Nasir M. , Shimizu S. , Minagawa M. , Kawaguchi J. , Horibe H. , Tanioka A.
Published: February 2008

The fine structure of poly(vinylidene fluoride) (PVDF) nanofiber prepared by electrospray deposition (ESD) has been investigated by wide angle X‐ray diffraction (WAXD) and infrared spectroscopy (IR). The β‐phase crystal was dominant in the crystalline region. The degree of crystallinity of 0.54 for the nanofiber, determined by Ruland's method, was almost identical to that for a melt pressed sheet of PVDF. The disorder parameter k was 4, which is significantly smaller than the value of 6 for the melt pressed sheet of PVDF. Molecular orientation along the fiber axis was observed by the polarized infrared spectra of the uniaxially aligned nanofiber. These results suggest that the PVDF nanofiber possesses a fiber structure which is by no means inferior to that of practical fibers. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 558–563, 2008
Templated synthesis of silver nanoparticles in amphiphilic poly(vinylidene fluoride‐co‐chlorotrifluoroethylene) comb copolymer
Authors: Koh Joo Hwan , Kim Yong Woo , Park Jung Tae , Kim Jong Hak
Published: February 2008

In this study, poly(vinylidene fluoride‐co‐chlorotrifluoroethylene)‐graft‐poly(oxyethylene methacrylate), P(VDF‐co‐CTFE)‐g‐POEM, an amphiphilic comb copolymer with hydrophobic P(VDF‐co‐CTFE) backbone and hydrophilic POEM side chains at 73:27 wt % was synthesized. The POEM side chains were grafted from the P(VDF‐co‐CTFE) mainchain backbone via atom transfer radical polymerization (ATRP) using direct initiation of the chlorine atoms in CTFE units. Synthesis of microphase‐separated P(VDF‐co‐CTFE)‐g‐POEM comb copolymer was successful, as confirmed by nuclear magnetic resonance (1H NMR), FTIR spectroscopy, and transmission electron microscopy (TEM). Nanocomposite films were prepared using the comb copolymer as a template film and the in situ reduction of AgCF3SO3 precursor to silver nanoparticles under UV irradiation. Silver nanoparticles with 4–8 nm in average size were in situ created in the solid state template film, as revealed by TEM, UV–visible spectroscopy, and wide angle X‐ray scattering (WAXS). Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) presented the selective incorporation and the in situ growth of silver nanoparticles within the hydrophilic POEM domains of microphase‐separated comb copolymer film. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 702–709, 2008
Stimulus response and molecular structural modification of polyacrylamide gel in nitric acid: A study by Raman, FTIR, and photoluminescence techniques
Authors: Sivanantham M. , Kesavamoorthy R. , Sairam T. N. , Sabharwal K. N. , Raj Baldev
Published: February 2008

Stimulus response of photopolymerized 1% and 0.5% N,N′‐methylene bisacrylamide (MBA) crosslinked 10% polyacrylamide (PAAm) hydrogels was studied in nitric acid. The hydrogels swelled exponentially to saturation in 13 h due to the osmotic pressure arising from diffusion of ions in to the gel. MBA (0.5%) gels swell more with larger time constant than 1% MBA gels due to lower bulk modulus. Diffusion coefficient of nitric acid in the hydrogel and polymer‐solvent interaction parameter were estimated from the swelling behavior and discussed. At longer times, the hydrogels deswelled linearly in nitric acid due to molecular modification of amide group by acidic hydrolysis. Degree of swelling and deswelling increase with nitric acid concentration. Raman and FTIR investigations revealed the formation of carboxylic acid due to acidic hydrolysis. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 710–720, 2008
Synthesis, characterization, and properties of monodispersed magnetite coated multi‐walled carbon nanotube/polypyrrole nanocomposites synthesized by in‐situ chemical oxidative polymerization
Authors: Wu Tzong‐Ming , Yen Shiang‐Jie , Chen Erh‐Chiang , Chiang Ray‐Kuang
Published: February 2008

This study describes the preparation of a nanocomposites fabricated from monodispersed 4‐nm iron oxide (Fe3O4) coated on the surface of carboxylic acid containing multi‐walled carbon nanotube (c‐MWCNT) and polypyrrole (PPy) by in situ chemical oxidative polymerization. High‐resolution transmission electron microscopy images and X‐ray diffraction (XRD) data indicate that the resulting Fe3O4 nanoparticles synthesized using the thermal decomposition are close to spherical dots with a particle size about 4 ± 0.2 nm. The resulting nanoparticles were further mixed with c‐MWCNT in an aqueous solution containing with anionic surfactant sodium bis(2‐ethylhexyl) sulfosuccinate to form one‐dimensional Fe3O4 coated c‐MWCNT template for further preparation of nanocomposite. Structural and morphological analysis using field‐emission scanning electron microscopy, high‐resolution transmission electron microscopy, and XRD showed that the fabricated Fe3O4 coated c‐MWCNT/PPy nanocomposites are one‐dimensional core (Fe3O4 coated c‐MWCNT)‐shell (PPy) structures. The conductivities of these Fe3O4 coated c‐MWCNT/PPy nanocomposites are about four times higher than those of pure PPy matrix. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 727–733, 2008
The UGT2B17 gene deletion is not associated with prostate cancer risk
Authors: Olsson Mats , Lindström Sara , Häggkvist Benjamin , Adami Hans‐Olov , Bälter Katarina , Stattin Pär , Ask Birgitta , Rane Anders , Ekström Lena , Grönberg Henrik
Published: February 2008

BACKGROUND

Deletion polymorphism of the UDP‐glucuronosyltransferase 2B17 (UGT2B17) gene has been associated with an increased prostate cancer risk in two previous independent studies. Here we determine the risk in a large‐scale population‐based case–control study.

METHODS

Genotyping was conducted with a 5′‐nuclease activity assay to distinguish those with one or two UGT2B17 gene copies (ins/del and ins/ins) from individuals homozygous for the deletion (del/del) allele.

RESULTS

In contrast to previous findings, no association between the UGT2B17 deletion polymorphism and prostate cancer risk was found. Furthermore the UGT2B17 gene deletion did not affect the risk for prostate cancer specific death.

CONCLUSION

The UGT2B17 deletion polymorphism does not play a major role in prostate cancer susceptibility as previously indicated. Prostate 68: 571–575, 2008. © 2008 Wiley‐Liss, Inc.
Prostate cancer in Mexican‐Americans: Identification of risk factors
Authors: Strom Sara S. , Yamamura Yuko , Flores‐Sandoval F. Nery , Pettaway Curtis A. , Lopez David S.
Published: February 2008

BACKGROUND

There is a paucity of information regarding prostate cancer (PCa) risk factors among Hispanics, the fastest‐growing ethnic group in the United States.

METHODS

This population‐based case‐control study included 176 Texas men of Mexican descent with PCa and 174 age‐ and ethnicity‐matched controls. Demographic, lifetime occupational history, family history of cancer, lifestyle (e.g., smoking, alcohol, diet, and recreational physical activity) and anthropometric information were collected by personal interviews. Chemical exposure and physical activity were determined using job‐exposure matrices for each reported job.

RESULTS

Logistic regression models adjusted for relevant covariates were used to evaluate their independent effects. Compared to controls, cases were three times more likely to work in jobs with high agrichemical exposure (OR = 3.44, 95% CI 1.84–6.44), and 54% less likely to work in jobs with moderate/high occupational physical activity (OR = 0.46, 95% CI 0.28–0.77). In analyses stratified by stage, cases with organ‐confined PCa were three times more likely to have high agrichemical exposure (OR = 3.39, 9%CI 1.68–6.84), and 56% less likely to have moderate/high levels of occupational physical activity (OR = 0.44, 95% CI 0.26–0.76). Increased risk of being diagnosed with advanced PCa was associated with obesity at time of diagnosis (OR = 2.50, 95% CI 1.20–5.20) and high levels of agrichemical exposure (OR = 4.65, 95% CI 1.97–10.97), but not with occupational physical activity.

CONCLUSIONS

This case‐control study, the first conducted in a homogeneous Hispanic population, identified modifiable PCa risk factors, such as physical activity and agrichemical exposure, which may be useful in developing interventions for this understudied population. Prostate 68: 563–570, 2008. © 2008 Wiley‐Liss, Inc.