bluuebunny/crossref_metadata_2025 huggingface dataset:
Promoter methylation profile in preneoplastic and neoplastic gallbladder lesions
Authors: García Patricia , Manterola Carlos , Araya Juan Carlos , Villaseca Miguel , Guzmán Pablo , Sanhueza Antonio , Thomas Melanie , Alvarez Héctor , Roa Juan Carlos
Published: June 2008

Gallbladder carcinoma (GBC) is a highly malignant neoplasm and represents the leading cause of cancer death in Chilean women. In order to determine the potential role of promoter methylation in gallbladder carcinogenesis, we investigated the frequency of this epigenetic mechanism by methylation‐specific polymerase chain reaction (MSP) in 35 chronic cholecystitis (CC, separated according to the presence or absence of metaplasia), 19 early cancers (mucosa or muscularis propia invasion) and 48 advanced carcinomas with invasion of the gallbladder subserosa (25 cases) and serosa (23 cases). We examined 14 genes and observed an increase of multigenic methylation during tumoral progression which was not significantly associated with the patient's age. Four genes (DAPK1, DLC1, TIMP3, and RARβ2) displayed a progressive increase in their methylation status from CC without metaplasia to advanced carcinoma invading the serosa layer (P ≤ 0.05). The survival analysis indicated that a methylated condition of DLC1 gene is significantly associated with poor prognosis (P = 0.04), whereas a methylated state of MGMT gene correlated with better patient survival (P = 0.006). Our findings indicate that aberrant hypermethylation of promoter regions is an early, progressive and cumulative event in gallbladder carcinogenesis. Furthermore, the methylation levels seems to accumulate in the progression of CC without metaplasia to CC with metaplasia, a fact that could provide new evidence to consider this morphological adaptation of GB mucosa as a premalignant lesion. Finally, the methylation status of some individual genes could be useful biomarkers with potential clinical application in diagnosis or prognosis of GBC if they are validated in a greater number of clinical samples. © 2008 Wiley‐Liss, Inc.
Cognitive dysfunction in Nigerians with Parkinson's disease
Authors: Akinyemi Rufus O. , Okubadejo Njideka N. , Akinyemi Joshua O. , Owolabi Mayowa O. , Owolabi Lukman F. , Ogunniyi Adesola
Published: June 2008

Despite the original description of Parkinson's disease (PD) as a disorder in which “the senses and intellect remain uninjured,” there is now sufficient evidence that cognitive dysfunction does occur. This research determined the frequency, pattern, and predictors of cognitive dysfunction among 51 Nigerian patients with PD compared with 50 demographically matched controls using the modified Community Screening Instrument for Dementia (CSI‘D’) and selected items from the Ibadan Neuropsychological Battery (I‐NB). In all, 21.6% patients with PD (4% of controls) exhibited cognitive impairment (P = 0.008) defined, for the purposes of this study, as total modified CSI‘D’ score below 2 SD of the mean score of the control group. Cognitive dysfunction in patients with PD encompassed memory, language, and executive dysfunction. Correlates of cognitive dysfunction included older age at PD onset (P = 0.001), older current age (P < 0.001), and higher UPDRS motor score (P = 0.005). After logistic regression, older age at onset of PD was the only independent predictor of cognitive dysfunction. (O.R = 1.29; 95% CI = 1.08–1.57, P = 0.006). Cognitive dysfunction occurs more frequently in Nigerians with PD compared to controls. Older age at disease onset is an important determinant of cognitive dysfunction in PD. © 2008 Movement Disorder Society
Familial Parkinsonism with digenic parkin and PINK1 mutations
Authors: Funayama Manabu , Li Yuanzhe , Tsoi Tak‐Hong , Lam Ching‐Wan , Ohi Takekazu , Yazawa Shogo , Uyama Eiichiro , Djaldetti Ruth , Melamed Eldad , Yoshino Hiroyo , Imamichi Yoko , Takashima Hiroshi , Nishioka Kenya , Sato Kenichi , Tomiyama Hiroyuki , Kubo Shin‐Ichiro , Mizuno Yoshikuni , Hattori Nobutaka
Published: June 2008

To clarify the genetic correlation between parkin and PINK1, we screened for PINK1 mutations in 175 parkinsonism patients with parkin mutations. We detected two sibling pairs and one sporadic patient carrying both parkin and PINK1 mutations. The age at onset of Parkinsonism of patients with the digenic mutations was lower than that of patients with the same parkin mutation alone. In addition, two of three patients carrying both parkin and PINK1 mutations had schizophrenia. These findings indicate that PINK1 mutation might modify parkin mutation‐positive Parkinsonism, and PINK1 mutations might be associated withpsychiatric disorders. © 2008 Movement Disorder Society
Long‐term treatment with botulinum toxin type A in cervical dystonia has low immunogenicity by mouse protection assay
Authors: Brin Mitchell F. , Comella Cynthia L. , Jankovic Joseph , Lai Francis , Naumann Markus
Published: June 2008

To evaluate the immunogenicity of botulinum toxin type A (BoNTA; BOTOX) in cervical dystonia (CD). Subjects diagnosed with CD for ≥1 year and previously naïve to BoNTs were treated with BoNTA in a prospective, open‐label, multicenter study. Serum samples were analyzed for BoNTA neutralizing antibodies using the Mouse Protection Assay (MPA). Clinical resistance was assessed with a test injection of 20 U BoNTA placed unilaterally into the frontalis (Frontalis Antibody Test; FTAT) or corrugator muscle (Unilateral Brow Injection; UBI). Efficacy was assessed and adverse events were recorded. Of 326 subjects enrolled, 251 (77%) completed the study. Subjects received a median of 9 BoNTA treatments (mean dose per session ranged from 148.4 to 213.0 U over a mean of 2.5 years [range: 3.2 months–4.2 years]). Only 4 of 326 subjects (1.2%) tested positive for antibodies in the MPA; three of these subjects stopped responding clinically to BoNTA (of whom one also showed clinical resistance in the FTAT) and one continued to respond. Consistent improvements in the signs/symptoms of CD were noted. The most frequent treatment‐related adverse events were mild to moderate weakness, dysphagia, neck pain, and injection‐site pain. The current formulation of BoNTA rarely causes neutralizing antibody formation in CD subjects treated ≤4 years. © 2008 Movement Disorder Society
Entacapone improves absorption of a coadministered salt in patients with Parkinson's disease
Authors: Müller Thomas , Woitalla Dirk , Goetze Oliver , Erdmann Christoph
Published: June 2008

Entacapone (EN) improves the efficacy of levodopa/dopadecarboxylase inhibitor (LD/DDI) formulations by inhibition of the enzyme catechol‐O‐methyltransferase (COMT). COMT inhibition also promotes the synthesis of basic LD metabolites, whereas DDI support the composition of acidic LD derivatives. LD metabolism correlates to the one of 13C‐sodium‐octanoate, which is employed in breath tests to measure gastric emptying velocity. Objectives were to investigate the impact of COMT inhibition on the recovery rate of 13C‐sodium‐octanoate in parkinsonian patients, who received first 100 mg LD/Carbidopa (CD) and the next day 100 mg LD/CD/EN combined with 13C‐sodium‐octanoate in each case. The recovery rate of 13C‐sodium‐octanoate was significant higher during the LD/CD/EN–compared with the LD/CD condition. COMT inhibition combined with LD/DDI improves absorption of a co‐administered salt probably due to a COMT inhibition induced basic environment in gastrointestinal membranes. This improves dissolution and absorption of acids and salts. Thus it may enhance absorption of LD itself. © 2008 Movement Disorder Society
Transgenic medaka enables easy oocytes detection in live fish
Authors: Kinoshita Masato , Okamoto Gensei , Hirata Takashi , Shinomiya Ai , Kobayashi Tohru , Kubo Yuko , Hori Hiroshi , Kanamori Akira
Published: June 2008

Easy oocyte detection in living specimens benefits various developmental biology and environmental toxicology studies. One of the earliest markers of sex differentiation in medaka (Oryzias latipes) is oocyte development. Within the field of toxicology, a simple detection method for induced oocyte in the testis (testis‐ova) as a result of endocrine disruption is necessary. In this study we produced transgenic medaka whose oocytes were labeled with fluorescent proteins using the regulatory region of the 42Sp50 gene, an isoform of polypeptide elongation 1‐alpha. Short (201 nt) 5′‐ and 3′‐flanking regions were sufficient for reporter gene expression. GFP expression was first observed in female germ cells approximately 5 days post‐hatching. In the mature ovaries, germ cells showed such intense fluorescence that the fluorescence was observed from outside the body wall. In contrast, very faint fluorescence was observed in the mature testes. Testis‐ova, oocytes artificially induced in the testes, were also labeled with GFP. These findings indicate through the use of transgenic medaka, that detection of female germ cells was straightforward and this transgenic medaka model proves useful for tracking female germ cells in developmental and toxicological studies. Mol. Reprod. Dev. 76: 202–207, 2009. © 2008 Wiley‐Liss, Inc.
Meta‐analysis of the effects of exercise interventions on functional status in older adults
Authors: Gu Mee Ock , Conn Vicki S.
Published: June 2008

A meta‐analysis was conducted to quantify the impact of exercise interventions on the functional status of older adults. Searches of Medline and CINAHL databases revealed 19 randomized controlled trials reporting 30 interventions (n = 2,201). Fixed‐ and random‐effects models were used to estimate overall mean effect sizes (ESs) for functional and physical performance outcomes and activities of daily living (ADL). Modest but statistically significant ESs were found for functional performance and physical performance but not for ADL. Exercise improved functional and physical performance but the improvement may be insufficient to have an impact on ADL. Further studies are needed to determine exercise's effects on ADL and to identify moderators associated with functional status outcomes in older adults. © 2008 Wiley Periodicals, Inc. Res Nurs Health 31:594–603, 2008
The dynamics of poverty in the United States: A review of data, methods, and findings
Authors: Cellini Stephanie Riegg , McKernan Signe‐Mary , Ratcliffe Caroline
Published: June 2008

This paper reviews the literature on poverty dynamics in the U.S. It surveys the most prevalent data, theories, and methods used to answer three key questions: How likely are people to enter, exit, and reenter poverty? How long do people remain in poverty? And what events are associated with entering and exiting poverty? The paper then analyzes the combined findings of the literature, discussing overarching patterns of poverty dynamics, differences among demographic groups, and how poverty probabilities, duration, and events have changed over time. We conclude with a discussion of the policy implications of these findings and avenues for future research. © 2008 by the Association for Public Policy Analysis and Management.
Marriage patterns among unwed mothers: Before and after PRWORA
Authors: Graefe Deborah Roempke , Lichter Daniel T.
Published: June 2008

The promotion of marriage and two‐parent families became an explicit public policy goal with the passage of the 1996 welfare reform bill. Marriage has the putative effect of reducing welfare dependency among single mothers, but only if they marry men with earnings sufficient to lift them and their children out of poverty. Newly released data from the 2002 cycle of the National Survey of Family Growth (NSFG), along with data from the 1995 cycle, allow us to compare pre‐ and post‐PRWORA differences in (1) cumulative marriage rates among unwed mothers, and (2) patterns of marital choice (that is, differences in characteristics of the men these mothers marry, such as their education and employment status). Overall, our results show that unwed childbearing is associated with lower marriage rates and marital quality. Difference‐in‐difference models show that welfare reform was not strongly associated with pre‐ and post‐welfare reform changes in marriage among nonmarital birth mothers, even among the most disadvantaged mothers. Compared with other women, nonmarital birth mothers also were less likely than other women to marry “economically attractive” men in the post‐welfare reform period. The success of marriage promotion initiatives may depend heavily on whether women themselves are “marriageable” and whether potential spouses have the ability to support a stable family life. © 2008 by the Association for Public Policy Analysis and Management.
The effects of an employer subsidy on employment outcomes: A study of the work opportunity and welfare‐to‐work tax credits
Authors: Hamersma Sarah
Published: June 2008

Employer subsidies such as the Work Opportunity Tax Credit (WOTC) and the Welfare‐to‐Work Tax Credit (WtW) are designed to encourage employment by partially reimbursing employers for wages paid to certain welfare recipients and other disadvantaged workers. In this paper, I examine the effects of these subsidies on employment, wages, and job tenure using unique administrative data from Wisconsin. My ability to precisely identify the subsidy‐certified workers allows me to distinguish the effects of program participation from mere eligibility. Using propensity score matching estimation, I find some evidence of short‐term improvements in labor market outcomes, but little evidence of sustained benefits. © 2008 by the Association for Public Policy Analysis and Management.
Nanofiller‐reinforced polymer nanocomposites
Authors: Njuguna J. , Pielichowski K. , Desai S.
Published: June 2008

In this work, the technology of nano‐ and micro‐scale particle reinforcement concerning various polymeric fiber‐reinforced systems including polyamides (PAs), polyesters, polyurethanes (PUs), polypropylenes
(pps), and high‐performance/temperature engineering polymers such as polyimide (PI), poly(ether ether ketone) (PEEK), polyarylacetylene (PAA), and poly p‐phenylene benzobisoxazole (PBO) is reviewed. When the diameters of polymer fiber materials are shrunk from micrometers to submicrons or nanometers, there appear several unique characteristics such as very large surface area to volume ratio (this ratio for a nanofiber can be as large as 103 times of that of a microfiber), flexibility in surface functionalities and superior mechanical performance (such as stiffness and tensile strength) compared to any other known form of the material. While nanoparticle reinforcement of fiber‐reinforced composites has been shown to be a possibility, much work remains to be performed in order to understand how nanoreinforcement results in dramatic changes in material properties. The understanding of these phenomena will facilitate their extension to the reinforcement of more complicated anisotropic structures and advanced polymeric composite systems. Copyright © 2008 John Wiley & Sons, Ltd.
Synthesis of ω‐anthracenyl‐functionalized soluble polyphenylene: effect of the end‐group on optical and electrical properties
Authors: Natori Itaru , Natori Shizue , Sasaki Shiori , Sekikawa Hiroyuki , Sato Hisaya
Published: June 2008

ω‐Anthracenyl‐functionalized soluble polyphenylene (AN‐SPP) with a well‐controlled polymer chain was synthesized. The optical and electrical properties were strongly affected by the anthracenyl end‐group. The UV absorption and photoluminescence emission were enhanced and shifted toward the longer wavelength region in comparison to that of soluble polyphenylene. The optical band gap energies of the main chain and the anthracenyl end‐group were 3.15 and 3.89 eV, respectively. The highest occupied molecular orbital/lowest unoccupied molecular orbital energy levels of the main chain and the anthracenyl end‐group of AN‐SPP were −4.98/−1.81 eV and −7.25/−3.36 eV, respectively. The current–voltage characteristics of AN‐SPP were controllable by the presence of the anthracenyl end‐group. Copyright © 2008 John Wiley & Sons, Ltd.
Photo‐induced polymerization of methyl methacrylate/cyclodextrin complex in aqueous solution
Authors: Deng Jianping , Wu Zhilin , He Qinxiong , Yang Wantai
Published: June 2008

Polymerization of hydroxypropyl‐β‐cyclodextrin (HP‐β‐CD) complex of methyl methacrylate (MMA) (MMA/HP‐β‐CD) was carried out under UV irradiation in aqueous solution with Irgacure 2959 (4‐(2‐hydroxyethoxy)phenyl‐(2‐hydroxy‐2‐propyl)ketone) as a photoinitiator at room temperature. The effects of some principal factors, including UV irradiation intensity, initiator concentration, and the ratio of HP‐β‐CD to MMA, on the polymerization were investigated in detail. Compared to the corresponding thermal polymerization, photo‐induced polymerization of the MMA/HP‐β‐CD complex could be accomplished at a higher speed; the polymerization conversion in photo‐induced polymerization reached 94% within 30 min, while it was only 62% for the thermal polymerization of 16 hr at 70°C. The number‐average molecular weight (Mn) and polymerization conversion decreased with the increase in UV intensity and initiator concentration. The resulting PMMA precipitated spontaneously from the solution during polymerization in the absence of any precipitator. About 95 wt% of the HP‐β‐CD remained in the solution after polymerization and the reusability of the residual HP‐β‐CD was experimentally demonstrated. Copyright © 2008 John Wiley & Sons, Ltd.
High‐temperature and high‐pressure ethylene polymerization using a cationic activated metallocene catalytic system
Authors: de Oliveira Otanéa Brito , Brandão Soraia Teixeira , de Freitas Alan John Duarte , da Silva Eleny Pires , Meneghetti Simoni Margareti Plentz , Meneghetti Mario Roberto
Published: June 2008

BACKGROUND: Normally, olefin polymerization via metallocene‐based catalysis occurs under mild conditions. However, most technology developed for polyolefin production is designed for more severe temperature and pressure processes. Attaining more thermally stable metallocene systems for industrial applications is an important challenge for researchers.

RESULTS: A systematic study of ethylene homopolymerization at higher temperatures and pressures, employing the ternary system Ph2C(Cp)(Flu)ZrCl2/PhNHMe2B(C6F5)4/(i‐Bu)3Al, is presented The optimal activity for this system is achieved with a Zr/B/Al molar ratio of 1/6/250 and a temperatures of around 130 °C. However, the amount of activator strongly affects the molecular weight and the polydispersity of the polymers produced. Polyethylene produced with Zr/B/Al molar ratios between 1/2/250 and 1/6/250 show no significant difference in their temperature of fusion (Tm) and their crystallinity (Xc). In contrast, in the presence of activator amounts higher than 1/6/250, both the temperature of fusion and polymer crystallinity undergo a steep decrease. All polymers presented lamellar morphology when the activator was present, and an amorphous aspect when the activator was not employed.

CONCLUSION: The presence of the activator is essential for thermal stabilization of the catalytic system. Variation of the Zr/B/Al ratio leads to modifications of the catalytic activity as well as to the properties of the polymers synthesized. Copyright © 2008 Society of Chemical Industry
Articles published in four school psychology journals from 2000 to 2005: An analysis of experimental/intervention research
Authors: Bliss Stacy L. , Skinner Christopher H. , Hautau Briana , Carroll Erin E.
Published: June 2008

Using an experimenter‐developed system, articles from four school psychology journals for the years 2000–2005 (n = 929) were classified. Results showed that 40% of the articles were narrative, 29% correlational, 16% descriptive, 8% causal‐experimental, 4% causal‐comparative, and 2% were meta‐analytic. Further analysis of the causal‐experimental studies suggested that both single‐subject and group designs were used to evaluate the effects of interventions delivered in schools (setting data) that improved students' (participant data) academic and/or social behaviors (target behavior data). Although results show that these journals are publishing few experimental studies, the experiments that are published appear to be derived from field‐based research evaluating interventions that readers may find useful for remedying problems in school settings. Discussion focuses on factors that may limit experimental studies and recent trends in education and school psychology. © 2008 Wiley Periodicals, Inc.
Proteomic investigation of amino acid catabolism in the indigenous gut anaerobe Fusobacterium varium
Authors: Potrykus Joanna , White Robert L. , Bearne Stephen L.
Published: June 2008

The butyrate‐producing anaerobe Fusobacterium varium is an integral constituent of human gut microflora. Unlike many gut microorganisms, F. varium is capable of fermenting both amino acids and glucose. Although F. varium has been implicated in beneficial as well as pathological bacterium–host interactions, its genome has not been sequenced. To obtain a better understanding of the metabolic processes associated with amino acid fermentation by F. varium, we used a gel‐based proteomic approach to examine the changes in the soluble proteome accompanying the utilization of eight different growth substrates: glucose, L‐ and D‐glutamate, L‐histidine, L‐ and D‐lysine, and L‐ and D‐serine. Using LC‐MS/MS to analyze ˜25% of the detected protein spots, we were able to identify 47 distinct proteins. While the intracellular concentrations of enzymes characteristic of a catabolic pathway for a specific amino acid were selectively increased in response to the presence of an excess of that amino acid in the growth medium, the concentrations of the core acetate–butyrate pathway enzymes remained relatively constant. Our analysis revealed (i) high intracellular concentrations of glutamate mutase and β‐methylaspartate ammonia‐lyase under all growth conditions, underscoring the importance of the methylaspartate pathway of glutamate catabolism in F. varium (ii) the presence of two enzymes of the hydroxyglutarate pathway of glutamate degradation in the proteome of F. varium ((R)‐2‐hydroxyglutaryl‐CoA dehydratase and NAD‐specific glutamate dehydrogenase) specifically when L‐glutamate was the main energy source (iii) the presence of genes in the genome of F. varium encoding each of the enzymes of the hydroxyglutarate pathway (iv) the presence of both L‐ and D‐serine ammonia‐lyases (dehydratases) which permit F. varium to thrive on either L‐ or D‐serine, respectively, and (v) the presence of aspartate‐semialdehyde dehydrogenase and dihydrodipicolinate synthase, consistent with the ability of F. varium to synthesize meso‐2,6‐diaminopimelic acid as a component of its peptidoglycan. Proteins involved in other cellular processes, including oxidation–reduction reactions, protein synthesis and turnover, and transport were also identified.
Proteomic profiling of CHO cells with enhanced rhBMP‐2 productivity following co‐expression of PACEsol
Authors: Meleady Paula , Henry Michael , Gammell Patrick , Doolan Padraig , Sinacore Martin , Melville Mark , Francullo Linda , Leonard Mark , Charlebois Timothy , Clynes Martin
Published: June 2008

Chinese hamster ovary (CHO) cells are widely used for the production of recombinant protein biopharmaceuticals. The purpose of this study was to investigate differences in the proteome of CHO DUKX cells expressing recombinant human bone morphogenetic protein‐2 (rhBMP‐2) (G5 cells) compared to cells also expressing soluble exogenous paired basic amino acid cleaving enzyme soluble paired basic amino acid cleaving enzyme (PACEsol) (3C9 cells), which has been previously found to improve the post‐translational processing of the mature rhBMP‐2 dimer. PACEsol co‐expression was also associated with a significant increase (almost four‐fold) in cellular productivity of rhBMP‐2 protein. Differential proteomic expression profiling using 2‐D DIGE and MALDI‐TOF MS was performed to compare 3C9 and G5 cells, and revealed a list of 60 proteins that showed differential expression (up/downregulated), with a variety of different cellular functions. A substantial number of these altered proteins were found to have chaperone activity, involved with protein folding, assembly and secretion, as well as a number of proteins involved in protein translation. These results support the use of proteomic profiling as a valuable tool towards understanding the biology of bioprocess cultures.
Proteomics in Trypanosoma cruzi – localization of novel proteins to various organelles
Authors: Ferella Marcela , Nilsson Daniel , Darban Hamid , Rodrigues Claudia , Bontempi Esteban J. , Docampo Roberto , Andersson Björn
Published: June 2008

The completion of the genome sequence of Trypanosoma cruzi has been followed by several studies of protein expression, with the long‐term aim to obtain a complete picture of the parasite proteome. We report a proteomic analysis of an organellar cell fraction from T. cruzi CL Brener epimastigotes. A total of 396 proteins were identified by LC‐MS/MS. Of these, 138 were annotated as hypothetical in the genome databases and the rest could be assigned to several metabolic and biosynthetic pathways, transport, and structural functions. Comparative analysis with a whole cell proteome study resulted in the validation of the expression of 173 additional proteins. Of these, 38 proteins previously reported in other stages were not found in the only large‐scale study of the total epimastigote stage proteome. A selected set of identified proteins was analyzed further to investigate gene copy number, sequence variation, transmembrane domains, and targeting signals. The genes were cloned and the proteins expressed with a c‐myc epitope tag in T. cruzi epimastigotes. Immunofluorescence microscopy revealed the localization of these proteins in different cellular compartments such as ER, acidocalcisome, mitochondrion, and putative cytoplasmic transport or delivery vesicles. The results demonstrate that the use of enriched subcellular fractions allows the detection of T. cruzi proteins that are undetected by whole cell proteomic methods.
Immunoproteomic analysis of the protective response obtained from vaccination with Candida albicans ecm33 cell wall mutant in mice
Authors: Martínez‐López Raquel , Nombela César , Diez‐Orejas Rosalía , Monteoliva Lucía , Gil Concha
Published: June 2008

Systemic candidiasis remains a major cause of disease and death, particularly among immunocompromised patients. The cell wall of Candida albicans defines the interface between host and pathogen and surface proteins are major elicitors of host immune responses during candidiasis. The C. albicans ecm33 mutant (RML2U) presents an altered cell wall, which entails an increase in the outermost protein layer. Vaccination of BALB/c mice with RML2U mutant protected them from a subsequent lethal infection with virulent strain SC5314 in a systemic candidiasis model. Using immunoproteomics (2‐DE followed by Immunoblotting) we detected 29 immunoreactive proteins specifically recognized by antibodies from vaccinated mice sera, six of which are described as immunogenic for the first time (Gnd1p, Cit1p, Rpl10Ep, Yst1p, Cys4p, Efb1p). Furthermore, identification of wild type and mutant cell surface proteome (surfome), confirmed us that the mutant surfome presented a larger number of proteins than the wild type. Interestingly, proteins exclusively identified in the mutant surfome (Met6p, Eft2p, Tkl1p, Rpl10Ep, Atp1p, Atp2p) were also detected as immunogenic, supporting the idea that their surface location enhances their immunoprotective capacity.
Matrix layer sample preparation: An improved MALDI‐MS peptide analysis method for proteomic studies
Authors: Garaguso Ignazio , Borlak Jürgen
Published: June 2008

The analytical performance of MALDI‐MS is highly influenced by sample preparation and the choice of matrix. Here we present an improved MALDI‐MS sample preparation method for peptide mass mapping and peptide analysis, based on the use of the 2,5‐dihydroxybenzoic acid matrix and prestructured sample supports, termed: matrix layer (ML). This sample preparation is easy to use and results in a rapid automated MALDI‐MS and MS/MS with high quality spectra acquisition. The between‐spot variation was investigated using standard peptides and statistical treatment of data confirmed the improvement gained with the ML method. Furthermore, the sample preparation method proved to be highly sensitive, in the lower‐attomole range for peptides, and we improved the performance of MALDI‐MS/MS for characterization of phosphopeptides as well. The method is versatile for the routine analysis of in‐gel tryptic digests thereby allowing for an improved protein sequence coverage. Furthermore, reliable protein identification can be achieved without the need of desalting sample preparation. We demonstrate the performance and the robustness of our method using commercially available reference proteins and automated MS and MS/MS analyses of in‐gel digests from lung tissue lysate proteins separated by 2‐DE.
Genetic or chemical protease inhibition causes significant changes in the Bacillus subtilis exoproteome
Authors: Westers Lidia , Westers Helga , Zanen Geeske , Antelmann Haike , Hecker Michael , Noone David , Devine Kevin M. , van Dijl Jan Maarten , Quax Wim J.
Published: June 2008

Bacillus subtilis is a prolific producer of enzymes and biopharmaceuticals. However, the susceptibility of heterologous proteins to degradation by (extracellular) proteases is a major limitation for use of B. subtilis as a protein cell factory. An increase in protein production levels has previously been achieved by using either protease‐deficient strains or addition of protease inhibitors to B. subtilis cultures. Notably, the effects of genetic and chemical inhibition of proteases have thus far not been compared in a systematic way. In the present studies, we therefore compared the exoproteomes of cells in which extracellular proteases were genetically or chemically inactivated. The results show substantial differences in the relative abundance of various extracellular proteins. Furthermore, a comparison of the effects of genetic and/or chemical protease inhibition on the stress response triggered by (over) production of secreted proteins showed that chemical protease inhibition provoked a genuine secretion stress response. From a physiological point of view, this suggests that the deletion of protease genes is a better way to prevent product degradation than the use of protease inhibitors. Importantly however, studies with human interleukin‐3 show that chemical protease inhibition can result in improved production of protease‐sensitive secreted proteins even in mutant strains lacking eight extracellular proteases.
Steric effect in alkylation reactions by N‐alkyl‐N‐nitrosoureas: a kinetic approach
Authors: Manso J. A. , Pérez‐Prior M. T. , García‐Santos M. P. , Calle E. , Casado J.
Published: June 2008

The alkylation reactions of 4‐(p‐nitrobenzyl)pyridine (NBP), a trap for alkylating agents with nucleophilic characteristics similar to DNA bases, by five N‐alkyl‐N‐nitrosoureas (methyl‐, ethyl‐, propyl‐, butyl‐, and allylnitrosourea) were investigated in 7:3 (v/v) water/dioxane medium in the 5.0–6.5 pH range. Decomposition of alkylnitrosoureas (ANU) gives rise to alkyldiazonium ions that yield NBP‐R adducts directly or through carbocations in certain instances. The NBP alkylation rate constants by these species were determined. The following sequence of alkylating potential was found: methyl‐ > ethyl‐ > allyl‐ > propyl‐ > butyl group. Application of Ingold–Taft correlation analysis to the kinetic results revealed that the NBP alkylation reactions occur mainly through steric control. The values of the molar absorption coefficients of the NBP‐R adducts also reveal the determinant influence of a steric effect in the formation of alkylation adducts. The kinetic results are consistent with the biological activity of ANU. Copyright © 2008 John Wiley & Sons, Ltd.
Kinetics and mechanism of oxidation of apple pectin by CrVI in aqueous acid medium
Authors: Bellú Sebastián E. , González Juan C. , García Silvia I. , Signorella Sandra R. , Sala Luis F.
Published: June 2008

Selective oxidation of galacturonic acid residues of apple pectin by CrVI affords CO2/HCO2H, oxidized pectin, and CrIII as final redox products. The reaction shows first‐order kinetics in [pectin], [CrVI], and [H+], at fixed ionic strength and temperature. Kinetic studies show that the redox reaction proceeds through a mechanism combining CrVI → CrIV → CrII and CrVI → CrIV → CrIII pathways. The mechanism is supported by the observation of free radicals, CrO (the formation of which implies involvement of CrII and CrIV) and CrV (formed in monoelectronic redox processes) as reaction intermediates. The reduction of CrIV and CrV by pectin was independently studied and found to occur more than 103 times faster than pectin + CrVI reaction, in acid medium. At pH 3–5, apple pectin + CrVI redox reaction is slow, oxo‐chromate(V)–pectin species stabilize and remain in solution during several hours. The present results show that these abundant and ubiquitous components of the cell walls of all land plants are able to reduce CrIV–VI or stabilize high‐valent chromium depending on pH. Copyright © 2008 John Wiley & Sons, Ltd.
Hydrogen bond‐directed self‐assembly of peripherally modified cyclotriphosphazenes with a homeotropic liquid crystalline phase
Authors: Xu Jianwei , Ling Toh Cher , He Chaobin
Published: June 2008

The synthesis and characterization of hydrogen‐bonded star‐shaped complexes consisting of stilbazolyloxy, azopyridyl, and Schiff base‐substituted cyclotriphosphazenes (3a, 3b, and 3c, respectively) and monoalkyloxy, bis(dodecyloxy), and tris(dodecyloxy)benzoic acids are reported. The thermal behaviors of complexes are studied by the means of differential scanning calorimetry, polarizing optical microscopy, and X‐ray diffractometry. Only 3a and 3b with monoalkyloxybenzoic acids show a homeotropic smectic A mesophase. The effect of azo and ethylene linkage of mesogenic groups in the cyclotriphosphazenes and the length of the flexible chain in monoalkyloxybenzoic acids on mesophase transition behaviors are investigated, revealing that the linkages in mesogenic groups governs the phase transition temperatures, and the length of flexible chain in proton donors plays an important role in controlling the magnitude of enthalpy and entropy of mesophase transitions in this supramolecular liquid crystal system. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 4691–4703, 2008
Thermally enhanced photoinduced in‐plane reorientation in photo‐cross‐linkable polymer liquid crystalline films and its application to linear polarizer
Authors: Kawatsuki Nobuhiro , Tsutsumi Ryoji , Hiraiwa Akie , Takatsuka Hirofumi , Sakai Takeya
Published: June 2008

Thermally enhanced photoinduced in‐plane molecular reorientation in new photo‐cross‐linkable polymer liquid crystalline (PPLC) films comprising 4‐[ω‐(4‐methoxycinnamoyloxy)alkyloxy]biphenyl side groups is explored using linearly polarized ultraviolet (LPUV) light exposure and subsequent annealing. The influence of the alkylene spacer length between the photo‐cross‐linkable group and the biphenyl mesogenic moiety is investigated. The straight‐line characteristics of the photoreactive mesogenic side group and the 4‐methoxycinnamoyl group play important roles in the high photoreactivity and the large thermally enhanced molecular reorientation, where the in‐plane order and the birefringence of the reoriented film are 0.61 and 0.18 are obtained. Finally, cooperative molecular reorientation of dichroic dyes doped in PPLC films is also achieved to fabricate a linear polarizer. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 4712–4718, 2008
Copolymerization of ethylene with cyclopentene or 2‐butene with half titanocenes‐based catalysts
Authors: Napoli Mariagrazia , Mariconda Annaluisa , Immediata Ivano , Longo Pasquale
Published: June 2008

Half titanocenes (CpCH2CH2O)TiCl2 (1), (CpCH2CH2OCH3)TiCl3 (2), and CpTiCl3 (3), activated by methylaluminoxane (MAO) were tested in copolymerization of ethylene with internal olefins such as cyclopentene. All the catalysts were able to give incorporation of cyclopentene in polyethylene matrix. 13C NMR analysis of obtained copolymers showed that the catalytic systems have low regiospecificity. In fact, in ethylene–cyclopentene copolymers, cyclic olefin inserts with both 1,2 and 1,3‐enchainment. X‐ray powder diffraction analysis of these copolymers confirmed that 1,2 inserted cyclopentene units are excluded from crystalline phase, whereas 1,3‐cyclopentene units are included, giving rise to expansion of unit cell of crystalline polyethylene. Titanium‐based catalysts were investigated also in the copolymerization of ethylene with E and Z‐2‐butene. Only complex (1) was able to give copolymers and 13C NMR analysis of products showed 2‐3, 1‐3, and 1‐2 insertion of 2‐butene. Differential scanning calorimetry analysis displayed that ethylene–cyclopentene, as well as ethylene‐2‐butene, copolymers are crystalline and their melting point decreases by increasing the comonomer content. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 4725–4733, 2008
Preparation of polysulfone‐g‐poly(N‐isopropylacrylamide) graft copolymers through atom transfer radical polymerization and formation of temperature‐responsive nanoparticles
Authors: Liu Ying‐Ling , Lin Guo‐Chain , Wu Chuan‐Shao
Published: June 2008

Polysulfone‐g‐poly(N‐isopropylacrylamide) (PSf‐g‐PNIPAAm) graft copolymers were prepared from atom transfer radical polymerization of NIPAAm using chloromethylated PSf as a macro‐initiator. The chain lengths of PNIPAAm of the graft copolymers were controllable with polymerization reaction time. The chemical structures of the graft copolymers were characterized with FTIR, NMR, and elemental analysis and their amphiphilic characteristics were examined and discussed. The PSf‐g‐PNIPAAm graft copolymers and the nanoparticles made from the graft copolymers exhibited repeatable temperature‐responsive properties in heating–cooling cycles. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 4756–4765, 2008
Grafting of polyamide 6 by the anionic polymerization of ε‐caprolactam from an isocyanate bearing polystyrene backbone
Authors: Zhang Cai‐Liang , Feng Lian‐Fang , Hoppe Sandrine , Hu Guo‐Hua
Published: June 2008

The grafting of polyamide 6 (PA6) onto polystyrene (PS) can rely on the use of a copolymer of styrene (St) and 3‐isopropenyl‐α, α‐dimethylbenzene isocyanate (TMI), PS‐co‐TMI, to activate the polymerization of ε‐caprolactam (CL) in the presence of sodium ε‐caprolactam (NaCL) as an anionic catalyst. This article is aimed at answering the following key questions. First, do all the isocyanate moieties of the PS‐co‐TMI participate in the activation of the polymerization of CL? Second, what are the composition of the resulting polymer product and the structure of the resulting graft copolymer? The results show that the isocyanate moieties had all participated in the activation of the polymerization, implying that each isocyanate moiety has led to the formation of a PA6 graft. The as‐polymerized product was composed of a pure PS‐g‐PA6 graft copolymer, homo‐PA6, and unreacted CL. Moreover, when the composition of a PS‐co‐TMI/CL/NaCL system was fixed, the mass ratio between the PA6 grafts and PS backbone of the pure PS‐g‐PA6 graft copolymer was almost a constant and was almost independent of its molar mass. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 4766–4776, 2008
Cationic polymerizations of 2‐alkyloxazolines catalyzed by bismuth salts
Authors: Buzin Pavel , Schwarz Gert , Kricheldorf Hans R.
Published: June 2008

Acidic bismuth salts, such as BiCl3, BiBr3, BiJ3, and Bi‐triflate catalyzed the ring‐opening polymerization of 2‐methoxazoline (MOZ) in bulk at 100 °C, whereas less acidic salts such as Bi2O3 or Bi(III)acetate did not. Bi‐triflate‐catalyzed polymerizations of 2‐ethyloxazoline (EtOZ) were performed with variation of the monomer–catalyst ratio (M/C). It was found that the molecular weights were independent of the M/C ratio. The formation of cationic chain ends and the absence of cycles was proven by reactions of virgin polymerization products with N,N‐dimethyl‐4‐aminopyridine or triphenylphosphine. The resulting polymers having modified cationic chain ends were characterized by 1H NMR spectroscopy and MALDI‐TOF mass spectrometry. The polymerization mechanism including chain‐transfer reactions is discussed. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 4777–4784, 2008
Initiator effect on the cationic ring‐opening copolymerization of 2‐ethyl‐2‐oxazoline and 2‐phenyl‐2‐oxazoline
Authors: Fijten Martin W. M. , Hoogenboom Richard , Schubert Ulrich S.
Published: June 2008

The aim of this research was to study the effect of the initiator on the resulting monomer distribution for the cationic ring‐opening copolymerization of 2‐ethyl‐2‐oxazoline (EtOx) and 2‐phenyl‐2‐oxazoline (PhOx). At first, kinetic studies were performed for the homopolymerizations of both monomers at 160 °C under microwave irradiation using four initiators. These initiators have the same benzyl‐initiating group but different leaving groups, Cl−, Br−, I−, and OTs−. The basicity of the leaving group affects the ratio of covalent and cationic propagating species and, thus, the polymerization rate. The observed differences in polymerization rates could be correlated to the concentration of cationic species in the polymerization mixture as determined by 1H NMR spectroscopy. In a next‐step, polymerization kinetics were determined for the copolymerizations of EtOx and PhOx with these four initiators. The reactivity ratios for these copolymerizations were calculated from the polymerization rates obtained for the copolymerizations. This approach allows more accurate determination of the copolymerization parameters compared to conventional methods using the composition of single polymers. When benzyl chloride (BCl) was used as an initiator, no copolymers could be obtained because its reactivity is too low for the polymerization of PhOx. With decreasing basicity of the used counterions (Br− > I− > OTs−), the reactivity ratios gradually changed from rEtOx = 10.1 and rPhOx = 0.30 to rEtOx = 7.9 and rPhOx = 0.18. However, the large difference in reactivity ratios will lead to the formation of quasi‐diblock copolymers in all cases. In conclusion, the used initiator does influence the monomer distribution in the copolymers, but for the investigated system the differences were so small that no difference in the resulting polymer properties is expected. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 4804–4816, 2008
Pathologic stage T2a and T2b prostate cancer in the recent prostate‐specific antigen era: Implications for unilateral ablative therapy
Authors: Polascik Thomas J. , Mayes Janice M. , Sun Leon , Madden John F. , Moul Judd W. , Mouraviev Vladimir
Published: June 2008

BACKGROUND

Early detection of small volume prostate cancer (PCa) has led to the concept of focal therapy to treat in an organ‐sparing manner. We evaluated trends in pathologic staging among patients with localized PCa undergoing radical prostatectomy (RP), defining the frequency of unilateral cancers during 1988–1995, 1996–2000 and 2001–2006.

METHODS

Data were abstracted from the Duke Prostate Cancer Outcome database selecting 3,676 men with available pathology treated with RP. Based on surgical pathology, trends in as pathological T (pT) stage, pathological Gleason Score (pGS), and percent tumor involvement (PTI) were evaluated.

RESULTS

pT2a increased from 2.8% of men undergoing RP in 1988–1995 to 13.0% during 2001–2006 (P  <  0.0005). PTI analysis shifted towards low volume disease, e.g. PTI ≤ 5% increased from 10% during 1988–1995, to 37% in 2001–2006 (P < 0.005). Of all pT2a disease throughout 1988–2006, an increase in proportion of pT2a tumors from 10% during 1988–1995 to 69.4% during 2001–2006 was identified. Over three eras, pT2a had minimal (65% had PTI ≤ 5%) or small volume (14% had PTI 5.01–10.00) disease, and 59% were low grade (pGS ≤ 6). Using a Cox Hazard model, pT2a versus pT2b disease, surgical margins, PTI, and PSA statistically contributed to PSA disease‐free survival in the contemporary era 2001–2006.

CONCLUSIONS

The increasing prevalence of unilateral pT2a/T2b PCa characterizes a growing proportion of men recently electing RP. These tumors are associated with lower PTI, pGS ≤ 7, and demonstrated better PSA‐free survival in the 2001–2006 era. These low risk pathologic characteristics may allow for unilateral focal therapy in carefully selected patients. Prostate 68: 1380–1386, 2008. © 2008 Wiley‐Liss, Inc.
GOLPH2 and MYO6: Putative prostate cancer markers localized to the Golgi apparatus
Authors: Wei Shuanzeng , Dunn Thomas A. , Isaacs William B. , De Marzo Angelo M. , Luo Jun
Published: June 2008

BACKGROUND

Malignant transformation is often accompanied by morphological and functional alterations in subcellular organelles. The Golgi apparatus is a subcellular structure primarily involved in modification and sorting of macromolecules for secretion and transport to other cellular destinations. Molecular alterations associated with the Golgi apparatus may take place during prostate carcinogenesis but such alterations have not been documented.

METHODS

To demonstrate that the Golgi apparatus undergoes alterations during prostate carcinogenesis, we examined the expression and localization of two candidate molecules, Golgi phosphoprotein 2 (GOLPH2) and myosin VI (MYO6), both overexpressed in prostate cancer as initially identified by expression microarray analysis.

RESULTS

Elevated GOLPH2 expression in prostate cancers was validated through real‐time RT‐PCR, Western blot, and tissue microarray analysis, and its Golgi localization in surgical prostate cancer tissues confirmed using two‐color immunofluorescence. In addition, distinctive juxtanuclear MYO6 staining pattern consistent with Golgi localization was observed in surgical prostate cancer tissues. Two‐color immunofluorescence revealed intensive Golgi‐specific staining for both GOLPH2 and myosin VI in prostate cancer cells but not in the adjacent normal prostate epithelium.

CONCLUSIONS

We show that the Golgi apparatus in prostate cancer cells differs from the normal Golgi by elevated levels of two molecules, GOLPH2 and MYO6. These results for the first time demonstrated consistent cancer cell‐specific alterations in the molecular composition of the Golgi apparatus. Such alterations can be explored for discovery of novel prostate cancer biomarkers through targeted organellar approaches. Prostate 68: 1387–1395, 2008. © 2008 Wiley‐Liss, Inc.