bluuebunny/crossref_metadata_2025 huggingface dataset:
CE‐MS and related techniques as a valuable tool in tumor biomarkers research
Authors: Simionato Ana Valéria Colnaghi , Carrilho Emanuel , Maggi Tavares Marina Franco
Published: March 2010

Cancer has been a disease of great concern because it is the second main cause of death in the world. Cures for most cancer pathologies have not yet been found, and an accurate and early diagnosis is essential for successful treatment. Therefore, research on tumor biomarkers has noticeably increased in recent years. The determination of such biomolecules, together with the routinely used laboratory exams for cancer diagnosis, would constitute a more reliable approach, known as systems biology. The “omics” era has corroborated in such investigations since the development of new technologies has arisen along with it. One of the techniques applied to the investigation of tumor biomarkers is CE, and the increasing applications of CE‐MS in this field are also observed. This review covers the published literature on tumor biomarker investigations by CE‐MS and related techniques, mostly within the last decade, but not limited to it. For didactic reasons this review is divided into the tumor biomarkers chemical classes, namely, proteins and related molecules, DNA adducts and modified nucleosides.
The selective determination of sulfates, sulfonates and phosphates in urine by CE‐MS
Authors: Bunz Svenja‐Catharina , Weinmann Wolfgang , Neusüß Christian
Published: March 2010

Metabolite identification and metabolite profiling are of major importance in the pharmaceutical and clinical context. However, highly polar and ionic substances are rarely included as analytical tools are missing. In this study, we present a new method for the determination of urinary sulfates, sulfonates, phosphates and other anions of strong acids. The method comprises a CE separation using an acidic BGE (pH≤2) and anodic detection by MS via negative ESI. In this way, only sulfates and sulfonates are detected in the first part of the electropherogram, followed by phosphates and potentially highly acidic carboxylates. The selectivity for sulfur‐containing species is proved using extracted ion electropherograms based on certain isotopic ratios. Ethyl sulfate can be determined by this method and, thus, CE‐MS can be used for determination of this alcohol consumption marker. An SPE method was developed for the extraction of ethyl sulfate and other organic anions. Several additional compounds can be identified based on the accurate mass determined by the TOF MS in conjunction with databases. However, numerous detected compounds have not been reported in urinary metabolite databases so far. Thus, it is demonstrated that the presented method is complementary to the existing methods for metabolite characterization in urine.
Repair of DNA interstrand cross‐links during S phase of the mammalian cell cycle
Authors: Legerski Randy J.
Published: March 2010

DNA interstrand cross‐linking (ICL) agents are widely used in anticancer chemotherapy regimens, yet our understanding of the DNA repair mechanisms by which these lesions are removed from the genome remains incomplete. This is at least in part due to the enormously complicated nature and variety of the biochemical pathways that operate on these complex lesions. In this review, we have focused specifically on the S‐phase pathway of ICL repair in mammalian cells, which appears to be the major mechanism by which these lesions are removed in cycling cells. The various stages and components of this pathway are discussed, and a putative molecular model is presented. In addition, we propose an explanation as to how this pathway can lead to the observed high levels of sister chromatid exchanges known to be induced by ICLs. Environ. Mol. Mutagen., 2010. © 2010 Wiley‐Liss, Inc.
Mammalian nucleotide excision repair proteins and interstrand crosslink repair
Authors: Wood Richard D.
Published: March 2010

Although various schemes for interstrand crosslink (ICL) repair incorporate DNA recombination, replication, and double‐strand break intermediate steps, action of the nucleotide excision repair (NER) system or some variation of it is a common feature of most models. In the bacterium Escherichia coli, the NER enzyme UvrABC can incise on either side of an ICL to unhook the crosslink, and can proceed via a subsequent recombination step. The relevance of NER to ICL repair in mammalian cells has been challenged. Of all NER mutants, it is clear that ERCC1 and XPF‐defective cells show the most pronounced sensitivities to ICL‐inducing agents, and defects in ICL repair. However, there is good evidence that cells defective in NER proteins including XPA and XPG are also more sensitive than normal to ICL‐inducing agents. These results are summarized here, together with evidence for defective crosslink removal in NER‐defective cells. Studies of incision at sites of ICL by cell extracts and purified proteins have been done, but these studies are not all consistent with one another and further research is required. Environ. Mol. Mutagen., 2010. © 2010 Wiley‐Liss, Inc.
What's in a name? Brain activity reveals categorization processes differ across languages
Authors: Liu Chao , Tardif Twila , Mai Xiaoqin , Gehring William J. , Simms Nina , Luo Yue‐Jia
Published: March 2010

The linguistic relativity hypothesis proposes that speakers of different languages perceive and conceptualize the world differently, but do their brains reflect these differences? In English, most nouns do not provide linguistic clues to their categories, whereas most Mandarin Chinese nouns provide explicit category information, either morphologically (e.g., the morpheme “vehicle” che1 in the noun “train” huo3che1 ) or orthographically (e.g., the radical “bug” chong2 in the character for the noun “butterfly” hu2die2 ). When asked to judge the membership of atypical (e.g., train) vs. typical (e.g., car) pictorial exemplars of a category (e.g., vehicle), English speakers (N = 26) showed larger N300 and N400 event‐related potential (ERP) component differences, whereas Mandarin speakers (N = 27) showed no such differences. Further investigation with Mandarin speakers only (N = 22) found that it was the morphologically transparent items that did not show a typicality effect, whereas orthographically transparent items elicited moderate N300 and N400 effects. In a follow‐up study with English speakers only (N = 25), morphologically transparent items also showed different patterns of N300 and N400 activation than nontransparent items even for English speakers. Together, these results demonstrate that even for pictorial stimuli, how and whether category information is embedded in object names affects the extent to which typicality is used in category judgments, as shown in N300 and N400 responses. Hum Brain Mapp, 2010. © 2010 Wiley‐Liss, Inc.
Synthesis, aggregation properties, and antiprotozoal activity of heterocyclic heterogemini surfactants
Authors: Lukáč M. , Timko L. , Mrva M. , Ondriska F. , Karlovská J. , Valentová J. , Lacko I.
Published: March 2010

A series of four heterogemini surfactants have been synthesized: 2‐decyl [dodecyl(dimethyl)ammonio]ethyl phosphate, decyl 2‐(1‐dodecylpyrrolidinio‐1‐yl)ethyl phosphate, decyl 2‐(1‐dodecylpiperidinio‐1‐yl)ethyl phosphate, and decyl 2‐(1‐dodecylmorpholinio‐1‐yl)ethyl phosphate. Antiprotozoal activity of prepared compounds against Acanthamoeba lugdunensis was investigated. Decyl 2‐(1‐dodecylpyrrolidinio‐1‐yl)ethyl phosphate exhibited the best trophocidal activity. The activities of heterogemini surfactants were compared with their aggregation properties. © 2010 Wiley Periodicals, Inc. 21:203–209, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20587
A concise synthesis of sex pheromone of mediterranean fruit fly, Ceratitis capitata via lithiated carbanion derived from enephosphoramide
Authors: Krzysztof Olszewski Tomasz , Grison Claude
Published: March 2010

A novel and versatile synthetic approach to the preparation of (E)‐non‐6‐en‐1‐ol, a sex pheromone of the Mediterranean fruit fly, Ceratitis capitata, is presented. This pheromone can be viewed as potential active component for lures designed to control and eradication of Mediterranean fruit fly. The described protocol is a six‐step reaction sequence producing the desired compound with 28% overall yield from commercially available and inexpensive starting material and total E stereoselectivity of the double bond present in final structure. The key to the success of the presented strategy is application of lithiated α‐allylphosphoramido carbanions and their reaction with halogenated acetals. © 2010 Wiley Periodicals, Inc. 21:139–147, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20588
An impact evaluation of the Safe Motherhood Program in China
Authors: Feng Xing Lin , Shi Guang , Wang Yan , Xu Ling , Luo Hao , Shen Juan , Yin Hui , Guo Yan
Published: March 2010

Using 11 years of county‐level panel data, fixed effect models are estimated to evaluate the impact of the Safe Motherhood (SM) Program in China. Propensity score matching is used to select comparable factual and counterfactual counties. Out of 2013 counties in China, 283 are selected for the treatment group and 1051 for the control group. The results support the causal relationship between the program and its targeted outcomes and the partial effects increases as years of exposure in the program: 7 years' treatment of the program increases hospital delivery rate by 3.992 per 100 live births and decreases Maternal mortality ratio (MMR) due to hemorrhage by 10.229 per 100 000 live births. Further modeling supports the conclusion that the program reduces MMR by enhancing MCH care. With an average annual incremental unit cost for the program of about 318.0 thousand RMB (39.8 thousand USD) per county, we conclude that the SM Program is effective in reducing MMR through the enhancement of hospital delivery. Copyright © 2010 John Wiley & Sons, Ltd.
Utility of TL‐201 SPECT in clarifying false‐positive FDG‐PET findings due to osteoradionecrosis in head and neck cancer
Authors: Wang Chih‐Hsiu , Liang Ji‐An , Ding Hueisch‐Jy , Yang Shih‐Neng , Yen Kuo‐Yang , Sun Shung‐Shung , Kao Chia‐Hung
Published: March 2010

Background

This study aimed to determine whether Tl‐201 single photon emission CT (SPECT) is potentially useful in differentiating false‐positive fluorodeoxyglucose positron emission tomography (FDG‐PET) findings caused by osteoradionecrosis (ORN) from recurrent head and neck cancer after radiotherapy.

Methods

Five patients were recruited. Dual‐phase FDG‐PET and dual‐phase Tl‐201 SPECT were performed for each patient.

Results

All 5 patients proved to have ORN without recurrent cancer. By visual interpretation, the results were 4 positive versus 1 negative for PET, and 4 negative versus 1 positive for Tl‐201 SPECT. The Tl‐201 SPECT clarified 3 of the 4 false‐positive PETs to be ORN. Dual‐phase semiquantitative studies showed decreased standardized uptake value (SUV) over time in 3 of the 4 false‐positive PETs and decreased lesion/background ratio over time in the false‐positive Tl‐201 SPECT.

Conclusion

The Tl‐201 SPECT may help clarify suspected false‐positive FDG uptake caused by ORN. Dual‐phase FDG‐PET and dual‐phase Tl‐201 SPECT may also have some value. © 2010 Wiley Periodicals, Inc. Head Neck, 2010
Diagnostic accuracy of fine‐needle aspiration cytology in Warthin tumors
Authors: Veder Laura L. , Kerrebijn Jeroen D.F. , Smedts Frank M. , den Bakker Michael A.
Published: March 2010

Background

Our aim was to evaluate the diagnostic accuracy of fine‐needle aspiration cytology (FNAC) for Warthin tumors of the parotid gland.

Methods

All cytologic diagnoses of Warthin tumor between 1990 and 2007 were correlated with available histology. In addition, our results were compared to current literature.

Results

In 310 cases, Warthin tumor was diagnosed by FNAC. In 133 cases, (43%) both cytology and histology were available. In 127 of these 133 cases (95.5%), the diagnosis Warthin tumor was confirmed by histology. In 4 cases (3%), a benign lesion was diagnosed and 2 (1.5%) revealed a malignant lesion. On review, those cytologic diagnoses were not certain. In the literature, 11 missed malignancies (5.4%) in 202 cases were reported.

Conclusion

The diagnostic accuracy of FNAC for the diagnosis of Warthin tumor is high and the percentage of missed malignant tumors is very low. Our results imply that a cytologic diagnosis of Warthin tumor may justify conservative treatment. © 2010 Wiley Periodicals, Inc. Head Neck, 2010
Effective work‐life balance support for various household structures
Authors: ten Brummelhuis Lieke L. , van der Lippe Tanja
Published: March 2010

Today's workforce encompasses a wide variety of employees with specific needs and resources when it comes to balancing work and life roles. Our study explores whether various types of work‐life balance support measures improve employee helping behavior and performance among single employees, employees with a partner, and employees with a partner and children. Using a sample of 482 employees at 24 organizations, the results showed that the organization's work‐family culture improved work performance among parents but reduced performance among singles. Singles' work outcomes improved, however, when they had access to flexible work arrangements, whereas couples benefited from their supervisors' social support. The results stress the importance of the employee's household structure when considering appropriate support for balancing work and life roles. © 2010 Wiley Periodicals, Inc.
Human resource management practices affecting unit managers in franchise networks
Authors: Castrogiovanni Gary J. , Kidwell Roland E.
Published: March 2010

Franchising is an important context in studying entrepreneurship and a growing area of business activity worldwide. To date, various studies have considered the strategic implications of decisions to retain firm ownership of particular units or to franchise them. Little attention, however, has focused on the differences between employee or franchisee managers of those units. We address this gap in the literature by offering a perspective on human resource management (HRM) and franchising that considers those differences, thus providing a bridge between the HRM and franchising fields of inquiry. © 2010 Wiley Periodicals, Inc.
Linking HR formality with employee job quality: The role of firm and workplace size
Authors: Storey David J. , Saridakis George , Sen‐Gupta Sukanya , Edwards Paul K. , Blackburn Robert A.
Published: March 2010

The process of managing a small firm differs from managing a large firm, because small firms face distinct forms of risk and organize their human resources differently, often informally (Kotey & Slade, 2005; Storey, 2002). This paper introduces and tests a new variable, self‐reported job quality (SRJQ), as a key link in the causal chain between HR practices and outcomes. In comparing small firms with large ones, we present three key findings: (1) employee reports of job quality are highest in small firms and decrease as firm size increases; (2) in workplaces owned by large firms, job quality is highest in the smallest workplaces; and (3) workers in small workplaces owned by large firms report lower job quality than workers in comparable sized workplaces owned by small firms. Our findings are partially explained by how formally HR practices are implemented. We show that formality increases with firm size and workplace size. Importantly, evidence suggests that employing an HR professional (a key indicator of HR formality) lowers SRJQ in single‐site SMEs. Implications for small business owners, HR professionals in large and small firms, and policy makers are discussed. © 2010 Wiley Periodicals, Inc.
Historical discharge measurements on the Middle Mississippi River, USA: no basis for ‘changing history’
Authors: Pinter Nicholas
Published: March 2010

This study tests the hypothesis that historical float‐based discharge measurements on the Mississippi River systematically over‐stated actual flood flows by 10% to > 30% relative to measurements using current meters. This assertion has been repeated over the past 25 years and recently has been used to adjust historical discharges used for flood‐frequency analysis. This study tests the hypothesis above using 2150 historical discharge measurements digitized from the three principal gauging stations on the Middle Mississippi River (MMR): data that include 626 float‐based discharges and 1516 meter‐based discharges, including 122 paired measurements. Multiple comparative tests show that the hypothesis above cannot be supported; if anything, the float‐based measurements slightly underestimate flows (not over‐estimate) over a broad range of discharges up to large floods. In response to the purported data bias above (‘changing history’; Dieckmann RJ, Dyhouse GR. 1998. Changing history at St. Louis—adjusting historic flows for frequency analysis. First Federal Inter‐Agency Hydrologic Modeling Conference, April 20–22, 1998. Las Vegas, NV; 4·31–4·36), historical flood discharges on the MMR have been modified, most by 10–20% and several by > 30%. These altered discharges are now being promulgated, in particular, through the Upper Mississippi River System Flow Frequency Study (UMRSFFS). New flow frequencies, flood profiles, and new flood maps from the UMRSFFS may significantly underestimate the actual flood hazard on the MMR if the original hydrologic data have been erroneously altered on the basis of an assumption of data bias. Copyright © 2010 John Wiley & Sons, Ltd.
Aquatic hazard assessment for pharmaceuticals, personal care products, and endocrine-disrupting compounds from biosolids-amended land
Authors: Langdon KA , Warne MStJ , Kookana RS
Published: March 2010

Reuse of biosolids on agricultural land is a common practice. Following the application of biosolids to land, contaminants in the biosolids have the potential to migrate offsite via surface runoff and/or leaching and pose a hazard to aquatic ecosystems. The aim of this screening-level assessment study was to determine the relative hazard posed to aquatic ecosystems by pharmaceuticals, personal care products, and endocrine-disrupting compounds (EDCs) that have been detected and quantified in biosolids. This involved estimating maximum possible runoff water concentrations of compounds, using an equilibrium partitioning approach and then comparing these with the lowest available aquatic toxicity data, using the hazard quotient (HQ) approach. A total of 45 pharmaceuticals, personal care products, and EDCs have been detected in biosolids. Ten of these compounds (tonalide, galaxolide, 17β-estradiol, 17α-ethinylestradiol, ciprofloxacin, doxycycline, norfloxacin, ofloxacin, triclosan, and triclocarban) posed a high (HQ >1.0) hazard to aquatic ecosystems relative to the other compounds. This hazard assessment indicated that further research into potential offsite migration and deleterious effects on aquatic ecosystems is warranted for the 10 organic contaminants identified, and possibly for chemicals with similar physicochemical and toxicological properties, in biosolids-amended soils. Because many antibiotic compounds (e.g., ciprofloxacin, norfloxacin, and ofloxacin) have ionic properties, the methods used may have overestimated their predicted aqueous concentrations and hazard. Further research that includes site-specific variables, e.g., dilution factors in waterways, rain intensity, slope of land, degradation, and the use of management strategies such as buffer zones, is likely to decrease the hazard posed by these high hazard compounds. Integr Environ Assess Manag 2010;6:663–676. © 2010 SETAC
Mössbauer spectroscopic studies of the six‐coordinate heme—nitric oxide complex of iron(III) octaethylporphyrin N‐methylimidazole, the first model of the nitrophorin—no complexes
Authors: Schünemann Volker , Benda Rüdiger , Trautwein Alfred X. , Walker F. Ann
Published: March 2010

The NO, N‐methylimidazole complex of isotopically enriched octaethylporphyrinatoiron(III) chloride, [OEP57Fe(NO)(N‐MeIm)+Cl− has been prepared in dimethylacetamide solution and studied by low‐temperature Mössbauer spectroscopy in the presence and absence of a magnetic field. This complex is a model for the Fe(III)‐NO complexes of the nitrophorins of the blood‐sucking insect, Rhodnius prolixus, where NO is released from the histidine‐coordinated ferrihemin center of each of the proteins upon the insect's injection of the saliva into the victim. The [OEPFe(NO)(N‐MeIm)]+Cl− complex is EPR silent and behaves as a diamagnetic species, with quadrupole splitting ΔEQ = 1.64 mm s−1, asymmetry parameter η = 0.4, isomer shift δ = 0.02 mm s−1, and linewidth Γ= 0.3 mm s−1. Two electron configurations, Fe(III)‐NO (low‐spin d5, strongly antiferromagnetically coupled to NO), or Fe(II)‐NO+ (low‐spin d6, purely diamagnetic), are possible. Which is the actual configuration cannot be determined until detailed molecular calculations are carried out. The low‐spin OEPFe(III)‐bis‐N‐methylimidazole complex also present in this sample has EPR g‐values, quadrupole splitting, isomer shift, and hyperfine splittings typical of rhombic low‐spin ferriheme centers.
Accuracy of high-resolution in vivo micro magnetic resonance imaging for measurements of microstructural and mechanical properties of human distal tibial bone
Authors: Liu X Sherry , Zhang X Henry , Rajapakse Chamith S , Wald Michael J , Magland Jeremy , Sekhon Kiranjit K , Adam Mark F , Sajda Paul , Wehrli Felix W , Guo X Edward
Published: March 2010

Micro magnetic resonance imaging (µMRI) is an in vivo imaging method that permits 3D quantification of cortical and trabecular bone microstructure. µMR images can also be used for building microstructural finite element (µFE) models to assess bone stiffness, which highly correlates with bone's resistance to fractures. In order for µMRI-based microstructural and µFE analyses to become standard clinical tools for assessing bone quality, validation with a current gold standard, namely, high-resolution micro computed tomography (µCT), is required. Microstructural measurements of 25 human cadaveric distal tibias were performed for the registered µMR and µCT images, respectively. Next, whole bone stiffness, trabecular bone stiffness, and elastic moduli of cubic subvolumes of trabecular bone in both µMR and µCT images were determined by voxel-based µFE analysis. The bone volume fraction (BV/TV), trabecular number (Tb.N*), trabecular spacing (Tb.Sp*), cortical thickness (Ct.Th), and structure model index (SMI) based on µMRI showed strong correlations with µCT measurements (r2 = 0.67 to 0.97), and bone surface-to-volume ratio (BS/BV), connectivity density (Conn.D), and degree of anisotropy (DA) had significant but moderate correlations (r2 = 0.33 to 0.51). Each of these measurements also contributed to one or many of the µFE-predicted mechanical properties. However, model-independent trabecular thickness (Tb.Th*) based on µMRI had no correlation with the µCT measurement and did not contribute to any mechanical measurement. Furthermore, the whole bone and trabecular bone stiffness based on µMRI were highly correlated with those of µCT images (r2 = 0.86 and 0.96), suggesting that µMRI-based µFE analyses can directly and accurately quantify whole bone mechanical competence. In contrast, the elastic moduli of the µMRI trabecular bone subvolume had significant but only moderate correlations with their gold standards (r2 = 0.40 to 0.58). We conclude that most microstructural and mechanical properties of the distal tibia can be derived efficiently from µMR images and can provide additional information regarding bone quality. © 2010 American Society for Bone and Mineral Research.
Sex-specific regulation of body size and bone slenderness by the acid labile subunit
Authors: Courtland Hayden-William , DeMambro Victoria , Maynard Jane , Sun Hui , Elis Sebastien , Rosen Clifford , Yakar Shoshana
Published: March 2010

Insulin-like growth factor 1 (IGF-1) is a crucial mediator of body size and bone mass during growth and development. In serum, IGF-1 is stabilized by several IGF-1-binding proteins (IGFBPs) and the acid labile subunit (ALS). Previous research using ALS knockout (ALSKO) mice indicated a growth retardation phenotype, and clinical reports of humans have indicated short stature and low bone mineral density (BMD) in patients with ALS deficiency. To determine the temporal and sex-specific effects of ALS deficiency on body size and skeletal development during growth, we characterized control and ALSKO mice from 4 to 16 weeks of age. We found that female ALSKO mice had an earlier-onset reduction in body size (4 weeks) but that both female and male ALSKO mice were consistently smaller than control mice. Interestingly, skeletal analyses at multiple ages showed increased slenderness of ALSKO femurs that was more severe in females than in males. Both male and female ALSKO mice appeared to compensate for their more slender bones through increased bone formation on their endosteal surfaces during growth, but ALSKO females had increased endosteal bone formation compared with ALSKO males. This study revealed age- and sex-specific dependencies of body size and bone size on the ALS. These findings may explain the heterogeneity in growth and BMD measurements reported in human ALS-deficient patients. © 2010 American Society for Bone and Mineral Research.
Peak bone mass from longitudinal data: Implications for the prevalence, pathophysiology, and diagnosis of osteoporosis
Authors: Berger Claudie , Goltzman David , Langsetmo Lisa , Joseph Lawrence , Jackson Stuart , Kreiger Nancy , Tenenhouse Alan , Davison K Shawn , Josse Robert G , Prior Jerilynn C , Hanley David A ,   and the CaMos Research Group
Published: March 2010

We estimated peak bone mass (PBM) in 615 women and 527 men aged 16 to 40 years using longitudinal data from the Canadian Multicentre Osteoporosis Study (CaMos). Individual rates of change were averaged to find the mean rate of change for each baseline age. The age range for PBM was defined as the period during which bone mineral density (BMD) was stable. PBM was estimated via hierarchical models, weighted according to 2006 Canadian Census data. Lumbar spine PBM (1.046 ± 0.123 g/cm2) occurred at ages 33 to 40 years in women and at 19 to 33 years in men (1.066 ± 0.129 g/cm2). Total hip PBM (0.981 ± 0.122 g/cm2) occurred at ages 16 to 19 years in women and 19 to 21 years in men (1.093 ± 0.169 g/cm2). Analysis of Canadian geographic variation revealed that the levels of PBM and of mean BMD in those over age 65 sometimes were discordant, suggesting that PBM and subsequent rates of bone loss may be subject to different genetic and/or environmental influences. Based on our longitudinally estimated PBM values, the estimated Canadian prevalences of osteoporosis (T-score < –2.5) were 12.0% (L1–L4) and 9.1% (total hip) in women aged 50 years and older and 2.9% (L1–L4) and 0.9% (total hip) in men aged 50 years and older. These were higher than prevalences using cross-sectional PBM data. In summary, we found that the age at which PBM is achieved varies by sex and skeletal site, and different reference values for PBM lead to different estimates of the prevalence of osteoporosis. Furthermore, lack of concordance of PBM and BMD over age 65 suggests different determinants of PBM and subsequent bone loss. © 2010 American Society for Bone and Mineral Research
Increased immortalization‐upregulated protein 2 (IMUP‐2) by hypoxia induces apoptosis of the trophoblast and pre‐eclampsia
Authors: Jeon Su Yeon , Lee Hyun‐Jung , Park Ji Myeong , Jung Hyun Min , Yoo Jung Ki , Lee Hey‐Jin , Lee Jong‐Sung , CHA Dong‐Hyun , Kim Jin Kyeoung , Kim Gi Jin
Published: March 2010

In regulation of the developmental process, the balance between cellular proliferation and cell death is critical. Placental development tightly controls this mechanism, and increased apoptosis of placental trophoblasts can cause a variety of gynecological diseases. Members of the immortalization‐upregulated protein (IMUP) family are nuclear proteins implicated in SV40‐mediated immortalization and cellular proliferation; however, the mechanisms by which their expression is regulated in placental development are still unknown. We compared IMUP‐2 expression in normal and pre‐eclamptic placental tissues and evaluated the function of IMUP‐2 in HTR‐8/SVneo trophoblast cells under hypoxic conditions. IMUP‐2 was expressed in syncytiotrophoblasts and syncytial knots of the placental villi. IMUP‐2 expression was significantly higher in preterm pre‐eclampsia patients than in patients who went to term (P < 0.001); however, we observed no differences in IMUP‐2 expression between normal term patients with and without pre‐eclampsia. Hypoxic conditions increased apoptosis of HTR8/SVneo trophoblast cells and induced IMUP‐2 expression. Also, apoptosis of HTR‐8/SVneo trophoblast cells was increased after IMUP‐2 gene transfection. These results suggest that IMUP‐2 expression is specifically elevated in preterm pre‐eclampsia and under hypoxic conditions, and that IMUP‐2 induces apoptosis of the trophoblast. Therefore, IMUP‐2 might have functional involvement in placental development and gynecological diseases such as pre‐eclampsia. J. Cell. Biochem. 110: 522–530, 2010. © 2010 Wiley‐Liss, Inc.
The Human IGF1R IRES likely operates through a Shine–Dalgarno‐like interaction with the G961 loop (E‐site) of the 18S rRNA and is kinetically modulated by a naturally polymorphic polyU loop
Authors: Meng Zheng , Jackson Nateka L. , Shcherbakov Oleg D. , Choi Hyoungsoo , Blume Scott W.
Published: March 2010

IGF1R is a proto‐oncogene with potent mitogenic and antiapoptotic activities, and its expression must be tightly regulated to maintain normal cellular and tissue homeostasis. We previously demonstrated that translation of the human IGF1R mRNA is controlled by an internal ribosome entry site (IRES), and delimited the core functional IRES to a 90‐nucleotide segment of the 5′‐untranslated region positioned immediately upstream of the initiation codon. Here we have analyzed the sequence elements that contribute to the function of the core IRES. The Stem2/Loop2 sequence of the IRES exhibits near‐perfect Watson–Crick complementarity to the G961 loop (helix 23b) of the 18S rRNA, which is positioned within the E‐site on the platform of the 40S ribosomal subunit. Mutations that disrupt this complementarity have a negative impact on regulatory protein binding and dramatically decrease IRES activity, suggesting that the IGF1R IRES may recruit the 40S ribosome by a eukaryotic equivalent of the Shine–Dalgarno (mRNA–rRNA base‐pairing) interaction. The homopolymeric Loop3 sequence of the IRES modulates accessibility and limits the rate of translation initiation mediated through the IRES. Two functionally distinct allelic forms of the Loop3 poly(U)‐tract are prevalent in the human population, and it is conceivable that germ‐line or somatic variations in this sequence could predispose individuals to development of malignancy, or provide a selectable growth advantage for tumor cells. J. Cell. Biochem. 110: 531–544, 2010. © 2010 Wiley‐Liss, Inc.
A novel intracellular isoform of VEGFR‐1 activates Src and promotes cell invasion in MDA‐MB‐231 breast cancer cells
Authors: Mezquita Belén , Mezquita Jovita , Pau Montserrat , Mezquita Cristóbal
Published: March 2010

Two types of VEGFR‐1 receptors have been characterized: a full‐length transmembrane receptor and a truncated extracellular soluble isoform (sVEGFR‐1). We report here the characterization, in normal and cancer cells, of a new family of intracellular isoforms of VEGFR‐1 resulting from alternative initiation of transcription in intronic sequences of the gene. While the classical isoforms of VEGFR‐1 were barely detectable in MDA‐MB‐231 breast cancer cells, one of the intracellular isoforms transcribed from intron 21 (i21VEGFR‐1) was the main isoform expressed in these cells. The new transcript encodes for a protein that contains only the phosphotransferase domain and the carboxyterminal tail of VEGFR‐1. Treatment of MDA‐MB‐231 cells with siRNA specific for the tyrosine domain of VEGFR‐1 suppressed the expression of i21VEGFR‐1, downregulated phosphorylation of Src at tyrosine 418, and reduced markedly the invasion capacity of these cells in vitro. Accordingly, overexpression of transfected i21VEGFR‐1 in MDA‐MB‐231 cells upregulated the active form of Src and increased invasiveness of MDA‐MB‐231 cells. The expression of i21VEGFR‐1 in MDA‐MB‐231 cells was inhibited by retinoic acid. Both, activation of Src and downregulation by retinoic acid, have been reported in other intracellular members of the Fms/Kit/PDGFR family of tyrosine kinases, particularly in the intracellular isoform of c‐kit, analogous structurally to i21VEGFR‐1 and frequently expressed in cancer cells. J. Cell. Biochem. 110: 732–742, 2010. © 2010 Wiley‐Liss, Inc.
Physiology of hibernation under the ice by turtles and frogs
Authors: Jackson Donald C. , Ultsch Gordon R.
Published: March 2010

Successful overwintering under ice by an air‐breathing vertebrate requires either effective aquatic respiration if dissolved O2is available or the capacity for prolonged anaerobic metabolism if O2supplies are limiting. Frogs can remain aerobic for many weeks when submerged at low temperature, even at water PO2as low as 30 mmHg, but are unable to survive even 1 week in anoxic water. Fuel reserves of hibernating frogs limit aerobic submergence, whereas acidosis may limit anoxic submergence. Freshwater turtles can also satisfy all or most of their O2needs in well‐aerated water at low temperature by aquatic respiration, but certain species, in particular painted and snapping turtles, can also survive for up to 4–5 months without O2. Key adaptations of the painted turtles, and presumably snapping turtles, include metabolic depression and the exploitation of the shell and other bones to buffer lactic acid. As in frogs, glycogen and glucose are the only fuel sources during anoxia, and stores do not seem to be limiting in the painted turtle. Significant differences in anoxia tolerance exist among chelonian species that can be attributed, at least in part, to the magnitude of metabolic depression, the effectiveness of lactic acid buffering, and the size of glycogen stores.J. Exp. Zool. 313A:311–327, 2010. © 2010 Wiley‐Liss, Inc.
Preparation and properties in vitro and in vivo of antitubercular pyrroles
Authors: Hearn Michael J. , Chen Michaeline F. , Terrot Marianne S. , Webster Eleanor R. , Cynamon Michael H.
Published: March 2010

magnified image

1‐Acylamino‐2,5‐dimethylpyrroles were prepared in the exploration of heterocyclic structures useful for their antitubercular activity. The pyrroles were conveniently formed from the reaction of aromatic acid hydrazides with hexane‐2,5‐dione in water or ethanol, without resorting to acid catalysis. In each case, the procedure provided a single pyrrole in pure form, and the product was identified without difficulty on the basis of highly characteristic spectrometric features. Some members of this class have significant activities against drug‐resistant tuberculosis in vitro and offer substantial protection in a rigorous mouse model of the disease. J. Heterocyclic Chem., (2010).
Decreased knee adduction moment does not guarantee decreased medial contact force during gait
Authors: Walter Jonathan P. , D'Lima Darryl D. , Colwell Clifford W. , Fregly Benjamin J.
Published: March 2010

Excessive contact force is believed to contribute to the development of medial compartment knee osteoarthritis. The external knee adduction moment (KAM) has been identified as a surrogate measure for medial contact force during gait, with an abnormally large peak value being linked to increased pain and rate of disease progression. This study used in vivo gait data collected from a subject with a force‐measuring knee implant to assess whether KAM decreases accurately predict corresponding decreases in medial contact force. Changes in both quantities generated via gait modification were analyzed statistically relative to the subject's normal gait. The two gait modifications were a “medial thrust” gait involving knee medialization during stance phase and a “walking pole” gait involving use of bilateral walking poles. Reductions in the first (largest) peak of the KAM (32–33%) did not correspond to reductions in the first peak of the medial contact force. In contrast, reductions in the second peak and angular impulse of the KAM (15–47%) corresponded to reductions in the second peak and impulse of the medial contact force (12–42%). Calculated reductions in both KAM peaks were highly sensitive to rotation of the shank reference frame about the superior–inferior axis of the shank. Both peaks of medial contact force were best predicted by a combination of peak values of the external KAM and peak absolute values of the external knee flexion moment (R2 = 0.93). Future studies that evaluate the effectiveness of gait modifications for offloading the medial compartment of the knee should consider the combined effect of these two knee moments. Published by Wiley Periodicals, Inc. J Orthop Res 28:1348–1354, 2010
Fast three‐dimensional chemical imaging by interferometric multiplex coherent anti‐Stokes Raman scattering microscopy
Authors: Sung Jiha , Chen Bi‐Chang , Lim Sang‐Hyun
Published: March 2010

We report significant improvements in both signal sensitivity and imaging speed of Fourier transform spectral interferometry coherent anti‐Stokes Raman scattering (FTSI‐CARS) microscopy. With a help of an apodization function in the signal retrieval process, background due to the spectral change of nonresonant signals is eliminated. We experimentally verify that the sensitivity of the improved method is nearly shot‐noise‐limited. The current maximum detection sensitivity is ∼10 mM of aqueous sulfate ions, which correspond to ∼106 oscillators in the microscopy focal volume. Operating the charge‐coupled device (CCD) in the crop mode increases the image acquisition speed by more than ten times. A vibrational hyperspectral image of a polymer sample with 100 × 100 pixel can be obtained within 3 s. With the improved sensitivity and speed, we also perform three‐dimensional volume imaging. Superior chemical selectivity is demonstrated with a mixture of two different oil droplets, which have identical vibrational peak positions but different relative peak ratios. Copyright © 2010 John Wiley & Sons, Ltd.
LAPTM4B‐35 is a novel prognostic factor of hepatocellular carcinoma
Authors: Yang Hua , Xiong Fuxia , Qi Ruizhao , Liu Zhenwen , Lin Ming , Rui Jingan , Su Jing , Zhou Rouli
Published: March 2010

Background

LAPTM4B‐35 is a 35‐kDa tetra‐transmembrane protein overexpressed in hepatocellular carcinoma (HCC) and promotes cell survival, proliferation, and tumorigenesis. However, the potential clinical implications of LAPTM4B‐35 in HCC are still unclear. This study is aimed to investigate the correlations between LAPTM4B‐35 expression and prognosis in patients with HCC.

Methods

Western blot and immunohistochemistry assays were used to determine the expression of LAPTM4B‐35 in HCCs and their paired noncancerous liver tissues from 65 patients. The correlations of LAPTM4B‐35 expression with clinicopathological parameters were assessed by Chi‐square test. Patient survival was determined by Kaplan–Meier method and log‐rank test. Cox regression was adopted for multivariate analysis of prognostic factors.

Results

LAPTM4B‐35 overexpression occurred in 76.9% of HCC tissues, while only in 4.6% of noncancerous liver tissues. Overexpression of LAPTM4B‐35 was significantly associated with TNM staging and invasive tumors. Patients with higher LAPTM4B‐35 expression had significantly poorer overall survival (OS) and disease‐free survival (DFS) (both P < 0.001). On multivariate analysis, elevated expression of LAPTM4B‐35 was found to be an independent prognostic factor for OS and DFS (P = 0.009, 0.043, respectively).

Conclusions

LAPTM4B‐35 overexpression is an independent prognostic factor for OS and DFS of HCC. J. Surg. Oncol. 2010; 101:363–369. © 2010 Wiley‐Liss, Inc.
Prediction and Experimental Characterization of the Molecular Architecture of FRP and ATRP Synthesized Polyacrylate Networks
Authors: Gonçalves Miguel A. D. , Dias Rolando C. S. , Costa Mário Rui P. F. N.
Published: March 2010

Summary: This work reports experimental and modeling studies concerning the conventional (FRP) and atom transfer radical polymerization (ATRP) of acrylate/diacrylate monomers. In the framework of a recently developed general approach, kinetic models including crosslinking reactions and branching by chain transfer to polymer are discussed for FRP and ATRP polymerization systems. Besides molecular weight distribution (MWD), fairly good predictions of the z‐average radius of gyration could be obtained for these non‐linear polymers. A set of experiments was performed at 1 L scale in a batch reactor using n‐butyl acrylate (BA) or methyl acrylate (MA) as monovinyl monomers and 1,6‐Hexanediol diacrylate (HDDA) or bisphenol A ethoxylate diacrylate (BEDA) as crosslinkers. In FRP experiments, AIBN was used as initiator and ATRP polymerizations were initiated by ethyl 2‐bromopropionate (EBrP) and mediated by CuBr using PMDETA (N,N,N′,N″,N″‐pentamethyldiethylenetriamine) as ligant. Polymerizations were carried out in solution at 60 °C with different dilutions using toluene and DMF as solvents. Products formed at different polymerization times were analyzed by SEC/RI/MALLS yielding average MW, MWD, z‐average radius of gyration and monomer conversion. Important differences in the molecular architecture of the synthesized FRP and ATRP highly branched polyacrylates have been identified. Comparisons of experimental results with predictions have put into evidence the important effect of intramolecular cyclizations at all dilutions, even with ATRP polymerizations.
High‐Yield Synthesis of Gold Microplates Using Amphiphilic Block Copolymers: Are Lyotropic Liquid Crystals Required?
Authors: Sakai Toshio , Alexandridis Paschalis
Published: March 2010

Summary: High‐yield synthesis of gold microplates is achieved through autoreduction of hydrogen tetrachloroaureate (III) hydrate (HAuCl4 · 3H2O) in aqueous solutions of poly(ethylene oxide)‐poly(propylene oxide)‐poly(ethylene oxide) block copolymer (Pluronic L64, EO13PO30EO13) at ambient conditions, in the absence of added energy, reductant, or other surfactants. The formation by the amphiphilic block copolymer of lyotropic liquid crystals (e.g., ordered cylindrical/hexagonal or lamellar phases) is not required for templating the formation of such microplates.
Silica Nanotube Reactors for Catalytic Polymerization of Styrene and Olefins
Authors: Han Joong Jin , Lee Sang Yool , Lee Sang Bok , Choi Kyu Yong
Published: March 2010

Summary: Silica nanotube reactor (SNTR) has been designed and used as a novel catalytic polymerization reactor device to synthesize syndiotactic polystyrene (sPS), and polyethylene with Cp*Ti(OCH3)3 and rac‐Et(indenyl)2ZrCl2 metallocene catalysts in conjunction with methylaluminoxane (MAO). The highly crystalline sPS molecules polymerized within the SNTR form nano‐scale polymeric fibrils of 30–50 nm in diameter that further intertwine to fill the nanopore. The polymer molecular weight of sPS has been found to increase significantly in the SNTR. A simplified mathematical reaction model for the SNTR suggests that hindered chain transfer reactions in the nanopores filled with rigid polymeric nanofibrils might have caused the extended polymer chain length. The morphological characteristics of polymeric nanofibrils and the effect of SNTR's geometric confinement on the polymer properties are also discussed. It is also demonstrated that the liberated SNTR can be a novel ‘See‐Through’ tool for visual observation when it is analyzed by transmission electron microscopy.
Polymerization Reactor Modeling in Industry – An Overview of Concepts and Tools
Authors: Mueller Philipp A. , Richards John R. , Wijnands Paul E. M.
Published: March 2010

Summary: The description of polymerization reactors by means of fundamental mathematical models is a challenging problem. At the same time, these models offer a very powerful tool for process control, monitoring, optimization, scale‐up, and operator training and often allow for a better understanding of underlying mechanisms. Some approaches and tools used in industry to meet these challenges are illustrated. The scope and complexity of polymerization models developed and applied to industrial processes are shown. In addition to kinetic aspects of the model development some emphasis is given to the thermodynamic description of phase behavior and phase partitioning in polymerization reactors. Also, the important task of a careful and thorough parameter evaluation is briefly discussed as this is a prerequisite of predictive modeling. Finally, some typical model predictions are illustrated with experimental data.
Kinetics of Nitroxide Mediated Radical Polymerization of Styrene with Unimolecular Initiators
Authors: Zhou Mingxiao , McManus Neil T. , Vivaldo‐Lima Eduardo , Lona Liliane M. F. , Penlidis Alexander
Published: March 2010

Summary: This study examined the kinetics of nitroxide‐mediated radical polymerization of styrene with unimolecular (alkoxyamine) initiators. Control of polymerization rate and polymer molecular weight in unimolecular nitroxide‐mediated radical polymerization was studied by looking at the effects of the three main factors: initiator concentration, temperature, and initiator molecular weight on polymerization rate, molecular weight and polydispersity. In addition, the behavior of the unimolecular initiating systems was compared to that of the corresponding bimolecular system. The effective TEMPO concentration and degree of self‐initiation of styrene were proved to be significant in dictating magnitudes of molecular weight averages and widths of molecular weight distribution.
Modeling of L‐lactide Polymerization by Reactive Extrusion
Authors: Banu Ionut , Puaux Jean‐Pierre , Bozga Grigore , Nagy Iosif
Published: March 2010

The kinetics of L‐lactide ring‐opening polymerization initiated by stannous octoate and triphenylphosphine was investigated in a batch apparatus (Haake Rheocord Mixer). Based on the experimental data, a kinetic model is developed, considering a coordination‐insertion mechanism. Reactive extrusion experiments were further conducted for the same polymerization process, on a co‐rotating twin screw extruder. The melted material flow and mixing was described by using the Ludovic® commercial simulator. Based on the developed kinetic model and simulated flow of L‐lactide polymerization mixture, a mathematical model of reactive extrusion process is formulated, describing the evolutions of monomer conversion and average molecular weight along the extruder. The model is predicting with a reasonable good accuracy the experimental data.
Relevance of backbiting and beta‐scission reactions in the free radical polymerization of Acrylonitrile
Authors: Dossi M. , Storti G. , Moscatelli D.
Published: March 2010

Summary: In this work, backbiting and beta‐scission reactions are investigated through Quantum Chemistry methods by adopting the Becke 3 parameters and Lee Yang Parr functional (B3LYP) and 6‐31G(d,p) basis set. Namely, the 1:3, 1:5 and 1:7 backbiting reactions are studied for acrylonitrile polymerization. It was found that the backbiting 1:5 is the most favorited because this kinetic event leads to the formation of a 6 membered transition state, while the backbiting 1:3 requires high activation energy due to the formation of a highly strained 4 membered ring. 7:3 backbiting reaction was also examined, since it is an alternative pathway that can explain the formation of defects generated by radicals in the third position. Simulations showed that this kinetic step is characterized by high rate constant because of its low activation energy.

The right and left beta‐scission reactions from the mid chain radicals formed by the considered backbiting reactions are also studied. Computational analysis demonstrated that all beta‐scission reactions are endothermic and both the right and left beta‐scission reactions have the same activation energy, which seems to be more influenced by the position of the mid chain radical.