bluuebunny/crossref_metadata_2025 huggingface dataset:
Electrocatalytic Oxidation of Some Carbohydrates by Nickel/Poly(o‐Aminophenol) Modified Carbon Paste Electrode
Authors: Ojani Reza , Raoof Jahan‐Bakhsh , Fathi Shahla
Published: July 2008

This study investigates the electrocatalytic oxidation of glucose and some other carbohydrates on nickel/poly(o‐aminophenol) modified carbon paste electrode as an enzyme free electrode in alkaline solution. Poly(o‐aminophenol) was prepared by electropolymerization using a carbon paste electrode bulk modified with o‐aminophenol and continuous cyclic voltammetry in HClO4 solution. Then Ni(II) ions were incorporated to electrode by immersion of the polymeric modified electrode having amine group in 1 M Ni(II) ion solution. Cyclic voltammetric and chronoamperometric experiments were used for the electrochemical study of this modified electrode; a good redox behavior of Ni(OH)2/NiOOH couple at the surface of electrode can be observed, the capability of this modified electrode for catalytic oxidation of glucose and other carbohydrates was demonstrated. The amount of α and surface coverage (Γ*) of the redox species and catalytic chemical reaction rate constant (k) for each carbohydrate were calculated. Also, the electrocatalytic oxidation peak currents of all tested carbohydrates exhibit a good linear dependence on concentration and their quantification can be done easily.
Voltammetric Behavior of Trolox in Methanol and Ethanol Solutions
Authors: Karbarz Monika , Malyszko Jan
Published: July 2008

Electrochemical oxidation of trolox on carbon electrodes was investigated by means of some voltammetric techniques in methanol and ethanol solutions in the presence of an excess of acid or base. The oxidation occurs according to EEC mechanism, i.e. in two quasireversible one‐electron steps yielding the corresponding phenoxyl radical and, subsequently, phenoxonium cation. Phenoxonium ion decays because of a pseudo‐first order follow‐up chemical reaction with nucleophiles. The electrochemical behavior of trolox is strongly influenced by the surrounding environmental conditions. In acidic solutions, a single two‐electron anodic wave was observed. The presence of a strong base drastically improves the stability of the intermediate, phenoxyl radical. Under these conditions, the two‐electron wave was found to split into its one‐electron components over a range of scan rates. The resolution is much distinct in ethanol. Simulations with DigiSim software were used to fit the cyclic voltammograms in order to estimate thermodynamic and kinetic data for the reaction mechanism studied.
Electrochemical Monitoring of DNA Hybridization by Multiwalled Carbon Nanotube Based Screen Printed Electrodes
Authors: Karadeniz Hakan , Erdem Arzum , Caliskan Ayfer
Published: July 2008

The application of multiwalled carbon nanotube (MWCNT) based screen printed graphite electrodes (SPEs) was explored in this study for the electrochemical monitoring of DNA hybridization related to specific sequences on Hepatitis B virus (HBV) DNA. After the microscopic characterization of bare MWCNT‐SPEs and DNA immobilized ones was performed, the optimization of assay has been studied. The development of screen printing process combined with nanomaterial based disposable sensor technology leads herein a great opportunity for DNA detection using differential pulse voltammetry (DPV) by measuring the guanine oxidation signal observed at +1.00 V in the presence of DNA hybridization between HBV probe and its complementary, target. The detection limit estimated for signal to noise ratios =3 corresponds to 96.33 nM target concentration in the 40 μL samples. The advantages of carbon nanotube based screen printed electrode used for electrochemical monitoring of DNA hybridization are discussed with sensitivity, selectivity and reproducibility in comparison with previous nanomaterial based electrochemical transducers developed for DNA or other biomolecular recognitions.
Influence of DNA repair gene polymorphisms on the initial repair of MMS‐induced DNA damage in human lymphocytes as measured by the alkaline comet assay
Authors: Ryk Charlotta , Routledge Michael N. , Allan James M. , Wild Christopher P. , Kumar Rajiv , Lambert Bo , Hou Saimei
Published: July 2008

We have applied the alkaline comet assay to study the functional impact of gene polymorphisms in base excision repair (APEX1 Asp148Glu, XRCC1 Arg194Trp, XRCC1 Arg399Gln) and homologous recombination repair (XRCC3 Thr241Met, NBS1 Glu185Gln), two pathways that play crucial roles in the repair of DNA damage induced by methylmethane sulphonate (MMS). We also examined the effect of polymorphisms in mismatch repair (MLH1 −93 A/G) and nucleotide excision repair (XPD Lys751Gln) as putative negative controls based on the limited roles of these pathways in MMS‐induced repair. Phytohemagglutinin‐stimulated peripheral lymphocytes from 52 healthy individuals were treated with MMS and allowed to repair for 0, 15, 40, or 120 min after a 6‐min washing step. DNA damage was measured as a pseudo‐percentage score (comparable to % tail DNA) converted from a total visual score calculated from the distribution of cells with different degrees of damage (normal, mild, moderate and severe). The repair was faster at the beginning of the observation period than towards the end, and was not complete after 2 hr. Presence of the APEX1 148Asp, XRCC3 241Met or NBS1 185Gln alleles were significantly associated with a high pseudo‐percentage score (above median) at early time points, with the APEX1 effect being most prolonged (up to 40 min after washing, odds ratio 5.6, 95% confidence interval 2.0–15.5). No significant effects were seen with the XRCC1 Arg194Trp, XRCC1 Arg399Gln, MLH1 −93A/G and XPD Lys751Gln polymorphisms. Our results provide evidence for the functional nature of the variant alleles studied in the APEX1, XRCC3, and NBS1 genes. Environ. Mol. Mutagen., 2008. © 2008 Wiley‐Liss, Inc.
Comparison of metabolite profiles generated in Aroclor‐induced rat liver and human liver subcellular fractions: Considerations for in vitro genotoxicity hazard assessment
Authors: Obach R. Scott , Dobo Krista L.
Published: July 2008

Because it is well known that metabolites of chemicals and drugs are frequently the ultimate species responsible for genotoxicity and carcinogenicity, in vitro testing to identify the human genotoxicity hazard potential of new chemicals and drugs routinely utilizes liver S‐9 fraction from rats treated with Aroclor 1254 as a system that can generate metabolites. However, it is frequently questioned as to whether such an in vitro metabolite generation system is the most relevant for human risk, or whether the assay would be better served by using a human‐derived in vitro system. To address this, 16 common drugs have been examined for profiles of metabolites in Aroclor‐induced rat liver S‐9 and pooled human liver S‐9. Metabolite profiles were compared using high pressure liquid chromatography coupled with ion trap mass spectrometry, in line with ultraviolet or radiometric detection to help make semiquantitative comparisons. Results showed that, with few exceptions, metabolites generated in the human system were also generated in the rat system. Also, in several cases the rat system generated considerably more metabolites, suggesting that there is a potential that positive genotoxicity findings could be caused by metabolites that have no relevance to humans. These findings suggest that when conducting in vitro genotoxicity testing using the Aroclor‐induced rat liver S‐9 system, knowledge of the metabolite profile in the system is important, and a comparison to the profile generated in human liver S‐9 could be of value when interpreting the genotoxicity results. Environ. Mol. Mutagen., 2008. © 2008 Wiley‐Liss, Inc.
Comparative study of Euler/Euler and Euler/Lagrange approaches simulating evaporation in a turbulent gas–liquid flow
Authors: Groll R. , Jakirlić S. , Tropea C.
Published: July 2008

This study deals with the Reynolds‐averaged Navier–Stokes simulation of evaporation in a turbulent gas–liquid flow in a three‐dimensional duct, focussing on the results obtained by a four‐equation turbulence model within the framework of the Euler/Euler approach for multiphase flow calculations: in addition to the two‐equation k−ε model describing the turbulence of the continuous (C) phase, the computational model employs transport equations for the turbulence kinetic energy of the disperse (D) phase and for the velocity covariance q=〈{u}D{u}C〉D. In the present study, the evaporation model according to Abramzon and Sirignano (Int. J. Heat Mass Transfer 1989; 32:1605–1618) has been extended by introducing an additional transport equation for a newly defined quantity ā, defined as the phase‐interface surface fraction. This allows the change in the drop diameter to be quantified in terms of a probability density function. The source term in the equation describing the dynamics of the volumetric fraction of the dispersed phase αD is related to the evaporation time scale τΓ. The performance of the new model is evaluated by performing a comparative analysis of the results obtained by simulating a polydispersed spray in a three‐dimensional duct configuration with the results of the Euler/Lagrange calculations performed in parallel. Prior to these calculations, some selected (solid) particle‐laden flow configurations were computationally examined with respect to the validation of the background, four‐equation, eddy‐viscosity‐based turbulence model. Copyright © 2008 John Wiley & Sons, Ltd.
Histone deacetylase 11 regulates oligodendrocyte‐specific gene expression and cell development in OL‐1 oligodendroglia cells
Authors: Liu Hedi , Hu Qichen , D'ercole A. Joseph , Ye Ping
Published: July 2008

Both in vivo and in vitro studies indicate a correlation between reduced acetylation of histone core proteins and oligodendrocyte development. The nature of these histone modifications and the mechanisms mediating them remain undefined. To address these issues, we utilized OL‐1 cells, a rat nontransformed oligodendrocyte cell line, and primary oligodendrocyte cultures. We found that the acetylated histone H3 at lysine 9 and lysine 14 (H3K9/K14ac) is reduced in both the myelin basic protein (MBP) and proteolipid protein (PLP) genes of maturing oligodendroglial OL‐1 cells, and furthermore, this temporally correlates with increases in MBP, PLP, and histone deacetylase (HDAC) 11 expression. Disruption of developmentally‐regulated histone H3 deacetylation within the MBP and PLP genes by the HDAC inhibitor trichostatin A blunts MBP and PLP expression. With its increased expression, interaction of HDAC 11 with acetylated histone H3 and recruitment of HDAC 11 to the MBP and PLP genes markedly increases in maturing OL‐1 cells. Moreover, suppressing HDAC 11 expression with small interfering RNA significantly (1) increases H3K9/K14ac globally and within the MBP and PLP genes, (2) decreases MBP and PLP mRNA expression, and (3) blunts the morphological changes associated with oligodendrocyte development. Our data strongly support a specific role for HDAC 11 in histone deacetylation and in turn the regulation of oligodendrocyte‐specific protein gene expression and oligodendrocyte development. © 2008 Wiley‐Liss, Inc.
Sedation and antihistamines: an update. Review of inter‐drug differences using proportional impairment ratios
Authors: McDonald Kathleen , Trick Leanne , Boyle Julia
Published: July 2008

Background

The use of antihistamines (AHs) has been associated with cognitive and psychomotor impairments, largely caused by the sedative properties of many of these drugs. Due to the ambulant nature of the population using AHs, it is important to evaluate these effects using standardised methodology and psychometric tests. A previous extensive review of the literature collated the results of studies of H1 receptor antagonists to determine the extent to which a particular AH produced impairments on a battery of psychometric tests by calculating a proportional impairment ratio for each AH.

Objective

In light of a number of major studies published following the previous review, and the development of the second and new‐generation AHs, the present review aims to add to the database and update the review, using the same methodology.

Results and Conclusion

The newer generation AHs appear to be the least impairing, and the first generation, as expected, appear to be the most impairing. There are also differences within the AH drug generations. The review highlights the necessity to consider the sedating potential of AHs, along with other factors such as efficacy, when prescribing AHs to ambulant patients. Copyright © 2008 John Wiley & Sons, Ltd.
Pesticide exposure as risk factor for non‐Hodgkin lymphoma including histopathological subgroup analysis
Authors: Eriksson Mikael , Hardell Lennart , Carlberg Michael , Åkerman Måns
Published: July 2008

We report a population based case–control study of exposure to pesticides as risk factor for non‐Hodgkin lymphoma (NHL). Male and female subjects aged 18–74 years living in Sweden were included during December 1, 1999, to April 30, 2002. Controls were selected from the national population registry. Exposure to different agents was assessed by questionnaire. In total 910 (91 %) cases and 1016 (92%) controls participated. Exposure to herbicides gave odds ratio (OR) 1.72, 95% confidence interval (CI) 1.18–2.51. Regarding phenoxyacetic acids highest risk was calculated for MCPA; OR 2.81, 95% CI 1.27–6.22, all these cases had a latency period >10 years. Exposure to glyphosate gave OR 2.02, 95% CI 1.10–3.71 and with >10 years latency period OR 2.26, 95% CI 1.16–4.40. Insecticides overall gave OR 1.28, 95% CI 0.96–1.72 and impregnating agents OR 1.57, 95% CI 1.07–2.30. Results are also presented for different entities of NHL. In conclusion our study confirmed an association between exposure to phenoxyacetic acids and NHL and the association with glyphosate was considerably strengthened. © 2008 Wiley‐Liss, Inc.
Caspase‐3 enhances lung metastasis and cell migration in a protease‐independent mechanism through the ERK pathway
Authors: Cheng Yu‐Jung , Lee Chien‐hsin , Lin Yu‐Ping , Huang Jyun‐Yuan , Su Chung‐Chen , Chang Wen‐Tsan , Yang Bei‐Chang
Published: July 2008

Caspase‐3 is known as a cysteine protease that primarily executes the cell death program. However, some tumors express higher levels of caspase‐3 in positive correlation with malignancy. Here, we showed that caspase‐3 can promote tumor metastasis in a protease‐independent mechanism. Ectopic expression of caspase‐3 enhanced lung metastasis and cell motility of caspase‐3 deficient MCF‐7 cells. By contrast, caspase‐3 siRNA reduced the invasiveness and metastasis ability of A549 cells that express high level of caspase‐3. Moreover, caspase‐3 induced ERK activation. Alteration of caspase‐3 by introducing non‐processable mutation at its cleavage site or treatment of caspase‐3 inhibitor did not diminish the caspase‐3‐associated increases in ERK phosphorylation and cell migration. Confocal microscopy study showed that caspase‐3 was not physically associated with ERK. Inhibiting ceramide formation by blockage of the ceramide synthase or acid sphingomyelinase activity resulted in significant reduction of ERK phosphorylation and cell migration. In summary, caspase‐3 induces ERK activation through a ceramide‐dependant, protease activity‐independent mechanism, which represents a novel role of caspase‐3 in tumor metastasis. © 2008 Wiley‐Liss, Inc.
IGF1 is a modifier of disease risk in hereditary non‐polyposis colorectal cancer
Authors: Reeves Stuart G. , Rich Dominique , Meldrum Cliff J. , Colyvas Kim , Kurzawski Grzegorz , Suchy Janina , Lubinski Jan , Scott Rodney J.
Published: July 2008

Patients diagnosed with HNPCC harbouring a confirmed germline mutation in DNA mismatch repair (MMR) genes have an 80% lifetime risk of developing an epithelial malignancy. There is, however, considerable variation in the age of disease onset in these patients. Insulin‐like growth factor‐I (IGFI) has been implicated in colorectal cancer (CRC), and elevated plasma IGFI levels are associated with both sporadic and hereditary CRC risk. In this study, we further investigate the cytosine‐adenine (CA) dinucleotide repeat polymorphism located near the promoter region of IGF1 and its relation to early onset CRC risk in 443 Australian and Polish MMR gene mutation carriers using DNA sequencing, Kaplan‐Meier survival curves and Cox proportional hazard regression analysis. A significantly smaller number of IGF1 CA repeats was observed in the Polish patient population, which was associated with an earlier age of disease onset compared to the Australian patients. The threshold for the observed modifying effect was again shown to be in patients with 17 or less CA repeats compared to those with 18 or more. Furthermore, when MMR mutation group (i.e., MLH1 or MSH2), gender and family clustering were included in the final Cox model we observed a more robust trend for the role of the IGF1 CA repeat in predicting age of disease onset in HNPCC patients. In addition, this effect was shown to be equal in both MLH1 and MSH2 mutation carrier groups and not restricted to a particular MMR subgroup (p = 0.001). We conclude that the IGF1 CA repeat is an important modifier of disease onset in HNPCC and the first polymorphism to yield consistent results across different populations. © 2008 Wiley‐Liss, Inc.
Folate deprivation induces BCRP (ABCG2) expression and mitoxantrone resistance in Caco‐2 cells
Authors: Lemos Clara , Kathmann Ietje , Giovannetti Elisa , Dekker Henk , Scheffer George L. , Calhau Conceição , Jansen Gerrit , Peters Godefridus J.
Published: July 2008

Folates can induce the expression and activity of the breast‐cancer‐resistance‐protein (BCRP) and the multidrug‐resistance‐protein‐1 (MRP1). Our aim was to study the time‐dependent effect of folate deprivation/supplementation on (i) BCRP and MRP expression and (ii) on drug resistance mediated by these transporters. Therefore Caco‐2 colon cancer cells usually grown in standard RPMI‐medium containing supraphysiological folic acid (FA) concentrations (2.3 μM; high‐folate, HF) were gradually adapted to more physiological folate concentrations (1 nM leucovorin (LV) or 1 nM FA; low‐folate, LF), resulting in the sublines Caco‐2‐LF/LV and Caco‐2‐LF/FA. Caco‐2‐LF/LV and LF/FA cells exhibited a maximal increase of 5.2‐ and 9.6‐fold for BCRP‐mRNA and 3.9‐ and 5.7‐fold for BCRP protein expression, respectively, but no major changes on MRP expression. Overexpression of BCRP in the LF‐cells resulted in 3.6‐ to 6.3‐fold resistance to mitoxantrone (MR), which was completely reverted by the BCRP inhibitor Ko143. On the other hand, LF‐adapted cells were markedly more sensitive to methotrexate than the HF‐counterpart, both after 4‐hr (9,870‐ and 23,923‐fold for Caco‐2‐LF/LV and LF/FA, respectively) and 72‐hr (11‐ and 22‐fold for Caco‐2‐LF/LV and LF/FA, respectively) exposure. Immunofluorescent staining observed with a confocal‐laser‐scan‐microscope revealed that in Caco‐2 cells (both HF and LF), BCRP is mainly located in the cytoplasm. In conclusion, folate deprivation induces BCRP expression associated with MR resistance in Caco‐2 cells. The intracellular localization of BCRP in these cells suggests that this transporter is not primarily extruding its substrates out of the cell, but rather to an intracellular compartment where folates can be kept as storage. © 2008 Wiley‐Liss, Inc.
The Ikaros splice isoform, Ikaros 6, immortalizes murine haematopoietic progenitor cells
Authors: Ruiz Anna , Williams Owen , Brady Hugh J.M.
Published: July 2008

Alternative pre‐mRNA splicing is emerging as a major control point in both the initiation and progression of tumourigenesis. Overexpression of the dominant negative Ikaros splice isoform, Ik6, is found in many human cancers particularly leukaemias. Ik6 has been demonstrated to have a role in cell survival in both myeloid‐ and lymphoid cytokine‐dependent cell lines. To investigate the oncogenic potential of Ik6, we retrovirally transduced murine haematopoietic progenitor cells with Ik6 and have analysed the effects on proliferation and differentiation of these precursors using myeloid and lymphoid in vitro colony formation assays. We found that Ik6 can immortalize haematopoietic progenitor cells in myeloid conditions. Using an in vivo transplantation assay, we found that Ik6 favours reconstitution by haematopoietic precursors. These findings suggest that Ik6 may play an important role in the generation of the leukaemic phenotype. © 2008 Wiley‐Liss, Inc.
Impact of antioxidant supplementation on chemotherapeutic toxicity: A systematic review of the evidence from randomized controlled trials
Authors: Block Keith I. , Koch Amanda C. , Mead Mark N. , Tothy Peter K. , Newman Robert A. , Gyllenhaal Charlotte
Published: July 2008

Much debate has focused on whether antioxidants interfere with the efficacy of cancer chemotherapy. The objective of this study is to systematically review the randomized, controlled clinical trial evidence evaluating the effects of concurrent use of antioxidants with chemotherapy on toxic side effects. We performed a search of literature from 1966‐October 2007 using MEDLINE, Cochrane, CinAhl, AMED, AltHealthWatch and EMBASE databases. Randomized, controlled clinical trials reporting antioxidant‐based mitigation of chemotherapy toxicity were included in the final tally. Searches were performed following a standardized protocol for systematic reviews. Only 33 of 965 articles considered, including 2,446 subjects, met the inclusion criteria. Antioxidants evaluated were: glutathione (11), melatonin (7), vitamin A (1), an antioxidant mixture (2), N‐acetylcysteine (2), vitamin E (5), selenium (2), L‐carnitine (1), Co‐Q10 (1) and ellagic acid (1). The majority (24) of the 33 studies included reported evidence of decreased toxicities from the concurrent use of antioxidants with chemotherapy. Nine studies reported no difference in toxicities between the 2 groups. Only 1 study (vitamin A) reported a significant increase in toxicity in the antioxidant group. Five studies reported the antioxidant group completed more full doses of chemotherapy or had less‐dose reduction than control groups. Statistical power and poor study quality were concerns with some studies. This review provides the first systematically reviewed evidence that antioxidant supplementation during chemotherapy holds potential for reducing dose‐limiting toxicities. However, well‐designed studies evaluating larger populations of patients given specific antioxidants defined by dose and schedule relative to chemotherapy are warranted. © 2008 Wiley‐Liss, Inc.
Association study of CCR5 delta 32 polymorphism among the HLA‐DRB1 Caucasian population in Northern Paraná, Brazil
Authors: Muxel Sandra Marcia , Borelli Sueli Donizete , Amarante Marla Karine , Voltarelli Julio Cesar , Aoki Mateus Nobrega , de Oliveira Carlos Eduardo Coral , Ehara Watanabe Maria Angelica
Published: July 2008

Chemokines are important determinants of early inflammatory response. The CC chemokine receptor 5 (CCR5) delta 32 variant results in a nonfunctional form of the chemokine receptor and has been implicated in a variety of immune‐mediated diseases. In the present study, polymerase chain reaction (PCR) for genomic deoxyribonucleic acid (DNA) samples, using specific CCR5 oligonucleotide primers surrounding the breakpoint deletion, detected a 225‐basepair (bp) product from the normal CCR5 allele and a 193‐bp product from the 32 bp deletion allele. Human leukocyte antigen (HLA) class II (DRB1) typing was performed by PCR‐sequence‐specific primer (PCR‐SSP). The aim of this study was to evaluate the association of HLA‐DRB1 and CCR5 genetic polymorphisms. To evaluate the frequency distributions of CCR5 delta 32 polymorphisms in a Brazilian population and their association with allelic distribution of HLA genes, DRB1; a total of 120 Caucasian individuals from northern Paraná, Brazil, were tested. The CCR5/CCR5 genotype was found in 108 individuals (90%) and only one carried the CCR5 delta 32 allele homozygous genotype (0.0238), while 12 (10%) carried the CCR5 delta 32 allele heterozygous genotype. The observed frequency for the CCR5 delta 32 allele was 0.05 in the population studied. The results revealed a CCR5 delta 32 allele occurrence with HLA‐DRB1*01 and DRB1*04 (P<0.05). It is possible that HLA‐DRB1*01 and DRB1*04 alleles could be associated with the delta 32‐bp deletion of CCR5. J. Clin. Lab. Anal. 22:229–233, 2008. © 2008 Wiley‐Liss, Inc.
Evaluation of enzyme‐linked immunosorbent assays for detecting circulating antibodies toCandida albicans
Authors: Prince Harry E. , Yeh Cindy , Alem Navid , Asalkhou Mandana , Hamedi Nina , Alem Neda , Alem Mehdi
Published: July 2008

Published studies indicate thatCandida albicansantibody assays utilizing cytoplasmic antigens offer greater utility for identifying cases of systemic candidiasis when compared with assays utilizing cell wall components. We assessed the performance characteristics of a commercially available system that utilizes cytoplasmic antigens to measureC. albicansIgG, IgM, and IgA (Candida Detect ELISA reagents). Intra‐assay variation was ≤5%, inter‐assay variation was ≤10%, and good linearity was observed for all the three antibody isotypes. Results for specimens stored under various conditions were comparable to those obtained initially. Inter‐laboratory reproducibility was excellent; qualitative concordance was ≥93% for all the three isotypes, with slopes andR2values approaching 1.0 in linear regression analyses. Seroprevalence in persons without apparent systemic candidiasis was evaluated using three different serum panels; seroprevalence rates ranged from 24 to 32% for IgG, 2–14% for IgM, and 15–36% for IgA. Seroprevalence rates in a panel of sera containing antibodies to other fungi were similar to rates observed in panels from individuals without systemic candidiasis. These findings demonstrate the acceptable performance of assay systems employing Candida Detect ELISA reagents. J. Clin. Lab. Anal. 22:234–238, 2008. © 2008 Wiley‐Liss, Inc.
Detection of ciguatoxin in fish tissue using sandwich ELISA and neuroblastoma cell bioassay
Authors: Campora Cara Empey , Dierking Jan , Tamaru Clyde S. , Hokama Yoshitsugi , Vincent Douglas
Published: July 2008

The applicability of a new enzyme‐linked immunoassay (ELISA) for detecting ciguatoxin (CTX) in fish tissue was evaluated by testing three fish species commonly implicated in ciguatera fish poisoning in Hawaii. A total of 164 individual almaco jack (Seriola rivoliana) and greater amberjack (S. dumerili) and a total of 175 individuals of the blue‐spotted grouper (Cephalopholis argus) were caught at various locations in the Hawaiian Islands. Muscle tissue from each individual was assessed for the presence of CTX using two methods: a semi‐quantitative ELISA that was recently developed for detecting picogram levels of CTX in fish extract and a neuroblastoma (NB) cell assay commonly used to screen for marine toxins in fish. Results of the tests were highly correlated, with the ELISA indicating the presence of CTX in 9.4% of all fish samples, and the NB assay indicating toxicity in 6.8% of the fish samples. We conclude that the ELISA produces reliable and accurate results that are consistent with those provided by the accepted NB assay and that the ELISA has potential for future applications in screening fish populations for CTX. J. Clin. Lab. Anal. 22:246–253, 2008. © 2008 Wiley‐Liss, Inc.
Development of an enzyme‐linked immunosorbent assay for the detection of ciguatoxin in fish tissue using chicken immunoglobulin Y
Authors: Empey Campora Cara , Hokama Yoshitsugi , Yabusaki Kenichi , Isobe Minoru
Published: July 2008

A sandwich enzyme‐linked immunosorbent assay was developed to detect ciguatoxin (CTX) in fish tissue. The assay utilizes two antibodies, chicken immunoglobulin Y specific to the ABCD domain of CTX and a mouse monoclonal immunoglobulin G–hor‐seradish peroxidase conjugate specific to the JKLM domain of CTX. The sensitivity, working range, cross reactivity, accuracy, precision, and reproducibility were examined. J. Clin. Lab. Anal. 22:239–245, 2008. © 2008 Wiley‐Liss, Inc.
RNA from Borna disease virus in patients with schizophrenia, schizoaffective patients, and in their biological relatives
Authors: Nunes Sandra Odebrechet Vargas , Itano Eiko Nakagawa , Amarante Marla Karine , Reiche Edna Maria Vissoci , Miranda Helen Cristina , de Oliveira Carlos Eduardo Coral , Matsuo Tiemi , Vargas Heber Odebrechet , Watanabe Maria Angelica Ehara
Published: July 2008

Numerous interactions of the immune system with the central nervous system have been described recently. Mood and psychotic disorders, such as severe depression and schizophrenia, are both heterogeneous disorders regarding clinical symptomatology, the acuity of symptoms, the clinical course, the treatment response, and probably also the etiology. Detection of p24 RNA from Borna disease virus (BDV) by the reverse transcriptase polymerase chain reaction in patients with schizophrenia, schizoaffective disorder, and in their biological relatives was evaluated. The subjects were 27 schizophrenic and schizoaffective patients, 27 healthy controls, 20 relatives without psychiatric disease, and 24 relatives with mood disorder, who attended the Psychiatric Ambulatory of Londrina State University, Paraná, Brazil. The subjects were interviewed by structured diagnostic criteria categorized according to the Diagnostic and Statistical Manual of Mental Disorders‐IV, axis I, (SCID‐IV). The mean duration of illness in schizophrenic and schizoaffective patients was 15.341±1.494 years and the median age at onset was 22.4±7.371 years. There were no significant differences in gender (P=0.297), age (P=0.99), albumin (P=0.26), and body mass index (kg/m2) (p=0.28), among patients, controls, and relatives. Patients and biological relatives had significantly higher positive p24 RNA BDV detection than controls (P=0.04); however, the clinical significance of BDV remains to be clarified. J. Clin. Lab. Anal. 22:314–320, 2008. © 2008 Wiley‐Liss, Inc.
Serum N‐acetyl‐β‐D‐glucosaminidase profiles in type 1 diabetes secondary complications: causes of changes and significance of determination
Authors: Jovanović V.B. , Dimitrijević‐Srecković V.S. , Mandić Ljuba M.
Published: July 2008

The connection between changes in the activity of serum N‐acetyl‐β‐D‐glucosaminidase (NAG, E.C.3.2.1.30) and iso‐enzymes and degree of secondary complications was analyzed in four groups of type 1 diabetic patients (n=69): without complications (n=22); with retinopathy (n=16); with retinopathy and polyneuropathy (n=13), and with retinopathy, neuropathy, and nephropathy (n=18). In all groups statistically significant higher (P<0.001) percent fraction of A form (83.84±6.09, 84.37±5.74, 81.76±6.02, 76.37±7.38%, resp.) and lower (P<0.001, P<0.01) fraction of B form (15.87±5.65, 15.66±5.74, 18.33±5.98, 23.63±7.38, resp.) in total NAG compared with the control (A=69.38±4.79%, B=30.61±4.78%) were found. The differences in A as well as B forms between diabetic groups were not statistically significant. Significant strong positive correlations between total NAG and glycemia (0.494–0.623), total NAG and A form (0.934–0.966), and A form and glycemia (0.512–0.638) were found in all groups. No correlation was found between the fractions of B and A forms, except in the fourth group. The A form of diabetic patients in the fourth group was more acidic compared with the control and other diabetic groups. It was concluded that the changes in serum NAG and iso‐enzymic profiles in diabetes are the consequence of its increased exocytose, especially of the A form, in hyperglycemia and posttranslational modifications of iso‐enzymes. The total activity of serum NAG and iso‐enzymic profiles cannot be used for monitoring the development and distinction of type 1 diabetes secondary complications. J. Clin. Lab. Anal. 22:307–313, 2008. © 2008 Wiley‐Liss, Inc.
Combined local and systemic methotrexate treatment of viable ectopic pregnancy: Outcomes of 31 cases
Authors: Smorgick Noam , Vaknin Zvi , Pansky Moti , Halperin Reuvit , Herman Arie , Maymon Ron
Published: July 2008

Purpose.

Medical treatment of viable unruptured ectopic pregnancies by systemic methotrexate (MTX) is controversial due to elevated failure rates. This study describes a combined local and systemic MTX administration and compares the outcomes between viable ectopics in different locations.

Methods.

This retrospective study evaluated 31 patients treated with combined local (sonographically guided) and systemic MTX for viable, unruptured ectopic pregnancies. Success was defined by pregnancy resolution without surgical intervention. Details on subsequent pregnancies were obtained via telephone questionnaires.

Results.

The ectopic pregnancies were located in the fallopian tube (n = 23), cesarean section scar (n = 5), and intramural portion of the tube (interstitial pregnancy) (n = 3). β‐Human chorionic gonadotropin levels and gestational weeks were similar. The combined treatment was successful in 73.9%, 100%, and 66.7% of cases, respectively (p > 0.05). Details regarding reproductive outcomes were available for 28 women (90.3%). Eighteen of the 24 women attempting to conceive became pregnant, and 15 of these had at least one live birth. There were three subsequent tubal pregnancies, all in patients with previous tubal pregnancies.

Conclusion.

Combined MTX administration is effective and safe for treating viable cesarean scar pregnancies but is less successful for viable tubal or interstitial pregnancies. Reproductive outcomes following the combined MTX treatment are comparable to other treatment modalities for ectopic pregnancy. © 2008 Wiley Periodicals, Inc. J Clin Ultrasound, 2008
Optimizing environmental scanning electron microscopy of spheroidal reaggregated neuronal cultures
Authors: Uroukov Ivan S. , Patton David
Published: July 2008

Electrophysiological recordings from hen embryo brain spheroidal reaggregates on penetrating 3D multielectrode arrays could be understood more easily if the surface structure was known in more detail. Electrophysiological activity, as grouped spikes in trains, is acquired from spheroids, indicating the inner formation a neuronal network. To this end, spheroids can be observed by environmental scanning electron microscopy. Live spheroids collapse when the supporting water is evaporated. By careful adjustment of the chamber pressure it is possible to observe fully hydrated fixed spheroids. A thin film of water tends to prevent a clear view of the surface detail. This can be evaporated to reveal the surface while taking steps to avoid both inadvertent shrinkage and rewetting. Conventional SEM shows a very different surface that is rich in protruding cell bodies and fibers. The images are compared and interpreted with some images of the surface using transmission electron microscopy. Microsc. Res. Tech., 2008. © 2008 Wiley‐Liss, Inc.
Assembling and imaging of his‐tag green fluorescent protein on mica surfaces studied by atomic force microscopy and fluorescence microscopy
Authors: Liu Zhiguo , Zu Yuangang , Fu Yujie , Zhang Zhonghua , Meng Ronghua
Published: July 2008

The adsorption of his‐tag green fluorescent protein (GFPH6) onto the mica surfaces has been studied by atomic force microscopy (AFM) and laser confocal fluorescence microscopy. By controlling the adsorption conditions, separated single GFPH6 and GFPH6 monolayer can be adsorbed and formed on mica surfaces. In present experiments, based on the AFM measurement, we found that the adsorbed GFPH6 was bound on the mica surface with its β‐sheets. The formed GFPH6 monolayer on mica surfaces was flat, uniform, and stable. Some applications of the formed monolayer have been demonstrated. The formed monolayer can be used as a substrate for DNA imaging and AFM mechanical lithography. Microsc. Res. Tech., 2008. © 2008 Wiley‐Liss, Inc.
Comparing hypoxia‐targeting potential of 99mTc(CO)3‐labeled 2‐nitro and 4‐nitroimidazole
Authors: Mallia Madhava B , Subramanian Suresh , Mathur Anupam , Sarma H.D. , Venkatesh Meera , Banerjee Sharmila
Published: July 2008

Non‐invasive determination of hypoxia is an important problem in clinical nuclear medicine. Although 18F‐fluoromisonidazole is used clinically for hypoxia determination, the short half‐life (t1/2=109.77 min), high cost and less availability of cyclotrone‐produced 18F make 99mTc (t1/2=6 h)‐based agents more desirable. With this aim, 99mTc(CO)3‐labeled iminodiacetic acid derivatives of 2‐ and 4‐nitroimidazole are investigated for their ability to target hypoxic tumors. A bifunctional chelating agent, N, N‐bis[(tert‐butoxycarbonyl)methyl]‐2‐bromoethylamine, was synthesized in the first step, which was then conjugated to the nitroimidazoles in the second step. The tert‐butyl ester derivatives formed were hydrolyzed to obtain the iminodiacetic acid derivatives of corresponding nitroimidazoles. The radiolabeling of the iminodiacetic acid derivatives with [99mTc(CO)3(H2O)3]+ core was carried out following a reported protocol. Biodistribution of the prepared complexes was carried out in Swiss mice bearing fibrosarcoma tumor. The 2‐nitroimidazole complex showed a steady retention in activity (∼1.5% injected dose per gram [%ID/g]) in tumor throughout the period of study (3 h) indicating that it may be localized in the hypoxic cells. The 4‐nitroimidazole counterpart, however, showed an initial uptake of ∼4.6%ID/g at 30 min post injection, which was then observed to wash out rapidly. Copyright © 2008 John Wiley & Sons, Ltd.
Ultrastructural investigation of coelomocytes in representatives of Naidinae and Rhyacodrilinae (Annelida, Clitellata, Tubificidae)
Authors: Envall Ida , Erséus, Christer , Gustavsson Lena M.
Published: July 2008

Various types of free‐floating cells are found in the coelomic fluid of representatives of several annelid groups. The ultrastructure of these “coelomocytes,” however, has been studied to a limited degree. In this study, we used a transmission electron microscope to investigate the coelomocytes in specimens of five species of Naidinae and three species of Rhyacodrilinae (all oligochaetous clitellates within the family Tubificidae). These were compared with each other and with previously described coelomocytes of representatives of other oligochaete taxa. Only one distinguishable coelomocyte type was found in the studied specimens: a round to oblong cell without pseudopodia or other appendages, primarily containing membrane‐bound granules of varying electron density, a prominent network of rough endoplasmic reticulum, and free ribosomes. This type differs to a great extent from most of the previously described coelomocytes, but shows similarities to certain types found in members of Enchytraeidae and Megascolecidae. Although we noticed some variation, we did not find any ultrastructural characters in these cells obviously useful for phylogenetic studies within Tubificidae. J. Morphol., 2008. © 2008 Wiley‐Liss, Inc.
The external gills of anuran amphibians: Comparative morphology and ultrastructure
Authors: Nokhbatolfoghahai M. , Downie J.R.
Published: July 2008

The external gills of anuran amphibians are transient structures, covered by the development of the operculum and regressing soon afterwards. Their functional role has been regarded as equivocal. However, detailed morphological analysis has been limited. Analysis of 21 species from six families using scanning and transmission electron microscopy revealed diversity at the anatomical and cellular levels in extent and length of gill filaments, numbers of surface ciliated cells, width of water‐blood barrier distance, and evidence of gill motility. The most highly developed external gills were found in species with delayed hatching, such as Phyllomedusa trinitatis, or in species in which hatchlings hang from the surface film of temporary ponds, such as Phrynohyas venulosa in which gills added 26–38% to body surface area. In one family, the bufonids, all four species examined had poorly developed gills, but in other families where we examined several species, the hylids and leptodactylids, there was considerable diversity of external gills, suggesting flexible adaptation to incubation and hatching environment. J. Morphol., 2008. © 2008 Wiley‐Liss, Inc.
Mobile larynx in Mongolian gazelle: Retraction of the larynx during rutting barks in male Mongolian gazelle (Procapra gutturosa Pallas, 1777)
Authors: Frey Roland , Gebler Alban , Olson Kirk A. , Odonkhuu Daria , Fritsch Guido , Batsaikhan, Nyamsuren , Stuermer Ingo W.
Published: July 2008

This study provides the first evidence of pronounced temporary laryngeal descent in a bovid species. An elaborate acoustic display is prominent in male courtship behavior of polygynous Mongolian gazelle. During rut, rounding up of females is accompanied by continuous head‐up barking by dominant males. Throughout the rut their evolutionarily enlarged larynx descends to a low mid‐neck resting position. In the course of each bark the larynx is additionally retracted toward the sternum by 30% of the resting vocal tract length. A geometric model of active larynx movements was constructed by combining results of video documentation, dissection, skeletonization, and behavioral observation. The considerable distance between resting position and maximal laryngeal descent suggests a backward tilting of the hyoid apparatus and an extension of the thyrohyoid connection during the retraction phase. Return to the resting position is effected by strap muscles and by the elastic recoil of the pharynx and the thyrohyoid connection. An intrapharyngeal inflation of the peculiar palatinal pharyngeal pouch of adult males is inferred from a short‐time expansion of the ventral neck region rostral to the laryngeal prominence. The neck of adult dominant males is accentuated by long gray guard hairs during the rut. The passive swinging of the heavy larynx of adult males during locomotion gives the impression of a handicap imposed on rutting males. Apparently, this disadvantage becomes outweighed by the profits for reproductive success. J. Morphol., 2008. © 2008 Wiley‐Liss, Inc.
Measurement of cytotoxic and interstitial components of cerebral edema in acute hepatic failure by diffusion tensor imaging
Authors: Rai Vijan , Nath Kavindra , Saraswat Vivek A. , Purwar Ankur , Rathore Ram K.S. , Gupta Rakesh K.
Published: July 2008

Purpose

To use diffusion tensor imaging (DTI) metrics for measuring cytotoxic and interstitial components of cerebral edema (CE) in acute hepatic failure (AHF) patients. CE is a major complication in patients with AHF.

Materials and Methods

DTI was performed in 20 patients with AHF and 15 controls. Ten patients underwent repeat imaging after recovery from encephalopathy. Various regions of interest (ROIs) were drawn in the white and deep gray matter of the brain for the quantitation of fractional anisotropy (FA), mean diffusivity (MD), spherical isotropy (CS), linear anisotropy (CL), and planar anisotropy (CP) values.

Results

Significantly decreased MD values were observed in most brain ROIs in patients compared to controls. Significantly decreased FA, CL with increased CS values was also observed. In survivors with normal clinical profile after 3 weeks, a significant increase in MD and FA values were associated with decreased CS values in some regions compared to baseline study; however, it was still significantly changed compared to controls.

Conclusion

Decreased MD and increased CS associated with decreased FA represent cytotoxic and interstitial components of CE, respectively. Incomplete normalization of these metrics in survivors after 3 weeks clinical recovery may be due to incomplete metabolic recovery. J. Magn. Reson. Imaging 2008. © 2008 Wiley‐Liss, Inc.
Neurotrimin is an estrogen‐regulated determinant of peripheral sympathetic innervation
Authors: Krizsan‐Agbas Dora , Pedchenko Tetyana , Smith Peter G.
Published: July 2008

Mechanisms underlying axon degeneration in peripheral neuropathies and during normal remodeling are poorly understood. Because estrogen induces widespread sympathetic axon degeneration in female reproductive tract smooth muscle, we surveyed estrogen‐regulated genes in rat myometrium. Microarray analysis revealed that the neural cell adhesion protein neurotrimin (Ntm) was markedly up‐regulated 6 hr and down‐regulated 24 hr after injection of 17β‐estradiol, and real time RT‐PCR confirmed this pattern of expression. Protein analysis by Western blotting showed that uterine Ntm protein is also up‐regulated in vivo 6–24 hr following estrogen injection and that Ntm protein is increased selectively in the myometrium during the high‐estrogen phase of the estrous cycle. Cultured myometrial smooth muscle cells display perinuclear accumulations of Ntm protein, and 17β‐estradiol also increases intracellular levels of Ntm and its secretion into the culture medium. To determine if neurotrimin is required for estrogen‐induced sympathetic pruning, sympathetic neurons were cocultured with uterine smooth muscle cells transfected with siRNA directed against Ntm. Although estrogen inhibited neurite outgrowth in nontransfected cocultures, estrogen's ability to reduce sympathetic outgrowth was impaired substantially following Ntm down‐regulation. This supports a role for neurotrimin in mediating estrogen‐induced sympathetic pruning in some peripheral targets. Together with earlier studies, these findings support the idea that physiological sympathetic axon degeneration is a multifactorial process requiring dynamic regulation of multiple repellant proteins. © 2008 Wiley‐Liss, Inc.
Involvement of independent mechanism upon poly(ADP‐ribose) polymerase (PARP) activation in methylmercury cytotoxicity in rat cerebellar granule cell culture
Authors: Sakaue Motoharu , Mori Naoko , Okazaki Maiko , Ishii Mayuka , Inagaki Yayoi , Iino Yuka , Miyahara Kiyomi , Yamamoto Mai , Kumagai Takeshi , Hara Shuntaro , Yamamoto Masako , Arishima Kazuyoshi
Published: July 2008

Poly(ADP‐ribose) polymerase (PARP) activation plays a role in repairing injured DNA, while its overactivation is involved in various diseases, including neuronal degradation. In the present study, we investigated the use of a PARP inhibitor, 3,4‐dihydro‐5‐[4‐(1‐piperidinyl)butoxy]‐1(2H)‐isoquinolinone (DPQ), whether methylmercury‐induced cell death in the primary culture of cerebellar granule cells involved PARP activation. DPQ decreased the methylmercury‐induced cell death in a dose‐dependent manner. Unexpectedly, this protective effect was DPQ specific; none of the other PARP inhibitors—1,5‐dihydroxyisoquinoline, 3‐aminobenzamide, or PJ34—affected neuronal cell death. Methylmercury‐induced cell death involves the decrease of glutathione (GSH) and production of reactive oxygen species. Therefore, to understand the mechanism by which DPQ inhibits cytotoxicity, we first studied the effect of DPQ on buthionine sulfoximine– or diethyl maleate–induced death of primary cultured cells and human neuroblastoma IMR‐32 cells, both of which are mediated by GSH depletion. DPQ inhibited the cell death of both cultured cells, but it did not restore the decrease of cellular GSH by buthionine sulfoximine to the control level. Second, we evaluated the antioxidant activity of PARP inhibitors by methods with ABTS (2‐2′‐azinobis(3‐ethylbenzothiazoline 6‐sulfonate) or DPPH (1,1‐diphenyl‐2‐picrylhydrazyl) used as a radical because antioxidants also efficiently suppress methylmercury‐induced cell death. The antioxidant activity of DPQ was the lowest among the tested PARP inhibitors. Taken together, our results indicate that DPQ effectively protects cells against methylmercury‐ and GSH depletion–induced death. Furthermore, they suggest that DPQ exerts its protective effect through a mechanism other than PARP inhibition and direct antioxidation, and that PARP activation is not involved in methylmercury‐induced neuronal cell death. © 2008 Wiley‐Liss, Inc.