bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of gamma radiation on the absorption spectra and optical energy gap of Li‐ doped ZnO thin films
Authors: Abu El‐Fadl A. , El‐Maghraby E. M. , Mohamad G. A.
Published: February 2004

We have studied the effect of subsequent gamma (γ) irradiation on the absorption spectra and the optical energy gap of ZnO thin films doped with Li (ZnO:Li). The optical transmission (T) and optical reflection (R) in the wavelength range 190∼800 nm of films deposited at 300 °C on sapphire, MgO or quartz substrates were measured. The dependence of the absorption coefficient α on photon energy hν was determined as a function of γ‐doses. The films show direct allowed interband transition that influenced by the gamma doses. Both the optical energy gap Eoptg and the absorption coefficient (α) were found to be γ‐dose dependent. The results can be discussed on the basis of γ‐irradiation‐induced defects in the film and on the film structure. The absorption coefficient exhibits exponential dependence on photon energy obeying Urbach's rule in the absorption edge. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Temperature dependence of the quadratic electrooptic effect and estimation of antipolarization of ADP
Authors: Ledzion R. , Bondarczuk K. , Kucharczyk W.
Published: February 2004

Measurements of the temperature dependence of the quadratic electrooptic coefficient |g1111‐g2211| of ADP were made. The coefficient is found to decrease with an increase in temperature. The results show that the intrinsic quadratic electrooptic coefficient |M1111‐M2211| defined in terms of polarization also dependes on temperature. Employing the temperature dependence of |M1111‐M2211| estimation of antipolarization in lowtemperature antiferroelectric phase of ADP is made. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Molecular ordering of 4O.2 compound in a dielectric medium at room temperature‐A theoretical approach
Authors: Ojha D. P. , Pisipati V. G. K. M.
Published: February 2004

The molecular ordering of N‐(4‐n‐butoxybenzylidene)‐4′‐ethyaniline [4O.2] in a dielectric medium (benzene) has been carried out on the basis of statistical mechanics and intermolecular forces. The atomic net charge and atomic dipole moment at each atomic centre has been evaluated using the CNDO/2 method. The modified Rayleigh‐Schrodinger perturbation theory with multicentered‐multipole expansion method has been employed to evaluate the long‐range intermolecular interactions, while ‘6‐exp’ potential function has been assumed for the short‐range interactions. The total interaction energy values obtained through these computations were used to calculate the probability of each configuration in a dielectric medium at room temperature (300K) using the MB‐formula. The flexibility of various interacting configuration has been studied in terms of variation of probability due to departure from the most probable configuration. A comparative picture of the molecular parameters like total energy, binding energy and total dipole moment has been given. An attempt has been made to analyse the characteristic features of nematogenic 4O.2 compound in terms of its relative order. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Structure and conformation of n‐ (t‐butoxycarbonyl)‐l‐valine‐l‐phenylalanine‐methyl ester (Boc‐Val‐Phe‐OMe)
Authors: Nallini A. , Saraboji K. , Ponnuswamy M. N. , Katti S. B.
Published: February 2004

The crystal structure of N‐ (t‐butoxycarbonyl) ‐ L‐valine‐L‐phenylalanine‐methyl ester (Boc‐Val‐Phe‐OMe), C20H30N2O5 was determined by X‐ray diffraction methods. The dipeptide crystallizes in orthorhombic space group P212121, with cell parameters a = 5.0680(1) Å, b = 13.8650(1) Å and c = 28.2630(1) Å, V = 2143.8(5) Å3, F.W. = 378.46, Z = 4, Dcalc = 1.173 Mg/m3, μ = 0.687 mm‐1, F000 = 816, CuKα = 1.5418 Å. The structure was solved by direct methods and final R1 and wR2 are 0.0659 and 0.1654, respectively. The peptide unit is in trans conformation [ω = 177.4(9)°]. The conformation angles ϕ1, ψ1, ϕ2 and ψ2 for the peptide backbone are: ‐96.5(13)°, 101.2(13)°, ‐123.9(12)° and 34.0(15)°. The N‐H…O and C‐H…O hydrogen bondings influence the packing of the molecules in the dipeptide crystal. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Structure and conformation of a nickel complex: {2‐Hydroxo‐3‐piperidine‐1‐yl‐methyl‐N,N′(bis‐5‐bromobenzylpropylenediimine)nickel(II)perchlorate}
Authors: Malathy Sony S. M. , Saraboji K. , Ponnuswamy M. N. , Manonmani J. , Kandasamy M. , Fun H.‐K.
Published: February 2004

The title compound, a nickel complex [C23H26N3O2Br2Ni.(ClO4)] (CCDC 199520) crystallizes in triclinic space group P$ \bar 1 $ with the cell parameters a = 10.2560(4), b = 10.8231(4), c = 12.0888(5)Å, α = 99.404(1), β = 99.780(1), γ = 92.252(1)° and V = 1301.49(9)Å3. The structure was solved by Patterson method and refined by full‐matrix least‐squares procedures to a final R = 0.0497 using 6287 observed reflections. In the complex, the piperidine ring takes chair conformation and the geometry around the Ni ion is slightly distorted square planar. The dihedral angle between the planes [N‐Ni‐N and O‐Ni‐O] is 9.4(1)°. The chelate ring containing both the nitrogen atoms adopts twisted boat conformation. The molecules in the crystal are stabilized by N‐H…O and C‐H…O types of hydrogen bonds in addition to a C‐H…π interaction. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electrochemical Parameters of Phenoxazine Derivatives in Solution and at Monolayer‐Modified Gold Electrodes
Authors: Kulys J. , Krikstopaitis K. , Scheller F. W. , Wollenberger U.
Published: February 2004

Electrochemical properties of β‐(10‐phenoxazinyl) propylamine (APPX) and β‐(10‐phenoxazinyl) propionic acid (PPX) have been studied in solution, and in immobilized state on gold electrodes modified with monolayers of cystamine and mercaptoundecanoic acid. A reversible diffusion‐controlled process of APPX and PPX was observed at a bare gold electrode. The electrochemical conversion of both compounds at modified gold electrodes was a quasi‐reversible diffusion‐controlled process. The redox potential of immobilized APPX (443 mV) was similar to the potential in solution, while the value of the immobilized PPX was 131 mV higher than in solution. The immobilized mediators were electrocatalytically active in the fungal peroxidase‐catalyzed hydrogen peroxide reduction.
Method for Determination of the Kinetic Parameters in Electrolytes Containing Surface‐Active Substances, Accounting for the Influence of Electrode Potential on the Changes of the Free Electrode Surface
Authors: Lazarov Veselin , Stoychev Dimitar
Published: February 2004

Based on the generally accepted concept of the influence exerted by the value of the electrode potential on the degree of coverage of the electrode surface with molecules of the adsorbed surface‐active substance (SAS), an equation has been derived in the present paper which meets the requirement of consistency in stability of the electrode surface and allows for calculating the kinetic parameters of an irreversible electrochemical process, such as they would have been if the value of the electrode potential did not influence the size of the free (uncoated) electrode surface. The method is based on the substantial difference between the rates of charging of the double electric layer and of establishing adsorption equilibrium on the electrode surface. In the general case of adsorption of organic molecules this difference is about 4 orders of magnitude, which gives grounds for the assumption that within the short time from the start of the galvanostatic pulse till the onset of a Faraday process the electrode surface remains unchanged, i.e., such as it has been at the equilibrium potential. The method is illustrated by processing of the experimental data for two SAS widely used in the industrial practice, which yield a sufficiently long transition time (τ>5 s) and at the same time change more or less the overpotential of the electrochemical process. The electric charge of the electrode changes its sign at that, which is an indication of the applicability of the method in the potential regions in which SAS are desorbed as well.
A Novel MCFC Cathode Material Modified by the EPD Technique
Authors: Chen L.J. , Zuo J. , Lin C.‐J.
Published: February 2004

The early deformation of the cathode material has been confirmed to be a significant factor in shortening the cell life. Thus, a new kind of cathode with both lower solubility and lighter deformation is highly desirable. In this work, a novel composite material, LiCoO2‐Ni, was prepared by the electrophoretic deposition (EPD) technique, which, remarkably, is able to reduce the deformation and dissolution of cathode materials simultaneously. It was demonstrated to be very promising for the MCFC industry.
Life Cycle Assessment of a Molten Carbonate Fuel Cell Stack
Authors: Lunghi P. , Bove R.
Published: February 2004

Fuel cells are considered to be ultra‐clean energy conversion systems because the pollutants emitted during their operating time are very low in concentration. For this reason, fuel cells can represent the answer to several environmental issues. What is important, however, is to carefully evaluate if the problem is really being solved, or just shifted. In other words, it is vital to consider not only the operating life, but also the pollution related to the construction, the disposal, the conversion of primary fuel into hydrogen and all the other related operations and systems.

The present study is the first step for evaluating the environmental impact related to the whole life cycle of a fuel cell system. In this paper, in fact, the authors, making use of the Life Cycle Assessment (LCA) approach, analyze the impact associated with a Molten Carbonate Fuel Cell Stack.

Since the MCFC construction can be considered a novel practice, this study can provide a significant indication for pollution reduction in the stack construction phase.
Lack of mutation of the folliculin gene in sporadic chromophobe renal cell carcinoma and renal oncocytoma
Authors: Nagy Anett , Zoubakov Dmitri , Stupar Zorica , Kovacs Gyula
Published: February 2004

Germline mutation of the folliculin gene (BHD) at chromosome 17p11.2 is associated with the development of multiplex hamartomas of the hair follicles, chromophobe renal cell carcinomas (RCC) and renal oncocytomas (RO). We have analyzed the folliculin gene with sequencing for mutations and the chromosome 17p11.2 with microsatellites for allelic changes in sporadic ROs and chromophobe RCCs. Allelic loss at chromosome 17 was seen in 8 of 8 chromophobe RCCs whereas none of the 8 RO showed alteration at this chromosomal region. Sequencing all exons from genomic DNA failed to disclose mutations of the folliculin gene in any of the tumors. We found a single nucleotide polymorphism (SNP) of G/A (nt 74) at the first exon in the untranslated region of the folliculin gene. We did not find a correlation between the SNP G/A or loss of the G allele and the expression level of either splice variants of the folliculin gene. Our data suggest the folliculin gene does not play a role in the tumorigenesis of sporadic chromophobe RCCs and renal oncocytomas. © 2004 Wiley‐Liss, Inc.
Polymorphisms of the interleukin‐1 β gene are associated with increased risk of non‐small cell lung cancer
Authors: Zienolddiny Shanbeh , Ryberg David , Maggini Valentina , Skaug Vidar , Canzian Federico , Haugen Aage
Published: February 2004

Lung cancer is one of the leading causes of cancer death worldwide. Tobacco smoking is the main risk factor for lung cancer. Less than 20% of smokers develop lung cancer in their lifetime, however, indicating individual variations in lung cancer risk. Pro‐inflammatory cytokines produced by inflammatory cells have been associated with inflammatory diseases and cancer. The IL1B gene, encoding IL‐1β cytokine, contains several single nucleotide polymorphisms (SNPs). Two of these are in the promoter region, at positions −511 (C‐T) and −31 (T‐C). These polymorphisms have been associated with increased risk of developing a number of inflammatory diseases and gastric carcinoma. We genotyped the 2 polymorphisms in 251 non‐small cell lung cancer patients from Norway and 272 healthy controls chosen from the general Norwegian population. The T allele at the −31 SNP (p = 0.01) and C allele at −511 SNP (p < 0.01) were over represented in lung cancer cases. The homozygote subjects were particularly at higher risk of lung cancer with odds ratio of 2.39 (95% CI = 1.29–4.44) for −31T/T and 2.51 (95% CI = 1.47–4.58) for −511C/C genotypes. In view of the significance of the p53 gene in lung carcinogenesis, we also analyzed the IL1B genotypes in relation to p53 mutations in the tumors. The results indicated that subjects having homozygote genotypes were more likely to have a mutation in the p53 gene (p = 0.05). This is the first study to provide evidence for an association of 1L1B gene polymorphisms with lung cancer risk. © 2004 Wiley‐Liss, Inc.
Perfusion of 99Tcm‐labeled CD105 Mab into kidneys from patients with renal carcinoma suggests that CD105 is a promising vascular target
Authors: Costello Brendan , Li Chenggang , Duff Sarah , Butterworth David , Khan Ali , Perkins Michael , Owens Susan , Al‐Mowallad Abdul Fattah , O'Dwyer Sarah , Kumar Shant
Published: February 2004

There is strong published and unpublished evidence that our CD105 Mab E9, which is highly reactive with angiogenic endothelial cells, could be a useful reagent to target the vasculature of solid tumors in man. Since Mab E9 does not cross‐react with animal tissues, we undertook here to evaluate its localization using human kidney as an ex vivo model. Perfusion was performed through the renal artery of 99Tcm‐labeled purified CD105 Mab in freshly excised kidneys from 7 patients with renal carcinoma. In all 7 cases, immunoscintigraphs showed the presence of well‐defined radioactive hot spots, which matched the positions of the tumors as identified by presurgery MRI scans and subsequent histopathologic examination. Importantly, in one instance, where a presurgery MRI scan had identified only one tumor, immunoscintigraphs showed 2 distinct hot spots of radioactivity. The pathology report confirmed that the additional hot spot corresponded to a small secondary well‐vascularized tumor. The implication of this finding is that the radiolabeled Mab, E9, may be of use in the detection of metastatic disease. That the labeling of tumors was specific was confirmed when prior perfusion of unlabeled mab E9 in 2 kidneys completely blocked the localization of 99Tcm‐conjugated Mab E9. Radioactivity in samples of tumor and normal tissue taken from 7 kidneys was counted in a gamma counter. In all cases, there was a greater uptake of radioactivity in tumors compared with the corresponding normal kidneys. The median values, adjusted per gram wet weight, for 99Tcm were 14.8 times (range, 4.8–113.0) greater in kidney tumors than in normal kidney tissue (p < 0.007). Immunofluorescent staining of cryostat sections of tumor tissues in each of the 7 cases showed strong and uniform localization of Mab E9 in tumor microvessels. Interestingly, chimeric staining of endothelial cells (ECs) was seen in an occasional microvessel segment. That is, while most of the ECs lining a microvessel were strongly stained, an occasional EC was negative. This was not an artifact of staining. Unstained ECs may be nonangiogenic or apoptotic since CD105 is a proliferation/activation‐associated antigen. Further investigations are warranted to establish the pharmacokinetics of 99Tcm‐labeled CD105 antibody in vivo. This would enable us to determine whether an apparently highly successful ex vivo study has the potential for tumor imaging/therapeutic vascular targeting in patients with cancer. © 2004 Wiley‐Liss, Inc.
Chromosome 13q12 region critical for the viability and growth of nasopharyngeal carcinoma hybrids
Authors: Cheng Yue , Lung Hong Lok , Wong Po Shan , Hao Da Cheng , Man Chim Shek , Stanbridge Eric John , Lung Maria Li
Published: February 2004

Allelic losses of chromosome 13 are often detected in nasopharyngeal carcinoma (NPC) and other cancers, implicating the presence of possible tumor suppressor genes (TSGs) on this chromosome. To identify candidate regions from larger and multiple lost areas observed from direct tumor studies, the technique of monochromosome transfer was utilized to provide functional evidence to verify and define these deletion findings. An intact chromosome 13 was transferred into the NPC HONE1 cell line. Resultant hybrids were used to map putative TSG activity. A critical region at 13q12 was non‐randomly eliminated in all surviving microcell hybrids around the marker D13S893; these hybrids were uniformly tumorigenic. Although a known TSG, BRCA2, is mapped close to this critical region, no aberrant expression of this gene was detected in microcell hybrids and other NPC cell lines. These results suggest that at least one novel growth control gene on chromosome 13q12, which is not the BRCA2 gene, is essential for hybrid selection and may play a critical role in tumorigenicity. © 2004 Wiley‐Liss, Inc.
Testicular cancer and occupational exposure to polyvinyl chloride plastics: A case‐control study
Authors: Hardell Lennart , Malmqvist Nils , Ohlson Carl‐Göran , Westberg Håkan , Eriksson Mikael
Published: February 2004

Exposure to polyvinyl chloride (PVC) plastics as a risk factor for testicular cancer was investigated. In total, 981 cases who were 20–75 years old and had reported to the Swedish Cancer Registry during 1993–1997 were included. One matched control from the population registry was used. Exposure was assessed by a questionnaire that was supplemented over the phone. Furthermore, an occupational hygienist qualified all exposures. In all, 791 matched pairs completed the questionnaire. Overall exposure to PVC plastics gave the odds ratio (OR)=1.35, 95% confidence interval (CI)=1.06–1.71, increasing with >10 year latency period to OR=1.45, 95% CI=1.06–1.98. No dose‐response relationships were found but rather an inverse relationship with the highest odds ratios in the lowest exposure category. In conclusion, no clear association with testicular cancer and exposure to PVC could be found in our study in contrast to a previous observation. © 2004 Wiley‐Liss, Inc.
Cumulative probability of PSA increase above 4.0 NG/ML in population‐based screening for prostate cancer
Authors: Ito Kazuto , Yamamoto Takumi , Ohi Masaru , Takechi Hiroyuki , Kurokawa Kohei , Suzuki Kazuhiro , Yamanaka Hidetoshi
Published: February 2004

Routine screening for prostate cancer remains controversial. However, it is very important to show how the optimal rescreening interval should be set for men who want to be screened after informed consent. To solve this issue, the risk of prostate‐specific antigen (PSA) increase above 4.0 ng/ml relative to baseline PSA levels and age was investigated. Between 1988 and 2000, 7,757 subjects screened twice or more and also with baseline PSA levels of 4.0 ng/ml or lower were enrolled in our study. All serum PSA levels were measured by E‐test Tosoh II PA assay at one center. Interval PSA levels for men undergoing screening with a greater than 1 year interval were calculated on the assumption that PSA levels changed over time in a simple exponential fashion. Then, the cumulative rate of freedom from PSA increase above 4.0 ng/ml was estimated using the Kaplan‐Meier technique stratified by baseline PSA ranges of 0.0 to 1.0, 1.1 to 2.0, 2.1 to 3.0 and 3.1 to 4.0 ng/ml and every 10 years of age ranges. Of the 7,757 subjects, 559 (7.2%) were expected to have had PSA levels increase above 4.0 ng/ml within 5 years after the baseline PSA measurements. The cumulative rate of freedom from the PSA increase above 4.0 ng/ml at 5 years was 98.7%, 92.9%, 70.3% and 38.5% in cases of baseline PSA levels of 1.0 ng/ml or lower, 1.1 to 2.0 ng/ml, 2.1 to 3.0 ng/ml and 3.1 to 4.0 ng/ml, respectively. The cumulative rates of freedom from the PSA increase were significantly decreased with the baseline PSA ranges being higher regardless of age range. Re‐screening interval should be set stratified by baseline PSA levels, regardless of age and race. Rescreening interval should be set at 1, 1 to 2 and 3 to 5 years for men with baseline PSA ranges of 2.1 to 4.0 ng/ml, 1.1 to 2.0 ng/ml and 0.0 to 1.0 ng/ml, respectively, in individual‐based screening. In mass screening system using PSA alone, rescreening interval should be set in the same manner as in individual‐based screening, except for men with baseline PSA levels of 1.1 to 2.0 ng/ml, which should be set at 1 year to avoid developing incurable prostate cancer. © 2004 Wiley‐Liss, Inc.
Survival after adjuvant 5‐FU treatment for stage III colon cancer in hereditary nonpolyposis colorectal cancer
Authors: de Vos tot Nederveen Cappel Wouter H. , Meulenbeld Hielke J. , Kleibeuker Jan H. , Nagengast Fokko M. , Menko Fred H. , Griffioen Gerrit , Cats Annemiek , Morreau Hans , Gelderblom Hans , Vasen Hans F.A.
Published: February 2004

In vitro studies suggest that a deficient mismatch repair (MMR) system reduces 5‐Fluorouracil cytotoxicity. Colon cancer (CC) in hereditary nonpolyposis colorectal cancer (HNPCC) is due to a dysfunctioning MMR gene that leads to microsatellite instability (MSI). Clinical studies on the efficacy of 5‐Fluorouracil (5‐FU) in MSI high tumours are contradictory. In a retrospective study, we compared the survival of subjects with stage III CC from HNPCC families that were treated with and without adjuvant 5‐FU. The Dutch HNPCC family registry was used. Information on adjuvant chemotherapy for stage III CC was obtained from subjects of families with a mutation and/or who fulfilled the AMS criteria or who were strongly suspicious for HNPCC. CC specific survival was calculated. Observation time was measured either until the date of death, date of a second primary CC or until the closing date of the study, i.e., June 1, 2001. Statistical analysis was done by Kaplan‐Meier survival analysis. A total of 92 subjects with stage III CC were included. Twenty‐eight of them (17 males) had adjuvant treatment with 5‐FU. The median follow‐up was 4 (range: 1–17) years; 8 subjects died of CC. The 5‐year survival was 70% (95% Cl: 49–90). Sixty‐four subjects (36 males) did not have adjuvant therapy. Their median follow‐up was 6 (range: 0–23) years. Twenty of them died of CC. The 5‐year survival in this group was also 70% (95% Cl: 59–83). To date, the selection of patients with CC for 5‐FU treatment is based on the stage rather than the biology of the tumour. In our study, the 5‐year survival of subjects treated with and without adjuvant 5‐FU did not differ. Further studies are necessary to elucidate the role of MSI in 5‐FU treatment of MSI‐H tumours in HNPCC. © 2004 Wiley‐Liss, Inc.
Familial association of histology specific breast cancers with cancers at other sites
Authors: Bermejo Justo Lorenzo , Hemminki Kari
Published: February 2004

Breast cancer histologies show important differences in their incidence pattern, method of detection and management. Aggregation of breast cancer occurs also in families diagnosed for cancer at sites different from the breast. Therefore, the familial association of histology specific breast cancers with cancers at other sites is of great interest. The nationwide Swedish Family‐Cancer Database was used to calculate standardised incidence ratios (SIRs) for breast cancer when parents or sibling were diagnosed with cancer at the most common sites. Significant SIRs were found when parents had breast, ovarian, laryngeal, endometrial, prostate, lung and colon cancers. If women were diagnosed before the age of 50 years, the SIRs were significant when parents were diagnosed with breast, ovarian, and prostate cancers, and leukaemia, and when siblings were diagnosed with squamous cell skin, pancreatic, breast and endometrial cancers. If mothers were diagnosed with breast cancer, histology‐specific SIRs were ranked as comedo > tubular > ductal > lobular; SIR for medullary carcinoma was not significant but it was high when mothers presented with ovarian cancer. Other associations were between the upper aerodigestive tract and lobular, colon and comedo, larynx and ductal cancer. Moreover, cervical cancer was associated with comedo and endometrial cancer with the medullary histology. In conclusion, histology‐specific breast cancers were associated with specific cancer sites and the strength of the association varied among histologies. © 2004 Wiley‐Liss, Inc.
Mutation analysis of the MLH1, MSH2 and MSH6 genes in patients with double primary cancers of the colorectum and the endometrium: A population‐based study in northern Sweden
Authors: Cederquist Kristina , Emanuelsson Monica , Göransson Ingela , Holinski‐Feder Elke , Müller‐Koch Yvonne , Golovleva Irina , Grönberg Henrik
Published: February 2004

Hereditary nonpolyposis colorectal cancer (HNPCC) is an autosomal dominant disorder that predisposes to predominantly colorectal and endometrial cancers due to germline mutations in DNA mismatch repair genes, mainly MLH1, MSH2 and in families with excess endometrial cancer also MSH6. In this population‐based study, we analysed the mutation spectrum of the MLH1, MSH2 and MSH6 genes in a cohort of patients with microsatellite unstable double primary tumours of the colorectum and the endometrium by PCR, DHPLC and sequencing. Fourteen of the 23 patients (61%) had sequence variants in MLH1, MSH2 or MSH6 that likely affect the protein function. A majority (10/14) of the mutations was found among probands diagnosed before age 50. Five of the mutations (36%) were located in MLH1, 3 (21%) in MSH2 and 6 (43%) in MSH6. MSH6 seem to have larger impact in our population than in other populations, due to a founder effect since all of the MSH6 families originate from the same geographical area. MSH6 mutation carriers have later age of onset of both colorectal cancer (62 vs. 51 years) and endometrial cancer (58 vs. 48 years) and a larger proportion of endometrial cancer than MLH1 or MSH2 mutation carriers. We can conclude that patients with microsatellite unstable double primary cancers of the colorectum and the endometrium have a very high risk of carrying a mutation not only in MLH1 or MSH2 but also in MSH6, especially if they get their first cancer diagnosis before the age of 50. © 2004 Wiley‐Liss, Inc.
WT1 is a tumor‐associated antigen in colon cancer that can be recognized by in vitro stimulated cytotoxic T cells
Authors: Koesters Robert , Linnebacher Michael , Coy Johannes F. , Germann Anja , Schwitalle Yvette , Findeisen Peter , von Knebel Doeberitz Magnus
Published: February 2004

The Wilms' tumor suppressor gene (WT1) has been shown to be overexpressed in acute and chronic leukemias and in a variety of solid human malignancies, including cancers of the breast and lung. In our present study, we investigated the potential role of WT1 gene in human colon cancer. WT1 mRNA and protein expression was analyzed in a panel of human colon cancer cell lines and primary colon carcinomas by RT‐PCR and Western blot analysis, respectively. A mutational screen of WT1′ zinc‐finger region was carried out by sequence analysis. Finally, using peptide‐stimulated cytotoxic T cells it was investigated whether WT1‐expressing colon tumor cells are a potential target for antigen‐specific immunotherapy. Medium to high abundant levels of WT1 mRNA were detected by RT‐PCR in 10 of 12 (83%) colon cell lines and by quantitative, real‐time RT‐PCR in 13 of 15 (87%) primary tumors, whereas only very low levels of expression were found in 2 primary tumors. Interestingly, however, low levels of WT1 mRNA were also detected in all samples derived from normal colon mucosa. When RT‐PCR products were examined by sequence analysis, both +KTS and −KTS splice isoforms but no zinc‐finger mutations were found, suggesting that the wild‐type form of the WT1 gene is expressed. To determine whether the WT1 protein can serve as a target antigen for immunotherapy, 2 HLA‐A2.1‐restricted WT1 peptides (Db126 and WH187) were used for the in vitro induction of WT1‐specific cytotoxic T lymphocytes (CTLs). The WH187‐specific CTLs not only lysed target cells pulsed exogenously with cognate peptide but also WT1‐expressing colon tumor cells in a HLA‐restricted manner. These findings identify the WT1 protein as an attractive target for the development of antigen‐specific immunotherapy in human colon cancer. © 2004 Wiley‐Liss, Inc.
Frequent alterations of Ras signaling pathway genes in sporadic malignant melanomas
Authors: Reifenberger Julia , Knobbe Christiane B. , Sterzinger Astrid A. , Blaschke Britta , Schulte Klaus W. , Ruzicka Thomas , Reifenberger Guido
Published: February 2004

Ras signaling is important for the intracellular transduction of mitogenic stimuli from activated growth factor receptors. We have investigated 37 sporadic malignant melanomas (15 primary cutaneous melanomas and 22 melanoma metastases) and 6 melanoma cell lines for mutations in the 3 Ras genes NRAS, KRAS and HRAS. All tumors and cell lines were additionally analyzed for mutation and expression of BRAF, which encodes a Ras‐regulated serine/threonine kinase with oncogenic properties, as well as for expression of RASSF1A, which encodes a Ras‐binding protein with tumor suppressor properties. Mutational analyses identified somatic NRAS mutations in 2 primary melanomas, 4 melanoma metastases and 2 cell lines. One melanoma metastasis showed a somatic KRAS mutation whereas HRAS mutations were not detected. Eight primary melanomas, 6 melanoma metastases and 4 melanoma cell lines carried BRAF mutations affecting the known hot‐spot codon 599. None of the tumors or cell lines with BRAF mutation demonstrated NRAS or KRAS mutations. Real‐time reverse transcription‐PCR showed that 8 melanomas (3 primary tumors, 5 melanoma metastases) had reduced RASSF1A transcript levels of ≤50% relative to benign melanocytic nevi and normal skin. Three melanoma cell lines lacked detectable RASSF1A transcripts. The RASSF1A gene promoter was hypermethylated in these 3 cell lines as well as in 6 of 8 melanomas with reduced RASSF1A mRNA levels. Treatment of the cell lines with 5‐aza‐2′‐deoxycytidine and trichostatin A resulted in demethylation of the RASSF1A promoter and re‐expression of RASSF1A transcripts. Most tumors and all cell lines with RASSF1A promoter methylation additionally carried BRAF or NRAS mutations, suggesting a synergistic effect of these aberrations on melanoma growth. Taken together, 57% of the investigated melanomas and 100% of the melanoma cell lines carried mutations in either NRAS, KRAS or BRAF. In addition, 22% of the melanomas and 50% of the cell lines showed reduced RASSF1A transcript levels. Thus, alterations of Ras pathway genes are of paramount importance in the pathogenesis of sporadic melanomas. © 2004 Wiley‐Liss, Inc.
Enhanced radiosensitivity of rat autochthonous mammary tumors by dietary docosahexaenoic acid
Authors: Colas Séverine , Paon Lénaic , Denis Fabrice , Prat Marie , Louisot Pascal , Hoinard Claude , Le Floch Olivier , Ogilvie Gregory , Bougnoux Philippe
Published: February 2004

Dietary docosahexaenoic acid (DHA), which integrates into tumor cell membranes, has been reported to enhance the efficacy against tumors of cytotoxic drugs that induce reactive oxygen species (ROS). Because ionizing radiation also generate ROS, we initiated a study to determine whether dietary DHA might sensitize mammary tumors to irradiation. Mammary tumors were induced by N‐methylnitrosourea (NMU) in Sprague‐Dawley rats. The optimal dose of radiation to examine the effect of DHA on tumor response to irradiation was determined to be 18 grays (Gy) using a 4–6 MeV electron beam (according to the depth of the target volume) delivered in a single fraction from a linear accelerator. Two groups of rats were fed a basal diet containing 7% of a mixture of peanut and rapeseed oils enriched with 8% of an oil containing either a low (palm oil) or high (DHASCO oil containing 40% DHA) DHA content. DHA group was equally subdivided into 2 groups without or with addition of vitamin E (100 IU/kg diet). Irradiation was carried out when the first tumor in each rat reached 1.5 cm2 and subsequent change in tumor size was documented over time. DHA level in adipose tissue, taken as a biomarker, was higher in the DHA supplemented group compared to the control group. Vitamin E level in liver, the best storage for this compound, was higher in the vitamin E supplemented DHA group compared to the DHA group. Tumor size decreased by 60% at 12 days after irradiation in the DHA group vs. 31% in the control group (p = 0.03) and 36% in the DHA plus vitamin E group. Therefore, dietary DHA sensitized mammary tumors to radiation. The addition of vitamin E inhibited the beneficial effect of DHA, suggesting that this effect might be mediated by oxidative damage to the peroxidizable lipids. © 2004 Wiley‐Liss, Inc.
IMGT standardized criteria for statistical analysis of immunoglobulin V‐REGION amino acid properties
Authors: Pommié Christelle , Levadoux Séverine , Sabatier Robert , Lefranc Gérard , Lefranc Marie‐Paule
Published: February 2004

IMGT, the international ImMunoGeneTics information system® (http://imgt.cines.fr) is a high‐quality integrated information system specializing in immunoglobulins (IG), T cell receptors (TR) and major histocompatibility complex (MHC) of human and other vertebrates. IMGT comprises IMGT/LIGM‐DB, the comprehensive database of IG and TR sequences from human and other vertebrates (76 846 sequences in September 2003). In order to define the IMGT criteria necessary for standardized statistical analyses, the sequences of the IG variable regions (V‐REGIONs) from productively rearranged human IG heavy (IGH) and IG light kappa (IGK) and lambda (IGL) chains were extracted from IMGT/LIGM‐DB. The framework amino acid positions of 2474 V‐REGIONs (1360 IGHV, 585 IGKV, 529 IGLV) were numbered according to the IMGT unique numbering. Two statistical methods (correspondence analysis and hierarchic classification) were used to analyze the 237 framework positions (80 for IGHV, 79 for IGKV, 78 for IGLV), for three properties (hydropathy, volume and chemical characteristics) of the 20 common amino acids. Results of the analyses are shown as standardized two‐dimensional representations, designated as IMGT Colliers de Perles statistical profiles. They provide a characterization of the amino acid properties at each framework position of the expressed IG V‐REGIONs, and a visualization of the resemblances and differences between heavy and light, and between kappa and lambda sequences. The standardized criteria defined in this paper, amino acid positions and property classes, will be useful to study the mutations and allele polymorphisms, to establish correlations between amino acids in the IG and TR protein three‐dimensional structures and to extract new knowledge from V‐like domains of chains, other than IG and TR, belonging to the immunoglobulin superfamily. Copyright © 2004 John Wiley & Sons, Ltd.
Protein stabilization by salt bridges: concepts, experimental approaches and clarification of some misunderstandings
Authors: Bosshard Hans Rudolf , Marti Daniel N. , Jelesarov Ilian
Published: February 2004

Salt bridges in proteins are bonds between oppositely charged residues that are sufficiently close to each other to experience electrostatic attraction. They contribute to protein structure and to the specificity of interaction of proteins with other biomolecules, but in doing so they need not necessarily increase a protein's free energy of unfolding. The net electrostatic free energy of a salt bridge can be partitioned into three components: charge–charge interactions, interactions of charges with permanent dipoles, and desolvation of charges. Energetically favorable Coulombic charge–charge interaction is opposed by often unfavorable desolvation of interacting charges. As a consequence, salt bridges may destabilize the structure of the folded protein. There are two ways to estimate the free energy contribution of salt bridges by experiment: the pKa approach and the mutation approach. In the pKa approach, the contribution of charges to the free energy of unfolding of a protein is obtained from the change of pKa of ionizable groups caused by altered electrostatic interactions upon folding of the protein. The pKa approach provides the relative free energy gained or lost when ionizable groups are being charged. In the mutation approach, the coupling free energy between interacting charges is obtained from a double mutant cycle. The coupling free energy is an indirect and approximate measure of the free energy of charge–charge interaction. Neither the pKa approach nor the mutation approach can provide the net free energy of a salt bridge. Currently, this is obtained only by computational methods which, however, are often prone to large uncertainties due to simplifying assumptions and insufficient structural information on which calculations are based. This state of affairs makes the precise thermodynamic quantification of salt bridge energies very difficult. This review is focused on concepts and on the assessment of experimental methods and does not cover the vast literature. Copyright © 2004 John Wiley & Sons, Ltd.
Factors contributing to the development of aluminum resistance in the Madeiran maize germplasm
Authors: Pinheiro de Carvalho Miguel Â. A. , Slaski Jan J. , Abreu Ivo , Ganança Filipe T. , dos Santos Teresa M. M. , Freitas Lurdes , Clemente Vieira Maria R. , Nunes Antonieta , Domingues Ana , Taylor Gregory J.
Published: February 2004

Forty genotypes representing maize genetic diversity from the Island of Madeira were screened for resistance to aluminum (Al) in nutrient solution. Seeds of maize were obtained from local farmers from field plots spread around the island in a range of altitudes from 99 to 1000 m above sea level. The content of ionic aluminum and the pH of soils cultivated with maize were determined. The mean pH value of all examined soils was 4.9, while the mean ionic Al content was 0.76 cmol kg–1. Seventy‐two hours (h) exposure to 100 and 200 μM Al followed by a 48 h recovery period of 4‐day old seedlings revealed significant differences in Al resistance in the Madeiran maize germplasm. Root survival and regrowth exceeding 80 % of the seedlings were observed in 22 and 8 of the tested genotypes screened at 100 and 200 μM Al in nutrient solution. High Al resistance among Madeiran maize genotypes appeared not to be associated with the lower pH of soil, and did not correlate with the amount of soil Al3+ or the altitude at the site of collection. The high level of Al resistance of the maize cultivars indicates an initial genetic trait enhanced by open pollination of maize.
Immobilization of heavy metals in soils by the application of bauxite residues: pot experiments under field conditions
Authors: Friesl Wolfgang , Horak Othmar , Wenzel Walter W.
Published: February 2004

In previous greenhouse experiments red mud, a residue of the alumina industry, was identified as effective amendment for in situ fixation of heavy metals. In the present study, we further evaluated the efficiency and potential drawbacks of red mud in an outdoor pot experiment. Application of 5 % (w/w) red mud (RM) should reveal possible drawbacks of red mud due to indigenous pollutants such as As, Cr, and V. Three soils from arable land in Lower Austria named Untertiefenbach (U) (Eutric Cambisol), Weyersdorf (W) (Dystric Cambisol), and Reisenberg (R) (Calcic Chernozem) were spiked with Cd, Zn, Cu, Ni, and V at two concentration levels in 1987, two soils originate from long‐term industrially polluted sites, located in Carinthia (Arnoldstein – Rendzic Leptosol; Zn, Cd, and Pb) and Tyrol (Brixlegg – Dystric Fluvisol; Cu, Zn). Zea mays was cultivated in pots for three months in outdoor conditions. Extraction with 1 M NH4NO3 was used to assess the influence of RM on the labile metals. Lability of Cd, Zn, Ni, and Pb was reduced upon RM treatment on a sandy soil up to 91 %, 94 %, 71 %, and 83 % of the control, respectively. Metal accumulation in shoots was reduced for Cd and Zn up to 54 % and for Ni up to 75 % (soil W), but not for Pb (soil A). Addition of RM (5 % w/w) increased the total As, Cr, and V concentrations in soils by 5, 20, and 50 mg kg–1, respectively. Whereas the lability of Cr was not affected, 1 M NH4NO3‐extractable As and V exceeded the trigger value for water quality according to Prüeß (1994). Lability of Cu increased upon RM application, especially on the Cu polluted industrial soil (B), while Cu toxicity appeared to be reduced as indicated by the higher corn biomass production. Red mud holds promise as soil amendment in terms of reduction Cd, Zn, and Ni bioavailability. However, at additions as high as 5 % (w/w) large As, Cr, and V concentrations of this material may limit its application.
Degradation of organotin compounds in organic and mineral forest soils
Authors: Huang Jen‐How , Matzner Egbert
Published: February 2004

Broad industrial application of organotin compounds (OTC) leads to their release into the environment. OTC are deposited from the atmosphere into forest ecosystems and may accumulate in soils. Here, we studied the degradation of methyltin and butyltin compounds in a forest floor, a mineral, and a wetland soil with incubation experiments at 20 °C in the dark. OTC degraded slowly in soils with half‐lives estimated from 0.5 to 15 years. The first order degradation rate constants of OTC in soils ranged from 0.05 to 1.54 yr–1. The degradation rates in soils were generally in the order mono‐ ≥ di‐ > tri‐substituted OTC. Stepwise dealkylation was observed in all cases of di‐substituted OTC, but only in some cases of tri‐substituted OTC. Decomposition rates of OTC in the forest floor were higher than in wetland and mineral soils. Tetramethyltin in the gas phase was not detected, suggesting little tin methylation in the wetland soils. Slow degradation of OTC in soils might lead to long‐term storage of atmospherically deposited OTC in soils.
Soil biochemical and microbial indices in wet tropical forests: Effects of deforestation and cultivation
Authors: Dinesh R. , Ghoshal Chaudhuri S. , Sheeja T. E.
Published: February 2004

Little information is available about the long‐term effects of deforestation and cultivation on biochemical and microbial properties in wet tropical forest soils. In this study, we evaluated the general and specific biochemical properties of soils under evergreen, semi‐evergreen, and moist deciduous forests and adjacent plantations of coconut, arecanut, and rubber, established by clear felling portions of these forests. We also examined the effects of change in land use on microbial indices and their interrelationships in soils.

Significant differences between the sites occurred for the biochemical properties reflecting soil microbial activity. Microbial biomass C, biomass N, soil respiration, N mineralization capacity, ergosterol, levels of adenylates (ATP, AMP, ADP), and activities of dehydrogenase and catalase were, in general, significantly higher under the forests than under the plantations. Likewise, the activities of various hydrolytic enzymes such as acid phosphomonoesterase, phosphodiesterase, casein‐protease, BAA‐protease, β‐glucosidase, CM‐cellulase, invertase, urease, and arylsulfatase were significantly higher in the forest soils which suggested that deforestation and cultivation markedly reduced microbial activity, enzyme synthesis and accumulation due to decreased C turnover and nutrient availability. While the ratios of microbial biomass C : N and microbial biomass C : organic C did not vary significantly between the sites, the ratios of ergosterol : biomass C and ATP : biomass C,qCO2 and AEC (Adenylate Energy Charge) levels were significantly higher in the forest sites indicating high energy requirements of soil microbes at these sites.
Zuordnung des Munsell‐Codes zu einem Farbnamen nach bodenkundlichen Kriterien
Authors: Albrecht Christoph , Huwe Bernd , Jahn Reinhold
Published: February 2004

Eine der zentralen Informationen für die Bodenklassifikation ist die Farbe. Bei Profilaufnahmen wird sie entweder verbal oder durch den Munsell‐Code beschrieben. Während der Name schnell und ohne Hilfsmittel zu bestimmen ist, hat der Munsell‐Code den Vorteil, dass er auf einem standardisierten Farbraum basiert und deshalb numerische Vergleiche zwischen einzelnen Farben gezogen werden können. Da in vielen bodenkundlichen Datensätzen nur der Farbname angegeben ist, ist die rechnergestützte Auswertung dieser Information oft nicht möglich. Um dieses Problem zu umgehen, wurde ein System entwickelt, mit dem zu jedem bodenkundlichen Farbnamen der mittlere Munsell‐Code bestimmt werden kann. Es ist in der plattformübergreifenden Programmiersprache Tcl/Tk als freie Software programmiert.
Characterisation and identification of proteinaceous binding media (animal glues) from their amino acid profile by capillary zone electrophoresis
Authors: Kaml Isabella , Vcelakova Katerina , Kenndler Ernst
Published: February 2004

A capillary electrophoretic method for identifying different species of proteinaceous binders – collagen, egg white, and milk casein – is described. It allows characterisation of the proteins on the basis of the amino acid profiles obtained after their acidic hydrolysis. The profiles of the underivatised amino acids are recorded directly by capillary zone electrophoresis at pH 2.26 with the aid of a conductivity detector, thus eliminating the need for a derivatisation step. Identification is carried out by means of different relative peak areas of the amino acids. A scheme is given for identification, which is based on the main markers, hydroxyproline, proline, glycine, glutamic acid, and serine and valine.
Investigating the history of prehistoric glues by gas chromatography–mass spectrometry
Authors: Regert Martine
Published: February 2004

Although organic materials are very sensitive to biochemical alteration processes, they may be preserved for millennia in various archaeological contexts. Remains of adhesives made during prehistory were discovered at different sites, in the form of residues adhering to flint tools and ceramic vessels or as free lumps in sediment. To characterise the natural substances exploited for adhesive production during late prehistory, we undertook GC and GC/MS analysis of 90 samples from 8 sites dating from the Neolithic to Iron Age periods. This paper discusses our approach to the study of organic adhesives preserved in archaeological contexts, with a particular focus on the presentation of the various categories of organic adhesives that we analysed and the choice of chromatographic conditions adapted to the specificity of such samples. The results obtained show that birch bark tar, a triterpenoid adhesive made by destructive distillation of white birch bark, was predominantly used during the neolithic period even though other materials such as various barks or organic fossil substance were also used. During the Bronze and Iron ages, which follow the Neolithic period, adhesive production is evolving through the expansion of the range of the natural substances used (identification of diterpenoid pine resin) and the addition of beeswax as a plasticiser to birch bark tar. By combining chromatographic analysis and archaeological data, it was thus possible to follow the evolution of adhesive making at the end of prehistory, testifying to the inventiveness of the craftsmen whatever the period considered.
Microbial diversity in biodeteriorated monuments as studied by denaturing gradient gel electrophoresis
Authors: Gonzalez Juan M. , Saiz‐Jimenez Cesareo
Published: February 2004

Studies of the microorganisms living on cultural assets and their potential damaging effects begin with an understanding of the microbial diversity present in such samples. Recently, molecular techniques have started to attract considerable interest since they do not require the culture of microorganisms in order to detect their presence. The basic protocol followed during microbial diversity analysis on cultural heritage assets utilizes electrophoretic techniques for separating highly homologous sequences. At present, Denaturing Gradient Gel Electrophoresis (DGGE) is the most frequently reported technique for separating DNA fragments during microbial diversity studies of art objects. In this report, we describe DGGE profiling techniques, show the most common applications, and present some examples of their use in microbial diversity studies on cultural heritage.