bluuebunny/crossref_metadata_2025 huggingface dataset:
Estimating anisotropic aquifer parameters by artificial neural networks
Authors: Lin Hsien‐Tsung , Ke Kai‐Yuan , Chen Chu‐Hui , Wu Shih‐Ching , Tan Yih‐Chi
Published: July 2010

In recent years, many approaches have been developed using the artificial neural networks (ANN) model incorporated with the Theis analytical solution to estimate the effective hydrological parameters for homogeneous and isotropic porous media, such as the Lin and Chen approach (ANN approach) and the principal component analysis (PCA)‐ANN approach. The above methods assume a full superimposition of the type curve and the observed drawdown and try to use the first time‐drawdown data as a match point to make a fine approximation of the effective parameters. However, using first time‐drawdown data or early time‐drawdown data does not always allow for an accurate estimation of the hydrological parameters, especially for heterogeneous and anisotropic aquifers. Therefore, this article corrects the concept of the superimposed plot by modifying the ANN approach and the PCA‐ANN approach, as well as incorporating the Papadopoulos analytical solution, to estimate the transmissivities and storage coefficient for anisotropic, homogeneous aquifers. The ANN model is trained with 4000 training sets of the well function, and tested with 1000 sets and 300 sets of synthetic time‐drawdown generated from the homogeneous and heterogeneous parameters, respectively. In situ observation data from the time‐drawdown at station Shi‐Chou on the Choushui River alluvial fan, Taiwan, is further adopted to test the applicability and reliability of the proposed methods, as well as provide a basis for comparison with the Straight‐line method and the Type‐curve method. Results suggest that both of the modified methods perform better than the original ones, and using late time‐drawdown to optimize the effective parameters is shown to be better than using early time‐drawdown. Additionally, results indicate that the modified ANN approach is better than the modified PCA‐ANN approach in terms of precision, while the efficiency of the modified PCA‐ANN approach is approximately three times better than that of the modified ANN approach. Copyright © 2010 John Wiley & Sons, Ltd.
Understanding salt mobilization from an irrigated catchment in south‐eastern Australia
Authors: Selle B. , Thayalakumaran T. , Morris M.
Published: July 2010

Groundwater discharge from the Riverine Plains of the southern Murray‐Darling Basin is a major process contributing salt to the Murray River in Australia. In this study, data from an irrigated 60 000 ha catchment in the Riverine Plains were analysed to understand groundwater discharge into deeply incised drains, the process dominating salt mobilization from the catchment. We applied three integrated methodologies: classification and regression trees (CART), conceptual modelling and artificial neural networks (ANNs) to a comprehensive, spatially lumped, monthly data set from July 1975 to December 2004. Using CART analysis, it was shown that rainfall was the most important variable consistently explaining the salt load patterns at the catchment outlet. Using the conceptual model representing spatially lumped groundwater discharge into deeply incised drains, we demonstrated that salt mobilization from the study catchment can be well represented by a rainfall contribution, influenced by the hydraulic head in the deep regional aquifer and potential evapotranspiration. Using ANNs, it was confirmed that rainfall had a much higher impact on salt loads at the catchment outlet than irrigation water use. All these results demonstrate that under conditions similar to those experienced from 1975 to 2004, it is rainfall rather than irrigation water use that governs salt mobilization from the study catchment. Management of salt mobilization from irrigated catchments has traditionally focussed on the improvement of irrigation practices but it could be equally important to further understand the scope for management to control groundwater discharge in these irrigation areas. Copyright © 2010 John Wiley & Sons, Ltd.
Assessing the results of scenarios of climate and land use changes on the hydrology of an Italian catchment: modelling study
Authors: D'Agostino Daniela R. , Trisorio Liuzzi Giuliana , Lamaddalena Nicola , Ragab Ragab
Published: July 2010

Hydrological models are recognized as valid scientific tools to study water quantity and quality and provide support for the integrated management and planning of water resources at different scales. In common with many catchments in the Mediterranean, the study catchment has many problems such as the increasing gap between water demand and supply, water quality deterioration, scarcity of available data, lack of measurements and specific information. The application of hydrological models to investigate hydrological processes in this type of catchments is of particular relevance for water planning strategies to address the possible impact of climate and land use changes on water resources.

The distributed catchment scale model (DiCaSM) was selected to study the impact of climate and land use changes on the hydrological cycle and the water balance components in the Apulia region, southern Italy, specifically in the Candelaro catchment (1780 km2). The results obtained from this investigation proved the ability of DiCaSM to quantify the different components of the catchment water balance and to successfully simulate the stream flows. In addition, the model was run with the climate change scenarios for southern Italy, i.e. reduced winter rainfall by 5–10%, reduced summer rainfall by 15–20%, winter temperature rise by 1·25–1·5 °C and summer temperature rise by 1·5–1·75 °C. The results indicated that by 2050, groundwater recharge in the Candelaro catchment would decrease by 21–31% and stream flows by 16–23%. The model results also showed that the projected durum wheat yield up to 2050 is likely to decrease between 2·2% and 10·4% due to the future reduction in rainfall and increase in temperature.

In the current study, the reliability of the DiCaSM was assessed when applied to the Candelaro catchment; those parameters that may cause uncertainty in model output were investigated using a generalized likelihood uncertainty estimation (GLUE) methodology. The results showed that DiCaSM provided a small level of uncertainty and subsequently, a higher confidence level. Copyright © 2010 John Wiley & Sons, Ltd.
New challenges in integrated water quality modelling
Authors: Rode Michael , Arhonditsis George , Balin Daniela , Kebede Tesfaye , Krysanova Valentina , van Griensven Ann , van der Zee Sjoerd E. A. T. M.
Published: July 2010

There is an increasing pressure for development of integrated water quality models that effectively couple catchment and in‐stream biogeochemical processes. This need stems from increasing legislative requirements and emerging demands related to contemporary climate and land use changes. Modelling water quality and nutrient transport is challenging due a number of serious constraints associated with the input data as well as existing knowledge gaps related to the mathematical description of landscape and in‐stream biogeochemical processes. The present paper summarizes the discussions held during the workshop on ‘Integrated water quality modelling: future demands and perspectives’ (Magdeburg, Germany, 23–24 June 2008). Our primary focus is placed on the current limitations and future challenges in water quality modelling. In particular, we evaluate the current state of integrated water quality modelling, we highlight major research needs to assess and reduce model uncertainties, and we examine opportunities to enhance model predictive capacity. To better account for the need of upscaling process knowledge, we advocate the adoption of combined process‐oriented field and modelling studies at representative sites. In‐stream nutrient metabolism investigations at the entire range of stream and river scales will enable the improvement of the mathematical representation of these processes and therefore the articulation level of coupled watershed‐receiving waterbody models. Keeping the complexity of integrated water quality models in mind, the development of novel uncertainty analysis techniques for rigorous assessing parameter identification and model credibility is essential. In this regard, we recommend the use of Bayesian calibration frameworks that explicitly accommodate measurement errors, parameter uncertainties, and model structure errors. The Bayesian inference can be used to quantify the information the data contain about model inputs, to offer insights into the covariance structure among parameter estimates, to obtain predictions along with credible intervals for model outputs, and to effectively address the ‘change of support’ problems. Copyright © 2010 John Wiley & Sons, Ltd.
Estimating reference evapotranspiration using numerical weather modelling
Authors: Ishak Asnor Muizan , Bray Michaela , Remesan Renji , Han Dawei
Published: July 2010

Evapotranspiration is an important hydrological process and its estimation usually needs measurements of many weather variables such as atmospheric pressure, wind speed, air temperature, net radiation and relative humidity. Those weather variables are not easily obtainable from in situ measurements in practical water resources projects. This study explored a potential application of downscaled global reanalysis weather data using mesoscale modelling system 5 (MM5). The MM5 is able to downscale the global data down to much finer resolutions in space and time for use in hydrological investigations. In this study, the ERA‐40 reanalysis data are downscaled to the Brue catchment in southwest England. The results are compared with the observation data. Among the studied weather variables, atmospheric pressure could be derived very accurately with less than 0·2% error. On the other hand, the error in wind speed is about 200–400%. The errors in other weather variables are air temperature (<10%), relative humidity (5–21%) and net radiation (4–23%). The downscaling process generally improves the data quality (except wind speed) and provides higher data resolution in comparison with the original reanalysis data. The evapotranspiration values estimated from the downscaled data are significantly overestimated across all the seasons (27–46%) based on the FAO Penman–Monteith equation. The dominant weather variables are net radiation (during the warm period) and relative humidity (during the cold period). There are clear patterns among some weather variables and they could be used to correct the biases in the downscaled data from either short‐term in situ measurements or through regionalization from surrounding weather stations. Artificial intelligence tools could be used to map the downscaled data directly into evapotranspiration or even river runoff if rainfall data are available. This study provides hydrologists with valuable information on downscaled weather variables and further exploration of this potentially valuable data source by the hydrological community should be encouraged. Copyright © 2010 John Wiley & Sons, Ltd.
Identification of rural land management signals in runoff response
Authors: McIntyre Neil , Marshall Miles
Published: July 2010

Rural land management signals in catchment‐scale runoff have proven difficult to identify in general. The Pontbren experimental catchment in upland Wales, UK, provides a new data set with which to address this challenge. This data set includes more than 4 years of data from six tipping bucket rainfall gauges and eight stream flow gauges representing different land management regimes at different scales. Data‐based mechanistic rainfall–runoff models were fitted to this data set using the CAPTAIN toolbox. The spatial and temporal variabilities of model parameters were identified and interpreted where possible. The analysis highlighted a dependency between the modelled residence time and the presence of agriculturally improved grassland, which produced a flashier response than grassland in a more natural condition. Another factor found to strongly affect the spatial variability of runoff response was the presence of lakes, while catchment area had a less pronounced effect, and the influence of trees, steepness and soil type could not be identified. Some time variability of response was observed but this was not consistent across the catchment and could not easily be interpreted. Copyright © 2010 John Wiley & Sons, Ltd.
The effect of urbanization on stream hydrology in hillslope watersheds in central Texas
Authors: Sung Chan Yong , Li Ming‐Han
Published: July 2010

This study examined the effect of urbanization on stream hydrology in hillslope watersheds. Ten streams (seven in hillslope and three in gentle slope watersheds) around Austin, Texas were selected for analysis. For each stream, we compared parameters of transfer function (TF) models estimated from daily rainfall and streamflow data collected in two study periods (October 1988–September 1992 and October 2004–September 2008) representing different degrees of watershed urbanization. As expected, the streams became more intermittent as the watersheds were more urbanized in all the study streams. However, the effect of urbanization on peakflow differs between hillslope and gentle slope watersheds. After watershed urbanization, peakflow increased in gentle slope watersheds, but decreased in hillslope watersheds. Based on the results of the TF models, we found that urbanization made stream not flashier but drier in hillslope watersheds. Overpumpage of aquifer has been recognized as a problem that leads to the stream dryness in the study area. However, the overpumpage alone cannot explain the differences in hydrological changes between the two types of watersheds. We attributed the reduced peakflow and stream dryness in the hillslope watersheds to land grading for construction forming stair‐stepped or terraced landscape. Compared with natural hillslope, a stair‐stepped landscape could infiltrate more stormwater by slowing down surface runoff on tread portions of the stair. Our findings suggest that a watershed management scheme should take into account local hydrogeologic conditions to mitigate the stream dryness resulting from urbanization in hillslope watersheds. Copyright © 2010 John Wiley & Sons, Ltd.
A fuzzy‐based simulation method for modelling hydrological processes under uncertainty
Authors: Huang Y. , Chen X. , Li Y. P. , Huang G. H. , Liu T.
Published: July 2010

In this study, a fuzzy‐based simulation method (FBSM) is developed for modelling hydrological processes associated with vague information through coupling fuzzy vertex analysis technique with distributed hydrological model. The FBSM can handle uncertainties existed as fuzzy sets in the hydrological modelling systems, and solutions under an associated number of α‐cut levels can be generated by solving 2n deterministic models. The lower reach of the Tarim River Basin in China is selected as a study case for demonstrating applicability of the proposed method. The developed model is calibrated and validated against observed groundwater elevation for four wells during the period 2000–2001, and generally performed acceptable for model Nash–Sutcliffe coefficient (R2) and correlation coefficient (R). The R2 is approximately over 0·65 and the correlation coefficient is higher than 0·90. Based on the technique of fuzzy simulation, the uncertainties of two parameters (KH and LC) are reflected under different α‐cut levels. The results indicate that, under a lower degree of plausibility, the interval between the lower and upper bounds of the groundwater elevation is wider; conversely, a higher degree of plausibility would lead to a narrow interval. The main effect of KH is more significant than the effect of LC at most well sites. The proposed method is useful for studying hydrological processes within a system containing multiple factors with uncertainties and providing support for identifying proper water resources management strategies. Copyright © 2010 John Wiley & Sons, Ltd.
Direct gaze may modulate face recognition in newborns
Authors: Rigato Silvia , Menon Enrica , Johnson Mark H. , Faraguna Dino , Farroni Teresa
Published: July 2010

Faces are important for non‐verbal communication in daily life, and eye gaze direction provides important information for adult–infant interaction. Four‐month‐old infants and adults better recognize faces when accompanied with direct gaze, suggesting a special status of ‘eye contact’. Whether mutual gaze plays a role in face recognition from birth, or whether it requires expertise, is investigated in this paper. We conducted a between subjects design, for a total of four experiments, two involving habituation (1a, 1b) and two involving preference tests (2a, 2b), to investigate newborns' ability to recognize faces when gaze direction is manipulated. We predicted that a face accompanied with direct gaze would be better recognized by newborns. In contrast, we expected no evidence of identity recognition when newborns were familiarized with a face with averted gaze. According with our expectations, newborns were able to recognize a face identity when previously familiarized with direct gaze, but not with averted gaze. However, this effect was face identity‐specific. Overall, our results suggest that direct gaze can modulate face processing and affects preferences and face identity learning in newborns. Copyright © 2010 John Wiley & Sons, Ltd.
Birth characteristics and Wilms tumors in children in the Nordic countries: A register‐based case–control study
Authors: Schüz Joachim , Schmidt Lisbeth Samsø , Kogner Per , Lähteenmäki Päivi M. , Pal Niklas , Stokland Tore , Schmiegelow Kjeld
Published: July 2010

Little is known about causes of Wilms tumor. Because of the young age at diagnosis, several studies have looked at various birth characteristics. We conducted a registry‐based case–control study involving 690 cases of Wilms tumor aged 0–14 years, occurring in Denmark, Finland, Norway or Sweden during 1985–2006, individually matched to five controls drawn randomly from the Nordic childhood population. Information on birth characteristics was obtained from the population‐based medical birth registries. We estimated odds ratios (ORs) and 95% confidence intervals (CIs) using conditional logistic regression analysis. We observed a distinct association between Wilms tumor and high birth weight (≥4 kg) for girls (OR 1.97, CI 1.50–2.59) but not for boys (1.04, 0.78–1.38); overall, the OR was 1.43 (1.17–1.74). Among girls, risk increased by 28% (15–42%) per 500 g increase in birth weight. Large‐for‐gestational age girls also had a higher risk (2.48, 1.51–4.05), whereas no effect was seen for boys (1.12, 0.60–2.07). An association was seen with Apgar score at 5 min < 7 for both sexes combined (5.13, 2.55–10.3). ORs close to unity were seen for parental age and birth order. In our large‐scale, registry‐based study, we confirmed earlier observations of an association between high birth weight and risk of Wilms tumor, but we found an effect only in girls. The higher risk of infants with low Apgar score might reflect hypoxia causing cell damage, adverse side effects of neonatal treatment or reverse causation as low Apgar score might indicate the presence of a tumor.
Plasminogen activators in human gastric cancers: Correlation with DNA ploidy and immunohistochemical staining
Authors: Takai Souichirou , Yamamura Manabu , Tanaka Kanji , Kawanishi Hiroshi , Tsuji Masazumi , Nakane Yasushi , Hioki Koshirou , Yamamoto Masakatsu
Published: July 2010

Plasminogen activator activity was investigated in extracts of 42 surgically removed gastric carcinomas. The mean levels of total plasminogen activator (total‐PA) and urokinase‐type plasminogen activator (u‐PA) activities in the gastric carcinomas were significantly higher than those in the background normal tissues (p < 0.001). On electrophoresis, gastric cancers were found to contain u‐PA as the predominant PA, this being confirmed using zymography by direct inhibition with anti‐urokinase antibody. Assessment of the relationship between PA activity and biological behavior of gastric cancer revealed total‐PA and u‐PA levels to be significantly higher in differentiated than in undifferentiated tumors (p < 0.001), and in aneuploid than in diploid ones (p < 0.01). Immunohistochemical staining showed that the proportion of u‐PA‐positive cancer cells in the carcinoma tissues also correlated with activity as measured by the azocaseinolytic method. These findings suggest that the study of PA contents in gastric cancer, combined with a nuclear DNA ploidy and immunohistochemical analysis, might be useful for understanding the biological characteristics of the tumor.
Dietary and serum carotenoids and cervical intraepithelial neoplasia
Authors: Van Eenwyk Juliet , Davis Faith G. , Bowen Phyllis E.
Published: July 2010

A case‐control study examined the association between cervical intra‐epithelial neoplasia (CIN) and serum and dietary alpha‐carotene, beta‐carotene, cryptoxanthin, lutein, and lycopene. Cases (n = 102) had biopsy confirmed CIN I, II or III. Controls matched for age, ethnic origin and clinic (n = 102) had normal Pap smears. Participants completed health history and food frequency questionnaires. Fasting venous blood samples were assayed for serum carotenoids. Multivariable conditional logistic regression analyses yielded odds ratios and 95% confidence intervals (CIs) for those in quartiles 3, 2, and I (lowest) compared to quartile 4 (highest) of serum lycopene of 3.5 (I.I‐II.5), 4.7 (1.2–17.7) and 3.8 (1.1–12.4), respectively. Similar analyses yielded adjusted odds ratios (OR, s) and 95% CIs of 4.6 (1.1–19.7), 5.8 (1.6–21.3) and 5.4 (1.3–23.3) for dietary intake of lycopene. The findings for lycopene‐rich foods (tomatoes) were consistent with this result. CIN was not associated with the lutein. Findings for alpha‐carotene, beta‐carotene and cryptoxanthin were ambiguous. Quartile of vitamin C intake was also inversely associated with CIN with OR, s and 95% CIs of 3.7 (0.9–14.6), 4.1 (1.0–17.2), and 6.4 (1.4–30.0) for those in quartiles 3, 2, and I compared to quartile 4.
Establishment and characterization of a human melanoma cell line (MV3) which is highly metastatic in nude mice
Authors: van Muijen Goos N. P. , Jansen Kees F. J. , Cornelissen Ine M. H. A. , Smeets Dominique F. C. M. , Beck Johan L. M. , Ruiter Dirk J.
Published: July 2010

To select human melanoma cells that are highly tumorigenic and metastatic in nude mice we have implanted fragments of a fresh human melanoma metastasis subcutaneously (s.c.) into a nude mouse. After 3 passages in nude mice, part of the xenograft was cultured and a new melanoma cell line, MV3, was established. After intravenous (i.v) inoculation of 2 × 104 MV3 cells, 95% of the nude mice (n = 20) developed lung colonies within 6 weeks. S.c. inoculation of 2 × 104 MV3 cells resulted in 95% tumor take, while 90% of the mice (n = 20) showed spontaneous metastases in the lungs within 7 weeks. Histological and immunohistological features of the original tumor of the patient were largely retained in the tumors of the mice and in the cell line in vitro. As shown by Aldan blue staining, MV3 cells contain large quantities of gly‐cosaminoglycans (GAGs) and/or proteoglycanes (PGs), both in vivo and in vitro. The cells showed a marked expression of transferrin receptor, ICAM‐I, EGF‐receptor, and VLA‐2 inte‐grin. As only few human melanoma cell lines are available that frequently show metastasis in nude mice, the highly metastatic MV3 cell line represents a useful tool for studying the expression and regulation of molecules on human melanoma cells involved in the process of metastasis.
Role of prolactin in growth of the rat mammary tumor MTW9
Authors: Platica Micsunica , Doody Jacqueline , Mandeli John P. , Hollander Vincent P.
Published: July 2010

The growth of MTW9 mammary tumors exhibits different degrees of responsiveness to ovariectomy, ranging from sensitivity to resistance. This range of response is a function of time elapsing from tumor inoculation until performance of ovariectomy provided that prolactin (PRL) level is kept continuously high. In vivo studies showed that the MTW9 tumors developed by chronic administration of spiramide were sensitive to ovariectomy by 60 days, but they became resistant to ovariectomy by 100 days. However, when spiramide treatment was discontinued after tumor appearance, the tumors were still sensitive to ovariectomy by 100 days. Chromatofo‐cusing (CF) profile of cytosolic estrogen receptors (ER) correlated with the responsiveness to ovariectomy. A 2‐peak profile for tumors sensitive to ovariectomy, and only a one‐peak profile for tumors resistant to ovariectomy, were seen. Although the prolactin level in rats bearing the tumors was higher than in the normal rats, no correlation between the PRL level and the change in CF profile of ER over time was seen. Also, these changes could not be correlated with the tumor size. In vitro studies showed that incubation of cytosolic ER from a sensitive tumor (2 peaks) with PRL led to a CF profile with only one peak, characteristic of a resistant tumor. Leupeptin, molybdate and phenylmethylsulfonylfluoride (PMSF) could not prevent this transition. The effect was not reproduced by incubation with growth hormone or progesterone. Our data suggest that PRL, either directly or through intermediates, may play a role in changing the response to hormonal therapy of the mammary tumor MTW9.
Transformation of a mammary epithelial cell line by the v‐raf and v‐mos oncogenes
Authors: Scully Jackie Leach , Edwards Paul A. W.
Published: July 2010

Defective retroviruses were used to investigate the effects of the oncogenes v‐raf and v‐mos on the behaviour of mammary epithelial cells. Cultures of the mammary epithelial cell lines #43 and NMuMG infected with either virus showed obvious areas of overgrowing cells, which were not seen when cells were infected with control viruses not containing an oncogene. Several clonal cell lines were derived from the areas of overgrowth on #43 cells. Most of these were tumorigenic on subcutaneous inoculation. In culture, several of the cloned lines showed marked morphological abnormalities, had altered rates of growth and saturation densities, and were able to clone in soft agar. Unexpectedly, one raf‐containing and one mos‐containing line grew more slowly in culture than did control or uninfected cells. Other lines showed only some of these changes. In the mos‐containing lines the level of viral transcript corresponded approximately to the extent of transformation, whereas the raf‐containing lines showed no such correlation.
Non—MHC—restricted target—cell lysis by a CD4−CD− TCRαβ T—cell line, as well as by TCR4gMδ T—cell lines, results from lymphokine—activated killing
Authors: Maziarz Richard T. , Groh Veronika , Prendergast Margaret , Fabbi Marina , Strominger Jack L. , Burakoff Steven J.
Published: July 2010

A long—term CD4— CD8—TCR αβ human T—cell line, as well as similar CD4— CD8— TCR γδ T—cell lines for comparison, were generated from various tissues by negative selection using anti—CD4 and anti—CD8 monoclonal antibodies (MAbs) followed by positive selection with specific anti—TCR MAb and then repeated in vitro stimulation with interleukin—enriched media and lectin. These cell lines all demonstrated non—MHC—restricted cytolysis on a variety of human tumor cell lines. However, removal of lymphokines from the culture media for 24 hr abrogated most of the non—MHC—restricted target—cell lysis without affecting TCR αβ or TCR γδ cell viability or TCR function as determined by antibody—triggered redirected target—cell lysis. Subsequent re—exposure to lymphokines reconstituted non—MHC—restricted cytolysis by these cell lines. Thus, much of the non—specific, non—MHC—restricted cytolytic activity generated by CD4—CD8—TCRαβ or TCRγδ cells is secondary to lymphokine—activated killing (LAK) activity. These cells have potent LAK activity and may be prominent in LAK—cell populations. In addition, after lymphokine deprivation, both CD4—CD8—TCRαβ and TCRγδ cells showed residual activity against some tumor—cell targets, the nature of which remains to be defined.
Non‐melanoma skin cancer: Ten years of cancer‐registry‐based surveillance
Authors: Kaldor John , Shugg Dace , Young Bill , Dwyer Terence , Wang You‐Gan
Published: July 2010

The Tasmanian Cancer Registry carried out population‐based surveillance of non‐melanoma skin cancer (NMSC) from 1978 to 1987. A total of 8,651 NMSC were recorded in 7,160 individuals, representing an age‐standardized rate of 161/100,000 per year. Ninety‐four percent of cases were based on histological diagnosis. Incidence of basal‐cell carcinoma (BCC) was higher than the incidence of squamous‐cell carcinoma (SCC). The incidence of NMSC was twice as high in men as in women. Incidence increased substantially with age, more markedly for SCC than BCC. For most body sites, BCC was more frequent, but on highly exposed sites such as the backs of hands, lower limbs in women and ears in men, the incidence of SCC was higher. There was an overall increase of 7% per year in the age‐standardized incidence rate of NMSC. The increase was more marked for BCC than for SCC, and was consistent across age groups and both sexes. A first NMSC during the study period was associated with a 12‐fold increase among men and a 15‐fold increase among women in the risk of development of a new NMSC within 5 years, when compared with the NMSC incidence recorded for the population as a whole.
Age‐period‐cohort modelling of large‐bowel‐cancer incidence by anatomic sub‐site and sex in connecticut
Authors: Dubrow Robert , Bernstein Jonine , Holford Theodore R.
Published: July 2010

In order to investigate etiologic distinctions among the anatomic sub‐sites of the large bowel by sex, the relationship between large‐bowel‐cancer incidence and age at diagnosis, time period at diagnosis, and birth cohort was analyzed by anatomic sub‐site and by sex, using data from the Connecticut Tumor Registry. Included in the study were all incident large‐bowel‐cancer cases occurring between 1950 and 1984 among Connecticut residents aged 40 to 79. Cancers of the large bowel were classified into 5 anatomic sub‐sites: Ascending colon (including cecum), transverse colon (including flexures), descending colon, sigmoid colon, and rectum (including rectosigmoid junction, anal canal, and anus). The data were fitted to log‐linear age‐period‐cohort models. For each of the sub‐sites, the age‐period‐cohort patterns for males and females differed. Within each sex, sub‐site groupings with common patterns were indicated. Among males, the age‐period‐cohort patterns for the colon sub‐sites were fairly similar; but the pattern for the rectum differed markedly from that for the colon sub‐sites. There were secondary differences among the colon sub‐sites that pointed to a secondary distinction between the right and the left colons. Among females, the age‐period‐cohort patterns for the left colon sub‐sites and the rectum were fairly similar. The pattern for the transverse colon differed moderately from that of the left colon, and differed substantially from that of the rectum and the ascending colon. The ascending colon differed markedly from each of the other sub‐sites. It is possible that these differences in age‐period‐cohort patterns reflect etiologic distinctions among sub‐site groupings and between the sexes.
Time trends in cancer mortality in Estonia 1965–1989
Authors: Leinsalu Mall , Rahu Mati
Published: July 2010

Mortality rates for cancer of all sites combined and for 12 selected sites or site groups in Estonia from 1965 to 1989 were studied to assess overall progress in controlling cancer. Between 1965–1969 and 1985–1989, age‐standardized mortality (world population) increased by 12.0% among males and decreased by 5.1% among females. The changes in mortality for the age‐groups 20–44, 45–64, and 65 and over were −0.3%, 23.5% and 5.8% among males and 0.9%, −7.0% and −4.4% among females, respectively. In males, the most marked rise in mortality occurred for cancers of the oral cavity and pharynx, intestine and larynx. In females, the most rapid increase was observed for cancers of the lung, oral cavity and pharynx and breast. The decline in stomach cancer and cervical cancer mortality reflects worldwide trends. However, the noticeable increase in mortality rates for most of the sites indicates a need for strong preventive measures, particularly anti‐smoking campaigns. In general, the time trends in mortality from all cancers combined demonstrate that in Estonia, over the last 25 years, no progress against cancer has been achieved.
Rare Ha‐ras1 alleles and predisposition to testicular cancer
Authors: Ryberg David , Haugen Aage , Heimdal Ketil , Børresen Anne‐Lise , Fosså Sophie Dorothea
Published: July 2010

We have examined the restriction‐fragment‐length polymorphism (RFLP) of the VNTR region flanking the Ha‐ras I gene in genomic DNA from 348 testicular cancer patients and 343 healthy controls. When DNA samples were digested with MspI/HpaII, Southern blot analysis revealed 24 and 15 different alleles in the cancer and the control group respectively. The frequency of rare alleles among cases was significantly higher than in controls. Patients with bilateral cancer and patients with unilateral cancer below 20 years had significantly higher incidence of rare alleles than patients with unilateral cancer older than 20 years.
Over‐expression of p53 protein in human laryngeal carcinoma
Authors: Anwar Khurshid , Nakakuki Kazuya , Imai Hanae , Naiki Hironobu , Inuzuka Manabu
Published: July 2010

We examined the expression of tumor‐suppressor protein p53 in a variety of laryngeal carcinomas from 43 patients (25 primary, 13 metastatic and 5 recurrent cases), 13 normal laryngeal tissues and 7 benign laryngeal nodule biopsy specimens, using the polyclonal antibody CM‐1. Previously we have reported a high incidence of ras mutations (51%) and human papillomavirus (HPV) infection (37%) in these laryngeal carcinomas. p53 protein was detected by immunohistochemistry in 65% of laryngeal carcinomas (60% of primary, 69% of metastatic and 80% of recurrent cases). No correlation was found between p53 over‐expression and histological grading of the tumors. None of the specimens from normal larynx and laryngeal nodules revealed any detectable level of this protein. Furthermore, 11 (69%) of 16 HPV‐positive cases and 17 (77%) of 22 cases with ras mutation showed variable grades of p53 expression. Twelve (71%) of 17 laryngeal carcinomas in current study having both p53 over‐expression and ras mutation were moderately or poorly differentiated. Likewise, positivity for these 2 parameters was significantly increased in metastatic tumors (9 of 13 cases, 69%) as compared with primary and recurrent tumors (8 of 30 cases, 27%) (p < 0.01). Our results suggest that multiple factors are involved in this malignancy, and that the simultaneous over‐expression of p53 and the presence of ras mutation may be related to the progression stage of laryngeal carcinoma.
Analysis of epstein‐barr virus infection in nasopharyngeal biopsies from a group at high risk of nasopharyngeal carcinoma
Authors: Sam C. K. , Brooks L. A. , Niedobitek G. , Young L. S. , Rickinson A. B. , Prasad U.
Published: July 2010

Although Epstein‐Barr virus (EBV) is consistently associated with the epithelial malignancy nasopharyngeal carcinoma (NPC), it is not clear to what extent the normal virus carrier state involves infection of nasopharyngeal epithelium. We attempted to examine this question by screening 26 nasopharyngeal punch biopsies from EBV‐carrying Chinese Malaysians who had presented with clinical symptoms possibly indicative of NPC, but in whom histological analysis of an adjacent biopsy had revealed no evidence of tumour. Assays included (i) in situ hybridization with 35S‐labelled riboprobes specific for EBERs (rather than with BamHI W DNA probes which can give false‐positive results); (ii) cDNA amplification across defined splice junctions of the EBNAI and BamHI A transcripts expressed in latently‐infected NPC cells and of the BHRFI lytic‐cycle transcript; and (iii) immunostaining for the immediate early lytic‐cycle protein BZLFI. Of the 26 biopsies examined, all 23 showing normal nasopharyngeal histology were consistently negative for both latent and lytic‐cycle markers. The other 3 cases were all positive for EBNAI and BamHI A transcripts; these RNAs were almost certainly of tumour rather than normal‐cell origin since these particular biopsies were the only ones to reveal localized foci of EBER‐positive NPC cells; such biopsies were again negative for lytic‐cycle markers. We provisionally conclude that EBV infection of the normal nasopharynx is not a regular feature of the virus carrier state and that screening nasopharyngeal biopsies for viral RNA markers of the latent cycle could be useful in NPC diagnosis.
Comparative abilities of athymic nude mice and severe combined immune deficient (SCID) mice to accept transplants of induced rat mammary carcinomas: Enhanced transplantation efficiency of those rat mammary carcinomas that have elevated expression of neu oncogene
Authors: Oakley Cori S. , Welsch Margaret A. , Zhai Yi‐Fan , Welsch Clifford W. , Chang Chia‐Cheng , Gould Michael N.
Published: July 2010

Grafts of primary carcinogen (DMBA)‐induced mammary carcinomas from Sprague‐Dawley rats have a poor transplantation efficiency in athymic nude mice. Further compromising these mice immunologically via whole‐body irradiation and/or splenectomy, or the administration of hormonal growth factors (estrogen and progesterone) to these mice, did not significantly alter transplantation efficiency. Use of strains of mice that are more immune‐impaired than the athymic nude mouse, i.e., the athymic nude‐beige‐XID mouse (T‐cell and LAK‐cell deficient) or mice with severe combined immune deficiency (SCID) (which lack functional T cells and B cells) also failed to improve transplantation efficiency. In contrast, transplantation efficiency was sharply increased when primary neu‐induced rat mammary carcinomas from female Sprague‐Dawley rats were used. These mammary carcinomas, unlike the DMBA‐induced rat mammary carcinomas, have a very high level of expression of neu; transplantation of these tumors to either athymic nude mice or SCID mice was considerably more efficient. Thus, these data provide evidence that enhanced expression of neu confers heightened efficiency in the transplantation of primary rat mammary carcinomas to immune‐deficient mice (athymic‐nude or SCID). Increased neu expression was a greater determinant than more compromised immune states in the transplantation of these rat mammary carcinomas. This biological characteristic of neu expression in mammary carcinomas provides new, additional insight into the importance of this oncogene in mammary tumorigenic processes and may explain, at least in part, the reported inverse relationship between human breast carcinoma neu expression and patient prognosis.
Risk factors for renal‐cell carcinoma in Denmark. III. Role of weight, physical activity and reproductive factors
Authors: Mellemgaard Anders , Engholm Gerda , McLaughlin Joseph K. , Olsen Jorgen H.
Published: July 2010

A population‐based case‐control study of risk factors for renal‐cell carcinoma was conducted in Denmark from 1989 to 1992. A total of 368 histologically verified cases and 396 controls were included. Information on weight, height, physical activity and reproductive factors were collected in a structured interview, along with information on other suspected risk factors. A significant increase in risk was seen for obese women but not obese men. Although there was no clear gradient, the risk was highest among women with a relative weight in the upper 5% (OR 6.1; 95% CI, 2.3 to 16.1). The increased risk was most evident for high relative weight in ages 30 to 50. No association was observed for height or physical activity. Use of amphetamines was associated with increased risk but, because of the close link with obesity, we were unable to provide evidence that amphetamines are an independent risk factor. We found some evidence for an association with reproductive variables, including decreased risk for women with late menarche and first pregnancy and birth. We observed no association with number of pregnancies or age at menopause, or use of estrogen‐containing medication. © 1994 Wiley‐Liss, Inc.
Protoporphyrin biosynthesis in Melanoma B16 cells stimulated by 5‐aminolevulinic acid and chemical inducers: Characterization of photodynamic inactivation
Authors: Schoenfeld N. , Mamet R. , Nordenberg Y. , Shafran M. , Babushkin T. , Malik Z.
Published: July 2010

The stimulation of protoporphyrin (PP) biosynthesis in BI6 melanoma cells in order to facilitate photodynamic cell killing was studied. Biosynthesis and accumulation of PP in the melanoma cells was increased from 8 to 15 pmol/mg protein by the use of dimethyl‐sulfoxide (DMSO), a differentiation‐inducer. Treatment of the cells with the porphyrogenic agent alh/l‐isopropyl‐acetamide (AIA) stimulated an additional PP increase. The most remarkable enhancement of intracellular PP was achieved by the supplementation of 5‐aminolevulinic acid (5‐ALA) to the growth medium following the addition of DMSO and AIA during the induction phase. The intracellular concentration of PP exceeded 21 950 pmol/mg protein following combined stimulation by DMSO/AIA and 5‐ALA. The porphyrins produced in the incubated cells, in serum‐depleted medium, consisted of 95% PP; 88% of it was recovered from the cells and only 7% was excreted into the medium. Photosensitization of the B16 melanoma cells containing high PP concentrations was effective even at low light doses. Potassium (K) efflux was the first measurable sign of cell damage determined by X‐ray microanalysis (XRMA) following fast liquid‐nitrogen fixation. During a I min interval, 70% of cellular K was lost. After 5 min illumination, complete cell destruction was detected by scanning electron microscopy (SEM) and XRMA. The photodam‐aged cells showed influx of Na, CI and Ca ions accompanying the immediate K losses. Ultrastructural cell damage was manifested by disintegration of the outer membrane. Total cell death of B16 melanoma cells was achieved by chemical induction of endogenous PP and photosensitization.
Dipyridamole modulates multidrug resistance and intracellular as well as nuclear levels of doxorubicin in B16 melanoma cells
Authors: Damle Bharat D. , Sridhar Rajagopalan , Desai Pankaj B.
Published: July 2010

Simultaneous occurrence of resistance to many chemothera‐peutic agents, termed multidrug resistance (MDR), is a complex phenotype. MDR occurs due to several reasons, including over‐expression of a 170‐kDa membrane‐bound protein, called P‐glycoprotein (P‐gp), which apparently participates in active drug efflux. Multidrug‐resistant cells also frequently exhibit an altered pattern of intracellular drug distribution, resulting in a reduction in the nuclear level of drugs such as doxorubicin (DOX). In this study, the effect of dipyridamole (DP) on drug resistance and on intracellular as well as nuclear levels of DOX in multidrug‐resistant melanoma cells has been examined. For this purpose, drug‐sensitive murine melanoma cells (B16V) and their multidrug‐resistant variant cells, (B16VDXR; selected for resistance to DOX) which over‐produceP‐gp, were employed. B16VDXR cells were cross‐resistant to several anti‐cancer agents including etoposide (VP‐16) and mitoxantrone (Mitox). DP (10 m̈M) significantly potentiated the cytotoxicity of DOX, VP‐16 and Mitox towards multidrug‐resistant B16VDXR cells but not in parental drug‐sensitive B16V cells. The presence of DP resulted in a 3.7‐fold increase in the total cellular level and a 4.2‐fold increase in the nuclear content of DOX in the resistant cells. Isobologram analysis indicates that DP at several pharmacologically relevant concentrations synergistically potentiates the activity of DOX in B16VDXR cells.
Susceptibility to ultraviolet‐induced corneal sarcomas is highly heritable in a laboratory opossum model
Authors: VandeBerg John L. , Williams‐Blangero Sarah , Hubbard Gene B. , Robinson Edward S.
Published: July 2010

The laboratory opossum, Monodelphis domestiea, develops hyperplasia and neoplasia of the corneal stroma after repeated exposure to low doses of ultraviolet radiation (UVR) (non‐erythemic in skin). We exposed adult animals from genetically diverse families within our colony to determine whether there are any heritable components to the risk of this form of eye cancer. From about 5 months of age, animals were exposed 3 times a week to a dose of about 125 J/m2 of UVB (spectral peak = 302 nm). Thirty‐three sibships (151 individuals) completed at least 30 weeks of the protocol and 137 individuals completed 45 weeks. For genetic analysis, each animal was classified at 30 and 45 weeks as affected with corneal sarcoma or not. Heritabilities were estimated for the dichotomous eye‐tumor trait which was highly heritable at both time points. This eye‐cancer model system is valuable as a source of material for in vitro studies of angiogenesis and neoplastic transformation, for in vivo studies of tumor therapy and prevention, and for further research on the genetic determinants of cancer.
Photochemical crosslinked electrospun collagen nanofibers: Synthesis, characterization and neural stem cell interactions
Authors: Liu Ting , Teng Wai Keng , Chan Barbara P. , Chew Sing Yian
Published: July 2010

Currently available crosslinking methods for electrospun collagen nanofibers do not preserve the fibrous architecture over prolonged periods of time. In addition, electrospinning of collagen often involves solvents that lead to extensive protein denaturation. In this study, we demonstrate the advantage of acetic acid over 1,1,1,3,3,3 hexafluoroisopropanol (HFP) in preventing collagen denaturation. A novel photochemical crosslinking method using rose bengal as the photoinitiator is also introduced. Using circular dichorism analyses, we demonstrate the fraction of collagen helical structure to be significantly greater in acetic acid‐spun fibers than HFP‐spun fibers (28.9 ± 5.9% vs. 12.5 ± 2.0%, p < 0.05). By introducing 0.1% (w/v) rose bengal into collagen fibers and subjecting these scaffolds to laser irradiation at a wavelength of 514 nm for 100 sec, biodegradable crosslinked scaffolds were obtained. Scaffold degradation as evaluated by soaking crosslinked collagen scaffolds in PBS at 37°C, indicated a mass loss of 47.7 ± 7.4% and 68.9 ± 24.7% at day 7 and day 15, respectively. However, these scaffolds retained fibrous architecture for at least 21 days under physiological conditions. Neural stem cell line, C17.2, cultured on crosslinked collagen scaffolds proliferated after 7 days by forming a confluent layer of cells with extensive cellular projections that were indicative of neurite outgrowth. Taken together, these findings support the potential of acetic acid‐electrospun photochemical crosslinked collagen nanofibers for neural tissue engineering. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2010.