bluuebunny/crossref_metadata_2025_split huggingface dataset:
Signal‐transduction pathways in androgen‐dependent and androgen‐independent prostate tumor cells
Authors: Ramsamooj Priya , Jung Mira 
Published: February 2007

AbstractWe have investigated the differential responses of androgen‐dependent prostate tumor cell line LNCaP and androgen‐independent prostate tumor cell line PC‐3 to various effectors at the level of mitogen‐activated protein kinase (MAPK) signal‐transduction intermediates. We have examined the change in protein levels of ras, raf, mek1,2, and erk1,2 in LNCaP and PC‐3 cells following treatment with dihydrotestosterone (DHT), estradiol (E2), ionizing radiation, tumor necrosis factor alpha (TNFα), ZnSO4, and CdSO4, DHT treatment of androgen‐dependent LNCaP cells resulted in an increase in cellular ras protein levels by 1 hour after treatment, whereas ras levels decreased 0.5 hours after DHT treatment of androgen‐independent PC‐3 cells. These data indicate that, in fact, DHT does invoke a differential response in androgen‐dependent compared to androgenindependent prostate tumor cells. E2 treatment resulted in a change in ras levels for LNCaP cells, but not for PC‐3 cells, which is further evidence of a differential response in these prostate tumor cells. Ionizing radiation, TNFα, and CdSO4 treatment showed no effect on signal‐transduction intermediates; however, ZnSO4 treatment of LNCaP cells resulted in an increase in ras protein levels and a decrease in raf‐1 protein levels. No change in ras levels was observed in PC‐3 cells upon ZnSO4 treatment. Our data show few differences in the signal‐transduction intermediates of the MAPK pathway in LNCaP and PC‐3 prostate tumor cells in response to tested stimuli. These results and the observation that cellular mek1,2 and erk1,2 protein levels were constituitively elevated support the hypothesis that MAPK‐independent signal transduction may be occurring in these prostate cells. © 1995 Wiley‐Liss, Inc.
Mini review: Proteases and invasion in human prostate epithelial cell lines: Implications in prostate cancer prevention and intervention
Authors: Webber Mukta M. , Waghray Anuradha , Bello Diana , Rhim Johng S. 
Published: February 2007

AbstractWe propose that, in prostate cancer, serine proteases occupy the apex of the proteolytic cascade and initiate the process of matrix degradation. Subsequently, collagenases are recruited after activation of procollagenases by another serine protease plasmin, which is formed by the activation of plasminogen by urokinase (u‐PA). We show that u‐PA alone can degrade fibronectin but not laminin. Serum free‐conditioned medium (SF‐CM) from DU‐145 human prostatic carcinoma cells can degrade both fibronectin and laminin. Urokinase and gelatinase secretion was compared and correlated with the invasive ability of several human prostatic epithelial cell lines. DU‐145 and LNCaP carcinoma cell lines and the following cell lines developed in our laboratories were used: PWR‐1E (Ad12‐SV40 immortalized, nontumorigenic), RWPE‐1 (HPV‐18 immortalized, nontumorigenic), and RWPE‐2 (HPV‐18 immortalized, Ki‐ras‐transformed, tumorigenic). Secreted urokinase levels were markedly increased in the malignant DU‐145 and RWPE‐2 cells and correlated with their invasive ability in vitro. Secreted gelatinase activity was undetectable in SF‐CM from DU‐145, trace in LNCaP, but detectable in the other three cell lines. The tumorigenic RWPE‐2 cells secrete higher levels of gelatinases than their parent RWPE‐1 cells. all‐trans Retinoic acid (RA) caused a decrease in the extracellular u‐PA and gelatinase activity and invasive ability of DU‐145 and RWPE‐2 cells. Treatment of cultures with RA reduced the ability of SF‐CM to degrade fibronectin and laminin. These results may explain one mechanism by which retinoids inhibit invasion and metastasis. These studies have important translational value in the chemoprevention of prostatic intraepithelial neoplasia (PIN) and intervention in the progression of human prostate cancer. © 1995 Wiley‐Liss, Inc.
Immortalization of human uroepithelial cells by human papillomavirus 16 E6 or E7
Authors: Belair Cassandra D. , Blelloch Robert H. , Reznikoff Catherine A. 
Published: February 2007

AbstractMany different human epithelial cell types have been immortalized by the high‐risk human papillomaviruses (HPV)16 and HPV18. Only a few cell types have been immortalized using either a high‐risk HPV E6 or E7 alone. Here, we report reproducible immortalization of human uroepithelial cells (HUCs) from several normal tissue donors after transformation with either HPV16 E6 or HPV16 E7. To date, this is the only report of a cell type in which both HPV E6 or E7 alone led to immortalization. The five E6‐HUC lines that were generated showed normal pRb levels and almost undetectable p53 levels (attributed to E6 directed ubiquitin degradation), whereas the five E7‐HUC lines showed decreased pRb levels and the stabilized p53 levels that are characteristic of E7‐transformed cells. In general, E7‐HUCs resembled normal HUCs in morphology and growth characteristics, whereas E6‐HUCs resembled HPV16 E6/E7‐transformed HUCs. These findings are consistent with our earlier observations that E7‐HUCs have relatively stable karyotypes, whereas E6‐HUCs show chromosome instability. Because both pRb and p53 alterations occur in a high percentage of clinical bladder cancers, these cell lines may be important tools in studying in vitro the biological significance of pRb and p53 alterations early in the pathogenesis of bladder cancer. © 1995 Wiley‐Liss, Inc.
Radiogenic transformation of human mammary epithelial cells in vitro
Authors: Yang Tracy Chui‐Hsu , Georgy Kerry A. , Tavakoli Azar , Craise Laurie M. , Durante Marco 
Published: February 2007

AbstractCancer induction by space radiations is a major concern for manned space exploration. Accurate assessment of radiation risk at low doses requires basic understanding of mechanism(s) of radiation carcinogenesis. For determining the oncogenic effects of ionizing radiation in human epithelial cells, we transformed a mammary epithelial cell line (185B5), which was immortalized by benzo(a)pyrene, with energetic heavy ions and obtained several transformed clones. These transformed cells showed growth properties on Matrigel similar to human mammary tumor cells. To better understand the mechanisms of radiogenic transformation of human cells, we systematically examined the alterations in chromosomes and cancer genes. Among 16 autosomes examined for translocations, by using fluorescence in situ hybridization (FISH) technique, chromosomes 3, 12, 13, 15, 16, and 18 appeared to be normal in transformed cells. Chromosomes 1, 4, 6, 8, and 17 in transformed cells, however, showed patterns different from those in nontransformed cells. Southern blot analyses indicated no detectable alterations in myc, ras, Rb, or p53 genes. Further studies of chromosome 17 by using in situ hybridization with unique sequence p53 gene probe and a centromere probe showed no loss of p53 gene in transformed cells. Experimental results from cell fusion studies indicated that the transforming gene(s) is recessive. The role of genomic instability and tumor suppressor gene(s) in radiogenic transformation of human breast cells remains to be identified. © 1995 Wiley‐Liss, Inc.
The spatial arrangement of Neritina virginea (Gastropoda: Neritidae) during upstream migration in a split‐channel reach
Authors: Blanco Juan F. , Scatena Frederick N. 
Published: February 2007

AbstractThis paper relates differences in flow hydraulics between a main channel (MC) and a side channel (SC) of a river to patterns of upstream migration by Neritina virginea (Neritidae: Gastropoda), a dominant diadromous snail in streams of Puerto Rico (Greater Antilles). Near‐bed water velocity, snail density and shell size were measured on a weekly basis between August and December 2000 along cross‐sections in a main channel (MC) and an adjacent channel (SC) under a bridge crossing of the Río Mameyes of Northeastern Puerto Rico. Near‐bed velocity and water depth were used to compute Reynolds (Re) and Froude (Fr) numbers, and to classify flows within each channel. During base flow conditions (<2 m3 s−1), flow was chaotic and supercritical (Fr > 1) in the MC, and non‐chaotic and subcritical (Fr < 1) in the SC. Higher mean densities (>100 ind m−2) of relatively small snails (mean ± s.d., 6.3 ± 2.8 mm) were consistently recorded in the MC. Conversely, the SC had lower mean densities (<20 ind m−2) and significantly larger snails (7.6 ± 2.4 mm). Within the MC, migratory groups preferred near‐bed velocities > 0.8 m s−1. Within the SC, they preferred the channel thalweg and depths > 30 cm. The spatial arrangement that was observed between and within the channels may be related to food resources, predation pressure or biomechanics. Characteristics of preferred upstream migration pathways of N. virginea must be accounted when building road crossings in coastal streams with diadromous fauna. Published in 2007 by John Wiley & Sons, Ltd.
Instream flows and the decline of riparian cottonwoods along the Yakima River, Washington, USA
Authors: Braatne Jeffrey H. , Jamieson Robert , Gill Karen M. , Rood Stewart B. 
Published: February 2007

AbstractUnder pre‐settlement conditions the Yakima River in Washington state, USA was characterized by multiple channels, complex aquifers and extensive riparian cottonwood forests. Subsequent implementation of headwater dams to supply irrigation water has altered river and floodplain processes critical to the cottonwoods and associated riparian vegetation. In this study, we analysed hydrology and floodplain forests and especially the dominant black cottonwoods (Populus trichocarpa) along sequential reaches of the Yakima River. Elevations were surveyed and vegetation inventoried along cross‐sectional belt transects, and cottonwood tree ring interpretations investigated historic associations between river hydrology and cottonwood establishment and growth. We analysed hydrographs relative to the apparent episodes of cottonwood recruitment and applied a quantitative model for seedling colonization that required: (1) floods, disturbance flows to produce barren nursery sites, and subsequent flows for seedling (2) establishment and (3) survival. In contrast to earlier conditions, flow patterns after the 1960s have generally been unfavourable for cottonwood recruitment although some cottonwood colonization has occurred in association with physical disturbance from gravel mining. With recent flow regimes, regulated flows along upper reaches maintain the river near bank‐full throughout the growing season, thus inundating suitable seedling recruitment sites. Downstream, irrigation withdrawals reduce the river stage, resulting in seedling establishment at low elevations that are lethally scoured by subsequent high flows. These regulated flow regimes have not hindered growth of established trees, but have reduced the recruitment of cottonwoods, and particularly disfavoured females, thus altering sex ratios and producing skewed cottonwood population age and gender structures. The cottonwood decline has also been associated with other changes in riparian plant community composition, including the encroachment of invasive weeds. Based on this ecohydrologic analysis we discuss flow adjustments that could rejuvenate cottonwood forests along the Yakima River. Copyright © 2007 John Wiley & Sons, Ltd.
Exact one‐sided confidence limits for the difference between two correlated proportions
Authors: Lloyd Chris J. , Moldovan Max V. 
Published: February 2007

AbstractWe construct exact and optimal one‐sided upper and lower confidence bounds for the difference between two probabilities based on matched binary pairs using well‐established optimality theory of Buehler. Starting with five different approximate lower and upper limits, we adjust them to have coverage probability exactly equal to the desired nominal level and then compare the resulting exact limits by their mean size. Exact limits based on the signed root likelihood ratio statistic are preferred and recommended for practical use. Copyright © 2007 John Wiley & Sons, Ltd.
Psychosocial stressors may be strongly associated with suicide attempts
Authors: Baca‐Garcia Enrique , Parra Claudia P. , Perez‐Rodriguez M. Mercedes , Sastre Carmen Diaz , Torres Raquel Reyes , Saiz‐Ruiz Jeronimo , de Leon Jose 
Published: February 2007

AbstractStressful life events are associated with a high proportion of suicide attempts. The aim of this study is to clarify the importance of psychosocial stressors in suicidal behaviour. A total of 258 suicide attempters seen at a general hospital emergency room, and 325 blood donors without suicide/psychiatric disorder history were recruited. Acute and chronic life events were assessed with the St. Paul Ramsey Life Experience Scale and Holmes and Rahe's Social Adjustment Scale, respectively. Lifelong adverse experiences were also assessed. After univariate analyses, the significant variables were introduced in a multivariate analysis (logistic regression). The logistic regression with a dependent variable (attempter versus control status) included psychosocial stressors (partner conflicts [odds ratio (OR) = 33.6] and other interpersonal conflicts [OR = 10.5], modification of life habits [OR = 14.6], and adult physical abuse [OR = 7.1]). Confounding factors with significant ORs were Cluster B traits [OR = 21.2]; and two protective factors, living with a partner [OR = 0.25] and currently working [OR = 0.06]. Psychosocial stressors and Cluster B traits appeared to be strongly associated with suicide attempter status. One limitation of the study is the lack of inclusion of psychiatric controls (psychiatric patients without history of suicide attempts). Another limitation is the difficulty of determining suicide intent. Finally, this study is mainly a replication of prior knowledge of psychosocial stressors, but compares their association strength (OR > 10) with the association strength of prior biological findings (OR = 1–2). Copyright © 2007 John Wiley & Sons, Ltd.
Stress in teaching: a study of occupational stress and its determinants among Italian schoolteachers
Authors: Zurlo Maria Clelia , Pes Daniela , Cooper Cary L. 
Published: February 2007

AbstractThis paper presents the findings of an investigation into stress among Italian teachers conducted by means of the Teacher Stress Questionnaire elaborated by Travers and Cooper. The questionnaire was submitted to 320 southern Italy teachers drawn from a cross‐section of school types. Data were discussed in order to highlight some features of teacher stress peculiar to the Italian sample with respect to those that emerged in the British validation of the questionnaire. In this perspective a comparison was drawn between the intensity and quality of mental ill‐health, the sources of job pressure, the intensity and quality of job satisfaction and the coping strategies adopted by teachers as emerged in this study and in the British study; and between the most predictive dimensions of mental ill‐health highlighted from the present study with respect to the British study. Copyright © 2007 John Wiley & Sons, Ltd.
Spider Silk as an Active Scaffold in the Assembly of Gold Nanoparticles and Application of the Gold–Silk Bioconjugate in Vapor Sensing
Authors: Singh Amit , Hede Shantesh , Sastry Murali 
Published: February 2007

AbstractSpider silk is being viewed with interest by materials scientists due to its excellent resilience and mechanical properties. In this paper we show that spider silk is an excellent scaffold for the one‐step synthesis and assembly of gold nanoparticles. Formation of a gold nanoparticle–spider‐silk bioconjugate material is accomplished by simple reaction of the fibers with aqueous chloroauric acid. The gold nanoparticles thus formed are strongly bound to the spider‐silk fiber surface enabling study of the electrical properties of the nanobioconjugate. Using the well‐known contraction/expansion behavior of the fibers in solvents of varying polarity, we show that exposure of the gold nanoparticle–spider silk bioconjugate to vapors of methanol and chloroform leads to changes in electrical transport through the nanoparticles and thus, the possibility of developing a vapor sensor. The bioconjugate shows excellent response time and cycling efficiency to methanol vapors. The activation energy of electron transport from one gold nanoparticle to another in the nanobiocojugate was determined from temperature‐dependent electron‐transport measurements to be approximately 1.7 eV.
One‐Step Production of Polymeric Microtubes by Co‐electrospinning
Authors: Dror Y. , Salalha W. , Avrahami R. , Zussman E. , Yarin A. L. , Dersch R. , Greiner A. , Wendorff J. H. 
Published: February 2007

AbstractHerein we demonstrate the ability to fabricate polymeric microtubes with an inner diameter of approximately 3 μm through co‐electrospinning of core and shell polymeric solutions. The mechanism by which the core/shell structure is transformed into hollow fibers (microtubes) is primarily based on the evaporation of the core solution through the shell and is described here in detail. Additionally, we present the filling of these microtubes, thus demonstrating their possible use in microfluidics. We also report the incorporation of a protein (green fluorescent protein) within such fibers, which is of interest for sensorics.
Nitrogen‐Doped Tungsten Oxide Nanowires: Low‐Temperature Synthesis on Si, and Electrical, Optical, and Field‐Emission Properties
Authors: Chang Mu‐Tung , Chou Li‐Jen , Chueh Yu‐Lun , Lee Yu‐Chen , Hsieh Chin‐Hua , Chen Chii‐Dong , Lan Yann‐Wen , Chen Lih‐Juann 
Published: February 2007

AbstractVery dense and uniformly distributed nitrogen‐doped tungsten oxide (WO3) nanowires were synthesized successfully on a 4‐inch Si(100) wafer at low temperature. The nanowires were of lengths extending up to 5 μm and diameters ranging from 25 to 35 nm. The highest aspect ratio was estimated to be about 200. An emission peak at 470 nm was found by photoluminescence measurement at room temperature. The suggested growth mechanism of the nanowires is vapor–solid growth, in which gaseous ammonia plays a significant role to reduce the formation temperature. The approach has proved to be a reliable way to produce nitrogen‐doped WO3 nanowires on Si in large quantities. The direct fabrication of WO3‐based nanodevices on Si has been demonstrated.
The impact of turbulence on the effectiveness and efficiency of software development teams in small organizations
Authors: Yilmaz Levent , Phillips Jared 
Published: February 2007

AbstractThis article presents an agent‐based simulation study that explores the effects of team behavior on the efficiency and effectiveness of software development organizations that pursue incremental and iterative processes such as the Rational Unified Process (RUP). The conceptual model underlying the simulation framework is based on the fundamental tenets of organization theory. We present the simulation framework Team‐RUP and use it to examine (a) which team archetypes and associated organizational cooperation mechanisms are effective in incremental and iterative software development strategies such as the RUP and (b) the extent of the impact of turbulence (i.e. change in requirements and employee turnover) on the effectiveness of software development under various team archetypes in small organizations. Using the model, we observe that ‘agility’ via incremental and iterative development strategy is a valid and useful counterbalance to the inevitable change involved in most software projects. Also, we observe that the autonomous and concurrent team archetypes are better suited for large, rather than small, enterprises. We believe that the findings reported in this study form the basis for future hypotheses that will facilitate further empirical studies on software team behavior. Copyright © 2007 John Wiley & Sons, Ltd.
Photodynamic therapy with hematoporphyrin derivative in cancer of the upper gastrointestinal tract
Authors: Hayata Yoshihiro , Kato Harubumi , Okitsu Hiroshi , Kawaguchi Minoru , Konaka Chimori 
Published: February 2007

AbstractAn historical overview is given of the development of photodynamic therapy (PDT) with hematoporphyrin derivative for the treatment of malignant tumors. Results in patients with superficial, and non‐superficial esophageal cancer and with early gastric cancer is described, with case illustrations and follow‐up. Due to the difficulty in early stage diagnoses and in determining all cases of lymph node involvement, mis form of treatment should be employed primarily in inoperable early‐stage cancer, to reduce the extent of resection, or to render previously inoperable cases operable. Combination with other treatment modalities and the effects of PDT on histologically different tumor types, need to be further examined.
Diagnosis and management of cavernous hemangioma of the liver
Authors: Takagi Hiroshi 
Published: February 2007

AbstractCavernous hemangiomas are the most common benign tumors of the liver, which are now seen more often thanks to common use of newer imaging techniques. A review of the literature on cavernous hemangiomas of the liver, including our own experience with 14 cases, provides data as a touchstone for discussion of the incidence, etiology, symptoms, pathology, diagnosis including ultrasound, radionuclide imaging, computed tomography and angiography, management including resection, hepatic artery ligation, radiation and corticosteroid, and the natural history of these lesions. The author concludes that surgical resection of cavernous hemangiomas should be undertaken with due concern for the relation between the severity of symptoms and the operative risks involved.