bluuebunny/crossref_metadata_2025 huggingface dataset:
Circulating Tumor Cells in Perioperative Esophageal Cancer Patients: Quantitative Assay System and Potential Clinical Utility
Authors: Liu Zhian , Jiang Ming , Zhao Jianhua , Ju Huangxian
Published: May 2007

Purpose: To establish a quantitative system for evaluating the role of circulating tumor cells (CTC) in peripheral blood samples in patients who undergo surgery for treatment of esophageal cancer.

Experimental Design: One hundred fifty-five peripheral blood samples from 53 esophageal cancer patients were collected before surgery (B-1), immediately after surgery (B0), and on the 3rd day postoperatively (B+3). Eighty-nine samples from 22 benign patients who underwent thoracotomy and 30 healthy volunteers were obtained as controls. A real-time reverse transcription-PCR quantitative analysis system based on carcinoembryonic antigen (CEA) mRNA gene expression was designed for detection of CTC.

Results: This developed system can detect CEA mRNA-positive cells down to 3 cells per milliliter of peripheral blood. The cells in negative control groups were lower than the detection limit. The medians of 188 [95% confidence interval (95% CI), 155-498], 1513 (95% CI, 660-7,974) and 707 (95% CI, 737-3,005) CEA mRNA-positive cells per mL with the CEA-positive rates of 28.3%, 60.4%, and 42.9% in B-1, B0, and B+3 peripheral blood samples were obtained, respectively. There was statistically significant difference between B-1 and B0 (P = 0.0001) and between B-1 and B+3 (P = 0.0209). Fifty percent of patients with R > 0.4 showed metastasis in 1 year after surgery, whereas the probability was only 14.3% for patients with R < 0.4 (where R is CTC ratio of B+3 to B0, P = 0.043).

Conclusions: Esophageal cancer operation results in tumor cells dissemination and significant increase of CTC in peripheral blood, which is related to the developed metastasis. CTC are helpful for evaluating micrometastasis and have the potential for predicting recurrence in esophageal cancer.
Disruption of Endothelial Cell Interactions with the Novel HU177 Cryptic Collagen Epitope Inhibits Angiogenesis
Authors: Cretu Alexandra , Roth Jennifer M. , Caunt Maresa , Akalu Abebe , Policarpio Desiree , Formenti Silvia , Gagne Paul , Liebes Leonard , Brooks Peter C.
Published: May 2007

Purpose: The importance of cellular communication with the extracellular matrix in regulating cellular invasion is well established. Selective disruption of communication links between cells and the local microenvironment by specifically targeting non-cellular matrix-immobilized cryptic extracellular matrix epitopes may represent an effective new clinical approach to limit tumor-associated angiogenesis. Therefore, we sought to determine whether the HU177 cryptic collagen epitope plays a functional role in regulating angiogenesis in vivo.

Experimental Design: We examined the expression and characterized the HU177 cryptic collagen epitope in vitro and in vivo using immunohistochemistry and ELISA. We examined potential mechanisms by which this cryptic collagen epitope may regulate angiogenesis using in vitro cell adhesion, migration, proliferation, and biochemical assays. Finally, we examined the whether blocking cellular interactions with the HU177 cryptic epitope plays a role in angiogenesis and tumor growth in vivo using the chick embryo model.

Results: The HU177 cryptic epitope was selectively exposed within tumor blood vessel extracellular matrix, whereas little was associated with quiescent vessels. An antibody directed to this cryptic site selectively inhibited endothelial cell adhesion, migration, and proliferation on denatured collagen type IV and induced increased levels of cyclin-dependent kinase inhibitor p27KIP1. Systemic administration of mAb HU177 inhibited cytokine- and tumor-induced angiogenesis in vivo.

Conclusions: We provide evidence for a new functional cryptic regulatory element within collagen IV that regulates tumor angiogenesis. These findings suggest a novel and highly selective approach for regulating angiogenesis by targeting a non-cellular cryptic collagen epitope.
Tissue Factor Expression, Angiogenesis, and Thrombosis in Pancreatic Cancer
Authors: Khorana Alok A. , Ahrendt Steven A. , Ryan Charlotte K. , Francis Charles W. , Hruban Ralph H. , Hu Ying Chuan , Hostetter Galen , Harvey Jennifer , Taubman Mark B.
Published: May 2007

Purpose: Hemostatic activation is common in pancreatic cancer and may be linked to angiogenesis and venous thromboembolism. We investigated expression of tissue factor (TF), the prime initiator of coagulation, in noninvasive and invasive pancreatic neoplasia. We correlated TF expression with vascular endothelial growth factor (VEGF) expression, microvessel density, and venous thromboembolism in resected pancreatic cancer.

Experimental Design: Tissue cores from a tri-institutional retrospective series of patients were used to build tissue microarrays. TF expression was graded semiquantitatively using immunohistochemistry in normal pancreas (n = 10), intraductal papillary mucinous neoplasms (n = 70), pancreatic intraepithelial neoplasia (n = 40), and resected or metastatic pancreatic adenocarcinomas (n = 130).

Results: TF expression was observed in a majority of noninvasive and invasive pancreatic neoplasia, including 77% of pancreatic intraepithelial neoplasias, 91% of intraductal papillary mucinous neoplasms, and 89% of pancreatic cancers, but not in normal pancreas. Sixty-six of 122 resected pancreatic cancers (54%) were found to have high TF expression (defined as grade ≥2, the median score). Carcinomas with high TF expression were more likely to also express VEGF (80% versus 27% with low TF expression, P < 0.0001) and had a higher median MVD (8 versus 5 per tissue core with low TF expression, P = 0.01). Pancreatic cancer patients with high TF expression had a venous thromboembolism rate of 26.3% compared with 4.5% in patients with low TF expression (P = 0.04).

Conclusions: TF expression occurs early in pancreatic neoplastic transformation and is associated with VEGF expression, increased microvessel density, and possibly clinical venous thromboembolism in pancreatic cancer. Prospective studies evaluating the role of TF in pancreatic cancer outcomes are warranted.
Differential Methylation Hybridization Array of Endometrial Cancers Reveals Two Novel Cancer-Specific Methylation Markers
Authors: Zighelboim Israel , Goodfellow Paul J. , Schmidt Amy P. , Walls Ken C. , Mallon Mary Ann , Mutch David G. , Yan Pearlly S. , Huang Tim Hui-Ming , Powell Matthew A.
Published: May 2007

Purpose: To identify novel endometrial cancer-specific methylation markers and to determine their association with clinicopathologic variables and survival outcomes.

Experimental Design: Differential methylation hybridization analysis (DMH) was done for 20 endometrioid endometrial cancers using normal endometrial DNA as a reference control. Combined bisulfite restriction analysis (COBRA) was used to verify methylation of sequences identified by DMH. Bisulfite sequencing was undertaken to further define CpG island methylation and to confirm the reliability of the COBRA. The methylation status of newly identified markers and the MLH1 promoter was evaluated by COBRA in a large series of endometrioid (n = 361) and non-endometrioid uterine cancers (n = 23).

Results: DMH and COBRA identified two CpG islands methylated in tumors but not in normal DNAs: SESN3 (PY2B4) and TITF1 (SC77F6/154). Bisulfite sequencing showed dense methylation of the CpG islands and confirmed the COBRA assays. SESN3 and TITF1 were methylated in 20% and 70% of endometrioid tumors, respectively. MLH1 methylation was seen in 28% of the tumors. TITF1 and SESN3 methylation was highly associated with MLH1 methylation (P < 0.0001). SESN3 and TITF1 were methylated in endometrioid and non-endometrioid tumors, whereas MLH1 methylation was restricted to endometrioid tumors. Methylation at these markers was not associated with survival outcomes.

Conclusions: The 5′ CpG islands for SESN3 and TITF1 are novel cancer-specific methylation markers. Methylation at these loci is strongly associated with aberrant MLH1 methylation in endometrial cancers. SESN3, TITF1 and MLH1 methylation did not predict overall survival or disease-free survival in this large cohort of patients with endometrioid endometrial cancer.
Standardizing Slide-Based Assays in Breast Cancer: Hormone Receptors, HER2, and Sentinel Lymph Nodes
Authors: Ross Jeffrey S. , Symmans W. Fraser , Pusztai Lajos , Hortobagyi Gabriel N.
Published: May 2007

Despite the rapid expansion of novel diagnostics designed to personalize breast cancer care, there remain several significant unmet needs for improving the accuracy and reliability of tests that are already in common daily clinical practice. For example, although immunohistochemistry has been the predominant method for measuring estrogen receptor and progesterone receptor status for over 15 years, this assay remains unstandardized and there is a widespread concern that inaccuracy in immunohistochemistry technique and interpretation is leading to an unacceptably high error rate in determining the true hormone receptor status. Similarly, there is considerable concern that both false-negative and false-positive result rates for testing for HER2 status are unacceptably high in current clinical practice. This commentary considers a variety of factors, including preanalytic conditions and slide-scoring procedures, and other variables that may be contributing to current testing error rates and why there is a great need for the standardization of these biomarker assay procedures to further enable the highest possible quality of care for newly diagnosed breast cancer patients.
Gene Expression Signature Predicts Recurrence in Lung Adenocarcinoma
Authors: Larsen Jill E. , Pavey Sandra J. , Passmore Linda H. , Bowman Rayleen V. , Hayward Nicholas K. , Fong Kwun M.
Published: May 2007

Purpose: Improving outcomes for early-stage lung cancer is a major research focus at present because a significant proportion of stage I patients develop recurrent disease within 5 years of curative-intent lung resection. Within tumor stage groups, conventional prognostic indicators currently fail to predict relapse accurately.

Experimental Design: To identify a gene signature predictive of recurrence in primary lung adenocarcinoma, we analyzed gene expression profiles in a training set of 48 node-negative tumors (stage I-II), comparing tumors from cases who remained disease-free for a minimum of 36 months with those from cases whose disease recurred within 18 months of complete resection.

Results: Cox proportional hazards modeling with leave-one-out cross-validation identified a 54-gene signature capable of predicting risk of recurrence in two independent validation cohorts of 55 adenocarcinomas [log-rank P = 0.039; hazard ratio (HR), 2.2; 95% confidence interval (95% CI), 1.1-4.7] and 40 adenocarcinomas (log-rank P = 0.044; HR, 3.3; 95% CI, 1.4-7.9). Kaplan-Meier log-rank analysis found that predicted poor-outcome groups had significantly shorter survival, and furthermore, the signature predicted outcome independently of conventional indicators of tumor stage and node stage. In a subset of earliest stage adenocarcinomas, generally expected to have good outcome, the signature predicted samples with significantly poorer survival.

Conclusions: We describe a 54-gene signature that predicts the risk of recurrent disease independently of tumor stage and which therefore has potential to refine clinical prognosis for patients undergoing resection for primary adenocarcinoma of the lung.
Inhibition of Poly(ADP-Ribose) Polymerase Enhances Cell Death and Improves Tumor Growth Delay in Irradiated Lung Cancer Models
Authors: Albert Jeffrey M. , Cao Carolyn , Kim Kwang Woon , Willey Christopher D. , Geng Ling , Xiao Dakai , Wang Hong , Sandler Alan , Johnson David H. , Colevas Alexander D. , Low Jennifer , Rothenberg Mace L. , Lu Bo
Published: May 2007

Purpose: Poly(ADP-ribose) polymerase-1 (PARP-1) is the founding member of a family of enzymes that catalyze the addition of ADP-ribose units to proteins that mediate DNA repair pathways. Ionizing radiation induces DNA strand breaks, suggesting that PARP-1 inhibition may sensitize tumor cells to radiation.

Experimental Design: We investigated the combination of PARP-1 inhibition with radiation in lung cancer models. ABT-888, a novel potent PARP-1 inhibitor, was used to explore the effects of PARP-1 inhibition on irradiated tumors and tumor vasculature.

Results: ABT-888 reduced clonogenic survival in H460 lung cancer cells, and inhibited DNA repair as shown by enhanced expression of DNA strand break marker histone γ-H2AX. Both apoptosis and autophagy contributed to the mechanism of increased cell death. Additionally, ABT-888 increased tumor growth delay at well-tolerated doses in murine models. For a 5-fold increase in tumor volume, tumor growth delay was 1 day for ABT-888 alone, 7 days for radiation alone, and 13.5 days for combination treatment. Immunohistochemical staining of tumor sections revealed an increase in terminal deoxyribonucleotide transferase–mediated nick-end labeling apoptotic staining, and a decrease in Ki-67 proliferative staining after combination treatment. Matrigel assay showed a decrease in in vitro endothelial tubule formation with ABT-888/radiation combination treatment, and von Willebrand factor staining of tumor sections revealed decreased vessel formation in vivo, suggesting that this strategy may also target tumor angiogenesis.

Conclusions: We conclude that PARP-1 inhibition shows promise as an effective means of enhancing tumor sensitivity to radiation, and future clinical studies are needed to determine the potential of ABT-888 as a radiation enhancer.
Local Production of Lipoprotein-Associated Phospholipase A
2
and Lysophosphatidylcholine in the Coronary Circulation
Authors: Lavi Shahar , McConnell Joseph P. , Rihal Charanjit S. , Prasad Abhiram , Mathew Verghese , Lerman Lilach O. , Lerman Amir
Published: May 2007

Background—

Lipoprotein-associated phospholipase A
2
(Lp-PLA
2
) is a novel marker and participant in vascular inflammation. Inflammation also is associated with coronary atherosclerosis. We tested the hypothesis that local coronary production of Lp-PLA
2
is enhanced in patients with early coronary atherosclerosis and associated with local endothelial function.

Methods and Results—

Coronary angiography, blood flow, flow reserve, endothelial function assessment, and intravascular ultrasound with volumetric analysis were performed in 15 patients with mild coronary atherosclerosis and in 15 control subjects. Plasma samples were collected simultaneously from the left main coronary artery and coronary sinus for measurement of Lp-PLA
2
, lysophosphatidylcholine (a product of Lp-PLA
2
), and C-reactive protein. Hemodynamic parameters and cholesterol were similar in both groups. Arterial Lp-PLA
2
levels were similar in patients and control subjects: 225 ng/mL (interquartile range [IQR], 196 to 273 ng/mL) versus 221 ng/mL (IQR, 177 to 294 ng/mL). Lp-PLA
2
net production in the coronary circulation was higher in patients compared with control subjects: 519 ng/min (IQR, 198 to 1276 ng/min) versus −529 ng/min (IQR, −872 to −79 ng/min;
P
=0.001) and correlated with percent atheroma volume (
r
s
=0.37,
P
=0.04). Net production of lysophosphatidylcholine was higher in patients compared with control subjects: 199 ng/min (IQR, −592 to 470 ng/min) versus −505 ng/min (IQR, −1119 to 0 ng/min;
P
=0.03) and correlated with coronary endothelial dysfunction (
r
s
=0.5,
P
=0.005). C-reactive protein was not significantly different between the groups.

Conclusions—

Early coronary atherosclerosis in humans is characterized by local production of Lp-PLA
2
. Local coronary production of lysophosphatidylcholine, the active product of Lp-PLA
2
, is associated with endothelial dysfunction. These results support the role for Lp-PLA
2
in the mechanism of regional vascular inflammation and atherosclerosis in humans.
Validation of Renal Oxidative Metabolism Measurement by Positron-Emission Tomography
Authors: Juillard Laurent , Lemoine Sandrine , Janier Marc F. , Barthez Paul Y. , Bonnefoi Frédéric , Laville Maurice
Published: May 2007

Either in research or in clinical practice, the exploration of renal oxidative metabolism is limited by the lack of noninvasive measurement. Positron-emission tomography using carbon-11 acetate may estimate tissue oxidative metabolism by measuring acetate turnover in the Krebs cycle. Although extensively studied in cardiology, this method has never been validated for renal oxidative metabolism measurement. The aim of this study is the validation of acetate turnover compared with the invasive renal oxygen consumption measurement. Renal oxygen consumption and tubular sodium reabsorption were measured invasively in 10 anesthetized pigs. Simultaneously, acetate turnover was estimated by the clearance of carbon-11 acetate in the renal cortex, after a 166-MBq injection of carbon-11 acetate. Renal oxidative metabolism was measured under various conditions induced by mechanical and pharmacological interventions. Renal oxygen consumption and acetate turnover varied on a wide range from 0.05 to 0.29 mmol min
−1
(>5-fold) and from 0.025 to 0.188 minutes
−1
(>7-fold), respectively. Acetate turnover was very significantly correlated with renal oxygen consumption (
P
<0.0001;
R
=0.82) and tubular sodium reabsorption (
P
=0.001;
R
=0.67). This study demonstrates that acetate turnover measures renal oxidative metabolism noninvasively and quantitatively, consistent with changes in tubular sodium reabsorption. This method may be applied to assess oxidative metabolism in animal models and in humans.
Prevention of Stroke and Myocardial Infarction by Amlodipine and Angiotensin Receptor Blockers
Authors: Wang Ji-Guang , Li Yan , Franklin Stanley S. , Safar Michel
Published: May 2007

In the present quantitative overview of outcome trials, we investigated the efficacy of amlodipine or angiotensin receptor blockers in the prevention of stroke and myocardial infarction in patients with hypertension, coronary artery disease, or diabetic nephropathy. The analysis included 12 trials of 94 338 patients. The analysis of trials involving an amlodipine group showed that amlodipine provided more protection against stroke and myocardial infarction than other antihypertensive drugs, including angiotensin receptor blockers (−19%,
P
<0.0001 and −7%,
P
=0.03) and placebo (−37%,
P
=0.06 and −29%,
P
=0.04). The analysis of trials involving an angiotensin receptor blocker group showed contrasting results between trials versus amlodipine and trials versus other antihypertensive drugs for stroke (+19% versus −25%;
P
<0.0001) and myocardial infarction (+21% versus +1%;
P
=0.03). The results of 3 trials comparing an angiotensin receptor blocker with placebo were neutral (
P
≥0.14). The within-trial between-group difference in achieved systolic pressure ranged from −1.1 to +4.7 mm Hg for trials involving an amlodipine group and from −2.8 to +4.0 mm Hg for trials involving an angiotensin receptor blocker group. The metaregression analysis correlating odds ratios with blood pressure differences showed a negative relationship (regression coefficients: −3% to −8%), which reached statistical significance (regression coefficient: −6%;
P
=0.01) for stroke in trials involving an amlodipine group. In conclusion, blood pressure differences largely accounted for cardiovascular outcome.
Baroreflex Sensitivity Inversely Correlates With Ambulatory Blood Pressure in Healthy Normotensive Humans
Authors: Hesse Christiane , Charkoudian Nisha , Liu Zhong , Joyner Michael J. , Eisenach John H.
Published: May 2007

Patients with hypertension have a blunted sensitivity of baroreflex control of heart period. In these patients, baroreflex sensitivity is positively related to heart rate variability and inversely related to blood pressure variability. We hypothesized that this relationship would also be evident in healthy normotensive subjects and that individuals with higher baroreflex sensitivity would have lower ambulatory 24-hour blood pressure. Twenty-four-hour ambulatory blood pressure and heart rate were recorded in 50 healthy, normotensive, nonobese individuals (31 women and 19 men). The baroreflex was assessed using sequential bolus administration of sodium nitroprusside and phenylephrine, and baroreflex sensitivity was calculated as the slope of the relation between systolic blood pressure and R-R interval during the resulting blood pressure transients. Baroreflex sensitivity was inversely correlated to 24-hour average mean arterial pressure (
R
=0.49;
P
<0.001) and positively related to daytime heart rate variability (
R
=0.33;
P
=0.02). In contrast, no relationship was found between baroreflex sensitivity and 24-hour heart rate or blood pressure variabilities. We conclude that the relationship between baroreflex sensitivity and daytime heart rate variability was similar to that reported previously in hypertensive subjects. Furthermore, the inverse relation between baroreflex sensitivity and mean arterial pressure supports the idea that the baroreflex may exert longer-term effects on blood pressure than thought previously.
The Two “Logics” of Community Development: Neighborhoods, Markets, and Community Development Corporations
Authors: Kirkpatrick L. Owen
Published: May 2007

Two Community Development Corporations (CDCs) in Oakland, California, anchor the following analysis. These legally homogenous organizations have implemented similar “low-income” redevelopment projects widely hailed as representing a single successful blueprint for urban revitalization. Despite their similarities, however, these entities have produced starkly different socio-economic outcomes—a phenomenon traced to the CDCs' divergent internal structures and the contrasting external contexts of their development activities. These variations generated competing “logics” of redevelopment. On one hand, we find a CDC dominated by market-oriented interests and the economic logic of exchange-values, while on the other, we find a CDC dominated by community-oriented interests and the social logic of neighborhood use-values.
Automatic and Self-Reported Attitudes in Romantic Relationships
Authors: Scinta Anthony , Gable Shelly L.
Published: May 2007

Two studies used response latency measures to assess automatic attitudes that individuals are unwilling or unable to reveal about their partners. In Study 1, participants (n = 51) in dating relationships completed two response latency measures (Time 1) and several relationship self-reports (Times 1 and 2). Participants who faced high barriers to exiting (BTE) their relationship generally showed a negative association between their relationship self-reports and automatic attitudes, and there was some evidence that automatic attitudes at Time 1 predicted relationship satisfaction at Time 2. Study 2 (n = 41 couples) replicated the BTE finding and showed that image-based response latency measures may assess automatic attitudes more effectively than word-based measures. A negative correlation between self-reported and automatic attitudes among high-BTE participants suggests that they may overreport relationship positivity to quell feelings of doubt about a relationship they cannot feasibly dissolve.
Deficiencies in European company information
Authors: Green Louise
Published: May 2007

Explains why there is currently no Companies House for Europe and describes the pan-European company information solution developed in a standardized format as an alternative by Bureau van Dijk. Outlines the cultural differences between company accounts filing regimes in different European countries, distinguishing between the Anglo-Saxon countries' approach of providing information for shareholders and the Continental approach of providing information for taxation and statistical purposes. Compares accounting practices and filing rules in a number of individual countries, indicating how their situations are changing. Gives details of the additional information that Bureau van Dijk information providers source, including industry classification, merger & acquisition and ownership data, and outlines the collection process. Emphasizes that users need to distinguish between what is missing and what is simply unavailable.
Development and Validation of a Response Bias Scale (RBS) for the MMPI-2
Authors: Gervais Roger O. , Ben-Porath Yossef S. , Wygant Dustin B. , Green Paul
Published: May 2007

This study describes the development of a Minnesota Multiphasic Personality Inventory (MMPI-2) scale designed to detect negative response bias in forensic neuropsychological or disability assessment settings. The Response Bias Scale (RBS) consists of 28 MMPI-2 items that discriminated between persons who passed or failed the Word Memory Test (WMT), Computerized Assessment of Response Bias (CARB), and/or Test of Memory Malingering (TOMM) in a sample of 1,212 nonhead-injury disability claimants. Incremental validity of the RBS was evaluated by comparing its ability to detect poor performance on four separate symptom validity tests with that of the F and FP scales and the Fake Bad Scale (FBS). The RBS consistently outperformed F, FP, and FBS. Study results suggest that the RBS may be a useful addition to existing MMPI-2 validity scales and indices in detecting symptom complaints predominantly associated with cognitive response bias and overreporting in forensic neuropsychological and disability assessment settings.
Axis I Screens and Suicide Risk in Jails
Authors: Harrison Kimberly S. , Rogers Richard
Published: May 2007

Mental health professionals conducting screenings in jail settings face formidable challenges in identifying inmates at risk for major depression and suicide. Psychologists often rely on correctional staff to provide initial appraisals of those inmates requiring further evaluation. In a sample of 100 jail detainees, the effectiveness of two specialized screens (the Referral Decision Scale and Mental Disability/Suicide Intake Screen or MDSIS) and one general screen (Personality Assessment Screener or PAS) was evaluated. For suicidal ideation, the MDSIS composite score evidenced promise (sensitivity = 1.00; specificity = 0.71). In ruling out major depression, the PAS Negative Affect subscale was useful for the inmate participants.
Convergent Validity of the Youth Psychopathic Traits Inventory (YPI)
Authors: Andershed Henrik , Hodgins Sheilagh , Tengström Anders
Published: May 2007

This study investigates the relationship between the self-report Youth Psychopathic Traits Inventory (YPI) and the clinician-rated Psychopathy Checklist: Youth Version (PCL:YV). A representative sample of 92 girls and 70 boys, 12 to 20 years of age (mean age, 17 years), who received services at a clinic for adolescents with substance misuse problems, was studied. Moderate correlations (r = .30—.51) were found between conceptually corresponding YPI and PCL:YV factor scores among both boys and girls, whereas correlations between individual subscales of the YPI and items of the PCL:YV were not as consistent. A cross-tabulation of groupings based on the three-factor models of the two instruments largely supported the categorical convergent validity of the YPI, particularly for low and high scorers. Although more studies with larger samples are needed, results indicate that the YPI is a cost-effective measure of psychopathic traits in adolescents in research settings.
Machining Dynamics Involving Whirling Part II: Machining Motions Described by Nonlinear and Linearized Models
Authors: Dassanayake Achala V. , Suh C. Steve
Published: May 2007

The nonlinear model presented in Part I is linearized and numerically evaluated to investigate the impact of linearization on interpreting turning dynamics. As described in Part I, the equations of motion are so derived that the motion of the workpiece machining surface is in the plane orthogonal to the spindle axis and the motion of the tool is along the axis and coupled with the machining surface. The nonlinear 3D model is linearized about an operating point at (0, 0, Z0), where zt = Z0 is the equilibrium location of the tool associated with the ( x2 = 0 , y2 = 0) position of the workpiece. The (0, 0, Z0 ) operating point is selected to satisfy the ultimate machining goal for always achieving precise workpiece geometry without surface error and waviness. Taylor series expansion about the operating point is applied to linearize the nonlinear equations of motion. Modifications are also made to the nonlinear tool stiffness term and the cutting force to minimize linearization errors. The mass and stiffness of the workpiece remain functions of time after the modifications are performed. Numerical results show that the linearized model underestimates tool vibrations in the time domain and overestimates system behavior in the frequency domain; whereas the nonlinear model agrees with the physical results reported in the literature in describing machining stability and chatter.
Dynamic Stability Analysis of a Cracked Nonlinear Rotor System Subjected to Periodic Excitations in Machining
Authors: Dai Liming , Chen Changping
Published: May 2007

This research intends to analyze the dynamic stability of a nonlinear cracked rotor system with unsymmetrical viscoelastic supports. Nonlinear governing equations for the cracked rotor system subjected to periodic forces generated in machining are established. The linear and nonlinear dynamic stabilities of the system are investigated on the basis of the HBM method, utilizing Lyapunov theory and the Floquet criterion. The effects of the masses of shaft and disk together with the nonlinearity of the rotating system on the behavior of the system are all taken into consideration. Numerical simulations of the system are also performed. The influences of various factors on the principal regions of instability are studied. The results obtained in the research are compared with those found in the literature.
Nonlinear Vibration of Heated Co-rotating Disks
Authors: Saniei Nader , Luo Albert C.J.
Published: May 2007

Nonlinear vibrations of co-rotating disks with thermal effects are investigated under non-uniform temperature distributions relative to airflow induced by disk rotation. For analytical investigation of thermal effects, the temperature distribution patterns are obtained through the heat transfer coefficients measurements. The natural frequencies for symmetric and asymmetric responses of an 86 mm diameter computer memory disk are computed. When the disk is heated, its stiffness becomes larger for the two lowest nodal diameter numbers and smaller for the other nodal diameter numbers. This implies that the vibration of heated, rotating disks for the higher nodal diameter numbers may be induced more easily than the cooled one.
On Constitutive Models for Limited Elastic, Molecular Based Materials
Authors: Beatty Millard F.
Published: May 2007

The response function for a general class of elastic molecular based materials characterized by their limiting molecular chain extensibility and depending on only the first principal invariant of the Cauchy— Green deformation tensor together with a certain molecular based limiting extensibility parameter is introduced. The constitutive response function for the Gent material is then derived inversely as the [0/1] Padé approximant of this class, a result that leads naturally to an infinite geometric series representation of its response function. Truncation of this series function characterizes a familiar class of quadratic materials now having physically relevant material constants. It is shown that the [0/2] approximant of the response function for the general class of restricted elastic materials leads inversely to a new constitutive model and its series representation. Of course, many familiar limited elastic material models are members of the general class. The Padé approximants for some response functions are not, and empirical modifications that admit these as members of the general class are described. Examples of two limited elastic models in the class that are not Padé approximants are noted. The strain energy functions for a few of the restricted elastic models described are presented.
Determination of the Mechanical Properties of a Solid Elastic Medium from a Seismic Wave Propagation Using Two Statistical Estimators
Authors: Zein Samih , Canot Édouard , Erhel Jocelyne , Nassif Nabil
Published: May 2007

In this paper, we study an inverse problem consisting in the determination of the mechanical properties of a layered solid elastic medium in contact with a fluid medium by measuring the variation of the pressure in the fluid while propagating a seismic/acoustic wave. The estimation of mechanical parameters of the solid is obtained from the simulation of a seismic wave propagation model governed by a system of partial differential equations.

Two stochastic methods, Markov chain Monte Carlo with an accelerated version and simultaneous perturbation stochastic approximation, are implemented and compared with respect to cost and accuracy.
Explicit Bounds of Effective Stiffness Tensors for Textured Aggregates of Cubic Crystallites
Authors: Mojia Huang  , Man Chi-Sing
Published: May 2007

For isotropic aggregates of cubic crystallites, Hashin and Shtrikman derived lower and upper bounds for the effective stiffness tensor, which are tighter than the lower and upper bound provided by the Reuss and Voigt model, respectively. In this paper we consider anisotropic aggregates of cubic crystallites with arbitrary texture. We model the elastic polycrystal in question as an assemblage of space-filling spherical grains. Moreover, we assume that every point within one grain has the same crystallographic orientation, whereas the orientations of different grains are uncorrelated. Under this model, we appeal to the variational principles of Hashin and Shtrikman and derive explicit lower and upper bounds for the effective stiffness tensor, which are quadratic in texture coefficients and carry parameters given in terms of the single-crystal elastic constants. For weakly-textured aggregates of cubic crystallites, several examples suggest that our bounds for the effective elastic tensor provide estimates much tighter than those delivered by the Reuss lower bound and the Voigt upper bound.
Children's usage of media technologies and psychosocial factors
Authors: Heim Jan , Brandtzæg Petter Bae , Kaare Birgit Hertzberg , Endestad Tor , Torgersen Leila
Published: May 2007

Media use has changed considerably during the past five years and earlier research has produced contradictory results on how media use links to children's psychosocial factors. This study charts the access to and use of several media technologies among 825 Norwegian schoolchildren between 10 and 12 years of age. The questionnaire contained items concerning children's self-concept, parental monitoring and social competence. It found that children engage with different kind of media activities and some of these are significantly related to psychosocial factors, however, these correlations were in general quite small. Entertainment usage was associated with low scholastic competence. Both utility usage and heavy advanced usage of new media were related to self-perceptions of athletic competence. Low social acceptance was linked to Gameboy usage and advanced usage of media. Finally, there was a relationship between experienced parental monitoring and utility usage of media technology. The possible implications for these empirical relations are discussed.
Globalization, promotional culture and the production/consumption of online games: engaging Adidas's `Beat Rugby' Campaign
Authors: Scherer Jay
Published: May 2007

Issues pertaining to the production and consumption of corporate websites and online games remain relatively unexplored. This study examines the cultural production of a free, downloadable rugby game and parallel website for Adidas's sponsorship of the New Zealand All Blacks entitled `Beat Rugby'. Produced by Saatchi & Saatchi Wellington to articulate the Adidas brand as globally cool, the promotional apparatus targeted a specific niche of Adidas's company-wide target market known as the `jeeks': male, sports-loving and computer literate 12—20-year-olds. More than 43,000 participants downloaded and played in the three-month tournament with the winners, the virtual 15 All Blacks, flown to New Zealand to meet their `real' counterparts. The game and electronic community facilitated a range of consumption and communication experiences for a transnational audience of post-fans in a branded environment which was monitored by the cultural intermediaries at Saatchi & Saatchi on behalf of their client.
Nation-building and the diaspora on Leonenet: a case of Sierra Leone in cyberspace
Authors: Tynes Robert
Published: May 2007

The nation-state of Sierra Leone crumbled during the 1990s. A decade-long civil war destroyed the state and brutalized the national imaginings. Despite the lack of institutional structure, some members of its society chose to keep the nation alive through discourse on a listserv, an email forum called Leonenet. Using a multi-methodological approach that incorporated content analysis, interviews with cultural informants, ethnography and participant observation, the findings of the study reported in this article indicate that list members had created a virtual nation, defined as any community that communicates in cyberspace, whose collective discourse and/or actions are aimed towards the building, binding, maintenance, rebuilding or rebinding of a nation. Leonenet was a diasporic communicative space where Sierra Leone's state-related symbols were generated and then held in conceptual escrow, waiting for the institutional structure to return.
Building a Tatar elite
Authors: Alvarez Veinguer Aurora , Davis Howard H.
Published: May 2007

Tatarstan, a bi-cultural region in the Russian Federation, has been experiencing a significant revival of Tatar language, culture and ethnic identities during the post-Soviet period. This article examines the significance of language policy in schools, and elite Tatar schools in particular, for this Tatar renaissance. It describes the political context and institutional setting and uses qualitative research data to analyse ethnic identification among pupils, parents and teachers. It shows that language has central importance in the Tatar schools and is treated as essential to what it means to be Tatar. Till now, the `Tatarstan model' of partial autonomy within the Russian Federation has successfully accommodated ethnic diversity. However, asymmetries between `national' education in Tatar schools and predominantly Russian education in non-Tatar schools have potential to generate tensions, as the republic of Tatarstan develops its policies for interethnic relations, religion and culture.
Human CD4+CD25+ regulatory T cells: proteome analysis identifies galectin-10 as a novel marker essential for their anergy and suppressive function
Authors: Kubach Jan , Lutter Petra , Bopp Tobias , Stoll Sabine , Becker Christian , Huter Eva , Richter Christoph , Weingarten Petra , Warger Tobias , Knop Jürgen , Müllner Stefan , Wijdenes John , Schild Hansjörg , Schmitt Edgar , Jonuleit Helmut
Published: May 2007

CD4+CD25+Foxp3+ regulatory T cells (CD25+ Treg cells) direct the maintenance of immunological self-tolerance by active suppression of autoaggressive T-cell populations. However, the molecules mediating the anergic state and regulatory function of CD25+ Treg cells are still elusive. Using differential proteomics, we identified galectin-10, a member of the lectin family, as constitutively expressed in human CD25+ Treg cells, while they are nearly absent in resting and activated CD4+ T cells. These data were confirmed on the mRNA and protein levels. Single-cell staining and flow cytometry showed a strictly intracellular expression of galectin-10 in CD25+ Treg cells. Specific inhibition of galectin-10 restored the proliferative capacity of CD25+ Treg cells and abrogated their suppressive function. Notably, first identified here as expressed in human T lymphocytes, galectin-10 is essential for the functional properties of CD25+ Treg cells.
Small-molecule agonists of SHIP1 inhibit the phosphoinositide 3-kinase pathway in hematopoietic cells
Authors: Ong Christopher J. , Ming-Lum Andrew , Nodwell Matt , Ghanipour Ali , Yang Lu , Williams David E. , Kim Joseph , Demirjian Loutfig , Qasimi Pooran , Ruschmann Jens , Cao Li-Ping , Ma Kewei , Chung Stephen W. , Duronio Vincent , Andersen Raymond J. , Krystal Gerald , Mui Alice L.-F.
Published: May 2007

Because phosphoinositide 3-kinase (PI3K) plays a central role in cellular activation, proliferation, and survival, pharmacologic inhibitors targeting components of the PI3K pathway are actively being developed as therapeutics for the treatment of inflammatory disorders and cancer. These targeted drugs inhibit the activity of either PI3K itself or downstream protein kinases. However, a previously unexplored, alternate strategy is to activate the negative regulatory phosphatases in this pathway. The SH2-containing inositol-5′-phosphatase SHIP1 is a normal physiologic counter-regulator of PI3K in immune/hematopoietic cells that hydrolyzes the PI3K product phosphatidylinositiol-3,4,5-trisphosphate (PIP3). We now describe the identification and characterization of potent and specific small-molecule activators of SHIP1. These compounds represent the first small-molecule activators of a phosphatase, and are able to activate recombinant SHIP1 enzyme in vitro and stimulate SHIP1 activity in intact macrophage and mast cells. Mechanism of activation studies with these compounds suggest that they bind a previously undescribed, allosteric activation domain within SHIP1. Furthermore, in vivo administration of these compounds was protective in mouse models of endotoxemia and acute cutaneous anaphylaxis, suggesting that SHIP1 agonists could be used therapeutically to inhibit the PI3K pathway.
Generation of novel high quality HMW-GS genes in two introgression lines of Triticum aestivum/Agropyron elongatum
Authors: Liu Shuwei , Zhao Shuangyi , Chen Fanguo , Xia Guangmin
Published: May 2007

Background

High molecular weight glutenin subunits (HMW-GS) have been proved to be mostly correlated with the processing quality of common wheat (Triticum aestivum). But wheat cultivars have limited number of high quality HMW-GS. However, novel HMW-GS were found to be present in many wheat asymmetric somatic hybrid introgression lines of common wheat/Agropyron elongatum.

Results

To exploit how these new subunits were generated, we isolated HMW-GS genes from two sib hybrid lines (II-12 and 11-4-6) and compared them with those from their parents. The result shows that two genes of hybrid (H11-3-3 and H11-4-3) are directly introgressed from the donor parent Agropyron elongatum; one hybrid gene (H1Dx5) comes from point mutation of a parental wheat gene (1Dx2.1); two other hybrid genes (H1By8 and H1By16) are likely resulting from unequal crossover or slippage of a parental wheat gene (1By9.1); and the sixth novel hybrid gene (H1Dy12) may come from recombination between two parental genes.

Conclusion

Therefore, we demonstrate that novel HMW-GS genes can be rapidly created through asymmetric somatic hybridization in a manner similar with the evolution mechanism of these genes supposed before. We also described gene shuffling as a new mechanism of novel HMW-GS gene formation in hybrids. The results suggest that asymmetric somatic hybridization is an important approach for widening HMW-GS genebank of wheat quality improvement.
Transcriptional analysis of an immune-responsive serine protease from Indian malarial vector, Anopheles culicifacies
Authors: Rodrigues Janneth , Agrawal Neema , Sharma Anil , Malhotra Pawan , Adak Tridibes , Chauhan Virander S , Bhatnagar Raj K
Published: May 2007

Background

The main vector for transmission of malaria in India is the Anopheles culicifacies mosquito species, a naturally selected subgroup of which is completely refractory (R) to transmission of the malaria parasite, Plasmodium vivax;

Results

Here, we report the molecular characterization of a serine protease (acsp30)-encoding gene from A. culicifacies, which was expressed in high abundance in the refractory strain compared to the susceptible (S) strain. The transcriptional upregulation of acsp30 upon Plasmodium challenge in the refractory strain coincided with ookinete invasion of mosquito midgut. Gene organization and primary sequence of acsp30 were identical in the R and S strains suggesting a divergent regulatory status of acsp30 in these strains. To examine this further, the upstream regulatory sequences of acsp30 were isolated, cloned and evaluated for the presence of promoter activity. The 702 bp upstream region of acsp30 from the two strains revealed sequence divergence. The promoter activity measured by luciferase-based reporter assay was shown to be 1.5-fold higher in the R strain than in the S. Gel shift experiments demonstrated a differential recruitment of nuclear proteins to upstream sequences of acsp30 as well as a difference in the composition of nuclear proteins in the two strains, both of which might contribute to the relative abundance of acsp30 in the R strain;

Conclusion

The specific upregulation of acsp30 in the R strain only in response to Plasmodium infection is suggestive of its role in contributing the refractory phenotype to the A. culicifacies mosquito population.
Paediatric out-of-hospital resuscitation in an area with scattered population (Galicia-Spain)
Authors: Fernández Pilar Blanco-Ons , Sánchez-Santos Luis , Rodríguez-Núñez Antonio , Iglesias-Vázquez José Antonio , Cegarra-García María , Barreiro-Díaz Maria Victoria
Published: May 2007

Background

Cardiorespiratory arrest (CRA) is a rare event in childhood. Our objective was to determine the characteristics of paediatric CRA and the immediate results of cardiopulmonary resuscitation (CPR) in Galicia, a community with a very scattered population.

Methods

All children (aged from newborn to 16 years old) who suffered an out-of-hospital CRA in Galicia and were assisted by the Public Foundation Medical Emergencies of Galicia-061 staff, from June 2002 to February 2005, were included in the study. Data were prospectively recorded following the Utstein's style guidelines.

Results

Thirty-one cases were analyzed (3.4 CRA annual cases per 100.000 paediatric population). The arrest was respiratory in 16.1% and cardiac in 83.9% of cases. CRA occurred at home in 58.1% of instances. Time CRA to initiation of CPR was shorter than 10 minutes in 32.2% and longer than 20 minutes in 29.0% of cases. 22.6% of children received bystander CPR. The first recorded rhythm was asystole in 67.7% of cases. Bag-mask ventilation was used in 67.7% and in 83.8% oro-tracheal intubation was done. A peripheral venous access was achieved in 67.7% and intraosseous access was used in 16.1% of patients. 93.5% of children were treated with adrenaline. After initial CPR, sustained restoration of spontaneous circulation was achieved in 38.7% of cases. Six children (19.4%) survived until hospital discharge. Four of 5 children with respiratory arrest survived, whereas only 2 of 26 children with cardiac arrest survived until hospital discharge.

Conclusion

Despite the handicap of a highly disseminated population, paediatric CRA characteristics and CPR results in Galicia are comparable to references from other communities. Programs to increase bystander CPR, equip laypeople with basic CPR skills and to update life support knowledge of health staff are needed to improve outcomes.