bluuebunny/crossref_metadata_2025 huggingface dataset:
Sonic Hedgehog Regulates Integrin Activity, Cadherin Contacts, and Cell Polarity to Orchestrate Neural Tube Morphogenesis
Authors: Fournier-Thibault Claire , Blavet Cédrine , Jarov Artem , Bajanca Fernanda , Thorsteinsdóttir Sólveig , Duband Jean-Loup
Published: October 2009

In vertebrates, the embryonic nervous system is shaped and patterned by a series of temporally and spatially regulated cell divisions, cell specifications, and cell adhesions and movements. Morphogens of the Hedgehog, Wnt, and bone morphogenetic protein families have been shown to play a crucial role in the control of cell division and specification in the trunk neural tube, but their possible implication in the regulation of adhesive events has been poorly documented. In the present study, we demonstrate that Sonic hedgehog regulates neural epithelial cell adhesion and polarity through regulation of integrin activity, cadherin cell–cell contact, and cell polarity genes in immature neural epithelial cells before the specification of neuronal cells. We propose that Sonic hedgehog orchestrates neural tube morphogenesis by coordinating adhesive and motility events with cell proliferation and differentiation.
Synchronous with Your Feelings: Sensorimotor γ Band and Empathy for Pain
Authors: Betti Viviana , Zappasodi Filippo , Rossini Paolo Maria , Aglioti Salvatore Maria , Tecchio Franca
Published: October 2009

Neuroscience studies on the social sharing of observed or imagined pain focused on whether empathic pain resonance is linked to affective or sensory nodes of the pain matrix. However, empathy, like other complex cognitive processes, is inherently linked to the activation of functional networks rather than of separate brain areas. Here, we used magnetoencephalography (MEG) to explore the relationship between empathy and functional coupling of neuronal activity in primary somatosensory (SI) and motor (MI) cortices. MEG recording was performed while healthy participants observed movie-clips depicting the static hand of a stranger model, the same hand deeply penetrated by a needle, or gently touched by a Q-tip. Subjects were asked to rate the movie-derived sensations attributed to self or to the model. For each type of clip observation, we analyzed spectral power and coherence values in α, β, and γ frequency bands. While spectral power indexes separate neural activity in SI and MI, coherence values index functional cross-talk between these two areas. No power changes of SI or MI sources were induced by observation conditions in any of the frequency bands. Crucially, γ-band coherence values were significantly higher during needle-in-hand than touch and static hand observation and correlated with self-and other-referred pain ratings derived from needle-in-hand movies observation. Thus, observation of others' pain increases neuronal synchronization and cross-talk between the onlookers' sensory and motor cortices, indicating that empathic resonance relies upon the activity of functional networks more than of single areas.
Impedance Control Reduces Instability That Arises from Motor Noise
Authors: Selen Luc P. J. , Franklin David W. , Wolpert Daniel M.
Published: October 2009

There is ample evidence that humans are able to control the endpoint impedance of their arms in response to active destabilizing force fields. However, such fields are uncommon in daily life. Here, we examine whether the CNS selectively controls the endpoint impedance of the arm in the absence of active force fields but in the presence of instability arising from task geometry and signal-dependent noise (SDN) in the neuromuscular system. Subjects were required to generate forces, in two orthogonal directions, onto four differently curved rigid objects simulated by a robotic manipulandum. The endpoint stiffness of the limb was estimated for each object curvature. With increasing curvature, the endpoint stiffness increased mainly parallel to the object surface and to a lesser extent in the orthogonal direction. Therefore, the orientation of the stiffness ellipses did not orient to the direction of instability. Simulations showed that the observed stiffness geometries and their pattern of change with instability are the result of a tradeoff between maximizing the mechanical stability and minimizing the destabilizing effects of SDN. Therefore, it would have been suboptimal to align the stiffness ellipse in the direction of instability. The time course of the changes in stiffness geometry suggests that modulation takes place both within and across trials. Our results show that an increase in stiffness relative to the increase in noise can be sufficient to reduce kinematic variability, thereby allowing stiffness control to improve stability in natural tasks.
An Integrated Systems Analysis Implicates EGR1 Downregulation in Simian Immunodeficiency Virus Encephalitis-Induced Neural Dysfunction
Authors: Gersten Merril , Alirezaei Mehrdad , Marcondes Maria Cecilia Garibaldi , Flynn Claudia , Ravasi Timothy , Ideker Trey , Fox Howard S.
Published: October 2009

Human immunodeficiency virus (HIV)-associated dementia (HAD) is a syndrome occurring in HIV-infected patients with advanced disease that likely develops as a result of macrophage and microglial activation as well as other immune events triggered by virus in the central nervous system. The most relevant experimental model of HAD, rhesus macaques exhibiting simian immunodeficiency virus (SIV) encephalitis (SIVE), closely reproduces the human disease and has been successfully used to advance our understanding of mechanisms underlying HAD. In this study we integrate gene expression data from uninfected and SIV-infected hippocampus with a human protein interaction network and discover modules of genes whose expression patterns distinguish these two states, to facilitate identification of neuronal genes that may contribute to SIVE/HIV cognitive deficits. Using this approach we identify several downregulated candidate genes and select one, EGR1, a key molecule in hippocampus-related learning and memory, for further study. We show that EGR1 is downregulated in SIV-infected hippocampus and that it can be downregulated in differentiated human neuroblastoma cells by treatment with CCL8, a product of activated microglia. Integration of expression data with protein interaction data to discover discriminatory modules of interacting proteins can be usefully used to prioritize differentially expressed genes for further study. Investigation of EGR1, selected in this manner, indicates that its downregulation in SIVE may occur as a consequence of the host response to infection, leading to deficits in cognition.
Synaptic Circuit Abnormalities of Motor-Frontal Layer 2/3 Pyramidal Neurons in an RNA Interference Model of Methyl-CpG-Binding Protein 2 Deficiency
Authors: Wood Lydia , Gray Noah W. , Zhou Zhaolan , Greenberg Michael E. , Shepherd Gordon M. G.
Published: October 2009

Rett syndrome, an autism spectrum disorder with prominent motor and cognitive features, results from mutations in the gene for methyl-CpG-binding protein 2 (MeCP2). Here, to identify cortical circuit abnormalities that are specifically associated with MeCP2 deficiency, we used glutamate uncaging and laser scanning photostimulation to survey intracortical networks in mouse brain slices containing motor-frontal cortex. We usedin uterotransfection of short hairpin RNA constructs to knock down MeCP2 expression in a sparsely distributed subset of layer (L) 2/3 pyramidal neurons in wild-type mice, and compared input maps recorded from transfected-untransfected pairs of neighboring neurons. The effect of MeCP2 deficiency on local excitatory input pathways was severe, with an average reduction in excitatory synaptic input from middle cortical layers (L3/5A) of >30% compared with MeCP2-replete controls. MeCP2 deficiency primarily affected the strength, rather than the topography, of excitatory intracortical pathways. Inhibitory synaptic inputs and intrinsic eletrophysiological properties were unaffected in the MeCP2-knockdown neurons. These studies indicate that MeCP2 deficiency in individual postsynaptic cortical pyramidal neurons is sufficient to induce a pathological synaptic defect in excitatory intracortical circuits.
Intracranial EEG Reveals a Time- and Frequency-Specific Role for the Right Inferior Frontal Gyrus and Primary Motor Cortex in Stopping Initiated Responses
Authors: Swann Nicole , Tandon Nitin , Canolty Ryan , Ellmore Timothy M. , McEvoy Linda K. , Dreyer Stephen , DiSano Michael , Aron Adam R.
Published: October 2009

Inappropriate response tendencies may be stopped via a specific fronto/basal ganglia/primary motor cortical network. We sought to characterize the functional role of two regions in this putative stopping network, the right inferior frontal gyrus (IFG) and the primary motor cortex (M1), using electocorticography from subdural electrodes in four patients while they performed a stop-signal task. On each trial, a motor response was initiated, and on a minority of trials a stop signal instructed the patient to try to stop the response. For each patient, there was a greater right IFG response in the beta frequency band (∼16 Hz) for successful versus unsuccessful stop trials. This finding adds to evidence for a functional network for stopping because changes in beta frequency activity have also been observed in the basal ganglia in association with behavioral stopping. In addition, the right IFG response occurred 100–250 ms after the stop signal, a time range consistent with a putative inhibitory control process rather than with stop-signal processing or feedback regarding success. A downstream target of inhibitory control is M1. In each patient, there was alpha/beta band desynchronization in M1 for stop trials. However, the degree of desynchronization in M1 was less for successfully than unsuccessfully stopped trials. This reduced desynchronization on successful stop trials could relate to increased GABA inhibition in M1. Together with other findings, the results suggest that behavioral stopping is implemented via synchronized activity in the beta frequency band in a right IFG/basal ganglia network, with downstream effects on M1.
Plasminogen Enhances Neuritogenesis on Laminin-1
Authors: Gutiérrez-Fernández Ana , Gingles Neill A. , Bai Hongdong , Castellino Francis J. , Parmer Robert J. , Miles Lindsey A.
Published: October 2009

Proteins of the plasminogen activation system are broadly expressed throughout the nervous system, and key roles for these proteins in neuronal function have been demonstrated. Recent reports have established that plasminogen is synthesized in neuroendocrine tissues, making this protein and the proteolytic activity of the product of its activation, plasmin, available at sites separated anatomically from circulating, hepatocyte-derived plasminogen. Results with plasminogen-deficient humans and mice suggest a role for plasminogen in neuritogenesis. To elucidate the role of the plasminogen activation system in these processes, the function of plasminogen during neuritogenesis and neurite outgrowth was studied. It is shown here that plasminogen participates in neuritogenesis, as plasmin inhibitors reduced both neurite outgrowth and neurite length in PC-12 cells. The addition of exogenous plasminogen enhanced neurite outgrowth and neurite length in both PC-12 cells and primary cortical neurons. The proteolytic activity of plasmin was required, since mutation of the catalytic serine residue completely abolished the stimulatory activity. Furthermore, mutation of the lysine binding site within kringle 5 of the plasminogen molecule also reduced the neuritogenic activity of plasminogen. Additionally, we demonstrate that plasminogen specifically bound to laminin-1, the interaction resulted in increased plasminogen activation by tissue-type plasminogen activator, and was dependent on a functional lysine binding site within plasminogen kringle 5. Moreover, during NGF-induced neuritogenesis, laminin-1 was degraded, and this cleavage was catalyzed by plasmin. This study provides the first direct evidence that plasminogen participates in neurite outgrowth and also suggests that laminin-1 degradation by plasmin contributes to the process of neuritogenesis.
Essential Role of Cytoplasmic cdk5 and Prx2 in Multiple Ischemic Injury Models,In Vivo
Authors: Rashidian Juliet , Rousseaux Maxime W. , Venderova Katerina , Qu Dianbo , Callaghan Steve M. , Phillips Maryam , Bland Ross J. , During Matthew J. , Mao Zixu , Slack Ruth S. , Park David S.
Published: October 2009

Recent evidence suggests that abnormal activation of cyclin-dependent kinase 5 (cdk5) is a critical prodeath signal in stroke. However, the mechanism(s) by which cdk5 promotes death is unclear. Complicating the role of cdk5 are the observations that cdk5 can exist in multiple cellular regions and possess both prosurvival and prodeath characteristics. In particular, the critical role of cytoplasmic or nuclear cdk5 in neuronal jury,in vivo, is unclear. Therefore, we determined where cdk5 was activated in models of ischemia and how manipulation of cdk5 in differing compartments may affect neuronal death. Here, we show a critical function for cytoplasmic cdk5 in both focal and global models of stroke,in vivo. Cdk5 is activated in the cytoplasm and expression of DNcdk5 localized to the cytoplasm is protective. Importantly, we also demonstrate the antioxidant enzyme Prx2 (peroxiredoxin 2) as a critical cytoplasmic target of cdk5. In contrast, the role of cdk5 in the nucleus is context-dependent. Following focal ischemia, nuclear cdk5 is activated and functionally relevant while there is no evidence for such activation following global ischemia. Importantly, myocyte enhancer factor 2D (MEF2D), a previously described nuclear target of cdk5in vitro, is also phosphorylated by cdk5 following focal ischemia. In addition, MEF2D expression in this paradigm ameliorates death. Together, our results address the critical issue of cdk5 activity compartmentalization, as well as define critical substrates for both cytoplasmic and nuclear cdk5 activity in adult models of stroke.
The PPAR-γ Pro12Ala polymorphism associates with weight gain during GH-treatment in short children born small for gestational age
Authors: de Kort Sandra W K , Hokken-Koelega Anita C S
Published: October 2009

Context

Short children born small for gestational age (SGA) have a lean phenotype with lower insulin sensitivity and higher blood pressure. GH treatment results in weight gain, and a decrease in blood pressure and insulin sensitivity. However, not all children respond in the same way. The Pro12Ala polymorphism of the peroxisome proliferator-activated receptor (PPAR-γ) gene is inversely associated with body mass index (BMI), changes in BMI and the risk to develop type 2 diabetes mellitus.

Objective

To analyze the contribution of thePPAR-γPro12Ala polymorphism to GH induced changes in determinants of metabolic and cardiovascular disease in short SGA children.

Methods

PPAR-γwas genotyped in 238 Caucasian short SGA children (mean age 7.5 years). Height, weight, blood pressure, and serum lipids were measured before start and during 4 years of GH treatment. In addition, glucose homeostasis by homeostasis model assessment insulin resistance ratio (HOMA-IR) (n=148) and by frequently sampled i.v. glucose tolerance test (n=51), and body composition by dual energy X-ray absorptiometry (n=79) were measured.

Results

At baseline, the Ala12 allele was not associated with any determinant of metabolic and cardiovascular disease. After 4 years of GH treatment, the increase in weight for height SDS and BMI SDS was significantly greater in carriers of an Ala12 allele than in noncarriers. The change in all other parameters was not associated with Pro12Ala genotype.

Conclusion

The Ala12 variant of thePPAR-γgene is associated with higher weight gain during GH treatment but not with changes in determinants of metabolic and cardiovascular diseases in Caucasian subjects born SGA.
Should Patients with High-Risk Soft Tissue Sarcoma Receive Adjuvant Chemotherapy?
Authors: Schuetze Scott M. , Patel Shreyaskumar
Published: October 2009

Learning Objectives

After completing this course, the reader will be able to: Describe the type of patient with soft tissue sarcoma most likely to benefit from adjuvant chemotherapy.Select the chemotherapy regimen most likely to benefit a patient with high-risk soft tissue sarcoma.Evaluate the impact of adjuvant chemotherapy on risk of soft tissue sarcoma recurrence analyzed in the sarcoma meta-analyses.

This article is available for continuing medical education credit at CME.TheOncologist.com

Soft tissue sarcoma is a malignant connective tissue tumor that may arise anywhere in the body and from diverse mesenchymal elements. Its incidence is approximately 30 per million persons. The majority of patients with soft tissue sarcoma present with potentially life-threatening disease, and complete resection to obtain specimen margins free of tumor and radiation offer the best chance for local disease control. The risk of relapse and death from disease rises with increasing tumor stage, grade, and size. Adjuvant chemotherapy has been studied as a means to decrease the risk for disease recurrence in patients with localized soft tissue sarcoma at diagnosis, but the majority of trials reported on have been hampered by patient heterogeneity, low patient accrual, and short follow-up. Meta-analysis and reviews of institutional large series, in efforts to overcome some of the limitations, suggest that doxorubicin with ifosfamide reduces the risk for sarcoma recurrence and death in selected patients with high-grade, large, and chemotherapy-sensitive sarcoma subtypes to a clinically meaningful degree. In multiple analyses, patients with high-risk soft tissue sarcoma treated with chemotherapy have a >10% absolute lower risk for disease recurrence and longer disease-specific survival than patients treated without chemotherapy. In the absence of conclusive results from an adequately powered, randomized, controlled clinical trial, the available data support the use of chemotherapy in the management of high-risk, localized, soft tissue sarcoma.
The Assessment and Management of Delirium in Cancer Patients
Authors: Bush Shirley H. , Bruera Eduardo
Published: October 2009

Learning Objectives

After completing this course, the reader will be able to: Summarize the current evidence regarding strategies for the assessment and management of delirium in advanced cancer.Outline the medications most commonly implicated for drug-induced delirium.Compare the various pharmacological agents available for use in managing cancer-related delirium.

This article is available for continuing medical education credit at CME.TheOncologist.com

Delirium remains the most common and distressing neuropsychiatric complication in patients with advanced cancer. Delirium causes significant distress to patients and their families, and continues to be underdiagnosed and undertreated. The most frequent, consistent, and, at the same time, reversible etiology is drug-induced delirium resulting from opioids and other psychoactive medications. The objective of this narrative review is to outline the causes of delirium in advanced cancer, especially drug-induced delirium, and the diagnosis and management of opioid-induced neurotoxicity. The early symptoms and signs of delirium and the use of delirium-specific assessment tools for routine delirium screening and monitoring in clinical practice are summarized. Finally, management options are reviewed, including pharmacological symptomatic management and also the provision of counseling support to both patients and their families to minimize distress.
Adjuvant Chemotherapy in Localized Soft Tissue Sarcomas: Still Not Proven
Authors: Blay Jean-Yves , Le Cesne Axel
Published: October 2009

Soft tissue sarcoma is a rare and heterogeneous group of tumors in terms of histological subtypes, molecular alterations, clinical presentation, and prognosis. Yet, these tumors are most often treated similarly in the localized phase. The standard treatment of these patients requires multidisciplinary management, in particular, careful diagnostic procedures and surgery by an expert physician, preceded or followed by external radiotherapy. The utility of adjuvant chemotherapy has been explored in 14 trials comparing adjuvant chemotherapy with no treatment. Several trials reported a lower risk for local relapse and lower risk for metastatic relapse, but only a few small trials reported longer overall survival. A meta-analysis of all trials failed to demonstrate a significant difference in the relapse-free survival (RFS) or overall survival rates. Two additional trials, reported afterward, presented conflicting results, with a significant benefit in terms of the RFS rate for the trial of the Italian Sarcoma Group, but no difference in the RFS or overall survival rate in the most recent European Organization for Research and Treatment of Cancer trial. We conclude that adjuvant chemotherapy has not been proven to improve the outcome of an unselected population of patients. Several hypotheses are proposed to account for this observation.
Expression of hypoxia-inducible factor 1α in thyroid carcinomas
Authors: Burrows N , Resch J , Cowen R L , von Wasielewski R , Hoang-Vu C , West C M , Williams K J , Brabant G
Published: October 2009

Hypoxia-inducible factor 1α (HIF-1α) is upregulated by hypoxia and oncogenic signalling in many solid tumours. Its regulation and function in thyroid carcinomas are unknown. We evaluated the regulation of HIF-1α and target gene expression in primary thyroid carcinomas and thyroid carcinoma cell lines (BcPAP, WRO, FTC-133 and 8505c). HIF-1α was not detectable in normal tissue but was expressed in thyroid carcinomas. Dedifferentiated anaplastic tumours (ATCs) exhibited high levels of nuclear HIF-1α staining. The HIF-1 target glucose transporter 1 was expressed to a similar level in all tumour types, whereas carbonic anhydrase-9 was significantly elevated in ATCs. In vitro studies revealed a functionally active HIF-1α pathway in thyroid cells with transcriptional activation observed after graded hypoxia (1% O2, anoxia) or treatment with a hypoxia mimetic cobalt chloride. High basal and hypoxia-induced expression of HIF-1α in FTC-133 cells that harbour a phosphatase and tensin homologue (PTEN) mutation was reduced by introduction of wild-type PTEN. Similarly, pharmacological inhibition of the phosphoinositide 3-kinase (PI3K) pathway using LY294002 inhibited HIF-1α and HIF-1α targets in all cell lines, including those with B-RAF mutations (BcPAP and 8505c). In contrast, the effects of inhibition of the RAF/MEK/extracellular signal-regulated kinase pathway were restricted by environmental condition and B-RAF mutation status. HIF-1 is functionally expressed in thyroid carcinomas and is regulated not only by hypoxia but also via growth factor signalling pathways and, in particular, the PI3K pathway. Given the strong association of HIF-1α with an aggressive disease phenotype and therapeutic resistance, this pathway may be an attractive target for improved therapy in thyroid carcinomas.
Stress sensitivity is increased in transgenic rats with low brain angiotensinogen
Authors: Müller Helge , Kröger Juliane , Jöhren Olaf , Szymczak Silke , Bader Michael , Dominiak Peter , Raasch Walter
Published: October 2009

AT1 blockers attenuate hypothalamo-pituitary–adrenal (HPA) axis reactivity in hypertension independently of their potency to lower blood pressure. A reduced pituitary sensitivity to CRH and a downregulation of hypothalamic CRH expression have been suggested to influence HPA axis activity during chronic AT1 blockade. This study was aimed at confirming the role of central angiotensin II in regulating HPA reactivity by using the transgenic rat TGR(ASrAOGEN), a model featuring low levels of brain angiotensinogen. Different stress tests were performed to determine HPA reactivity in TGR(ASrAOGEN) and appropriate controls. In TGR(ASrAOGEN), blood pressure was diminished compared to controls. The corticosterone response to a CRH or ACTH challenge and a forced swim test was more distinct in TGR(ASrAOGEN) than it was in controls and occurred independently of a concurrent enhancement in ACTH. Using quantitative real-time PCR, we found increased mRNA levels of melanocortin 2 (Mc2r) and AT2 receptors (Agtr2) in the adrenals of TGR(ASrAOGEN), whereas mRNA levels of Crh, Pomc, and AT1 receptors (Agtr1) remained unchanged in hypothalami and pituitary glands. Since stress responses were increased rather than attenuated in TGR(ASrAOGEN), we conclude that the reduced HPA reactivity during AT1 blockade could not be mimicked in a specific transgenic rat model featuring a centrally inactivated renin–angiotensin–aldosterone system. The ACTH independency of the enhanced corticosterone release during CRH test and the enhanced corticosterone response to ACTH rather indicates an adrenal mechanism. The upregulation of adrenal MC2 and AT2 receptors seems to be involved in the stimulated facilitation of adrenal corticosterone release for effectuating the stimulated stress responses.
Effects of fine aggregate on the properties of calcium phosphate cements
Authors: Sturgeon J.L. , Allcock H.R. , Nair L. , Laurencin C.T. , Brown P.W.
Published: October 2009

The effects of the presence of carbonate and calcium phosphate aggregate on the mechanical properties of calcium phosphate cements were explored. Calcium phosphate precursors reacted to form hydroxyapatite at the binder phase. The effects on mechanical properties correlated with the quality of the interfacial bond developed. CaCO3 and 3CaO.P2O5 aggregates are not inert when constituted with calcium phosphate cement and are consumed with time. Mechanical properties and paste microstructure also showed a dependence on the composition of the mixing solution. NaHCO3 dissolved in the mixing solution reacts to form a carbonated hydroxyapatite and this resulted in changes in both compressive strength and morphology.
The Relationship Between Dating Violence and Psychosocial Problems in a Sample of Adolescent Pregnancy Termination Patients
Authors: Ely Gretchen E. , Nugent William R. , Flaherty Chris
Published: October 2009

The relationship between dating violence and 13 psychosocial problems, conceptually organized into three symptom clusters—depressive, family problem, and posttraumatic stress—was investigated in a sample of adolescent pregnancy termination patients, ages 14 to 21. Results of a multivariate multiple-regression analysis indicated that, after controlling for age, ethnicity, general aggression problems, and problems with peers, dating violence was significantly related with the symptoms clusters. At the univariate level, the results suggested that dating violence was significantly related with self-esteem problems, guilt, and suicidal thinking from the depressive symptoms cluster and with guilt and stress from the posttraumatic stress cluster. The implications of these findings are discussed.
The Domestic Violence Home-Visit Intervention: Impact on Police-Reported Incidents of Repeat Violence Over 12 Months
Authors: Stover Carla Smith , Poole Gina , Marans Steven
Published: October 2009

The domestic violence home-visit intervention (DVHVI) provides home visits by police-advocate teams within 72-hours of domestic incident to provide safety, psychoeducation, mental health, legal, or additional police assistance. Clinical and police record data were collected for 512 cases, and repeat calls to the police were tracked for 12 months. Analyses revealed that women who engaged with the DVHVI were more likely to contact the police for subsequent events than those who received no or minimal DVHVI contact. Hispanic women served by Spanish-speaking advocate-officer teams were the most likely to utilize services and call the police for subsequent incidents.
Resource Loss as a Predictor of Posttrauma Symptoms Among College Women Following the Mass Shooting at Virginia Tech
Authors: Littleton Heather , Grills-Taquechel Amie , Axsom Danny
Published: October 2009

We examined risk factors for posttrauma symptomatology, 2 and 6 months following the April 2007 mass shooting at Virginia Tech. Using a conservation of resources framework and a Web-based survey methodology, we prospectively evaluated the relations among preshooting distress, social support, resource loss, and posttrauma symptomatology in a sample of 293 female students enrolled at the university at the time of the shootings. Structural equation modeling supported that preshooting social support and distress predicted resource loss postshooting. Resource loss predicted symptomatology 2 months and 6 months after the shooting. Implications of the results for research and intervention following mass trauma are discussed.
The Long-Term Effects of Extreme War-Related Trauma on the Second Generation of Holocaust Survivors
Authors: Gangi Sarah , Talamo Alessandra , Ferracuti Stefano
Published: October 2009

The psychological consequences of intergenerational trauma on the second generation of Holocaust survivors were studied in a sample of 40 nonimmigrant Italian Jews and compared to a control group. Differences between offspring of Holocaust survivors (HSO) and a comparison group were assessed by the Adjective Check List, Anxiety Questionnaire Scale, Defence Mechanism Inventory, and Family Environment Scale. Although the HSO displayed no serious psychological consequences, they had higher anxiety levels than controls, low self-esteem, inhibition of aggression, and relational ambivalence. These data partially confirm previous research on the topic, although the level of psychological distress seems to be lower in the Italian sample than in other samples of second-generation Holocaust survivors.
Vibration Monitoring System Using Wireless Technology: A Feasible Alternative Solution for Noncritical Machines
Authors: Alhetairshi Mishaal Awwadh
Published: October 2009

Wireless condition monitoring technology uses wireless sensor interface modules to collect vibration and temperature data from assets scattered around the plant and send the data to a diagnostic software platform. It has multiple channels for vibration and temperature. Additional wireless sensors are often required to function as "Repeaters" to strengthen the wireless signal and provide redundant pathways.

It is a feasible alternative to handheld or hardwired condition monitoring systems, particularly attractive for essential machines, which do not require real-time machinery protection but demand a more frequent monitoring rate than the portable regime to detect potential failure modes. This technology is also useful for applications, which are logistically difficult or hazardous to monitor by handheld data collectors, or require more frequent sampling than the walk-around route can economically support.

The report begins by introducing the wireless condition monitoring system's different components and how each of them operates. Then, the setup of the field trial is explained with the stated objectives. The report is aided continuously, with tables and figures to help illustrate the technology and the method of the field trial. Following that, a comparison between handheld data collector and wireless sensor data was done to validate the collected data. Finally, the report concludes with a summary of the results of the wireless condition monitoring field trial.
Case History Summary: Horizontal Drilling Performance Improvement Due to Torque Rocking on 800 Horizontal Land Wells Drilled for Unconventional Gas Resources
Authors: Maidla Eric Edgar , Haci Marc , Wright Daniel
Published: October 2009

The torque rocking technology1,2 that will be discussed here is a surface system (nothing ever goes down hole) that has shown to greatly increase the efficiency of steerable motors (by as much as 294%) as will be demonstrated in the case history summary.

This paper summarizes for the first time the lessons learnt from using a horizontal drilling technology introduced 6 years ago that has drilled over 800 horizontal wells in several different plays in the US related to unconventional gas resources, namely the Barnett Shale, the Haynesville Shale, the Marcellus Shale, the Fayetteville Shale.

The common thread here is that all these wells were drilled with a new torque rocking technology that greatly enhances slide drilling by breaking drag using a rocking motion imposed by the topdrive (oscillatory movements to the right and left while sliding) using torque as the basic feedback mechanism to control the rocking movement.

This paper focuses on the value added benefit of this technology and areas in which it has worked and hasn't worked. A matrix has been developed to help the selection of the technology and the physics of the process are further explained to justify the improvements and failures.

Improvements included: sliding ROP increases between 20% to 294%; downhole bottom tool face orientation (unique to this technology); stalling avoidance that greatly increased the life of the downhole equipment (motors, bits, MWD) that led to less trips.
A Comprehensive Modeling Analysis of Borehole Stability and Production Liner Deformation for Inclined/Horizontal Wells Completed in a Highly Compacting Chalk Formation
Authors: Furui K. , Fuh G.-F. , Abdelmalek N. , Morita N.
Published: October 2009

Numerous casing and production liner deformation/failure problems have been reported in high porosity chalk formations in both the overburden and the reservoir sections, causing costly operation problems that prevent workovers and recompletions. This paper presents the results of studies performed to investigate stability of an openhole, cemented liner, and uncemented liner completions in a highly compacting chalk formation. The effects of critical cavity dimensions caused by various acid stimulation techniques were also investigated.

Based on the review of historical caliper survey data, we ascertain that the axial compression collapse is a major liner deformation mechanism in the reservoir zones. Axial compression collapse has been found in both low-angle wells (also buildup sections of horizontal wells) and horizontal laterals. The casing deformation in low-angle sections are due to reservoir compaction (i.e., change in the vertical formation strain) while the deformation in horizontal sections are primarily induced by increased axial loading due to cavity deformation. The current completion practice using cluster perforations and high volume acid treatments causes vertically enlarged cavities resulting in poor radial constraint.

A series of laboratory triaxial tests were performed on selected reservoir chalk samples to measure the stress-strain and failure behavior of the chalk formation considering a wide range of porosity, water saturation, and different levels of confining pressures. Using the chalk failure criteria and constitutive relations developed from the analysis of laboratory triaxial compression test data, a 3D non-linear poroelastic-plastic finite element model was developed for the openhole stability analysis. The simulation results show that the abnormally high ductility of chalks after pore collapse around a borehole could actually enhance borehole stability with the magnitude beyond expectation.

In this study, the analytical and numerical models are also developed for evaluating cavity-induced axial compression collapse of production liners. Model results indicate that the risk of the cavity-induced axial compression collapse substantially increases for short perforated intervals stimulated with large acid treatments. However, increasing the perforation interval lengths along the entire liner axis results in more uniform acid distribution and will greatly reduce the chance of axial compression collapse caused by localized cavity deformation. Based on these analysis results, key completion design criteria and stimulation strategies were developed for wells completed in highly compacting chalk reservoirs to reduce risk of casing and liner mechanical problems.
Dynamic Updating of Reservoir Models
Authors: Ates Harun , Bahar Asnul , Krasnov Vitaly , Kelkar Mohan
Published: October 2009

In sandstone reservoirs, one of the most important challenges is the effective upscaling of a fine scale model. A conventional upscaling process is not adequate when significant percentage of shale distribution exists in the reservoir. In the fine scale model, significant discontinuity exists in sand bodies. Some sand bodies are connected to the wells, and some are not. As the fine scale model is upscaled, some discontinuous sand bodies are combined with other connected sands. This results in two potential problems: the connected volume to the existing wells increases, thus making the production from those wells more optimistic, and the production from in fill wells do not show as much additional potential since some of the new volumes which should have been connected to the new well are already drained by the existing wells.

A new procedure1 is developed to overcome this problem. In a new procedure, we first determine the connected sand volume to the existing wells. We remove the dis-connected sand bodies from the fine scale model. We then upscale the model to a desired level. We simulate the flow performance till a desired time when either new wells are drilled or some well are shut-in. At that point, we start from the fine scale model again and determine new connected volume due to additional of new wells. We combine the new virgin sands with depleted sands in the upscaled model and determine the saturation and pressure in the upscaled model using an appropriate material balance technique. We re-start the simulation using newly connected volume till we reach a point of drilling additional wells. The key difference between the proposed method and the existing methods, is our ability to add new hydrocarbon volumes (as well as new conductivity) in the model as a function of time.

The proposed method was applied to a giant oil field in Siberia which is in turbite environment with large amounts of discontinuous sand bodies. We were able to demonstrate the advantage of the proposed method by comparing the performance of upscaled simulation model to the fine scale geologic model. As the percentage of sand decreases in a given reservoir, the difference between the conventional and a proposed method becomes significant. Using the new approach, we would be able to evaluate the infill potential much more accurately.
Fuzzy Analysis of ESP System Performance
Authors: Thornhill Donald G. , Zhu David
Published: October 2009

The purpose of this paper is to illustrate how Fuzzy Logic, along with some expert knowledge of how an electrical submersible pumping system (ESP) performs, can be used to provide near real-time diagnostics using a limited number of signals typically acquired from an ESP system. Common problems in a running ESP system can be diagnosed by examining patterns in the measured data compared to values associated with a system that is operating normally. Using Fuzzy Logic, patterns associated with specific problems can be detected long before they become obvious. This information can be used to respond to emerging conditions before they result in downtime, or can identify why a system is not performing as expected. This analysis is applicable to ESP systems operating in a stable state, where normal measurement ranges can be determined. It is not intended to diagnose problems during system startup or when outside factors are dynamically altering well performance.
A Novel Approach of Wireline Intervention for Newly Drilled Well: Sotong Case Study and Best Practices
Authors: Razak M. Hairi A , Hashim M. S. , Ali Zulkifli , Ezalina Nurul
Published: October 2009

Sotong-A9 was drilled in dual completion. Maximum target production is 3000 bbl/d for the long string while short string capable to produce 20 mmscd. Sotong platform was the highest producer for MASA field located about 135 km offshore Terengganu which comprises of Malong, Anding and Sotong. Currently all the produced oil and gas is process and store on FPSO facilities located nearby.

During completion stages an "unknown" fish was left in hole thus hindering wireline intervention to open SSD to unload zone below the fish depth. Total potential reserve for both zones is estimate 20 million barrel of oil. Due to that, wireline operation to retrieve the fish was considered critical due of fear for leaving the zone with completion fluid can damages the formation.

There were 2 wells included in the infill drilling campaign. Any delay due to fishing job can contribute to higher rig cost. Prior to actual job execution, few main challenges need to properly addressed such as job coordination/people management, well pressure control and slickline equipment rig up complexity.

Therefore, while the drilling continue in Stg-03 well, slickline intervention for fishing operation was continue at well Stg-09L with the 21-1/4" conductor BOP still attached on it. Slickline lubricator is rig-up on top of the existing BOP prior to fishing job and pressure test was carried out to ensure the well pressure containment. This novel technique contributed to cost saving of USD 400K due to no requirement for rig standby for conductor BOP removal.

This paper discussed on best practices of rig up wireline in existing drilling BOP, Job Hazard Analysis (JHA), job procedures and lesson learned.
Cleanup Acid System for Gravel-Pack Completions Without Increasing Water Production
Authors: Barragan Ernesto , Serrano Fabrizio , Cayo Marco , Ramirez Cristian , Martinez Carlos
Published: October 2009

Gravel-pack (GP) completions are used on formations presenting sand-production problems worldwide. The inherent problem with this type of completion is its tendency to become plugged as a result of fines migration, solids invasion, and emulsion problems, which are the most commonly damaged mechanisms affecting productivity.

Pumping acid systems is an effective method to solve GP plugging problems but usually results in increased post-treatment water production. Acid will enter zones with higher water saturations, which often are higher permeability, and causes operational problems, such as decreased oil production and increased lifting costs. Historically, various methods for diverting fluids have been used. These methods included the use of viscous fluids, degradable particles, ball sealants and foam.

Recently, relative permeability modifiers (RPM) have been used successfully as a diversion system for acid systems to decrease the relative permeability to water. Customized application to clean up GP completions is the presented solution.

This paper describes the use of RPM diversion systems that reduce the formation's permeability to water without significant effects on permeability to hydrocarbons. Four GP wells that were treated with this system, resulting in increased hydrocarbon production without increasing water production, are presented in detail.

The four wells discussed are located in the same reservoir in Oriente Basin, onshore Ecuador. Wells are placed in formation M-1 Tarapoa Oilfield, which is an unconsolidated sand formation. Sand production has occurred in some of the oil producers. Wells are generally completed with GP screens with sand being pumped to fill the perforations and the wellbore x screen annulus. Well A8 was the first well treated with the acid system diverted with an RPM. Well A8 had a production decline caused by GP plugging, which also affected the ESP equipment performance. After the treatment the well productivity was restored successfully. It was decided to treat three more wells in the same reservoir. These treatments also resulted in a gain in production.
Naturally Fractured Reservoir Three-Dimensional Analytical Modeling: Theory and Case Study
Authors: Nguyen Vinh X. , Abousleiman Younane N.
Published: October 2009

Natural fractures play an important role in the technical and economic performance of all hydrocarbon producing reservoirs. Generally, the presence of fractures weakens the reservoir mechanically and produces higher permeability fluid flow paths within the low permeability rock formation. In reservoir simulation, the intricate interplay between reservoir compaction and fluid flow may lead to undesirable production behavior if the effects of fractures are not properly accounted for. Due to the complexity of the physical phenomena and mathematical formulations, all naturally fractured reservoir modelings are performed numerically using discrete fracture network, finite difference and/or finite element method. While geologically realistic and practical, these numerical methods are computationally intensive and require analytical validation. These facts necessitate a dual-porosity and dual-permeability approach to analytical modeling that incorporates time-dependency and fracture networks effects on reservoir performance.

In this work, a general anisotropic dual-porosity and dual-permeability analytical formulation is presented to simulate naturally fractured reservoir accounting for fractures deformation and fluid flow in a three dimensional state of stresses. The solution is applied to simulate reservoir compaction of a fractured reservoir in the Ghawar field, Saudi Arabia. It is helpful in the estimation of time-dependent induced local permeability alteration due to wellbore production/injection. Various scenarios of fractures representations are illustrated to highlight the impacts of fractures’ orientations, density, porosity and permeability on the overall reservoir response. In addition, the solution for the effective stress changes in the reservoir can be used to estimate stress on pipe/casing and formation brittle failure that precedes solid production.

Analyses reveal that production may induce up to 7-percent permeability reduction which can affect the production rate. Thus, accounting for reservoir compaction facilitates future production forecast and/or stimulation planning. For a vertical well, horizontal fractures orientation show higher degree of compaction and permeability damage than vertically oriented fractures. Discounting the effect of fractures will largely underestimate the decline in reservoir performance and complicate future field-development options.

This unique analytical model and solution can be directly applied to real field analyses in naturally fractured reservoirs. The impact of fractures on the overall reservoir performance can be investigated using the solution and approach presented. Finally, the analytical solution can be used as a benchmark for validation of available reservoir simulation numerical codes.