bluuebunny/crossref_metadata_2025 huggingface dataset:
Complete Pathologic Response After Preoperative Chemotherapy for Colorectal Liver Metastases: Myth or Reality?
Authors: Adam René , Wicherts Dennis A. , de Haas Robbert J. , Aloia Thomas , Lévi Francis , Paule Bernard , Guettier Catherine , Kunstlinger Francis , Delvart Valérie , Azoulay Daniel , Castaing Denis
Published: March 2008

Purpose

Complete clinical response (CCR) of colorectal liver metastases (CLM) following chemotherapy is of limited predictive value for complete pathologic response (CPR) and cure of the disease. The objective of this study was to determine predictive factors of CPR as well as its impact on survival.

Patients and Methods

From January 1985 to July 2006, 767 consecutive patients with CLM underwent liver resection after systemic chemotherapy. Patients with CPR were compared with patients without CPR.

Results

Twenty-nine of 767 (4%) patients had CPR, and none of these 29 patients had CCR. Patients with CPR (mean age, 54 years) had a mean number of 3.3 metastases at diagnosis (mean size, 29.3 mm). Objective response and stable disease were observed in 79% and 21% of cases, respectively. Postoperative mortality rate was 0%. After a median follow-up of 52.2 months (range, 1.1 to 193.0 months), overall 5-year survival was 76% for patients with CPR compared with 45% for patients without CPR (P = .004). Independent predictive factors for CPR were: age ≤ 60 years, size of metastases ≤ 3 cm at diagnosis, carcinoembryonic antigen (CEA) level at diagnosis ≤ 30 ng/mL, and objective response following chemotherapy. The probability of CPR ranged from 0.2% when all factors were absent to 30.9% when all were present.

Conclusion

CPR was observed in 4% of patients with CLM treated with preoperative chemotherapy. However, CPR may occur in almost one-third of objective responders age ≤ 60 years with metastases ≤ 3 cm and low CEA values. CPR is associated with uncommon high survival rates.
Easing of Suffering in Children With Cancer at the End of Life: Is Care Changing?
Authors: Wolfe Joanne , Hammel Jim F. , Edwards Kelly E. , Duncan Janet , Comeau Michael , Breyer Joanna , Aldridge Sarah A. , Grier Holcombe E. , Berde Charles , Dussel Veronica , Weeks Jane C.
Published: March 2008

Purpose

In the past decade studies have documented substantial suffering among children dying of cancer, prompting national attention on the quality of end-of-life care and the development of a palliative care service in our institutions. We sought to determine whether national and local efforts have led to changes in patterns of care, advanced care planning, and symptom control among children with cancer at the end of life.

Methods

Retrospective cohort study from a US tertiary level pediatric institution. Parent survey and chart review data from 119 children who died between 1997 and 2004 (follow-up cohort) were compared with 102 children who died between 1990 and 1997 (baseline cohort).

Results

In the follow-up cohort, hospice discussions occurred more often (76% v 54%; adjusted risk difference [RD], 22%; P < .001) and earlier (adjusted geometric mean 52 days v 28 days before death; P = .002) compared with the baseline cohort. Do-not-resuscitate orders were also documented earlier (18 v 12 days; P = .031). Deaths in the intensive care unit or other hospitals decreased significantly (RD, 16%; P = .024). Parents reported less child suffering from pain (RD, 19%; P = .018) and dyspnea (RD, 21%; P = .020). A larger proportion of parents felt more prepared during the child's last month of life (RD, 29%; P < .001) and at the time of death (RD, 24%; P = .002).

Conclusion

Children dying of cancer are currently receiving care that is more consistent with optimal palliative care and according to parents, are experiencing less suffering. With ongoing growth of the field of hospice and palliative medicine, further advancements are likely.
Automated visual tracking for studying the ontogeny of zebrafish swimming
Authors: Fontaine Ebraheem , Lentink David , Kranenbarg Sander , Müller Ulrike K. , van Leeuwen Johan L. , Barr Alan H. , Burdick Joel W.
Published: March 2008

The zebrafish Danio rerio is a widely used model organism in studies of genetics, developmental biology, and recently, biomechanics. In order to quantify changes in swimming during all stages of development, we have developed a visual tracking system that estimates the posture of fish. Our current approach assumes planar motion of the fish, given image sequences taken from a top view. An accurate geometric fish model is automatically designed and fit to the images at each time frame. Our approach works across a range of fish shapes and sizes and is therefore well suited for studying the ontogeny of fish swimming, while also being robust to common environmental occlusions. Our current analysis focuses on measuring the influence of vertebra development on the swimming capabilities of zebrafish. We examine wild-type zebrafish and mutants with stiff vertebrae (stocksteif) and quantify their body kinematics as a function of their development from larvae to adult (mutants made available by the Hubrecht laboratory, The Netherlands). By tracking the fish, we are able to measure the curvature and net acceleration along the body that result from the fish's body wave. Here, we demonstrate the capabilities of the tracking system for the escape response of wild-type zebrafish and stocksteif mutant zebrafish. The response was filmed with a digital high-speed camera at 1500 frames s–1. Our approach enables biomechanists and ethologists to process much larger datasets than possible at present. Our automated tracking scheme can therefore accelerate insight in the swimming behavior of many species of (developing)fish.
Three-dimensional flow structures and evolution of the leading-edge vortices on a flapping wing
Authors: Lu Yuan , Shen Gong Xin
Published: March 2008

Following the identification and confirmation of the substructures of the leading-edge vortex (LEV) system on flapping wings, it is apparent that the actual LEV structures could be more complex than had been estimated in previous investigations. In this experimental study, we reveal for the first time the detailed three-dimensional (3-D) flow structures and evolution of the LEVs on a flapping wing in the hovering condition at high Reynolds number(Re=1624). This was accomplished by utilizing an electromechanical model dragonfly wing flapping in a water tank (mid-stroke angle of attack=60°) and applying phase-lock based multi-slice digital stereoscopic particle image velocimetry (DSPIV) to measure the target flow fields at three typical stroke phases: at 0.125T (T=stroke period), when the wing was accelerating; at 0.25T, when the wing had maximum speed; and at 0.375T, when the wing was decelerating. The result shows that the LEV system is a collection of four vortical elements: one primary vortex and three minor vortices, instead of a single conical or tube-like vortex as reported or hypothesized in previous studies. These vortical elements are highly time-dependent in structure and show distinct `stay properties' at different spanwise sections. The spanwise flows are also time-dependent, not only in the velocity magnitude but also in direction.
Visual sensitivity to a conspicuous male cue varies by reproductive state inPhysalaemus pustulosusfemales
Authors: Cummings Molly E. , Bernal Ximena E. , Reynaga Roberto , Rand A. Stanley , Ryan Michael J.
Published: March 2008

The vocal sac is a visually conspicuous attribute of most male frogs, but its role in visual communication has only been demonstrated recently in diurnally displaying frogs. Here we characterized the spectral properties of the inflated vocal sac of male túngara frogs (Physalaemus pustulosus), a nocturnal species, and túngara visual sensitivity to this cue across reproductive state and sex. We measured the spectral and total reflectance of different male body regions, including inflated and non-inflated vocal sacs, along with samples of the visual background against which males are perceived. Inflated vocal sacs were the most reflective of all body parts, being one log unit more reflective than background materials. We utilized an optomotor drum with black stripes and stripes that mimicked the spectral reflectance of the inflated vocal sacs with various nocturnal light intensities to measure the visual sensitivity thresholds of males,non-reproductive females and reproductive females. All three groups exhibited visual sensitivities corresponding to intensities below moonless conditions in open habitats or at the edge of secondary tropical forests. Reproductive females exhibited the greatest visual sensitivity of all groups, and were significantly more sensitive than non-reproductive females. Though the mechanism for this physiological difference between reproductive and non-reproductive females is unknown, it is consistent with previously observed patterns of light-dependent phonotaxic behavior in túngaras. We suggest that the visual ecology of the vocal sac, especially in nocturnal frogs,offers a rich source for investigations of visual ecology and physiological regulation of vision.
Cold induced changes of adenosine levels in common eelpout (Zoarces viviparus): a role in modulating cytochromecoxidase expression
Authors: Eckerle L. G. , Lucassen M. , Hirse T. , Pörtner H. O.
Published: March 2008

Exposure of ectothermic organisms to variations in temperatures causes a transient mismatch between energy supply and demand, which needs to be compensated for during acclimation. Adenosine accumulation from ATP breakdown indicates such an imbalance and its reversal reflects a restoration of energy status. We monitored adenosine levels in blood serum and liver of common eelpout (Zoarces viviparus) during cold exposure in vivo. Furthermore, we tested its effect on the pattern of thermal acclimation in hepatocytes isolated from cold- (4°C) versus warm- (11°C) exposed fish. Adenosine levels increased during cold exposure in vivo and reached a transient maximum after 24 h in serum, but remained permanently elevated in liver. Whole animal cold acclimation induced a rise of liver citrate synthase activity by 44±15%, but left cytochrome c oxidase activity (COX) and RNA expression of the respective genes unchanged. Cold incubation of hepatocytes from warm-acclimated fish failed to cause an increase of mitochondrial enzyme activities despite increased COX4 mRNA levels. Conversely, warm acclimation of hepatocytes from cold-acclimated fish reduced both enzyme activities and COX2 and COX4 mRNA levels by 26–37%. Adenosine treatment of both warm- and cold-acclimated hepatocytes suppressed COX activities but activated COX mRNA expression. These effects were not receptor mediated. The present findings indicate that adenosine has the potential to regulate mitochondrial functioning in vivo, albeit the pathways resulting in the contrasting effects on expression and activity need to be identified.
Cuticular hydrocarbons as queen adoption cues in the invasive Argentine ant
Authors: Vásquez Gissella M. , Schal Coby , Silverman Jules
Published: March 2008

In social insects, individuals typically recognize and behave aggressively towards alien conspecifics, thereby maintaining colony integrity. This is presumably achieved via a nestmate recognition system in which cuticular compounds, usually cuticular hydrocarbons (CHC), of genetic and/or environmental origin serve as recognition cues. Most invasive populations of the Argentine ant, Linepithema humile (Mayr), display minimal nestmate–non-nestmate discrimination, resulting in low levels of intraspecific aggression allowing free movement of workers and queens among nests. However, invasive L. humile in the southeastern United States show relatively high levels of intraspecific aggression, and selectively adopt non-nestmate queens. Using behavioral assays and gas chromatography, we found an association between non-nestmate queen adoption and similarity of the CHC profiles of adopted and host colony queens. Also, nestmate and non-nestmate queen CHC profiles became more similar after adoption by queenless colonies. Furthermore, queens treated with non-nestmate queen CHC had distinct CHC profiles and were generally attacked by nestmate workers. We suggest that in L. humile, CHC are used as queen recognition cues, and that queen recognition errors are more likely to occur when the CHC profiles of non-nestmate and host colony queens are similar. Our findings provide further evidence for the complex and dynamic nature of L. humile nestmate discrimination, which may in part underlie the success of introduced populations of this invasive ant.
Breaches in good regulatory practice – the HFEA policy on compensated egg sharing for stem cell research
Authors: Devaney S
Published: March 2008

The Human Fertilization and Embryology Authority policy on permitting ova provision for research purposes breaches good regulatory practice in being inconsistent, unaccountable and untargeted. This article will illustrate how these breaches have resulted in a policy which is unfair to ova providers who wish to contribute to stem cell research and undermines the intentions behind the policy's very inception. (This article is based on a paper entitled Appropriate Recompense for Oocytes in Stem Cell Research presented at the Stem Cells: Hope or Hype debate, North West Genetics Knowledge Park, Manchester in May 2007.)
Labioplasty in girls under 18 years of age: an unethical procedure?
Authors: Boraei S , Clark C , Frith L
Published: March 2008

Labioplasty is a surgical procedure performed to alter the size and shape of the labia minora. The reasons for women requesting this procedure remain largely unknown and recently girls and young women under the age of 18 years have been requesting this type of surgery. This paper examines the ethical acceptability of performing this procedure on under 18s. We will first discuss whether labioplasty can be considered to be a therapeutic technique. We will claim that, while it is difficult to offer a definitive definition of what constitutes a therapeutic technique, in our view labioplasty cannot be considered as such. This conclusion has relevance for the ethical acceptability of the procedure, its legal status in regard to the Female Genital Mutilation Act and the debates over who can give consent for it. It will be concluded that in our current state of knowledge, the benefits of labioplasty are far from clear, whereas the harms are demonstrable and therefore this procedure should not be offered to those aged under 18 years.
To what extent does medical device maintenance pose clinical risk?
Authors: Brown Anthony Scott
Published: March 2008

Healthcare is a risky business and patient safety is afforded a high profile. Although great lengths are taken to ensure medical devices are intrinsically safe, risks can occur when they are introduced into the clinical setting. A risk assessment tool, Medical Device Risk Assessment (MeDRa) was used to collect quantitative data relating to the contributory factors and control measures associated with using medical devices in the clinical setting. The tool utilizes the responses from healthcare professionals to a set of questions about risk as a basis for the risk assessment. The raw data was exported to SPSS for statistical analysis and mathematical modelling. Pearson's Chi-square tests for association and relative risk calculations formed the basis for the analysis. This paper reports on one aspect of the risk assessment relating to the maintenance of medical devices. There are two categories of maintenance: technical and user maintenance. The analysis showed that although there was a high level of conformity in technical maintenance, user maintenance was highlighted as a potential problem. MeDRa identifies potential risk factors that might impact on patient care.
Neonatal resuscitation – the team needs a leader
Authors: Plaat Felicity
Published: March 2008

Training in neonatal resuscitation is mandatory for any healthcare professional that may be present at delivery. This includes midwives, obstetrician and anaesthetists as well as paediatricians. The cornerstone of neonatal resuscitation is the establishment of a patent airway to allow lung inflation. In the absence of a patent airway, all other resuscitative manoeuvres are ineffective. Adherence to resuscitation guidelines, regular re-training and effective team leadership are necessary for succcesful resuscitation.
Trial of forceps – legal aspects
Authors: Spencer Martin
Published: March 2008

Where an obstetrician attempts a forceps delivery on the labour ward, rather than as a ‘Trial of Instrumental Delivery’ in theatre with the mother fully prepared for Caesarean section, he will have the burden of justifying his actions where he fails to deliver the baby, precipitates an acute bradycardia and is unable to deliver by Caesarean section before permanent brain damage ensues. The Bolitho test will apply to experts judging the question: was the Obstetrician's decision defensible having regard to the comparative risks and benefits? See Kingsberry [2005] EWHC (QB) 2253. Even where an obstetrician correctly decides to carry out a Trial of Operative Delivery, in theatre, he must not delay unreasonably in converting to Caesarean section when an acute bradycardia is precipitated. He should bear in mind the ‘10-minute rule’: Purver v Winchester & Eastleigh NHS Trust [2007] LS Law Med 193.
Influence of antiretroviral treatment on quality of life in seropositive inmates
Authors: Del Castillo L Sordo , Ruiz-PÉRez I , De Labry-Lima A Olry , Soto-Blanco J M , Girela-LÓPez E , Castro-Recio J M , Antón-Basanta J J
Published: March 2008

Summary

The aim of the study is to evaluate the influence of antiretroviral treatment on health-related quality of life (HRQOL) of three groups of HIV-positive inmates: those who are taking antiretroviral treatment, those who are not on treatment as it has not yet been indicated, and those who refuse to take treatment even though it has been recommended. A cross-sectional study was conducted on 585 HIV+ inmates in three prisons. The response variable was HRQOL. Independent variables were: sociodemographic variables, psychosocial and drug-related variables. Two multivariate linear regression models were constructed in order to determine the HRQOL, physical health score (PHS) and mental health score (MHS), for each of the three groups identified, using patients who refused treatment as the reference category. Patients who refused therapy had a lower MHS compared with patients in whom treatment was not indicated (P = 0.038). With regard to PHS, patients refusing therapy had a lower score than patients who were not indicated therapy (P = 0.005), and than patients receiving therapy (P = 0.010).
Prevalence and factors associated with anal lesions mediated by human papillomavirus in men with HIV/AIDS
Authors: Pereira A , Lacerda H R , Barros R R
Published: March 2008

Summary

Prevalence and risk factors for human papillomavirus-related anal lesions were evaluated in 60 men with human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS). Patients underwent anal cytology, anuscopy under colposcopic vision and anal biopsy for detection of the lesions. The mean age was 41.9 years and the mean time of HIV infection was 6.8 years, 88.3% of them having been on highly active antiretroviral therapy for an average of 6.5 years. Homosexuals represented 43.3% and bisexuals 15.0% whereas heterosexuals comprised 41.7%. The prevalence of anal lesions detected by anuscopy under colposcopic vision, cytology and biopsy were, respectively, 35.0, 16.7 and 23.3%. Homosexuals or bisexuals accounted for 85.7% of the patients with an abnormal biopsy, the remaining 14.3% being heterosexuals (P = 0.02). The T-CD4+ lymphocyte count, HIV viral load and use of antiretrovirals did not reveal any association with anal lesions. The occurrence of anal lesions was high in the individuals with HIV/AIDS, especially in the homosexuals and bisexuals, but it also occurred in heterosexuals, justifying the screening of anal lesions of all men with the infection.
Improved injection network ascertainment with supplementary elicitation techniques
Authors: Brewer Devon D , Hagan Holly , Hough Eileen S
Published: March 2008

Summary

Prior research indicates that injection drug users forget substantial proportions of their injection partners when asked to recall them. Such under-reporting hampers both ascertainment of the injection networks that underlie transmission of blood-borne pathogens and contact-tracing efforts for disease control. We report here an evaluation of supplementary elicitation techniques – a set of prompting strategies and recall cues – employed in a study that involved tracing of injection partners. Sixty-one index drug injectors in Seattle participated in the study. The supplementary partner elicitation techniques enhanced recall of injection partners substantially and identified persons relevant to transmission of blood-borne pathogens. As a set, the supplementary techniques elicited additional partners from 70% of injectors, and the additional partners elicited represent a 75% increase on average. Drug injectors who recalled many partners before administration of the supplementary techniques tended to report more additional partners in response to the supplementary techniques than injectors who freely recalled few partners. In addition, partners elicited by the supplementary techniques were as likely as freely recalled partners to test positive for hepatitis C virus antibody and engage in risk behaviour with indexes. Furthermore, we found that the supplementary techniques boosted connectivity in the observed injection network considerably.
An educative genitourinary medicine clinic website: value to users and impact on service demand
Authors: Basta Medhat S T , Hussey Jane , Pattman Richard S , Sankar K Nathan
Published: March 2008

Summary

In 2004, the Newcastle genitourinary medicine clinic launched a new website. To assess its value to users and impact on service demand, we surveyed those attending the clinic with a new episode between September and December 2005 by a questionnaire. One hundred and fifteen of 601 respondents (19%) visited the website. Fifty-nine percent of users were men with those aged between 35 and 44 ranking the highest percentage (31.7%) among those who visited the website. Fourteen (12.5%) would not have attended if they had not visited the website. One hundred and two (88.7%) found it easy to use and 81 (70.4%) looked for specific information of whom 73 (89%) were successful. Web users were more likely to present with an episode not requiring treatment possibly indicating increased demand promoted by our prevention information but less likely to have bacterial vaginosis, anaerobic balanitis and anogenital candidosis (not statistically significant).
HIV-related knowledge and stigma among high school students in Libya
Authors: El-Gadi Saleh , Abudher Abdulhafid , Sammud Mohamed
Published: March 2008

Summary

This study aims to measure indicators of HIV-related stigma among students of high schools in the North West of Libya. The results will be part of baseline data and evaluation of the impact of successive interventions. Understanding the behaviour of risk groups in a society, such as young people, is essential in order to draw effective prevention strategies. Behavioural surveillance surveys have been shown to make an important and useful contribution to informing the response to HIV. This study was part of a large Knowledge, Attitude, Beliefs and Practice survey. A self-administrated questionnaire method was used. The response rates were high (83–92%). Despite high level of stigma shown by both boys and girls in the study, 91% of students supported providing free care to HIV infected individuals. The HIV intervention programmes for young people should operate within a comprehensive strategy to combat HIV/AIDS. The stigmatizing and the discriminatory perceptions of HIV infected individuals should be addressed as part of the education campaign.
Fulminant autoimmune hepatitis after successful interferon treatment in an HIV–HCV co-infected patient
Authors: Coriat Romain , Podevin Philippe
Published: March 2008

Summary

Hepatitis C (HCV) treatment using interferon-α (IFN-α) and ribavirin is recommended in HIV/HCV co-infected patients to prevent liver cirrhosis and liver-related death. However, in addition to its antiviral activity, IFN is a pleiotropic cytokine able to synergistically amplify T-cell autoreactivity. Here, we report for the first time the induction of a subfulminant autoimmune hepatitis (AIH) after four months of a successful treatment of HCV-1b infection using peg-IFN and ribavirin, in a 48-year-old woman co-infected with HIV. Diagnosis was assessed according to the international AIH scoring system, including liver biopsy and confirmed by positive response to steroid challenge.
Does using self-completed sexual history questionnaires in HIV-positive men who have sex with men affect clinical outcomes?
Authors: Koch Oliver , De Silva Shamela , Edwards Simon , Peake Tabitha , George Brian , Brough Garry , Miles Kevin , Benn Paul
Published: March 2008

Summary

This audit compared sexual histories taken by self-completed questionnaires (SQ) versus the ‘gold-standard’ of ‘traditional’ face-to-face interviews by health-care professionals (HP). It compared reporting of symptoms and sexual behaviour and looked at outcomes in terms of diagnoses of sexually transmitted infections. SQ were at least equal to HP and might therefore be a valuable tool in streamlining services.
Are women from high-risk ethnic minority groups more likely to decline antenatal HIV screening?
Authors: Southgate J , Mital D , Stock A
Published: March 2008

Summary

Eight new cases of human immunodeficiency virus (HIV) were diagnosed in the antenatal population of Milton Keynes within the first two years of our ‘opt-out’ antenatal testing scheme; the majority (6/8) occurred in women of black African origin. Since it is suggested that individuals from high-risk groups are more likely to decline HIV testing, we were concerned that women from this high-risk ethnic group might not be accepting testing. Such a situation would increase the risk of undiagnosed HIV-positive women delivering at Milton Keynes and undermine the potential benefits of the screening programme. Retrospective review of pregnant women delivering in our area over six months was performed. Hospital obstetric and microbiology databases were analysed for results of HIV screening and ethnic origin of patients. A total of 1586 women delivered during the study period. Among the black African women 13/158 (8.2%) declined screening, compared with 120/1214 (9.8%) and 15/153 (9.8%) of white and Asian women, respectively. The high uptake of testing across all groups suggests that the policy of offering and recommending HIV screening to all women is being appropriately implemented. Black African women were more likely to have undergone screening than white or Asian women, although the differences were not statistically significant.
Primary syphilis
Authors: Eccleston Kathryn , Collins Lisa , Higgins Stephen P
Published: March 2008

Summary

Cases of syphilis have been increasing in the UK and it remains an important public health problem. Here, we provide an overview of syphilis, its presentation, diagnosis and management.
The polymicrobial hypothesis of bacterial vaginosis causation: a reassessment
Authors: Josey W E , Schwebke J R
Published: March 2008

Summary

The cause of bacterial vaginosis remains controversial. The two leading hypotheses are that Gardnerella vaginalis is the specific aetiologic agent versus the polymicrobial hypothesis that G. vaginalis acts in concert with other bacteria, principally anaerobes, to produce the disease. Here we reassess the prevailing polymicrobial hypothesis, finding it conceptually problematical. No host initiating factors as postulated have been identified, nor is there conclusive evidence that G. vaginalis lacks diagnostic specificity for the disease. The polymicrobial hypothesis, presupposing a unique disruption of vaginal microecology, is inconsistent with the epidemiological profile of the syndrome, which is that of a sexually transmitted disease. The epidemiological and clinical similarities between bacterial vaginosis and trichomoniasis suggest a similar pathogenetic process; i.e., primary causation by a specific agent, with secondary anaerobic activation and resultant amine production.
Management of recurrent varices at the popliteal fossa after surgical treatment
Authors: Perrin M , Gillet Jean-Luc
Published: March 2008

Objectives

To analyze prevalence, incidence mechanisms, physiopathology, investigations, treatment techniques and results of recurrent varices at the popliteal fossa after surgery.

Methods

Published literature was analyzed as personal experience.

Results

Recurrent varices after surgery at the popliteal fossa are much less frequent than at the sapheno-femoral junction because the short saphenous vein is less often the site of incompetence and treated by surgery. Precise prevalence and incidence is unknown. An analysis of recurrences at the popliteal fossa revealed three causes: Incomplete division of the sapheno-popliteal junction (SPJ) at the terminal valve, which was incompetent at the initial surgery. The persisting reflux fills tributaries still connected to the saphenous stump; Neovascularization reconnects the popliteal vein to the superficial network with new vessels, which are valveless; Because the initial diagnoses is wrong and the incompetence involves the other veins of the popliteal fossa or arises from pelvic veins, which had not been recognized. Duplex scanning (DS) should identify the various sites of reflux and give precise anatomical and haemodynamic data. Treatment methods after recurrence at the popliteal fossa are repeat surgery, sclerotherapy or pelvic vein embolization when identified as the cause. Results provided by these different methods were analysed.

Conclusions

At present, no randomized control has given grade 1A, 1B or 2A, 2B recommendations. We recommend that ultrasound-guided foam sclerotherapy should be the treatment of choice unless DS shows an incompetent stump at the SPJ with a gross reflux filling the venous network.
Normalization of microRNA expression levels in quantitative RT-PCR assays: Identification of suitable reference RNA targets in normal and cancerous human solid tissues
Authors: Peltier Heidi J. , Latham Gary J.
Published: March 2008

Proper normalization is a critical but often an underappreciated aspect of quantitative gene expression analysis. This study describes the identification and characterization of appropriate reference RNA targets for the normalization of microRNA (miRNA) quantitative RT-PCR data. miRNA microarray data from dozens of normal and disease human tissues revealed ubiquitous and stably expressed normalization candidates for evaluation by qRT-PCR. miR-191 and miR-103, among others, were found to be highly consistent in their expression across 13 normal tissues and five pair of distinct tumor/normal adjacent tissues. These miRNAs were statistically superior to the most commonly used reference RNAs used in miRNA qRT-PCR experiments, such as 5S rRNA, U6 snRNA, or total RNA. The most stable normalizers were also highly conserved across flash-frozen and formalin-fixed paraffin-embedded lung cancer tumor/NAT sample sets, resulting in the confirmation of one well-documented oncomir (let-7a), as well as the identification of novel oncomirs. These findings constitute the first report describing the rigorous normalization of miRNA qRT-PCR data and have important implications for proper experimental design and accurate data interpretation.
Are Laboratories Reporting Serum Quantitative hCG Results Correctly?
Authors: Cao Zhimin (Tim) , Rej Robert
Published: March 2008

Background: Human chorionic gonadotropin (hCG) is a heterodimeric glycoprotein hormone that exists in multiple forms. Immunoassays commonly used in clinical laboratories measure intact hCG, total β hCG (intact hCG + hCG free β-subunit), and/or hCG free β-subunit. Measurement of serum concentrations of hCG is useful for confirmation and monitoring of pregnancy, diagnosis of trophoblastic diseases and monitoring of the efficacy of treatment, and prenatal screening. Correctly reporting results for the various forms of hCG is clinically important.

Method: We prepared samples by addition of intact hCG and hCG free β-subunit to an essentially hCG-free human serum matrix. The samples were analyzed by participant laboratories using various immunoassay methods.

Results: We identified errors in participant reporting of intact hCG results as total β hCG (9.3%; 22 of 235 laboratories) and total β hCG as intact hCG (13.1%; 8 of 61 laboratories).

Conclusions: Many factors contribute to the erroneous reporting of hCG results, including (a) the complexity of hCG molecule and confusion of nomenclature on the various forms of hCG; (b) laboratory personnel’s lack of awareness of the distinctions of the forms of hCG and failure to recognize the specificity of assays for their measurement; (c) lack of clarity and uniformity in manufacturers’ reagent labeling; and (d) most product inserts’ lack of information on the specificity of each method to the various forms of hCG.
Laboratory Assessment of HDL Heterogeneity and Function
Authors: Movva Rajesh , Rader Daniel J
Published: March 2008

Background: Plasma concentrations of HDL cholesterol (HDL-C) and its major protein component apolipoprotein (apo) A-I are strongly inversely associated with cardiovascular risk, leading to the concept that therapy to increase HDL-C and apoA-I concentrations would be antiatherosclerotic and protective against cardiovascular events. The recent failure of the drug torcetrapib, a cholesteryl ester transfer protein inhibitor that substantially increased HDL-C concentrations, has brought focus on the issues of HDL heterogeneity and function as distinct from HDL-C concentrations.

Content: This review addresses the current state of knowledge regarding assays of HDL heterogeneity and function and their relationship to cardiovascular disease. HDL is highly heterogeneous, with subfractions that can be identified on the basis of density, size, charge, and protein composition, and the concept that certain subfractions of HDL may be better predictors of cardiovascular risk is attractive. In addition, HDL has been shown to have a variety of functions that may contribute to its cardiovascular protective effects, including promotion of macrophage cholesterol efflux and reverse cholesterol transport and antiinflammatory and nitric oxide–promoting effects.

Summary: Robust laboratory assays of HDL subfractions and functions and validation of the usefulness of these assays for predicting cardiovascular risk and assessing response to therapeutic interventions are critically important and of great interest to cardiovascular clinicians and investigators and clinical chemists.
Crack Arrest Testing Using Small Wide Plate SE(T) Specimens
Authors: Link Richard E. , Roe Charles
Published: March 2008

A greatly scaled-down version of the wide plate crack arrest test has been developed to characterize the crack arrest performance of a high strength, low alloy (HSLA) steel alloy in the upper region of the ductile-brittle transition. The specimen is a single-edge notched, 152 mm wide by 19 mm thick by 910 mm long plate subjected to a strong thermal gradient and a tensile loading. The thermal gradient is required to arrest the crack at temperatures high in the transition region, close to the expected service temperature for crack arrest applications in surface ships. Strain gages are placed along the crack path to obtain crack position and crack velocity data, and this data, along with the applied loading is combined in a “generation mode” analysis using finite element analysis to obtain a dynamic analysis of the crack arrest event. A prior investigation demonstrated the feasibility of the technique and this investigation was devised to obtain a larger dataset of crack arrest toughness values of an HSLA-100 steel plate to better characterize the upper transition crack arrest performance of this alloy. Brittle crack initiation, significant cleavage crack propagation, and subsequent crack arrest was achieved in all eight of the tests conducted in this investigation. The cleavage cracks were observed to propagate at nearly constant velocity, typically in the range of 350–400 m/s before arresting abruptly. A crack arrest master curve approach was used to characterize the fracture toughness and a crack arrest reference temperature, TKIA=−136°C was determined for the HSLA-100 plate. This corresponded to a shift in the crack initiation reference temperature of +36°C. The shift in reference temperature was much less than that observed for low Ni steel alloys.
Are Assessment Data Really Driving Middle School Reading Instruction? What We Can Learn From One Student's Experience
Authors: Dennis Danielle V.
Published: March 2008

More and more, data from standardized assessments are being used to make instructional decisions for struggling middle school readers. Administrators must stop spending money on “silver‐bullet” curriculum programs and start spending money on training opportunities that will lead to autonomy and creativity in the classroom. In this article, the author demonstrates how one such program in a school district was inappropriate for one struggling reader and possibly many more.
Weblogs and Literary Response: Socially Situated Identities and Hybrid Social Languages in English Class Blogs
Authors: West Kathleen C.
Published: March 2008

Students engaged in literary response on weblogs they wrote and maintained for an 11th‐grade English class. Three focal students, all members of a “regular” American Literature class in a school that is highly invested in The College Board's Advanced Placement program, forge hybrid social languages from the discourse of formal literary analysis and the discourse of digital writing. In doing so, they position themselves as “serious literature students” by employing tools of literary analysis modeled and expected by English teachers at this school, and as “web‐literate communicators” by playing with language in ways that would not ordinarily be sanctioned as appropriate in English classes. In addition, each student borrows from other intertextual social languages to read class texts in new and unsanctioned ways, sometimes consciously and unconsciously pushing against dominant school culture.
When I Give, I Own: Building Literacy Through READ Community Libraries in Nepal
Authors: Neuman Susan B. , Khan Nafizuddin , Dondolo Thamsanqa
Published: March 2008

Under the auspices of the International Reading Association, an evaluation was conducted of Rural Education and Development (READ) program of creating community libraries in Nepal. READ set out to address the high rates of illiteracy and poverty in Nepal through the development of these libraries. To examine READ's approach, a team of international researchers conducted an evaluation to determine the efficacy of READ's participatory approach on literacy development and empowerment. Based on evidence from field notes, interviews, focus groups, and videotapes evaluators found strong support for the benefits of community libraries in providing access to literacy and improving economic and social development for the Nepalese citizens. READ libraries are promoting a “book culture” in Nepal by helping communities build upon their assets. Such an approach to libraries may effectively inform literacy efforts in the United States as well as in communities throughout the world.
A Simple Analytical Model for Predicting Gas Productivity of Horizontal Drain Holes with High-Friction
Authors: Guo Boyun , Ai Chi , Zhang Ling
Published: March 2008

It has been recognized that horizontal-wellbore friction significantly affects deliverability of gas wells in highly productive reservoirs. But there is lack of a simple and rigorous flow model for prediction and evaluation of such type of gas wells. This paper fills the gap.

Starting from the first law of thermodynamics and Darcy's law, the reservoir-horizontal wellbore cross-flow was modeled analytically in this study. Pressure and flow rate variations in the horizontal wellbore were formulated analytically. A simple closed-form equation for the total gas production rate from the well was derived. This newly developed mathematical model was compared with Joshi’s model and Furui’s model in a field-case study. The result shows that the error of the new model is 11.04%, which is much accurate than the other two models. Sensitivity analyses indicated that use of the new model is more beneficial in situations of high-permeability reservoirs, long horizontal wellbores, and small flow paths in the horizontal sections. This paper provides reservoir engineers an accurate and easy-to-use tool for prediction and evaluation of horizontal gas wells.
Cement Bond Evaluation
Authors: Shook Eddie H. , Frisch Gary J. , Lewis Tony
Published: March 2008

Because of increasing rig rates, the costs associated with the cement bond evaluation are now subject to scrutiny. Traditionally, the cost of the service and interpretation were linked to the value of the information provided, i.e. the quality of data gathered was directly related to the necessity of zonal isolation. The daily rig cost must now be considered, specifically costs directly related to the operating time required to acquire the cement evaluation data. The cost of operating rig time is often an order of magnitude higher than that of the cement bond logging service and should be a critical factor in the determination of the service provider and type of equipment run.

The correct logging tool and evaluation method provides the best process for evaluating the cement sheath. Several wellbore factors should be considered when selecting the proper tool for optimal results, including casing size, well deviation, fluid type, and fluid weight during the logging operations. However, the reservoir and the chosen completion should also influence the selection of the cement evaluation tool. Reservoir properties to consider include water contacts in or near zone of interest, drive mechanisms and isolation between production zones. The completion design, including perforation strategies, stimulation method, and sand control, should also influence the cement sheath evaluation process.

The challenges of a cost efficient and complete cement sheath evaluation required the development of a new cement evaluation tool. The FASTCAST™ tool expands the capabilities of CAST-V™ and existing analysis software. The new ultrasonic tools increase the logging speed up to five times, significantly reducing logging time, rig time, and costs. The tool provides cement evaluation and casing evaluation during the same logging pass. The existing software packages for cement and casing evaluation were updated to provide a complete analysis package for the new tool. The paper presents case histories to provide details about the economic advantage from using this new technology and processed logs showing both casing and cement evaluation.
Enhanced Net-to-Gross Understanding for Horizontal-Development Drilling in Complex Mature Reservoirs
Authors: Thorsen Arve K. , Eiane Tor , Thern Holger , Kroken Asbjørn , Iversen Marianne , Antonsen Frank
Published: March 2008

Determining net-to-gross in complex, mature reservoirs can prove challenging. Mixed lithologies, changes in sand quality and variations in oil-water contacts can, and do, cause uncertainties in the interpretation of conventional LWD measurements. This paper demonstrates how vibration tolerant LWD Magnetic Resonance (MR) measurements were used in the Troll field to address these conventional uncertainties.

Reservoir sands from several wellpaths were characterized using MR data for fluid identification, saturation determination and facies recognition. Fluid saturations are compared to those derived from traditional LWD formation evaluation measurements. Other petrophysical parameters such as porosity and permeability index are also evaluated. Finally, it is shown how the MR-LWD data can be integrated with imaging while drilling data to enhance structural interpretation in horizontal wells, for a new understanding of reservoir rock quality, moveable fluids and the resultant net-to-gross assessment.

The MR-data has proven to add valuable information to StatoilHydro in the understanding of the complex reservoir in its first field application in the North Sea. It was possible to gather high quality MR data in a highly challenging drilling environment

This paper will explore the ability to measure and utilize LWD-MR data to better understand the development of the reservoir of a mature field. The benefit is improved recovery and a better drainage strategy in a complex reservoir.
Future Projection of Energy Prices: A Predictive Model
Authors: Belhaj Hadi A. , Lay T.
Published: March 2008

As developing countries industrialize and rich countries continue to devour power, global energy demand is projected to increase 60% in the next 25-30 years, according to the International Energy Agency (IEA). Fossil fuels will continue to dominate, estimated to account for 85% of future demand. Even if the Saudi Kingdom pumps to full capacity, currently rated at 15 million barrels per day, it is anticipated that oil markets will face continuing high demand, which is to say that the Excess Demand for Oil (EDO) characterizing world oil markets since 1973, will continue to grow. Assuming current rates of consumption, U.S. reserves are forecast to last only another nine years, as domestic production in the U.S. continues a decades-long decline.

This paper, which forms part of a comprehensive study to develop economic models based on futuristic energy pricing policies, increasing globalization and better understanding of environmental impacts, analyzes oil prices over the last two decades as a basis for discussing four principal scenarios for predicting a general oil-price trend for the coming two decades. Concluding that a major supply-alleviating breakthrough from some other non-fossil-fuel alternative is unlikely, it therefore rules out the "Optimistic Model" scenario of a long-term steady-state for oil prices. After carefully considering the exploration efforts to increase the international reserves through new discoveries on the one hand, and the different implemented techniques of improved oil recovery (IOR) for maximizing production from discovered reservoirs on the other, it concludes instead that any of the other three models (two of them categorized as "Realistic") could emerge sometime in the next 3-5 years as the trend-setter.