bluuebunny/crossref_metadata_2025 huggingface dataset:
American Society of Diagnostic and Interventional Nephrology: Modification of the Peritoneoscopic Technique of Peritoneal Dialysis Catheter Insertion: Experience of an Interventional Nephrology Program
Authors: Asif Arif , Tawakol Jan , Khan Tasnim , Vieira Cristovao F. , Byers Patricia , Gadalean Florin , Hogan Rene , Merrill Donna , Roth David
Published: March 2004

Bowel perforation is a well‐recognized complication of peritoneal dialysis catheter insertion and is associated with increased morbidity and cost of medical care. In this article we describe our 2‐year experience (August 2001–October 2003) with a modified peritoneoscopic technique of peritoneal dialysis catheter insertion to minimize the incidence of bowel perforation. Seventy patients underwent 82 consecutive peritoneal dialysis catheter insertions using the innovative technique. The modified technique is very similar to the traditional peritoneoscopic procedure except for the following differences. To gain access to the peritoneal cavity, a Veress insufflation needle (Ethicon Endo‐Surgery Inc., Cincinnati, OH) is utilized instead of the trocar. In contrast to the sharp tip of the trocar, the Veress needle has a blunt, self‐retracting end. In addition, the Veress needle is only 14 gauge as opposed to the 2.2 mm diameter of the trocar. Upon introduction of the Veress needle into the abdominal cavity, two “pops” are discerned similar to the trocar. After introduction, 400–500 cc of air are infused and the needle is removed. The infusion of air creates a space between the peritoneal surface of the anterior abdominal wall and the bowel loops. At this point, the cannula with trocar is inserted into the space created. The rest of the steps of the procedure are the same as the traditional peritoneoscopic technique. Utilizing the innovative technique, all 82 catheter insertions were performed successfully without a single bowel perforation. No other complications except for catheter migration (n = 2) were noted. The extra cost of the needle ($35) should be viewed in the context of the costs associated with management of a bowel perforation. Large‐scale studies are needed to confirm the superiority of this innovative technique over the traditional peritoneoscopic insertion found in our case series. In the interim, however, the increased morbidity and cost associated with bowel perforation calls for logical measures to be taken to avoid this dreaded complication.
How We Detect Logical Inconsistencies
Authors: Johnson-Laird P.N. , Legrenzi Paolo , Girotto Vittorio
Published: March 2004

How do individuals detect inconsistencies? According to the theory described in this article, they search for a possibility represented in a mental model, in which each proposition in a description is true. If they find such a possibility, the description is consistent; otherwise, it is inconsistent. Evidence corroborates the theory. The evaluation of consistency is easy when the first possibility generated from the start of a description fits later propositions in the description; it is harder when this possibility does not fit later propositions, and individuals have to look for an alternative possibility. The theory postulates that models represent what is true, not what is false. As a result, individuals succumb to systematic illusions of consistency and of inconsistency.
Integration of Emotion and Cognitive Control
Authors: Gray Jeremy R.
Published: March 2004

Emotion is easily typecast as the nemesis of self-control. However, recent advances suggest a more nuanced view in which emotion and cognitive control are integrated, at times working in harmony. Emotional states can enhance high-level cognition, and can modulate the neural mechanisms that support cognitive control. Such an integrated neural organization might be adaptive: Emotional states could help resolve control dilemmas, facilitating the transition of the whole system into a more unified, situationally appropriate control state. This perspective is intriguing because control dilemmas are pervasive in human affairs (e.g., balancing risk vs. reward, short-term vs. long-term effects, and personal advantage vs. group advantage). Although many challenging questions remain, understanding emotion-cognition interactions at multiple levels of analysis is a realistic and exciting scientific goal.
Electrical Signals of Memory and of the Awareness of Remembering
Authors: Paller Ken A.
Published: March 2004

Learning factual information and accurately remembering specific experiences from the past are central to human intellectual and social life. These extraordinary abilities require computations on diverse sorts of information represented in the brain. Networks of neurons in the cerebral cortex are specialized for analyzing and representing such information, whereas the storage of facts and events within these networks depends fundamentally on linking multiple representational fragments together. This cross-cortical linking function is disrupted in patients with amnesia. Electrical measures of the brain in action, obtained while people perform feats of memory in laboratory settings, have been used to investigate the storage and retrieval of facts and episodes. Electrical signals associated with specific aspects of memory processing have been identified through research that constitutes part of a larger scientific endeavor aimed at understanding memory, the subjective experience of remembering that can accompany retrieval, and disorders of memory that can result from brain damage.
How People Make Decisions That Involve Risk
Authors: Reyna Valerie F.
Published: March 2004

Many health and safety problems, including war and terrorism, are by-products of how people reason about risk. I describe a new approach to reasoning about risk that implements a modern dual-process model of memory called fuzzy-trace theory. This approach posits encoding of both verbatim and gist representations, with reliance on the latter whenever possible; dependence of reasoning on retrieval cues that access stored values and principles; and vulnerability of reasoning to processing interference from overlapping classes of events, which causes denominator neglect in risk or probability judgments. These simple principles explain classic and new findings, for example, the finding that people overestimate small risks but ignore very small risks. Fuzzy-trace theory differs from other dual-process approaches to reasoning in that it places intuition at the apex of development, considering fuzzy intuitive processing more advanced than precise computational processing (e.g., trading off risks and rewards). The theory supplies a conception of rationality that distinguishes degrees of severity of errors in reasoning. It also includes a mechanism for achieving consistency in reasoning, a hallmark of rationality, by explaining how a person can treat superficially different reasoning problems in the same way if the problems share an underlying gist.
Children's Search for Gender Cues
Authors: Martin Carol Lynn , Ruble Diane
Published: March 2004

Young children search for cues about gender—who should or should not do a particular activity, who can play with whom, and why girls and boys are different. From a vast array of gendered cues in their social worlds, children quickly form an impressive constellation of gender cognitions, including gender self-conceptions (gender identity) and gender stereotypes. Cognitive perspectives on gender development (i.e., cognitive developmental theory and gender-schema theory) assume that children actively search for ways to make sense of the social world that surrounds them. Gender identity develops as children realize that they belong to one gender group, and the consequences include increased motivation to be similar to other members of their group, preferences for members of their own group, selective attention to and memory for information relevant to their own sex, and increased interest in activities relevant to their own sex. Cognitive perspectives have been influential in increasing understanding of how children develop and apply gender stereotypes, and in their focus on children's active role in gender socialization.
The Role of Prenatal Maternal Stress in Child Development
Authors: DiPietro Janet A.
Published: March 2004

The notion that a woman's psychological state during pregnancy affects the fetus is a persistent cultural belief in many parts of the world. Recent results indicate that prenatal maternal distress in rodents and nonhuman primates negatively influences long-term learning, motor development, and behavior in their offspring. The applicability of these findings to human pregnancy and child development is considered in this article. Potential mechanisms through which maternal psychological functioning may alter development of the fetal nervous system are being identified by current research, but it is premature to conclude that maternal prenatal stress has negative consequences for child development. Mild stress may be a necessary condition for optimal development.
The Benefit of Additional Opinions
Authors: Yaniv Ilan
Published: March 2004

In daily decision making, people often solicit one another's opinions in the hope of improving their own judgment. According to both theory and empirical results, integrating even a few opinions is beneficial, with the accuracy gains diminishing as the bias of the judges or the correlation between their opinions increases. Decision makers using intuitive policies for integrating others' opinions rely on a variety of accuracy cues in weighting the opinions they receive. They tend to discount dissenters and to give greater weight to their own opinion than to other people's opinions.
Induction of apoptosis in monocytes and lymphocytes by serum from patients with systemic lupus erythematosus − an additional mechanism to increased autoantigen load?
Authors: BENGTSSON A A , STURFELT G , GULLSTRAND B , TRUEDSSON L
Published: March 2004

The most likely source of autoantigens in systemic lupus erythematosus (SLE) is apoptotic material. Because increased levels of circulating apoptotic cells are found in SLE we wanted to investigate the capacity of serum from patients with SLE or other autoimmune or infectious diseases and normal healthy donors (NHD) to induce apoptosis in normal monocytes, lymphocytes and corresponding cell lines, in relation to clinical and immunological data. Monocytes and lymphocytes from healthy donors were incubated with sera from 37 SLE patients, 37 sex- and age-matched NHD and sera from patients with rheumatoid arthritis, vasculitis, sepsis and mononucleosis. Sera from SLE patients were sampled at both active and inactive disease. The apoptosis-inducing effect (AIE) of these sera was monitored with flow cytometry using annexin V and propidium iodide (PI) binding. The AIE in monocytes and lymphocytes was significantly higher in sera from SLE patients than in other patient groups and NHD (P < 0·001) and was also higher when cell lines were used. Level of C5a in cell culture supernatant correlated with AIE in monocytes (r = 0·451, P = 0·005), suggesting involvement of complement. Heat-inactivation of sera did not affect the AIE, nor did depletion of IgG by protein G absorption of serum. Kinetic analyses showed a peak in apoptosis induction at 12–16 h, with a delayed PI positivity. AIE was equally high using sera from active and inactive SLE cases, and did not correlate with the SLE Disease Activity Index (SLEDAI). Thus, SLE serum has a strong and apparently disease-specific apoptosis-inducing capacity, which could contribute to a high load of potential autoantigen.
Politics and Power in the European Convention
Authors: Crum Ben
Published: March 2004

The Convention on the future of the European Union has been heralded by many as a unique political setting. So far the process of EU Treaty change was subject to the collision of national political interests in Intergovernmental Conferences. By contrast, the Convention appears to promise a fundamentally open and normatively informed arena. This article probes the validity of this promise by dissecting the political dynamics of the Convention along three dimensions: political behaviour and alliance formation; agenda management; and the norms informing its proceedings.
Developing Conceptualisations of Europeanisation: A Study of Financial Services
Authors: Howell Kerry E.
Published: March 2004

In its most explicit form Europeanisation is conceptualised as the process of downloading European Union (EU) directives, regulations and institutional structures to the domestic level. However, this conceptualisation of Europeanisation has been extended in the literature in terms of up-loading to the EU shared beliefs, informal and formal rules, discourse, identities and vertical and horizontal policy transfer. This article undertakes a study of banking, investment and insurance directives to analyse the impact of Europeanisation on the UK financial services sector.
The Impact of Devolution on Women's Political Representation Levels in Northern Ireland
Authors: Donaghy Tahnya Barnett
Published: March 2004

Historically, Northern Ireland women have been severely under-represented in the formal political arena. Despite the main parties having failed to address this issue, women have notably increased their presence in elected positions since the establishment of the Northern Ireland Assembly in 1998. In the absence of any initiatives undertaken specifically to improve women's political status, it appears that the opportunities of devolution have facilitated these recent achievements. Specifically, the new political landscape has become more open and conducive to promoting women into positions of political power, and it is the impact of these developments that this article explores.
The Continued Relevance of Local Parties in Representative Democracies
Authors: Clark Alistair
Published: March 2004

This article assesses the value of local parties. It asks why political parties value their local sections. It also considers the ways in which local parties can benefit society. Local parties act as a democratic training ground for party members, are a conduit for political communication and provide parties with a range of resources. They also act as problem solving agencies; they ensure that policy is responsive to local needs; they provide an additional channel of communication and accountability; and they link citizens with the state. The article ends with an appeal to party scholars to refocus their attention towards local parties.
The Politics of ‘Cyberconflict’
Authors: Karatzogianni Athina
Published: March 2004

The turn of the century witnessed the emergence of a new kind of conflict named ‘cyberconflict’, meaning conflict in computer-mediated environments (cyberspace). This article seeks to introduce the key terms and themes of cyberconflict and argue that two different trends occur: one between ethnic or religious groups fighting in cyberspace, as they do in real life; and second, between a social movement and its antagonistic institution (hacktivism).
Corporate Social Responsibility: A New Signifier? An Analysis of Business Ethics and Good Business Practice
Authors: Manokha Ivan
Published: March 2004

The subject of this article is the increasing commitment declared by business enterprises to ethical business practices and corporate social responsibility. It is approached using Jean Baudrillard's analysis of the way ‘signifiers’ are attached to products in advanced capitalist society. In such societies signifiers are split off from signifieds and their referents (commodities). The main linguistic form is not the symbol, as in previous social settings, but the signal. Since the linguistic elements are fragmented, signifiers are able to ‘float’ in the social space and be combined with the signifieds and referents at will. Thus, the producers often emphasise not the use value of the commodities in their advertisement but instead randomly attach various qualities to commodities irrespective of their functionality or material utility. In this article the development of corporate social responsibility is seen as such a signifier and the implications thereof for the late-modern Global Political Economy are discussed.
Nietzsche, Historiography and Yugoslav Nationalism
Authors: Jacoby Tim
Published: March 2004

In The Use and Abuse of History Friedrich Nietzsche warned of the dangers of separating history from the irrationality of nature and establishing it as a science. Increasingly individualised, spiritually adrift and soulless, Man, he suggests, will become a prisoner of an excess of history imposed upon, and external to, life itself. This article will argue that contained within Nietzsche's polemic, particularly his elaboration of an alternative effective methodology, is a useful framework for the analysis of historiography's construction of the past. The development of nationalist mythologies within the politics of the former Yugoslavia is then discussed in light of this interpretation of Nietzsche's position.
Cornel West and the Tempest in the Ivory Tower
Authors: Cowan Rosemary
Published: March 2004

A major American news story of 2002 centred on a dispute at Harvard between president Lawrence Summers and Cornel West. This article explores why many commentators erroneously portrayed the dispute between the two men as a matter of civil rights and affirmative action. It also examines the issue at the heart of the fracas, namely a long-running debate about the quality of West's scholarship, and considers whether his commitments to publics outside the classroom detract from his scholarly work. Is the release of a hip-hop CD an appropriate form of intellectual activity for a senior Ivy League professor?
Longitudinal Changes of Solute Transport in Peritonitis‐free Peritoneal Dialysis Patients
Authors: Hung Shih‐Yuan , Hung Yao‐Min , Chiou Yee‐Hsuan , Chou Kang‐Ju , Chung Hsiao‐Min
Published: March 2004

Abstract:  Background:  The aim of this study was to evaluate the longitudinal changes in peritoneal transport in patients on long‐term, peritonitis‐free, continuous ambulatory peritoneal dialysis (CAPD) therapy.

Methods:  Results were longitudinally recorded for the standard peritoneal equilibration test (PET) in 76 consecutive, nondiabetic, adult patients from the beginning of CAPD therapy until their first episodes of peritonitis, abdominal surgery, or any cause of drop out. The PET results were evaluated once annually using the dialysate‐to‐plasma  ratio  of  creati‐nine (D/PCr) and the dialysate‐to‐instilled dextrose ratio (D4/D0) at 4 hours after beginning dialysis.

Results:  A total of 168 PET results were obtained. A statistically significant tendency toward decreased D/PCr and increased D4/D0 values over time for up to 3 years was found.

Conclusions:  This  study  shows  a  tendency  toward  progressive  decline in small molecular transport over time in nondiabetic patients with uneventful CAPD therapy. Sequential PET follow‐up cannot be overlooked in peritonitis‐free CAPD patients.
Preclinical Assessment of a Transaortic Venting Catheter for Percutaneous Cardiopulmonary Support
Authors: Kitamura Masaya , Hanzawa Kazuhiko , Takekubo Masaru , Aoki Kenji , Hayashi Jun‐ichi
Published: March 2004

Abstract:  Left ventricular unloading and energy charge as effects of transaortic catheter venting (TACV) during venoarterial bypass (VAB) in normal and failing hearts has been reported previously. The aim of this study was to assess the effectiveness and safety of a special multipurpose catheter for TACV during percutaneous cardiopulmonary support (PCPS) in a preclinical setting. Six adult pigs underwent PCPS with or without the TACV. With standard hemodynamic monitoring, LV volume and function were assessed by direct ultrasonic cardiography (UCG) in each condition. PCPS was smoothly established and the TACV catheter was safely introduced in all cases. As compared with isolated PCPS, the TACV combined with PCPS maintained significant blood flow with LV venting and systemic perfusion: the heart rate of the native heart, systemic arterial pressure, and central venous pressure were stable. Also the additional TACV led to a significant reduction of LV preload during PCPS, and the reduction was 25–30% of LVDd and 20–35% of LVAd. The results of this investigation suggest that clinical application of the TACV technique with a clinical PCPS circuit would be feasible and additional TACV might be use‐ful for LV recovery during PCPS in patients with severe heart failure.
Serum Growth Factors in Hemodialyzed Patients
Authors: Pa̧czek Leszek , Gomółka Małgorzata , Niemczyk Stanisław , Bartłomiejczyk Irena , Gerwatowska Dorota , Sebekova Katerina , Heidland August
Published: March 2004

Abstract:  The contact of chronic hemodialysis patients’ blood with components of extracorporeal circulation leads to mobilization of several systemic reactions. The purpose of this study was to determine the activity of transforming growth factor (TGF‐β1) and platelet derived growth factor (PDGF) in serum of patients on long‐term hemodialysis program and to compare these results with ones obtained in healthy volunteers. Twenty‐five patients on dialysis carried out on polysulfone membrane dialyzer, and 16 patients on dialysis with the used of cuprophan membrane dialyzer on long‐term hemodialysis program participated in the study. TGF‐β1 level in serum of healthy volunteers (12.06 ± 7.56 ng/mL) was lower than in serum of patients dialyzed on polysulfone membrane  dialyzers  (26.56 ± 14.83 ng/mL).  Differences  in PDGF concentrations in serum of control group and hemodialyzed patients were not statistically significant. The strong correlation between TGF‐β1 and PDGF in serum of both studied groups of patients was dem‐onstrated.
Hepatitis C Virus Decreases in Patients with Maintenance Hemofiltration Therapy
Authors: Ishida Hideki , Tanabe Kazunari , Tokumoto Tadahiko , Shimizu Tomokazu , Shimmura Hiroaki , Yoshioka Takashi , Toma Hiroshi
Published: March 2004

Abstract:  Low incidence rates of hepatocellular carcinoma and cirrhosis in HCV‐antibody‐positive patients on chronic hemodialysis are reported. Among the patients, two cases undergoing negative conversion of the anti‐HCV‐antibody were found. Considering the size of the virus particles and the pore size of the dialysis membrane, it seems the virus does not escape from the membrane pore. Indeed, virus particles may be trapped and destroyed at the membrane surface. The size of HCV‐RNA titers in HCV‐antibody‐positive patients receiving various kinds of chronic blood purification procedures are of interest. The subjects included 15 hemodialysis patients, 10 hemofiltration patients, 9 continuous ambulatory peritoneal dialysis patients, 7 chronic renal failure predialysis patients, and 14 patients with excellent renal function. The concentration of HCV‐RNA particles in patients receiving chronic hemofiltration was significantly lower than that in patients of other groups. Hemofiltration, which is routinely performed at over 150 mm Hg TMP, may be an important key to decreasing HCV‐RNA particles by a mechanism such as destruction.
Impeller Behavior and Displacement of the VentrAssist Implantable Rotary Blood Pump
Authors: Chung Michael K.H. , Zhang Nong , Tansley Geoff D. , Woodard John C.
Published: March 2004

Abstract:  The VentrAssist implantable rotary blood pump, intended for long‐term ventricular assist, is under development and is currently being tested for its rotor‐dynamic stability. The pump is of the centrifugal type and consists of a shaftless impeller, also acting as the rotor of the brushless DC motor. The impeller remains passively suspended in the pump cavity by hydrodynamic forces, resulting from the small clearances between the impeller outside surfaces and the pump cavity. In the older version of the pump tested, these small clearances range from approximately 50 µm to 230 µm; the displacement of the impeller relative to the pump cavity is unknown in use. This article presents two experiments: the first measured displacement of the impeller using eddy‐current proximity sensors and laser proximity sensors. The second experiment used Hall‐effect proximity sensors to measure the displacement of the impeller relative to the pump cavity. All transducers were calibrated prior to commencement of the experiments. Voltage output from the transducers was converted into impeller movement in five degrees of freedom (x, y, z, θx, and θy). The sixth degree of freedom, the rotation about the impeller axis (θz), was determined by the commutation performed by the motor controller. The impeller displacement was found to be within the acceptable range of 8 µm to 222 µm, avoiding blood damage and contact between the impeller and cavity walls. Thus the impeller was hydrodynamically suspended within the pump cavity and results were typical of centrifugal pump behavior. This research will be the basis for further investigation into the stiffness and damping coefficient of the pump's hydrodynamic bearing.
Optimal Continuous Retrograde Coronary Perfusion Flow Rate with Beating Heart in Normal Temperature
Authors: Tsukioka Toshihide , Tomita Sigeyuki , Watanabe Go , Takemura Hirohumi
Published: March 2004

Abstract:  Purpose:  We were led to the premise that with retrograde oxygenated blood perfusion, it would be possible to perform operations on the beating heart.

Methods:  The experiment consisted of two stages: procedure 1 and 2. In procedure 1, six pigs were used. Retrograde perfusion flow was controlled to be in the range of 5.0–10.0 mL/kg/min and was gradually increased. In procedure 2, six pigs were used. Retrograde perfusion was continued for 120 min at the optimal flow rate obtained from procedure 1.

Results:  The optimal flow rate was 7.0 mL/kg/min in procedure 1. In procedure 2, retrograde perfusions for 120 min were performed with perfusion flows set at optimal flow rate.

Conclusions:  The procedure used in this study made it possible to maintain empty beating heart with normal sinus rhythm for 120 min, and the results suggest the possibility of clinical application to open heart surgery.
Correlation Studies of Plasma Paraoxonase Activity and Uric Acid Concentration with AAPH‐Induced Erythrocyte Hemolysis in Hemodialysis Patients
Authors: Kirschbaum Barry
Published: March 2004

Abstract:  Uric acid possesses antioxidant properties and is an important determinant of total plasma antioxidant capacity. Uric acid concentrations tend to be elevated in patients with renal failure requiring maintenance hemodialysis but are abruptly reduced by the dialysis procedure itself. Paraoxonase (PON1), an enzyme which circulates in association with high density lipoprotein (HDL), confers protection  against  free  radicals  by limiting  the  oxidation of phospholipids. The relationship between pre‐ and postdialysis uric acid concentration, PON1 activity, and high density lipoprotein cholesterol (HDL‐C) level and the resistance of erythrocytes from hemodialysis patients to hemolysis induced by the free radical generator 2,2′‐azobis(2‐amidinopropane) dihydrochloride (AAPH) was studied. Red cells were washed free of plasma prior to the assay, and no plasma was added to the hemolysis assay tubes. Postdialysis erythrocytes were found to be more susceptible to hemolysis compared to blood samples obtained at the initiation of the session (784 ± 713 vs. 256 ± 256 µmol/L hemoglobin released after 60 min incubation and 1530 ± 696 vs. 1354 ± 757 µmol/L at 90 min). Hemolysis correlated negatively with the concentration of uric acid and positively with PON1 arylesterase activity but not with HDL‐C level in the corresponding plasma samples. There was a strong negative correlation between uric acid and PON1 in predialysis blood samples (r 2 = 0.4, P < 0.001). The conclusion is that the reciprocal relationship between uric acid and PON1 may reflect a mechanism that protects erythrocytes from subsequent oxidative stress.
Lentivirus‐based Gene Delivery in Mouse Embryonic Stem Cells
Authors: Kosaka Yoshikazu , Kobayashi Naoya , Fukazawa Takuya , Totsugawa Toshinori , Maruyama Masanobu , Yong Chen , Arata Takashi , Ikeda Hideaki , Kobayashi Kazuya , Ueda Tadayoshi , Kurabayashi Yuzuru , Tanaka Noriaki
Published: March 2004

Abstract:  Background:  Embryonic stem (ES) cells are widely used in therapeutic research as an unlimited source of cell therapy. Therefore, it is of great value to find a way to efficiently manipulate ES cells. HIV‐1‐derived lentiviral vectors are now considered to be an efficient vehicle for delivering genes into a variety of cells. In this study, we examined the efficacy of lentivirus‐based gene delivery into mouse ES (mES) cells.

Materials and methods:  Recombinant HIV‐I‐based lentiviral vectors Lt‐GFP, expressing green fluorescent protein (GFP), and Lt‐LacZ, expressing E. coli LacZ gene in conjunction with neomycin resistance gene, were generated using a FuGENE 6 transduction method and used for transducing ES cells derived from 129Sv mice. Lentiviral transduction efficacy was evaluated by GFP expression assay using flow cytometry and by X‐gal staining. The in vivo potential of developing teratoma of such transduced mES cells was examined in severe combined immunodeficiency (SCID) mice.

Results:  FuGENE 6 showed no considerable transduction‐associated cytotoxicity. The expression rate of GFP and LacZ of mES cells increased on a multiplicity of infection (MOI)‐dependent manner with the amount of Lt‐GFP and Lt‐LacZ used. Approximately 42% of mES cells were positive for GFP after infection of Lt‐GFP at an MOI of 30. Notably, after G418 selection, nearly 100% of Lt‐LacZ‐transduced mES cells were positive for LacZ and formed teratomas in SCID mice.

Conclusions:  This work demonstrates that HIV‐I‐based lentiviral vectors are capable of transducing mES cells. Lentiviral vectors may facilitate an advance in the field of gene transfer and expression in various types of ES cells, including human  ES  cells.
Artificial Cells for Cell and Organ Replacements
Authors: Chang Thomas Ming Swi
Published: March 2004

Abstract:  The artificial cell is a Canadian invention (Chang, Science, 1964). This principle is being actively investigated for use in cell and organ replacements. The earliest routine clinical use of artificial cells is in the form of coated activated charcoal for hemoperfusion for use in the removal of drugs, and toxins and waste in uremia and liver failure. Encapsulated cells are being studied for the treatment of diabetes, liver failure, and kidney failure, and the use of encapsulated genetically‐engineered cells is being investigated for gene therapy. Blood substitutes based on modified hemoglobin are already in Phase III clinical trials in patients, with as much as 20 units being infused into each patient during trauma surgery. Artificial cells containing enzymes are being developed for clinical trial in hereditary enzyme deficiency diseases and other diseases. The artificial cell is also being investigated for drug  delivery and for other uses in biotechnology, chemical engineering, and medicine.
Under‐Utilization of Mechanical Circulatory Support in Canada: Why and What Can Be Done?
Authors: Mussivand Tofy , Carrier Michel , Chiu Ray C.J. , Davies Ross A. , Delgado Diego H. , Deng Mario C. , Haddad Haissam , Hendry Paul J. , Keon Wilbert J. , Koshal Arvind , Masters Roy G. , Mesana Thierry , Rao Vivek
Published: March 2004

Abstract:  In October of 2002, a workshop was held as part of the Canadian Cardiovascular Congress in Edmonton, Canada, entitled “Under‐Utilization of Mechanical Circulatory Support in Canada. Why and What Can Be Done?” The workshop examined various issues related to the use of mechanical circulatory support devices in the Canadian context. Representatives from all Canadian centers with active mechanical circulatory support programs were invited to participate and participants included surgeons and cardiologists, as well as other affiliated health professionals. Opinions were solicited from the workshop participants and a series of recommendations were formulated.
Hla-Dq Typing in The Diagnosis of Celiac Disease
Authors: Kaukinen Katri , Partanen Jukka , Mäki Markku , Collin Pekka
Published: March 2004

ABSTRACT

OBJECTIVE:

More than 95% of celiac patients share the major histocompatibility complex II class human leukocyte antigen (HLA) DQ2 or DQ8 haplotype; patients negative for both types are unlikely to suffer from celiac disease. Our aim was to investigate whether HLA-DQ2 and -DQ8 typing is helpful when diagnosis is uncertain because of the absence of unequivocal small bowel villous atrophy.

METHODS:

HLA-DQ2 and -DQ8 typing was carried out in 59 patients evincing nondiagnostic small bowel mucosal lesion or positive celiac serology, and in 17 patients maintaining a gluten-free diet without biopsy-proven celiac disease. HLA findings were compared to small bowel mucosal morphology; intraepithelial lymphocytes; and serum endomysial (EmA), reticulin, tissue transglutaminase (anti-tTG) and gliadin antibodies.

RESULTS:

Of the 59 patients evincing only minor small bowel mucosal changes or positive celiac disease serology, 22 (37%) were negative for DQ2 and DQ8. All EmA-positive patients had celiac-type HLA, but antireticulin antibody, anti-tTg, and antigliadin antibody were also present in HLA-DQ2– and -DQ8–negative individuals. Eleven of 17 patients (65%) observing a gluten-free diet before small bowel biopsy did not share celiac-type HLA. None of the 17 had apparent villous atrophy. Serum EmA and anti-tTG were negative in all. HLA-DQ typing is less expensive than follow-up biopsy in the exclusion of celiac disease.

CONCLUSIONS:

HLA-DQ2 and -DQ8 determination is useful in exclusion, probably lifelong, of celiac disease in individuals with an equivocal small bowel histological finding. The low specificity of this test must, however, be borne in mind.
Portal Vein Thrombosis: A Concise Review
Authors: Sobhonslidsuk Abhasnee , Reddy Rajender K
Published: March 2004

ABSTRACT

Portal vein thrombosis (PVT) is an uncommon cause for presinusoidal portal hypertension. Although several predisposing conditions are known to exist in the background of PVT, there still remains a proportion of patients in whom the etiology is not known and the pathogenesis is unclear. In this review we summarize the literature on PVT and present the current knowledge about the precipitating factors of PVT. Further, we discuss the advances in the radiological diagnosis that have improved diagnostic accuracy and are noninvasive. Finally, we discuss the treatment options for patients who have varying extents of thrombosis in the portal vein and specifically focus on PVT that is encountered before and after liver transplantation.
Nsaid Inhibition of Gi Cancer Growth: Clinical Implications and Molecular Mechanisms of Action
Authors: Husain Syeda S , Szabo Imre L , Tarnawski Andrzej S
Published: March 2004

ABSTRACT

Epidemiological studies suggest that aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs) reduce the incidence of and mortality from colorectal, gastric, and esophageal cancers. The precise mechanisms by which NSAIDs exert their chemopreventive effects are not fully explained, but likely involve inhibition of cyclo-oxygenase, the enzyme that converts arachidonic acid to prostaglandins. Two isoforms of this enzyme, cyclo-oxygenase 1 (COX-1) and COX-2, have been identified. COX-2 is absent in normal mucosa but is overexpressed in colonic, gastric, and esophageal cancers, as well as their precursor lesions. The inhibition of COX-2 through either pharmacological agents or gene deletion results in suppression of colonic polyp formation. NSAIDs reduce colonic, gastric, and esophageal cancer cell growth, in part, by inducing apoptosis. However, the antineoplastic effects of NSAIDs may be partly independent of their ability to inhibit COX-2. The mechanisms involved in the antineoplastic actions of NSAIDs include inhibition of angiogenesis (essential for delivery of oxygen and nutrients to a growing tumor), induction of apoptosis (which is usually reduced in cancer cells) by stimulation of proapoptotic genes, and direct inhibition of cancer cell growth by blocking signal transduction pathways responsible for cell proliferation.
Clinical, Endoscopic, and Functional Studies in 408 Patients With Barrett's Esophagus, Compared To 174 Cases of Intestinal Metaplasia of The Cardia
Authors: Csendes Attila , Smok Gladys , Quiroz Juan , Burdiles Patricio , Rojas Jorge , Castro César , Henríquez Ana
Published: March 2004

ABSTRACT

OBJECTIVE:

The pathophysiology of gastroesophageal reflux disease (GERD) has been studied extensively in patients with long-segment Barrett's esophagus (LSBE), but few reports have explored GERD pathophysiology in patients who have short-segment Barrett's esophagus (SSBE) or intestinal metaplasia at the cardia (IMC). We aimed to compare clinical, endoscopic, histological, and functional features in patients with LSBE, SSBE, and IMC.

METHODS:

We identified 582 patients who had intestinal metaplasia at the squamocolumnar junction in the distal esophagus and divided them into three groups based on the extent of columnar-lined esophagus observed endoscopically: 1) patients with IMC who had no columnar-lined esophagus (i.e., the squamocolumnar and gastroesophageal junctions coincided), 2) patients with LSBE who had >3 cm of columnar-lined esophagus, and 3) patients with SSBE who had <3 cm of columnar-lined esophagus. All patients had esophageal manometric evaluation, and 24-h esophageal pH monitoring was performed to determine the extent of acid and bile (bilirubin) reflux.

RESULTS:

There were 174 patients with IMC, 155 with LSBE, and 25 with SSBE. Compared to patients with LSBE and SSBE, patients with IMC had significantly lower frequencies of GERD symptoms, hiatal hernia, and erosive esophagitis; significantly higher lower esophageal sphincter pressures; and significantly shorter durations of acid and bile reflux. Between patients with SSBE and LSBE, significant differences were found in the frequency of hiatal hernia and duration of acid reflux (both greater in the patients with LSBE). Also, dysplasia was significantly more frequent in patients with LSBE than in those with SSBE or IMC.

CONCLUSION:

GERD symptoms, signs, and physiological abnormalities are found more often in patients with Barrett's esophagus than in those with IMC, and the duration of acid reflux in patients with LSBE is greater than that in patients with SSBE. These findings suggest that the extent of intestinal metaplasia in the esophagus is related directly to the severity of underlying GERD.
Esomeprazole (40 Mg) Compared With Lansoprazole (30 Mg) in The Treatment of Erosive Esophagitis
Authors: Castell Donald O , Kahrilas Peter J , Richter Joel E , Vakil Nimish B , Johnson David A , Zuckerman Seth , Skammer Wendy , Levine Jeffrey G
Published: March 2004

ABSTRACT

OBJECTIVES:

Esomeprazole, the S isomer of omeprazole, has been shown to have higher healing rates of erosive esophagitis than omeprazole. This study compared esomeprazole with lansoprazole for the healing of erosive esophagitis and resolution of heartburn.

METHODS:

This United States multicenter, randomized, double blind, parallel group trial was performed in 5241 adult patients (intent-to-treat population) with endoscopically documented erosive esophagitis, which was graded by severity at baseline (Los Angeles classification). Patients received 40 mg of esomeprazole (n = 2624) or 30 mg of lansoprazole (n = 2617) once daily before breakfast for up to 8 wk. The primary efficacy endpoint was healing of erosive esophagitis at week 8. Secondary assessments included proportion of patients healed at week 4, resolution of investigator-recorded heartburn, time to first and time to sustained resolution of patient diary-recorded heartburn, and proportion of heartburn-free days and nights.

RESULTS:

Esomeprazole (40 mg) demonstrated significantly higher healing rates (92.6%, 95% CI = 91.5–93.6%) than lansoprazole (30 mg) (88.8%, 95% CI = 87.5–90.0%) at week 8 (p = 0.0001, life-table estimates, intent-to-treat analysis). A significant difference in healing rates favoring esomeprazole was also observed at week 4. The difference in healing rates between esomeprazole and lansoprazole increased as baseline severity of erosive esophagitis increased. Sustained resolution of heartburn occurred faster and in more patients treated with esomeprazole. Sustained resolution of nocturnal heartburn also occurred faster with esomeprazole. Both treatments were well tolerated.

CONCLUSIONS:

Esomeprazole (40 mg) is more effective than lansoprazole (30 mg) in healing erosive esophagitis and resolving heartburn. Healing rates are consistently high with esomeprazole, irrespective of baseline disease severity.
Predictive Factors of Gi Lesions in 241 Women With Iron Deficiency Anemia
Authors: Nahon Stéphane , Lahmek Pierre , Lesgourgues Bruno , Nahon-Uzan Karine , Tuszynski Thierry , Traissac Laurent , Delas Nicolas
Published: March 2004

ABSTRACT

OBJECTIVES:

GI blood loss is the most common cause of iron deficiency anemia (IDA) in postmenopausal women and menstrual blood loss in premenopausal women. We aimed to evaluate the diagnostic yield of endoscopy in women with IDA and to define predictive factors of a GI lesion.

METHOD:

Clinical, biological, endoscopic, and histological data from patients with IDA were systematically collected on a computer. Multivariate analysis (logistic regression) was performed to determine whether these data were associated with a GI lesion.

RESULTS:

Between January, 1989 and June, 1999, 241 consecutive women had endoscopies for IDA (mean age = 52.3 ± 21.8 yr). A substantial GI lesion was detected in 119 patients (49.4%). Ten patients (4%) had both upper and lower GI lesions. A source of IDA was revealed by upper endoscopy in 86 cases (35.6%) and by colonoscopy in 33 (13.7%). The most common upper lesions were peptic ulceration (42/241 [17.4%]), esophagitis (15/241 [6.2%]), and cancer (9/241 [3.7%]). Colonic cancer (15/241 [6.2%]) and polyps (10/241 [4.1%]) were the most frequent lesions detected by colonoscopy. Predictive factors (odds ratio, 95% CI) of GI lesions diagnosed by endoscopy were abdominal symptoms (8.3, 3.9–17.2), age > 50 yr (4.4, 2.1–9.2), and Hb < 9 g/dl (3, 1.5–6.1). Thirty-one women (13%) had none of these predictive factors; in this group only two lesions were identified (one esophagitis and one duodenal ulcer). The positive predictive value of these three independent predictors was 87%, and the negative predictive value was 93.5%.

CONCLUSION:

Endoscopy revealed a source of IDA in 49.4% of cases. Three predictive factors of GI lesion were identified. Endoscopic investigation should be avoided in women without these three predictive factors. Conversely, these factors are strongly associated with a GI lesion.
Evaluation of The Helicobacter Pylori Stool Antigen Test for Monitoring Eradication Therapy
Authors: Odaka Takeo , Yamaguchi Taketo , Koyama Hidehiko , Saisho Hiromitsu , Nomura Fumio
Published: March 2004

ABSTRACT

OBJECTIVE:

We aimed to clarify the time course of the Helicobacter pylori stool antigen (HpSA) level during and after eradication therapy and to determine the appropriate time of measurement of HpSA to evaluate eradication.

METHODS:

The subjects were 47 patients who were positive for H. pylori. The patients underwent a 1-wk regimen of triple therapy. The outcome of the eradication therapy was judged by urea breath test, culture, and histology 6 wk after the end of treatment. The HpSA level was serially measured nine times from before therapy until 12 wk after the end of therapy.

RESULTS:

In the group with successful eradication, HpSA became negative immediately after the end of therapy and the negativity persisted. In contrast, in the noneradication group HpSA became negative immediately after therapy, but became positive again within 2 wk after the end of therapy. The mean absorbance value of the HpSA test on the 4th day after the initiation of eradication therapy was significantly higher in the noneradication group than in the group with successful eradication. The diagnostic accuracy of the HpSA test increased to ≧90% 2 wk after therapy and thereafter. Comparison of the diagnostic accuracy at 4 wk after the end of therapy showed no significant differences with that at 2, 6, 8, and 12 wk after the end of therapy.

CONCLUSIONS:

The course of the HpSA levels during and after eradication therapy in patients with successful eradication was quite different from that in noneradication patients. Measurement of HpSA was useful to evaluate eradication, and the appropriate evaluation of the outcome of treatment could be made as early as 2 wk after the end of therapy.
Gi Symptoms in Diabetes Mellitus Are Associated With Both Poor Glycemic Control and Diabetic Complications
Authors: Bytzer Peter , Talley Nicholas J , Hammer Johann , Young Lisa J , Jones Michael P , Horowitz Michael
Published: March 2004

ABSTRACT

OBJECTIVE:

Diabetes mellitus is associated with an increased prevalence of GI symptoms, but the mechanisms underlying symptoms are poorly defined and controversial. We aimed to determine whether there is a relationship between GI symptoms and both diabetic complications and glycemic control.

METHODS:

We performed a cross-sectional questionnaire study of 1101 subjects with diabetes mellitus recruited from outpatient clinics (n = 209) and the community (n = 892). Data on eight GI symptom groups, complications of diabetes (retinopathy, neuropathy, nephropathy), and self-reported glycemic control were obtained from a validated questionnaire. Glycated hemoglobin was measured in 463 of the subjects. The association between diabetic complications, glycemic control, and GI symptoms was assessed using logistic regression analysis, adjusted for demographic and clinical factors.

RESULTS:

Of the 1101 subjects, 57% reported at least one complication. Diabetic complications were independently associated with both symptom complexity (number of symptom groups reported) (adjusted odds ratio = 1.92 per symptom group [95% CI = 1.51–2.45]) and seven of the eight GI symptom groups. For all symptom groups, the association was explained by self-reported symptoms of peripheral neuropathy. Poor glycemic control measured by both self-report and Hb A1c was an independent risk factor for upper GI symptoms, whereas other potential risk indicators, including duration and type of diabetes, were not significant.

CONCLUSIONS:

GI symptoms in diabetes mellitus may be linked to diabetic complications, particularly peripheral neuropathy, and to poor glycemic control.