bluuebunny/crossref_metadata_2025 huggingface dataset:
Interleukin‐2 Gene Polymorphisms Associated with Increased Risk of Gastric Atrophy from Helicobacter pylori Infection
Authors: Togawa Shozo , Joh Takashi , Itoh Makoto , Katsuda Nobuyuki , Ito Hidemi , Matsuo Keitaro , Tajima Kazuo , Hamajima Nobuyuki
Published: May 2005

Background.  Gastric atrophy induced by Helicobacter pylori is thought to predispose patients to noncardiac gastric cancer development. However, the host genetic factors that influence the progression of gastric atrophy have not been elucidated. In this study, we examined the effects of cytokine polymorphisms on H. pylori‐induced gastric atrophy.

Methods.  Blood samples were taken from 454 Japanese subjects. The interleukin‐2 (IL‐2; T‐330G), IL‐4 (C‐33T), and IL‐13 (C‐1111T) polymorphisms were genotyped by polymerase chain reaction with confronting two‐pair primers (PCR‐CTPP). Anti‐H. pylori IgG antibody and pepsinogen I and II were measured to diagnose H. pylori infection and atrophic gastritis.

Results.  The odds ratios (ORs) for the association between IL‐2 polymorphism [OR = 2.78, 95% CI (confidence interval) = 1.26–6.17 (T/T to G/G)] or IL‐4 polymorphism [OR = 2.22, 95% CI = 1.01–4.89 (T/C to C/C)] were increased significantly with gastric atrophy, whereas the corresponding OR of IL‐13 polymorphism was decreased with gastric atrophy [OR = 0.61, 95% CI = 0.39–0.96 (C/T and T/T to C/C)]. There were no significant H. pylori seropositivity‐related differences between these polymorphisms. We examined the relationship between these polymorphisms and gastric atrophy separately in H. pylori‐seropositive and ‐seronegative groups. In the H. pylori‐seropositive group, the IL‐2 T/T (OR = 2.78, 95% CI = 1.12–6.93) had a significant association with gastric atrophy.

Conclusions.  These results reveal that the IL‐2 gene polymorphism is associated with an increased risk of gastric atrophy induced by H. pylori infection and might predispose to gastric cancer.
Effect of Helicobacter pylori Infection on the Expression of DNA Mismatch Repair Protein
Authors: Park Dong Il , Park Seung Ha , Kim Sang Hoon , Kim Jeong Wook , Cho Yong Kyun , Kim Hong Joo , Sohn Chong Il , Jeon Woo Kyu , Kim Byung Ik , Cho Eun Yoon , Kim Eo‐Jin , Chae Seoung Wan , Sohn Jin Hee , Sung In Kyung , Sepulveda Antonia R. , Kim Jae J.
Published: May 2005

Background.  Helicobacer pylori infection is a major gastric cancer risk factor. Deficient DNA mismatch repair (MMR) caused by H. pylori may underlie microsatellite instability (MSI) in the gastric epithelium and may represent a major mechanism of mutation accumulation in the gastric mucosa during the early stages of H. pylori‐associated gastric carcinogenesis. In this study, we examined the expression of DNA MMR protein (hMLH1 and hMSH2) in patients with chronic H. pylori infection before and after eradication of the infection.

Materials and methods.  Gastric tissue samples were collected from 60 patients with H. pylori gastritis and peptic ulcer disease before and after eradication of the infection. The DNA MMR protein expression (hMLH1 and hMSH2) was determined by immunohistochemical staining in 60 patients before and after H. pylori eradication. The percentage of epithelial cell nuclei and intensity of staining were then compared in gastric biopsies before and after eradication.

Results.  The percentage of hMLH1 (76.60 ± 20.27, 84.82 ± 12.73, p = .01) and hMSH2 (82.36 ± 12.86, 88.11 ± 9.27, p < .05) positive epithelial cells significantly increased in 53 patients who became H. pylori‐negative after eradication therapy. However, the intensity of hMLH1 and hMSH2 staining was not significantly different. In those 7 patients, who did not respond to the eradication therapy and were still H. pylori‐positive, the percent positivity and intensity of hMLH1 and hMSH2 staining did not change.

Conclusions.  The expression of DNA MMR proteins increased in the gastric mucosa after H. pylori eradication, indicating that H. pylori gastritis may be associated with a reduced DNA MMR system during infection. The effect of H. pylori infection on MMR protein expression appears to be at least partially reversible after H. pylori eradication. These data suggest that H. pylori gastritis might lead to a deficiency of DNA MMR in gastric epithelium that may increase the risk of mutation accumulation in the gastric mucosa cells during chronic H. pylori infection.
Evaluation of the Homologous Recombination in Helicobacter pylori
Authors: Pyndiah Slovénie , Ménard Armelle , Zerbib Frank , Mégraud Francis
Published: May 2005

Background.  Most strategies for direct mutagenesis of Helicobacter pylori primarily involve genomic DNA cloning which is a time‐consuming and expensive technique.

Methods.  To make a gene replacement, we propose a strategy using polymerase chain reaction (PCR) amplicons to allow a double homologous recombination in the genome of H. pylori. Different strains were used to validate this strategy and we describe how the amplicon insertion was made with accuracy. Moreover, we looked for the shortest homologous sequence needed to allow a specific gene replacement in H. pylori without any deletion, insertion or mutation at the recombination site. All of the experiments were performed at the flaA locus, whose gene encodes the major flagellin.

Results.  Amplicons bearing 500 or 150 bp flanking regions of flaA on each side (depending on the strain) were sufficient to allow the specific insertion of a 1173 bp chloramphenicol cassette into the genome of H. pylori. The insertion was accurate with no substitutions at the insertion locus.

Conclusions.  This information opens the door to other strategies for mutagenesis used for the identification of virulence factors without deleting genes, which would not be based on a negative screening system. For example, they could be useful in performing protein fusion for a better understanding of the virulence factor's mechanism.
Toll‐like Receptor 2‐Mediated Gene Expression in Epithelial Cells During Helicobacter pylori Infection
Authors: Ding Song‐Ze , Torok Anastasia M. , Smith Michael F. , Goldberg Joanna B.
Published: May 2005

Background.  Helicobacter pylori is the major pathogen causing chronic gastritis and peptic ulcer disease and is closely linked to gastric malignancy. We have previously shown that H. pylori‐induced NF‐κB activation and interleukin (IL)‐8 secretion are mediated by Toll‐like receptor (TLR) 2 in epithelial cells. However, the TLR2‐mediated global gene expression profile of the epithelial cell during H. pylori infection is still unknown. The goal of this study was to identify TLR2‐regulated genes in epithelial cells induced by H. pylori.

Materials and methods.  The HEK293 and HEK‐TLR2 cells were cocultured with H. pylori 26695 for 6 hours. Total RNA was extracted and hybridized to the Affymetrix human U133A microarray chipset, which contains 22,283 total probe sets including 14,285 genes. Data analyses were performed using affymetrix suite 5 software. The expression of selected genes in gastric epithelial cells AGS and MKN45 was monitored by quantitative reverse transcriptase‐polymerase chain reaction (RT‐PCR).

Results.  Forty‐six genes, contained in 57 probe sets, were induced > 2‐fold and three genes (five probe sets) decreased > 2‐fold by H. pylori infection of HEK293 cells. Fifty‐four genes, contained in 69 probe sets, were induced > 2‐fold, whereas only 1 gene was repressed > 2‐fold in H. pylori‐infected HEK‐TLR2 cells. Comparisons of genes induced in HEK293 or HEK‐TLR2 cells identified 28 genes whose expression was dependent on the presence of TLR2. Seventeen genes were selected and their expression was assessed using the quantitative RT‐PCR in gastric epithelial cells during H. pylori infection. Eight of the 17 genes showed distinct expression patterns in AGS and MKN45 cells after H. pylori stimulation.

Conclusions.  The current study investigated the TLR2‐mediated global gene changes after H. pylori stimulation in the epithelial cell system. This approach will be helpful in identifying genes whose expression is mediated by specific TLRs and in determining the cellular responses that are responsible for diverse signal pathways during H. pylori infection.
Polymerase Chain Reaction–Restriction Fragment Length Polymorphism Analysis of Clarithromycin‐Resistant Helicobacter pylori Infection in Children Using Stool Sample
Authors: Booka Mina , Okuda Masumi , Shin Kouichirou , Miyashiro Eikichi , Hayashi Hiroko , Yamauchi Koji , Tamura Yoshitaka , Yoshikawa Norishige
Published: May 2005

Background.  To analyze clarithromycin‐resistant Helicobacter pylori infection in children, we developed a method of polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP) analysis using stool samples.

Materials and methods.  Twenty‐three children without significant upper abdominal symptoms were included (mean age 7.0 years). Of these, 18 and five were diagnosed as H. pylori‐positive and ‐negative, respectively, by the H. pylori stool antigen test (HpSA). The DNA from the stool samples was purified using the QIAamp DNA Stool Minikit (QIAGEN). The PCR was performed on the purified DNA using oligonucleotide primers designed to amplify the 23S rRNA gene of H. pylori. The PCR products were reacted with restriction enzymes MboII, BceAI, and BsaI to detect mutations A2142G, A2142C, and A2143G, respectively.

Results.  Sixteen of the 18 HpSA‐positive samples were PCR‐positive, and all five HpSA‐negative samples were PCR‐negative. Thus, the PCR had 89% sensitivity and 100% specificity, with 91% accuracy in reference to HpSA. Of the 16 PCR‐positive samples, one and four were digested with MboII and BsaI, respectively, indicating 31% prevalence of CAM‐resistance.

Conclusions.  We conclude that the PCR–RFLP using stool samples is a rapid and reliable method to noninvasively detect clarithromycin‐resistant H. pylori infection in children. It may be useful before choosing regimens of H. pylori eradication.
Natural Colonization with Helicobacter species and the Development of Inflammatory Bowel Disease in Interleukin‐10‐deficient Mice
Authors: Zhang Li , Danon Stephen J. , Grehan Martin , Chan Vivian , Lee Adrian , Mitchell Hazel
Published: May 2005

Background.  The interleukin‐10‐deficient (IL‐10−/–) mice maintained in specific‐pathogen‐free (SPF) conditions develop typhlocolitis when experimentally infected with Helicobacter species. However, there is limited information regarding the role of Helicobacter species that naturally colonize IL‐10−/– mice in typhlocolitis development. The aim of this study was to examine in SPF IL‐10−/– mice the association between natural colonization specific Helicobacter species and typhlocolitis development.

Material and methods.  Cecum and proximal colon from 72 C57BL/6 × 129/Ola IL‐10−/– mice (8–20 weeks old) were removed for DNA extraction and histologic evaluation. Genus‐specific polymerase chain reaction– denaturing gradient gel electrophoresis (PCR–DGGE) and species‐specific PCR were used to detect Helicobacter species. Mice were grouped by age, sex, and Helicobacter colonization status, and their histologic scores were compared. The development of clinical typhlocolitis was observed in a further 12 mice.

Results.  Species‐specific PCR showed that mice were colonized with Helicobacter ganmani and/or Helicobacter hepaticus. The PCR–DGGE detected H. ganmani, H. hepaticus and an H. ganmani‐like organism. The histologic scores in mice colonized with H. hepaticus were significantly higher than that in mice colonized with H. ganmani. Male mice showed significantly higher histologic scores than female mice. Four of the 12 mice developed clinical typhlocolitis in 38 weeks.

Conclusions.  Natural colonization with different Helicobacter species was found in IL‐10−/– mice within the same breeding colony. The severity of typhlocolitis differed according to the colonizing Helicobacter species. Furthermore, the rate of typhlocolitis development in IL‐10−/– mice naturally colonized with Helicobacter species was significantly slower than that reported in experimentally infected mice.
Inhibitory Effects of Polyphenols on Gastric Injury by Helicobacter pylori VacA Toxin
Authors: Yahiro Kinnosuke , Shirasaka Daisuke , Tagashira Motoyuki , Wada Akihiro , Morinaga Naoko , Kuroda Fuminobu , Choi Oksun , Inoue Masahito , Aoyama Nobuo , Ikeda Mitsuo , Hirayama Toshiya , Moss Joel , Noda Masatoshi
Published: May 2005

Background.  Helicobacter pylori induces gastric damage and may be involved in the pathogenesis of gastric cancer. H. pylori‐vacuolating cytotoxin, VacA, is one of the important virulence factors, and is responsible for H. pylori‐induced gastritis and ulceration. The aim of this study is to assess whether several naturally occurring polyphenols inhibit VacA activities in vitro and in vivo.

Materials and Methods.  Effects of polyphenols on VacA were quantified by the inhibition of: 1, vacuolation; 2, VacA binding to AZ‐521 or G401 cells or its receptors; 3, VacA internalization. Effects of hop bract extract (HBT) containing high molecular weight polymerized catechin on VacA in vivo were investigated by quantifying gastric damage after oral administration of toxins to mice.

Results.  HBT had the strongest inhibitory activity among the polyphenols investigated. HBT inhibited, in a concentration‐dependent manner: 1, VacA binding to its receptors, RPTPα and RPTPβ; 2, VacA uptake; 3, VacA‐induced vacuolation in susceptible cells. In addition, oral administration of HBT with VacA to mice reduced VacA‐induced gastric damage at 48 hours. In vitro, VacA formed a complex with HBT.

Conclusions.  HBT may suppress the development of inflammation and ulceration caused by H. pylori VacA, suggesting that HBT may be useful as a new type of therapeutic agent for the prevention of gastric ulcer and inflammation caused by VacA.
Isogenic Variation of Helicobacter pylori Strain Resulting in Heteroresistant Antibacterial Phenotypes in a Single Host In Vivo
Authors: Lee Yong Chan , Lee Sun‐Young , Pyo Jae Hee , Kwon Dong H. , Rhee Jong Chul , Kim Jae J.
Published: May 2005

Background.  Antibiotic‐susceptible and ‐resistant Helicobacter pylori can be present simultaneously in the same host. The aim of this study was to evaluate the genomic diversity of H. pylori strains resulting in heteroresistant antibacterial phenotypes.

Materials and methods.  Twenty‐one pairs of H. pylori strains isolated from the antrum and body displaying heteroresistant antibacterial phenotypes were included. We compared the genotypes of paired‐isolates by random arbitrarily primed polymerase chain reaction (PCR), flagella gene PCR‐based restriction fragment length polymorphism, and flaA gene sequencing. In metronidazole‐heteroresistant isolates, the sequence variation of rdxA and frxA genes was analyzed using phylogenetic analysis.

Results.  The DNA fingerprinting patterns of the paired isolates revealed that 12 pairs (57.1%) were identical, whereas one pair (3.8%) was different. The remaining eight pairs (38.1%) of isolates showed minor heterogenecity in fingerprinting patterns. In flaA gene sequencing, these identical and similar isolates showed close sequence similarity between the antrum and body, whereas different isolate showed 31 points of different nucleotide sequences. Phylogenetic analysis of the metronidazole‐heteroresistant pairs showed consistent genetic relatedness of each paired isolates despite the sequence variation of the rdxA or frxA genes in five pairs (71.4%).

Conclusions.  These results suggest that continuing genomic diversities in the same strain may play an important role in modulating the antibiotic‐heteroresistant H. pylori in vivo.
Children of Helicobacter pylori‐infected Dyspeptic Mothers are Predisposed to H. pylori Acquisition with Subsequent Iron Deficiency and Growth Retardation
Authors: Yang Yao‐Jong , Sheu Bor‐Shyang , Lee Shui‐Cheng , Yang Hsiao‐Bai , Wu Jiunn‐Jong
Published: May 2005

Background.  We tested whether Helicobacter pylori‐infected dyspeptic mothers had a higher rate of H. pylori infection in their children, and whether such H. pylori‐infected children were predisposed to iron deficiency or growth retardation.

Materials and methods.  A total of 163 children from 106 dyspeptic mothers (58 with and 48 without H. pylori infection) were enrolled to evaluate body weight, height, hemoglobin, serum ferritin, and H. pylori infection using the 13C‐urea breath test. A questionnaire was used to evaluate demographic factors of each child.

Results.  The rate of H. pylori infection in children with H. pylori‐infected dyspeptic mothers was higher than that of children with noninfected mothers (20.5% vs. 5.3%; p < .01, OR: 4.6, 95% CI: 1.5–14.2). The rate of H. pylori infection in children elevated as the number of their H. pylori‐infected siblings increased (p < .01). For children below 10 years of age, H. pylori infection was closely related to low serum ferritin and body weight growth (p < .05).

Conclusion.  The children of H. pylori‐infected dyspeptic mothers had an increased risk for such infection. The risk further increased once their siblings were infected. H. pylori infection in pre‐adolescent children may determine iron deficiency and growth retardation.
Gastric Acidity in Patients with Follicular Gastritis is Significantly Reduced, but Can be Normalized After Eradication for Helicobacter pylori
Authors: Shimatani Tomohiko , Inoue Masaki , Iwamoto Keiko , Hyogo Hideyuki , Yokozaki Michiya , Saeki Toshinari , Tazuma Susumu , Horikawa Yoko , Harada Nobue
Published: May 2005

Background.  Follicular gastritis is thought to be caused by Helicobacter pylori infection. However, the pathophysiology of it remains unclear.

Materials and methods.  We assessed gastric acidity in 15 patients with follicular gastritis, aged 20–37 years, using a 24‐hour intragastric pH‐metry, as well as by histologic and serologic evaluations; and compared it with that in other age‐matched groups: 18 cases of H. pylori‐positive antrum‐predominant gastritis, 12 of pangastritis, and 24 H. pylori‐negative normals. In eight cases with follicular gastritis, it was re‐assessed 6 months after the eradication therapy for H. pylori.

Results.  During nighttime, the percentage of time with intragastric pH above 3.0 in follicular gastritis was significantly higher than that in normals (p < .0001), and in antrum‐predominant gastritis (p < .001), but was comparable with that in pangastritis. In the daytime period, this parameter in follicular gastritis was significantly higher than that in normal (p < .001), in antrum‐predominant gastritis (p < .001), and in pangastritis (p < .05). Marked mononuclear cell and neutrophil infiltration but no apparent glandular atrophy were observed in both the antrum and corpus. Serum pepsinogen I/II ratio was significantly lower in follicular gastritis than that in normals (p < .0001) and in antrum‐predominant gastritis (p < .001), whereas serum gastrin was significantly higher than that in normals (p < .0001), in antrum‐predominant gastritis (p < .01) and in pangastritis (p < .05). After eradication for H. pylori, all of the parameters in follicular gastritis were altered to the same ranges as those in normals.

Conclusions.  In follicular gastritis, gastric acidity is significantly reduced, but can be normalized by eradication of H. pylori. It can thus be speculated that inflammatory cytokines or H. pylori‐infection–induced prostaglandins might strongly inhibit gastric acid secretion in follicular gastritis.
Evolution of the Neuromatrix Theory of Pain. The Prithvi Raj Lecture: Presented at the Third World Congress of World Institute of Pain, Barcelona 2004
Authors: Melzack Ronald
Published: May 2005

Abstract:  The neuromatrix theory of pain proposes that pain is a multidimensional experience produced by characteristic “neurosignature” patterns of nerve impulses generated by a widely distributed neural network—the “body‐self neuromatrix”—in the brain. These neurosignature patterns may be triggered by sensory inputs, but they may also be generated independently of them. Acute pains evoked by brief noxious inputs have been meticulously investigated by neuroscientists, and their sensory transmission mechanisms are generally well understood. In contrast, chronic pain syndromes, which are often characterized by severe pain associated with little or no discernable injury or pathology, remain a mystery. Furthermore, chronic psychological or physical stress is often associated with chronic pain, but the relationship is poorly understood. The neuromatrix theory of pain provides a new conceptual framework to examine these problems. It proposes that the output patterns of the body‐self neuromatrix activate perceptual, homeostatic, and behavioral programs after injury, pathology, or chronic stress. Pain, then, is produced by the output of a widely distributed neural network in the brain rather than directly by sensory input evoked by injury, inflammation, or other pathology. The neuromatrix, which is genetically determined and modified by sensory experience, is the primary mechanism that generates the neural pattern that produces pain. Its output pattern is determined by multiple influences, of which the somatic sensory input is only a part, that converge on the neuromatrix.
Pain: Disease or Dis‐ease? The John Bonica Lecture: Presented at the Third World Congress of World Institute of Pain, Barcelona 2004
Authors: Loeser John D.
Published: May 2005

Abstract:  Chronic pain has only recently been recognized as an important health care issue. There is no widely shared agreement as to the best ways to diagnose and treat chronic pain patients. Pain management is a chaotic component of contemporary medicine. I argue that we need to think of chronic pain as a disease in its own right and develop our specialty of pain management on the basis of evidence for treatment outcomes. The current chaotic state confuses patients, health care providers, and payers. It is possible that pain management may disappear from health care if we do not improve our understanding of chronic pain and how to best treat those who suffer.
Pregabalin for Pain Management
Authors: Gajraj Noor M.
Published: May 2005

Abstract:  Pregabalin is a new analog of the neurotransmitter gamma‐aminobutyric acid (GABA). It is an alpha2‐delta (α2‐δ) ligand that has analgesic, anticonvulsant, and anxiolytic activity. Alpha2‐delta is an auxiliary protein associated with voltage‐gated calcium channels. Pregabalin binds potently to the α2‐δ subunit resulting in modulation of calcium channels and reduction in the release of several neurotransmitters, including glutamate, norepinephrine, serotonin, dopamine, and substance P. This review discusses the pharmacology of this medication as well as available studies in patients.
Thermocoagulation of the Ganglion Impar or Ganglion of Walther: Description of a Modified Approach. Preliminary Results in Chronic, Nononcological Pain
Authors: Reig Enrique , Abejón David , Del Pozo Cristina , Insausti Joaquín , Contreras Rafael
Published: May 2005

Abstract:  The ganglion impar, a single structure usually found at the anterior aspect of the sacrococcygeal joint, is the lowest ganglion of the paravertebral sympathetic chain. Its blockade is indicated in visceral pain syndromes and/or sympathetic pain syndromes of the perineal region. Several approaches to this block have been described, mainly through the anococcygeal or sacrococcygeal ligaments. We propose a modified approach to thermocoagulation of the ganglion impar, using a two‐needle technique, the first one, placed through the sacrococcygeal ligament, the transsacrococcygeal needle, and the second one through a coccygeal disc, the transdiscal needle. The thermocoagulation technique that we employ uses a conventional radiofrequency application of 80°C for 80 seconds through each needle.

In this prospective study, 13 patients with chronic perineal, noncancer‐related pain were followed for a maximum of 6 months. All of these patients underwent diagnostic ganglion impar block with local anesthetic prior to inducing neurodestruction with conventional radiofrequency application, as a positive result to the diagnostic local anesthetic block was a requisite for radiofrequency neurodestruction. We measured pain using a visual analog scale (VAS) before and after treatment. Statistical significance was assessed using the Mann–Whitney U‐test and Wilcoxon range summation test. Initially the VAS was equal to or greater than 7. After therapy the VAS decreased by an average of 50% in the whole group. There were no adverse events.

Our result show that this proposed modified approach to the block and use of radiofrequency for the ganglion impar is useful for the treatment of perineal noncancer‐related pain.
Prediction of the Distance from the Skin to the Lumbar Epidural Space in the Greek Population, Using Mathematical Models
Authors: Stamatakis Emmanouil , Moka Eleni , Siafaka Ioanna , Argyra Erifilli , Vadalouca Athina
Published: May 2005

Background and Objectives:  The skin to lumbar epidural space distance (SLED) is variable, and therefore the ability to clinically predict the SLED may help increase the success of epidural anesthesia/analgesia. The goal of this study was to determine the relationship between the SLED and demographic/anthropometric variables in the Greek population, and develop a mathematical model for its prediction.

Methods:  This prospective randomized study enrolled 406 male and female Greek patients who required an epidural block as part of their anesthetic management. With patients placed in the left lateral and knee‐chest position, the lumbar epidural space was located by the loss of resistance to normal saline technique. Statistical analysis was used to identify the relationship between SLED, and the following variables were evaluated: age, weight, height, body mass index, body surface area, intervertebral space used, pregnancy, and geographic origin within Greece.

Results:  No adverse events or dural punctures occurred. Mean SLED in the general population was 4.98 ± 0.95 cm, with values significantly higher in males (5.37 ± 0.88 cm) compared with females (4.83 ± 0.93 cm). SLED was best associated with weight, body surface area, and body mass index. Mathematical formulae for prediction of SLED in the general population and the female population were derived from linear regression analysis. These formulae were able to predict approximately half of the observed variability in SLED.

Conclusions:  While mathematical models of SLED can be a useful tool, they should not be exclusively relied on in the clinical setting, but rather should be used as an adjunct to standardized techniques to improve the safety and efficacy of epidural anesthesia/analgesia.
A Terror Management Perspective on Ageism
Authors: Martens Andy , Goldenberg Jamie L. , Greenberg Jeff
Published: May 2005

In the present article, we present a theoretical perspective on ageism that is derived from terror management theory. According to the theory, human beings manage deeply‐rooted fears about their vulnerability to death through symbolic constructions of meaning and corresponding standards of value. We extend this perspective to suggest that elderly individuals present an existential threat for the non‐elderly because they remind us all that: (a) death is inescapable, (b) the body is fallible, and (c) the bases by which we may secure self‐esteem (and manage death anxiety) are transitory. We review some recent empirical evidence in support of these ideas and then discuss possible avenues for combating ageism.
This Old Stereotype: The Pervasiveness and Persistence of the Elderly Stereotype
Authors: Cuddy Amy J. C. , Norton Michael I. , Fiske Susan T.
Published: May 2005

Americans stereotype elderly people as warm and incompetent, following from perceptions of them as noncompetitive and low status, respectively. This article extends existing research regarding stereotyping of older people in two ways. First, we discuss whether the mixed elderly stereotype is unique to American culture. Data from six non‐U.S. countries, including three collectivist cultures, demonstrate elderly stereotypes are consistent across varied cultures. Second, we investigate the persistence of the evaluatively‐mixed nature of the elderly stereotype. In an experiment, 55 college students rated less competent elderly targets (stereotype‐consistent) as warmer than more competent (stereotype‐inconsistent) and control elderly targets. We also discuss the type of discrimination—social exclusion—that elderly people often endure.
The Social Separation of Old and Young: A Root of Ageism
Authors: Hagestad Gunhild O. , Uhlenberg Peter
Published: May 2005

Ageism has been the focus of numerous publications, while age segregation is a neglected topic. Ageism on a micro‐individual level is linked to segregation on a macro level in a segregation‐ageism cycle. Possible linking mechanisms, which might help break this cycle, can be found on a meso level of social networks—their structure and functions. Data from the United States and the Netherlands show that non‐family networks are strongly age homogeneous. Based on earlier work by a range of scholars, we suggest that time, group identity, perspective‐taking, and affective ties are factors that must be considered with regard to the functions of networks. Addressing meso level mechanisms poses challenges to social policy as well as research.
Ageism and Age Categorization
Authors: Bytheway Bill
Published: May 2005

Two approaches to defining ageism are discussed. The significance of chronological age, both for bureaucratic procedures and for research, is considered. This demonstrates how birthdays are associated not just with changing status regarding employment and retirement, but also cultural transformations. The relevance of research based on age categories is critically discussed. It is argued that, while such research provides essential evidence of ageism, it inevitably tends to homogenize, particularly when open‐ended “oldest” categories are used. The article concludes with a discussion of four alternative frameworks.
Ageism Across the Lifespan: Towards a Self‐Categorization Model of Ageing
Authors: Giles Howard , Reid Scott A.
Published: May 2005

This article uses this collection of articles on ageism as a springboard to discuss empirical lacunae in the literature as well as propose a self‐categorization model of ageing phenomena. In particular, we argue that research would benefit from a more lifespan communication perspective. This includes the social origins of ageism that can be laid down early in development and perpetuated through collusive
processes as individuals themselves age. Further, problems of interactively managing ageism, its intragenerational parameters, and the variable consequences of making death salient, are identified. Finally, we elaborate and illustrate a self‐categorization model of ageing processes before critically examining panaceas proposed by others to ameliorate ageism.
Balanced Scorecards to Drive the Strategic Planning of Family Firms
Authors: Craig Justin , Moores Ken
Published: May 2005

The focus of this research is the measurement and management tool known as the Balanced Scorecard (BSC) and how it can be applied in the family business context. In this article we add familiness to the four BSC perspectives (financial, innovation and learning, customer, internal process ) and illustrate how this can assist business development, management, and succession planning in family-owned businesses. We use an action research project to highlight how family businesses can professionalize their management by the adoption of a BSC strategy map that includes a family business focus and links the core essence of the family business with the values and the vision of the founder to the strategic initiatives of the family business. The F-PEC Scale constructs of power , experience , and culture are used to introduce a PEC statement that identifies and articulates the core essence of the family business. Finally, we discuss potential contributions that this project has for family businesses and those who work with and for them.
Understanding the Complexities of Private Family Firms: An Empirical Investigation
Authors: Murphy Deborah L.
Published: May 2005

This study extends prior research concerning the perceptions of managers regarding the most important issues facing their firms. Contrary to the evidence gathered on publicly traded companies that shows that ownership issues are deemed most important to financial managers, the most important issues facing private family firms are more short-term in nature. Estate and succession planning become somewhat more important once operational and financial issues are addressed. The results found in this study are robust when firm size, age, survey respondent, and family-firm status are analyzed. Support for commonly accepted family business statistics is found.
The Role of Family Members In Entrepreneurial Networks: Beyond the Boundaries of the Family Firm
Authors: Anderson Alistair R. , Jack Sarah L. , Drakopoulou Dodd Sarah
Published: May 2005

Research has traditionally concentrated on formal kin involvement in the family business. This study investigates if, to what extent, and how entrepreneurs capitalized on resources embedded in the family, but beyond the formal traditionally defined boundaries of the family firm. Employing both quantitative and qualitative approaches, the study finds that about one-quarter of our sample's entrepreneurial network ties were kin, and that most of these worked outside the formal family firm. These ties provided a range of very important resources, both professional and affective in nature. Such beneficial ties extend the family firm without incurring the typical hazards of external linkages.
Sexual dimorphism in angiotensin II-induced hypertension and vascular alterations
Authors: Tatchum-Talom R , Eyster K M , Martin D S
Published: May 2005

Sex differences in the degree of high blood pressure have been described in several forms of experimental animal models of hypertension. However, the influence of sex on angiotensin II-induced hypertension has not been studied. In the present study, we investigated and compared the effects of chronic angiotensin II treatment on blood pressure and vascular function in male and female rats. Chronic treatment with angiotensin II (0.7 mg/kg daily for 10 d) significantly raised arterial blood pressure in male but not female Sprague–Dawley rats; it upregulated the NAD(P)H oxidase gp67 phox subunit in the aorta of male but not female rats; and it exaggerated the vasoconstrictor responses to norepinephrine and serotonin in the mesenteric vascular bed (MVB) of male but not female rats. Vasodilator responses to acetylcholine (ACh) but not papaverine (PPV) or isoprenaline (ISO) were reduced in the MVB of angiotensin II-treated male but not female rats. ACh, but not PPV or ISO dilatory responses were potentiated in the MVB of angiotensin II-treated female rats. The present findings demonstrate that exogenous angiotensin II upregulates aortic NAD(P)H oxidase gp67 phox subunit, and induces hypertension and mesenteric vascular dysfunction only in male rats.Key words: gender, blood pressure, vascular endothelium, angiotensin II hypertension.
The effect of glycosaminoglycans with acetaldehyde on the activation of prothrombin
Authors: Brecher Arthur S , Adamu Mohammed T
Published: May 2005

Heparin17–19k, (25, 50, and 100 ng), heparin6k(50 and 100 ng), heparin3k(50, 100, and 200 µg), chondroitin sulfates B (dermatan sulfate) (0.25, 0.5, and 1.0 µg), C (1 and 10 µg), and A (1 and 10 µg) each prolong the activated partial thromboplastin time (APTT) when preincubated with prothrombin to a greater extent than when preincubated with Factor II-deficient plasma prior to their mixing and subsequent additions of APTT reagent and Ca2+. In all cases statistical significance (p ≤ 0.05) was observed except with the 2 lower levels of heparin3k. These results suggest that the glycosaminoglycans (GAGs) may exert a direct effect upon prothrombin (FII) in their anticoagulant activity. Pre mix tures of [(FII/25 ng H17–19k) + 447 mmol acetaldehyde (AcH)/L] as well as [(AcH/H) + FII] and [(FII/AcH) + H] each exert a synergistic anticoagulant effect upon APTT. At low AcH concentrations (44.7 mmol/L), neither a synergistic nor an additive effect is seen. H6kand H3k, on premixing with 447 mmol AcH/L, exhibit an additive effect on APTT prolongation but no synergism. Similarly, premixtures of CSB/447 mmol AcH/L/FII show a greater anticoagulant effect than do [(CSB/AcH) + FII] or [(FII/AcH) + CSB] premixtures. CSC–AcH and CSA–AcH patterns are analogous to those of CSB (DS). These data suggest the possibility that AcH, the primary product of ethanol metabolism, may serve as a crosslinking adduct with proteins, in this case, prothrombin, as well as GAGs. Thus ternary complexes between the zymogen form of coagulation factors, GAGs, and AcH are possible, further influencing coagulopathy.Key words: prothrombin, alcoholism, acetaldehyde, glycosaminoglycans, heparins, chondroitin sulfates.
Epithelial distribution of neural receptors in the guinea pig small intestine
Authors: Baglole Carolyn J , Davison Joseph S , Meddings Jonathan B
Published: May 2005

Neural and paracrine agents, such as dopamine, epinephrine, and histamine, affect intestinal epithelial function, but it is unclear if these agents act on receptors directly at the enterocyte level. The cellular localization and villus-crypt distribution of adrenergic, dopamine, and histamine receptors within the intestinal epithelium is obscure and needs to be identified. Single cell populations of villus or crypt epithelial cells were isolated from the jejunum of adult guinea pigs. Enterocytes were separated from intraepithelial lymphocytes by flow cytometry and specific binding was determined using fluorescent probes. α1-adrenergic receptors were located on villus and crypt intraepithelial lymphocytes and enterocytes. β-adrenergic receptors were found on villus and crypt enterocytes. Dopamine receptors were found on all cell types examined, whereas histamine receptors were not detected (<10% for each cell population). These studies demonstrated that (1) receptors for epinephrine and dopamine exist on epithelial cells of the guinea pig jejunum, (2) β-adrenergic receptors are found primarily on villus and crypt enterocytes and (3) intraepithelial lymphocytes contain α1-adrenergic, but have few β-adrenergic, receptors. The presence of neural receptors suggests that these agents are acting, at least in part, at the enterocyte or intraepithelial lymphocyte levels to modulate intestinal and immune function.Key words: enterocyte, receptor, intestine, epithelium.
Involvement of the Na+-independent Cl–/HCO3–exchange (AE) isoform in the compensation of myocardial Na+/H+isoform 1 hyperactivity in spontaneously hypertensive rats.
Authors: Farias Fernando , Morgan Patricio , Chiappe de Cingolani Gladys , Camilión de Hurtado María C
Published: May 2005

Enhanced activity of Na+/H+isoform 1 (NHE-1) and the Na+-independent Cl–/HCO3–exchange (AE) is a feature of the hypertrophied myocardium in spontaneously hypertensive rats (SHR). The present study explored the possibility that sustained intracellular acidosis due to increased myocardial acid loading through AE causes NHE-1 enhancement. To this aim, SHR were treated for 2 weeks with a rabbit polyclonal antibody against an AE3 isoform that was recently developed and proven to have inhibitory effects on myocardial AE activity. We then compared the AE activity in the left ventricle papillary muscles isolated from untreated SHR with antiAE3-treated SHR; AE activity was measured in terms of the rate of intracellular pH recovery after an intracellular alkali load was introduced. AE activity was diminished by ~ 70% in SHR treated with the antiAE3 antibody, suggesting that the AE3 isoform is a major carrier of acid-equivalent influx in the hypertrophied myocardium. However, the antibody treatment failed to normalize NHE-1 activity that remained elevated in the myocardium of normotensive rats. The data therefore rule out the possibility that NHE-1 hyperactivity in hypertensive myocardium was due to sustained intracellular acidosis induced by increased AE activity that characterizes SHR myocardial tissue.Key words: NHE-1, AE3, cardiac hypertrophy, myocardial AE activity.
Relating drug-induced changes in carotid artery mechanics to cardiovagal and sympathetic baroreflex control
Authors: O'Leary Deborah D , Steinback Craig D , Cechetto Angela D , Foell Blaine T , Topolovec Jane C , Gelb Adrian W , Cechetto David F , Shoemaker J Kevin
Published: May 2005

Previous evidence indicates that sensitivity of the baroreflex cardiovagal and sympathetic arms is dissociated. In addition, pharmacologic assessment of baroreflex sensitivity (BRS) has revealed that cardiovagal, but not sympathetic, BRS is greater when blood pressure is increasing versus falling. The origin of this hysteresis is unknown. In this study, carotid artery distensibility and absolute distension (diameter) were assessed to test the hypothesis that vessel mechanics in barosensitive regions affect the BRS of cardiovagal, but not sympathetic, outflow. R-R interval (i.e. time between successive R waves), finger arterial blood pressure, muscle sympathetic nerve activity, and carotid artery dimensions (B-mode imaging) were measured during sequential infusions of sodium nitroprusside (SNP) and phenylephrine (PHE). Systolic and diastolic common carotid artery diameters and pulse pressure were recorded to calculate distensibility of this vessel under each drug condition. Cardiovagal BRS was greater when blood pressure was increasing versus decreasing (p < 0.01). Sympathetic BRS was not affected by direction of pressure change. Distensibility did not differ between SNP and PHE injections. However, compared with SNP, infusion of PHE resulted in larger absolute systolic and diastolic carotid diameters (p < 0.001). Therefore, cardiovagal reflex hysteresis was related to drug-induced changes in common carotid artery diameter but not distensibility. The lack of sympathetic hysteresis in this model suggests a relative insensitivity of this baroreflex component to carotid artery dimensions and provides a possible mechanism for the dissociation between cardiovagal and sympathetic BRS.Key words: Oxford method, baroreflex hysteresis, cardiovagal, MSNA, distensibility.
STABILITY OF CRYSTALLINE EVOLUTIONS
Authors: NOVAGA MATTEO , PAOLINI EMANUELE
Published: May 2005

In this paper we analyze the stability properties of the Wulff-shape in the crystalline flow. It is well known that the Wulff-shape evolves self-similarly, and eventually shrinks to a point. We consider the flow restricted to the set of convex polyhedra, we show that the crystalline evolutions may be viewed, after a proper rescaling, as an integral curve in the space of polyhedra with fixed volume, and we compute the Jacobian matrix of this field. If the eigenvalues of such a matrix have real part different from zero, we can determine if the Wulff-shape is stable or unstable, i.e. if all the evolutions starting close enough to the Wulff-shape converge or not, after rescaling, to the Wulff-shape itself.
EXISTENCE OF GLOBAL WEAK SOLUTIONS FOR SOME POLYMERIC FLOW MODELS
Authors: BARRETT JOHN W. , SCHWAB CHRISTOPH , SÜLI ENDRE
Published: May 2005

We study the existence of global-in-time weak solutions to a coupled microscopic–macroscopic bead-spring model which arises from the kinetic theory of diluted solutions of polymeric liquids with noninteracting polymer chains. The model consists of the unsteady incompressible Navier–Stokes equations in a bounded domain Ω ⊂ ℝd, d = 2, 3, for the velocity and the pressure of the fluid, with an extra-stress tensor as right-hand side in the momentum equation. The extra-stress tensor stems from the random movement of the polymer chains and is defined through the associated probability density function which satisfies a Fokker–Planck type degenerate parabolic equation. Upon appropriate smoothing of the convective velocity field in the Fokker–Planck equation, and in some circumstances, of the extra-stress tensor, we establish the existence of global-in-time weak solutions to this regularised bead-spring model for a general class of spring-force-potentials including in particular the widely used FENE (Finitely Extensible Nonlinear Elastic) model.
UTILITIES AND DISTORTIONS: AN OBJECTIVE APPROACH TO POSSIBILITIES CODING
Authors: SGARRO ANDREA
Published: May 2005

We re-take the possibilistic (as opposed to probabilistic) approach to information coding put forward in 1,2. To enhance the possibilistic approach also outside the realm of "subjective" uncertainties, in this paper we adopt an "objective" interpretation of possibilistic source coding based on utility functions and an "objective" interpretation of possibilistic channel coding based on distortion measures and similarity indices. We stress the relationship between possibilistic coding as based on distortions between sequences and algebraic coding as based on minimum distances between codewords. We compute the operational (coding-theoretic) entropy for a new class of possibilistic sources.
ON INEQUALITIES AND CRITICAL VALUES OF FUZZY RANDOM VARIABLES
Authors: YANG LIXING , LIU BAODING
Published: May 2005

It is well-known that Hölder, Minkowski, Markov, Chebyshev and Jensen's inequalities are important and useful results in probability theory. This paper proposes to extend the usefulness of the above inequalities to the context of uncertainty analysis in intelligent systems. In order to further discuss the mathematical properties of fuzzy random variables, the analogous inequalities for fuzzy random variables are first proved based on the chance measure and expected value operator. After that, monotonicity and continuity of critical values of fuzzy random variables are also investigated. Finally, a convergence theorem of critical values for fuzzy random sequence is obtained.
WALKING PEDESTRIAN TRACKING AMONG SEVERAL PEDESTRIANS BY DYNAMIC CAMERA
Authors: CHAMNONGTHAI K. , BOONRAT S.
Published: May 2005

In tracking a walking pedestrian among multiple walking pedestrians by movable camera, the pedestrian-target determination is sometimes mistaken, and it needs real-time image processing. This paper proposes an approach for tracking a walking pedestrian among multiple walking pedestrians with dynamic camera mounted on a pan platform. The objective of this approach is to correctly select the target, and maintain target within field of view. The approach has three processes, consisting of motion extraction, target prediction and camera movement respectively. The motion extraction with background compensation is performed to determine the groups of moving edges. In the target prediction, target position is predicted by using appropriate size window to identify target among several target candidates and to increase the accuracy. The final calculated distance, and direction against target and error are cooperated to determine the predicted target position. At the final process, the camera is moved in order to locate the center of the view at the target center. The experiments were demonstrated by tracking a walking pedestrians at 1 m/s speed and five meters distance from camera. Each experiment roughly consumed 480 ms/frame processing time at 8.5 rev./s motor speed. The results showed that the system error was 5-8% for five walking patterns of a walking pedestrian situation. In the situation of multiple walking pedestrians, the demonstration were performed by tracking a pedestrian among two and three pedestrians, the results revealed that the system succeeded in maintaining the target within the field of view excepting the cases that the movement was suddenly changed in term of direction and speed.