bluuebunny/crossref_metadata_2025 huggingface dataset:
Retinol (vitamin A) is a cofactor in CD3‐induced human T‐lymphocyte activation
Authors: ALLENDE L. M. , CORELL A. , MADRONO A. , GONGORA R. , RODRIGUEZ‐GALLEGO C. , LOPEZ‐GOYANES A. , ROSAL M. , ARNAIZ‐VILLENA A.
Published: October 2004

Immunomodulatory effects of different retinoids have been demonstrated, both in vivo and in vitro, in different cellular lineages including human and murine thymocytes, human lung fibroblasts, Langerhans' cells, tumoral cells and natural killer (NK) cells; however, any attempt to demonstrate the effect of retinoids on human peripheral blood mononuclear cells (PBMC) resulted in negative results. In the present work, it is shown that retinol and retinoic acid induce a marked increase of proliferation on human PBMC from 32 unrelated healthy individuals, which had previously been stimulated with anti‐CD3 antibodies 48 hr before. Serum‐free medium, specific retinoid concentration (10‐7 M) and a particular timing of retinol addition to the cultures (48 hr after CD3 stimulation) was necessary clearly to detect this retinol‐enhancing effect. The increased proliferative response is specifically mediated via the clonotipic T‐cell receptor–CD3 complex and correlates with the up‐regulation of certain adhesion/activation markers on the T‐lymphocyte surface: CD18, CD45RO and CD25; also Th1‐type of cytokines (interleukin‐2 and interferon‐γ) are found concordantly increased after retinoid costimulation, both measured by a direct protein measurement and by a specific mRNA increase. In addition, it is shown that the in vitro retinol costimulation is only present in immunodeficient patients who have no defect on CD3 molecules and activation pathway. The fact that retinol costimulate lymphocytes only via CD3 (and not via CD2 or CD28) and the lack of response enhancement in immunodeficients with impaired CD3 activation pathway indicates that retinoids may be used as therapeutic agents in immune system deficiencies that do not affect the clonotypic T‐cell receptor.
Cord blood CD4⊃ CD45RA⊃ T cells achieve a lower magnitude of activation when compared with their adult counterparts
Authors: HASSAN J. , REEN D. J.
Published: October 2004

Highly purified CD4+ CD45RA+ cells from cord blood and peripheral blood from healthy adults were studied. The levels of expression of the CD2, CD3, CD4 and CD28 antigens were similar; however, CD45 and CD45RA antigen expression were slightly lower in cord cells. The reduced expression of the CD45RA antigen on cord CD4+ T cells was confirmed in whole blood. Functional assessment revealed deficiencies in cord CD4+ CD45RA+ T cells. Interleukin‐2 (IL‐2) production in response to specific triggering via CD2 monoclonal antibody (mAb) alone, or CD2 mAb in combination with CD28 mAb showed marked underproduction (about 10% of adult production). When CD25 expression was examined, it was observed that the proportion of activated CD4+ CD45RA+ T cells in cord blood was lower than in adult (about 20% of adult expression). Proliferation to CD2 mAbs or CD2+28 mAbs of cord blood naive cells was similarly depressed. Investigation of IL‐2 mRNA expression under these stimulatory conditions paralleled the results observed for CD25 expression, IL‐2 production and proliferation. When phorbol 12‐myristate 13‐acetate (PMA) was added to the cells triggered with CD2+28mAbs, the responses examined were enhanced in both cord and adult blood with no significant differences between the groups. These findings suggest that under identical conditions of stimulation, purified cord blood CD4+ CD45RA+ T cells do not acquire similar activation status as their adult counterparts. These finding may help in understanding the reduced graft‐versus‐host disease (GVHD) observed in cord blood stem cell transplantation.
Comparison of intrahepatic lymphocytes from normal and growth hormone transgenic mice with chronic hepatitis and liver cancer
Authors: HARDY C. L. , BHATHAL P. S. , SNIBSON K. J. , ADAMS T. E.
Published: October 2004

Mice expressing an ovine growth hormone–mouse metallothionein promoter fusion gene (METoGH mice) develop chronic hepatitis which becomes progressively more severe over time, hepatocellular adenomas, and eventually carcinoma in the oldest animals. T‐lymphocyte expression of activation/memory‐associated markers was compared between liver and blood lymphocytes isolated from METoGH and non‐transgenic mice at 7, 10 and 12 months of age. The percentage of intrahepatic lymphocytes (IHL) which were CD4+ was markedly diminished in METoGH mice at all times. CD4+ and CD8+ IHL in METoGH mice expressed Ly‐6A/6D at increased density, and were CD45RBlo at later time‐points. Ly‐6C+ and NK1.1+ CD4+ cells, which are common in normal mouse liver, were found at decreased frequency in METoGH livers. Further analysis demonstrated that, as a proportion of total T‐cell receptor (TCR)αβ cells, NK1.1+ TCRαβint CD4+ cell numbers (NKT cells) were diminished in the livers of METoGH mice. Observations made in METoGH mice support the hypothesis that sustained liver inflammation and hepatocellular injury may be linked to liver cancer. Additionally, it is possible that the relative lack of NKT cells may create an environment permissive for the growth of liver tumours.
Factors that influence spontaneous reporting of adverse drug reactions: a model centralized in the medical professional
Authors: Herdeiro María T. , Polonia Jorge , Gestal‐Otero Juan J. , Figueiras Adolfo
Published: October 2004

Rationale, aims and objectives  The spontaneous reporting of adverse drug reactions (ADRs) through the yellow card and made concrete by the knowledge and attitudes of doctors, has been rousing a great deal of bibliographical interest in recent years. However, there does not seem to be any actual revision in the theme on which the theoretical models that explain the process of decision in reporting are proposed. In this work an explanatory model of the factors that condition reporting is proposed and a revision of the literature on the subject has also been carried out.

Methods  The proposed model is centralized in the medical professional and it considers the habit of reporting as the result of the doctor's formation and his interaction with the environment. The combination of knowledge‐attitudes‐practices and the theory of the satisfaction of needs seemed very adequate for ADR systematization.

Results and conclusions  The results also indicate that, to improve the participation of health professionals in surveillance systems through spontaneous reporting, it might be necessary to design combined strategies that modify both intrinsic (knowledge, attitudes) and extrinsic (relationship between health professionals and their patients, the national health system and pharmaceutical companies) factors.
Prescription‐related illness – a scandalous pandemic
Authors: McGavock Hugh
Published: October 2004

Prescribed drugs are now a major cause of morbidity and mortality, particularly in the elderly. The extent of this pandemic is described and its likely causes in primary care are identified: unnecessary prescribing, imprecise diagnosis, inadequate undergraduate and postgraduate education in pharmacology and therapeutics, the uncritical application of evidence‐based medicine, the outstanding development of new drugs and their sometimes unjustified promotion. Urgent action is recommended under seven headings, by health administration, epidemiologists, medical educators and prescribing doctors.
Molecular investigation of hepatitis E virus infection in domestic and miniature pigs used for medical experiments*
Authors: Tanaka Hozumi , Yoshino Hiroyuki , Kobayashi Eiji , Takahashi Masaharu , Okamoto Hiroaki
Published: October 2004

Abstract:  Background:  Hepatitis E virus (HEV) infection is highly prevalent among domestic pigs in Japan. It has been reported that pig handlers such as farmers and veterinarians are at increased risk of contracting HEV infection. Pigs are regarded as the most acceptable candidate animals for xenotransplantation and, recently, they are being used as experimental animals.

Methods:  We investigated the prevalence of IgG class antibodies to swine HEV (anti‐HEV) and HEV RNA among 152 2‐month‐old domestic pigs and 38 miniature pigs of 4 to 10 months of age that had been brought to our center for medical experiments from five swine farms (A–E) in Japan. Serum samples were tested for anti‐HEV by in‐house enzyme immunoassay, and for HEV RNA by reverse transcription‐polymerase chain reaction using primers targeting the open reading frame 2 (ORF2) region.

Results:  One percent (one of 84), 6% (one of 16), and 38% (20 of 52) of the domestic pigs from farms A, B and C, respectively, had detectable HEV RNA, and the 22 HEV isolates recovered from the viremic pigs were 89.8 to 100% identical to each other in the 412‐nucleotide sequence of ORF2 and segregated into three clusters within genotype 3. Although one pig from farm A had detectable HEV RNA reproducibly, the HEV isolate recovered from this pig was up to 100% similar to those recovered from pigs from farm C, and the sera from all 84 pigs from farm A were negative for anti‐HEV. These results suggested that farm A is free from HEV infection. As the viremic pig from farm A had been raised for 1 month in a barn at our center before serum sampling, it is most likely that the pig acquired HEV infection in the barn at our center where HEV‐viremic pigs from farm C had been reared for several days approximately 3 months earlier. The 38 miniature pigs from farms D and E were negative for both anti‐HEV and HEV RNA. In an attempt to further investigate the prevalence of HEV infection, pigs that were being raised in four swine farms (farms A, C, D, and E) were tested for anti‐HEV. Although 96 (86%) of the 112 pigs from farm C were positive for anti‐HEV, none of the 48 pigs in farm A and 138 miniature pigs in farms D and E was positive for anti‐HEV.

Conclusions:  These results suggest that three of the five swine farms tested were free from HEV, and that periodic testing for anti‐HEV and HEV RNA of pigs used as experimental animals and pigs raised in swine farms from which pigs are purchased, is useful for providing HEV‐free pigs to researchers who are engaged in studies using pigs.
Reference values for clinical chemistry and clinical hematology parameters in baboons
Authors: Schuurman Henk‐Jan , Smith Harold T , Cozzi Emanuele
Published: October 2004

Abstract:  Background:  In vivo xenotransplantation modeling in large animal species is often performed in nonhuman primates, including baboons. For proper data interpretation, reference values for clinical chemistry and hematology are required.

Methods:  These values are available from baseline levels in animals subjected to tolerability/pharmacokinetic studies. For each individual study two tests for clinical chemistry and hematology were performed before the start of treatment.

Results and Conclusion:  We present such data from 17 male and 16 female baboons, with body weights ranging between 4.4 and 14.0 kg (males) and 4.1 and 15.0 kg (females), respectively. The number of duplicate samples per animal determined before each individual study ranged between one and five. These data are reported here to provide baseline values for veterinarians and investigators using baboons in experimental studies, particularly in xenotransplantation.
Public opinion surveys about xenotransplantation
Authors: Hagelin J
Published: October 2004

Abstract: Background: Xenotransplantation may eventually provide a solution to the worldwide shortage of human organs for transplantation. Xenotransplantation is surrounded by profound ethical issues, both for the potential recipients and for the society as a whole. Concurrent with increased scientific interest, there has been an increasing number of quantitative public opinion surveys conducted about xenotransplantation in the last decade. The aim of the present study was to elucidate these surveys, and to assess some factors that may affect the outcome of them.

Materials and methods: Surveys were identified by web and literature searches using key words in Medline and ISI Web of Knowledge. Reference lists of identified surveys were checked. Data was obtained from Inter‐University Consortium for Political and Social Research (ICPSR) and directly from authors whose data were presented in another way than percentages. In total, the present material covered surveys from 35 sources, including 23 countries.

Results and discussion: Results showed that almost half of the respondents accept xenotransplantation, whereas the remaining half did either not accept or did not have/state an opinion. Over time, the proportions of acceptance seemed unchanged. The proportion of those who did not accept decreased and the remaining proportion increased. This pattern was evident in Europe and the US, but not in Japan. Gender and education were found to be associated with opinions to xenotransplantation. The influence of religion was not as straightforward. This may partly depend on how religiosity was measured in the polls. Wording of items influenced levels of acceptance. If a xenotransplant was the ‘‘only choice’’ proportions of acceptance increased, and if a ‘‘risk for zoonotic diseases’’ was stated proportions of acceptance decreased. When wording of survey items was somewhat comparable, there were often, but not always, minor differences in proportions of acceptance between surveys from different sources. Trends in opinions are best measured by the use of the same items. It is however difficult to phrase items that will not be affected by external events.
Effects of inactivation of the lateral pulvinar on response properties of second visual area cells in Cebus monkeys
Authors: Soares JGM , Diogo ACM , Fiorani M , Souza APB , Gattass R
Published: October 2004

1. In the present study, we investigated the influence of the pulvinar nucleus upon response properties of single cells in the second visual area (V2) of Cebus monkeys. The method used consisted of the inactivation of a portion of the lateral pulvinar by GABA injections while studying the response properties of cells in V2 at the same visuotopic location as that of the inactivation.

2. After GABA injection in the pulvinar, most cells in V2 (67%) showed changes in spontaneous and/or stimulus‐driven activities. Contrary to the effect found with inactivation of the striate cortex, which promotes a reduction in the response of V2 neurons, we found that the main effect of pulvinar inactivation was an increment in stimulus‐driven responses of V2 cells (39% of units studied). A reduction of responses was observed in 27% of units.

3. A change in orientation and/or direction selectivity was found in 91% of cells after inactivation of the pulvinar. Most commonly, the orientation selectivity of a neuron was decreased during pulvinar inactivation.

4. The inactivation results indicate that the pulvinar projections have a modulatory effect on the activity of V2 cells.
Changes in endothelium‐derived hyperpolarizing factor in hypertension and ageing: response to chronic treatment with renin–angiotensin system inhibitors
Authors: Goto Kenichi , Fujii Koji , Kansui Yasuo , Iida Mitsuo
Published: October 2004

1. Endothelial function is impaired in hypertension and ageing and this may be associated with an increase in cardiovascular disease. Several clinical studies have shown that blocking the renin–angiotensin system (RAS) improves endothelial function not only in hypertensive patients, but also in normotensive patients with cardiovascular disease.

2. The aim of the present study was to test whether endothelium‐derived hyperpolarizing factor (EDHF)‐mediated smooth muscle hyperpolarization and relaxation are altered in hypertension and ageing and, if so, whether chronic treatment with RAS inhibitors (the angiotensin‐converting enzyme inhibitor enalapril and the angiotensin AT1 receptor antagonist candesartan) would correct such changes.

3. Endothelium‐derived hyperpolarizing factor‐mediated responses were examined in mesenteric arteries from 12‐month‐old spontaneously hypertensive rats (SHR) and 3‐, 6‐, 12‐ and 24‐month‐old normotensive Wistar‐Kyoto (WKY) rats. Furthermore, both strains were treated for 3 months with either RAS blockers or a conventional therapy with hydralazine and hydrochlorothiazide from 9 to 12 months of age.

4. In arteries of 12‐month‐old SHR, EDHF‐mediated responses were impaired compared with age‐matched WKY rats. In SHR, all antihypertensive treatments improved the impairment of EDHF‐mediated responses; however, RAS inhibitors tended to improve these responses to a greater extent compared with conventional therapy with hydralazine and hydrochlorothiazide.

5. In arteries of WKY rats, EDHF‐mediated responses were impaired at the age of 12 and 24 months compared with 3‐ and 6‐month‐old rats, with the response tending to be impaired to a greater extent in 24‐month‐old rats.

6. Three months of treatment of WKY rats, until 12 months of age, with RAS inhibitors, but not with conventional therapy with hydralazine and hydrochlorothiazide, improved the age‐related impairment of EDHF‐mediated responses, despite a similar reduction in blood pressure by both treatments.

7. These findings suggest that: (i) EDHF‐mediated hyperpolarization and relaxation decline with hypertension and ageing in rat mesenteric arteries; (ii) antihypertensive treatment restores the impaired EDHF‐mediated responses in hypertension; (iii) RAS inhibitors may be more efficacious in improving endothelial dysfunction associated with hypertension; and (iv) chronic treatment with RAS inhibitors improves the age‐related impairment of EDHF‐mediated responses, presumably through the blockade of RAS but not blood pressure lowering alone.
Implication of steady state concentrations of nitrite and nitrate metabolites of nitric oxide in plasma and whole blood in healthy human subjects
Authors: Himeno Mariko , Ishibashi Takaharu , Nakano Shigeru , Furuya Keisuke , Yoshida Junko , Kigoshi Toshikazu , Uchida Kenzo , Nishio Matomo
Published: October 2004

1. The aim of the present study was to determine whether the steady state NOx concentration reflects NOx formation in vivo.

2. A NO3– load study was performed after achieving NOx steady state. Chronological changes in NOx concentrations in plasma and whole blood samples from nine healthy subjects were determined by the HPLC–Griess system and NOx concentrations in erythrocytes were estimated as a possible NOx compartment influential in regulating plasma NOx concentrations.

3. Analysis was performed using the first‐order one‐compartment open model and the NOx formation rate was subsequently calculated.

4. The mean (±SEM) steady state NOx concentration of plasma (15.5 ± 1.6 µmol/L), whole blood (12.8 ± 1.2 µmol/L) and erythrocytes (11.9 ± 0.7 µmol/L) did not correlate with the NOx formation rate in the compartments (0.50 ± 0.05, 0.61 ± 0.04 and 0.91 ± 0.17 µmol/kg per h, respectively), whereas a significant correlation was found between the steady state NOx concentration and NOx elimination rate (Kel) in plasma (r = −0.69; P = 0.04) and whole blood (r = −0.79; P = 0.01).

5. Although there was no direct correlation between steady state NOx concentrations and serum creatinine levels, the correlation between half‐life and serum creatinine levels was significant (plasma: r = 0.60, P = 0.02; whole blood: r = 0.49, P = 0.04).

6. Plasma NOx concentrations correlated significantly with erythrocyte NOx concentrations (r = 0.92, P < 0.01; erythrocyte NOx = 0.66 × plasma NOx).

7. The results of the present study indicate that NOx does not accumulate excessively into erythrocytes at steady state and during a NO3– load and that the steady state NOx concentration in whole blood and plasma preferentially implies NOx elimination (mainly depending on renal function) rather than NOx formation.
Effect of Anoectochilus formosanus on fibrosis and regeneration of the liver in rats
Authors: Shih Chun‐Ching , Wu Yueh‐Wern , Hsieh Chang‐Chi , Lin Wen‐Chuan
Published: October 2004

1. The present study examined the effects of an aqueous extract of Anoectochilus formosanus (AFE) on both hepatic fibrosis and regeneration in rats.

2. Fibrosis was induced by intraperitoneal injection of dimethylnitrosamine (DMN) for 3 consecutive days per week for 4 weeks.

3. In DMN‐treated rats, liver cirrhosis‐associated complications, such as liver atrophy, low concentrations of serum albumin and the accumulation of hepatic collagen, were observed. The AFE protected the liver against DMN‐induced fibrosis, as determined by morphological and biochemical observations.

4. In addition, AFE was administered to two‐thirds hepatectomized normal and DMN‐injured rats. Three and 5 days after hepatectomy, AFE increased the extent of liver weight regeneration and the number of S‐phase cells in DMN‐injured rats, but not in normal rats.

5. These results show that AFE seems to be useful in the repair of liver injury, improvement of fibrotic changes and promotion of liver regeneration.
Autoimmune cholangitis in a patient with thymoma
Authors: KIM JANG‐HA , KIM BYUNG‐HO , KIM YOUN‐WHA , PARK JOO‐CHEOL , JUNG YONG HEE , LEE BYOUNG OOK , HAN YO SEB , DONG SEOK HO , KIM HYO JONG , CHANG YOUNG‐WOON , LEE JOUNG IL , CHANG RIN
Published: October 2004

Abstract  Autoimmune cholangitis is characterized biochemically by chronic cholestasis and histopathologically by chronic non‐suppurative destructive cholangitis. It is associated with positive antinuclear antibody test and negative antimitochondrial antibody test results. Recently, we experienced a case of a 35‐year‐old woman with autoimmune cholangitis associated with thymoma who presented with pruritis, jaundice, chronic fatigue and anterior chest discomfort. Her laboratory examinations revealed marked increases in levels of serum alkaline phosphatase and gamma‐glutamyl transpeptidase. In serological tests, antinuclear antibody was found, but antimitochondrial antibody was not. Liver biopsy findings were compatible with chronic non‐suppurative destructive cholangitis. On computed tomography (CT) of the chest, a large anterior mediastinal mass was found. The mass was totally resected and the patient was treated with ursodeoxy cholic acid. Thereafter, her clinical symptoms improved and liver functions completely returned to the normal range. We describe here an uncommon association of autoimmune cholangitis with thymoma, which has not been reported previously in the English‐written literature.
Four years of lamivudine treatment in Chinese patients with chronic hepatitis B
Authors: CHANG TING‐TSUNG , LAI CHING‐LUNG , CHIEN RONG‐NAN , GUAN RICHARD , LIM SENG‐GEE , LEE CHUAN‐MO , NG KENG‐YEEN , NICHOLLS GRAHAM J , DENT JULIE C , LEUNG NANCY WY
Published: October 2004

Background and Aims:  This study assessed the efficacy and safety of up to 4 years of lamivudine treatment and the clinical relevance of the emergence of YMDD‐variant hepatitis B virus (HBV).

Methods:  Fifty‐eight Chinese adult patients with chronic hepatitis B (CHB) were randomized to lamivudine 100 mg/day for up to 5 years and were monitored for YMDD‐variant HBV, hepatitis B e antigen (HBeAg) seroconversion (loss of HBeAg and detectable antibody to HBeAg) and serum alanine aminotransferase (ALT) concentrations. Four‐year data are reported here.

Results:  The rate of HBeAg seroconversion increased with extended therapy and also with higher baseline ALT concentrations. YMDD‐variant HBV was detected in 67% (39/58) of patients at some point during treatment. After 4 years, a total of 47% (27/58) of patients achieved HBeAg seroconversion. Thirty‐three per cent (13/39) of patients with YMDD‐variant HBV achieved HBeAg seroconversion; this increased to 57% (8/14) in patients with moderately elevated (>2–5 × upper limit of normal) pre‐treatment ALT concentrations. The proportion of patients that achieved normal serum ALT increased from 29% (17/58) at baseline to 69% (31/45) following 4 years of treatment. That included 68% (23/34) of patients with YMDD‐variant HBV and 73% (8/11) of those without the variant. All patients receiving lamivudine had reduced serum concentrations of HBV‐DNA compared with baseline, despite the emergence of YMDD‐variant HBV in 39 patients. Lamivudine was generally well tolerated; there was little change in the number or type of drug‐related adverse events in the fourth year of the study.

Conclusions:  Despite the emergence of YMDD‐variant HBV, Chinese patients showed increased HBeAg seroconversion and improvement in ALT levels with an increased duration of treatment with lamivudine.
Role of polymerase chain reaction and liver biopsy in the evaluation of patients with asymptomatic transaminitis: Implications in diagnostic approach
Authors: MADAN KAUSHAL , BATRA YOGESH , PANDA SUBRAT KUMAR , DATTAGUPTA SIDDARTH , HAZARI SIDDARTH , JHA JYOTISH KUMAR , ACHARYA SUBRAT KUMAR
Published: October 2004

Background and Aim:  Detection of an asymptomatic rise in the hepatic aminotransferase (ARHA) value has become a distinct and frequent clinical problem. We evaluated a three‐step diagnostic algorithm in such patients for maximum yield.

Methods:  Consecutive patients with an ARHA value 1.5‐fold the upper limit of normal for at least 4 weeks and who were apparently healthy were included in the study. Each patient underwent standard biochemical investigations and a stepwise investigative protocol. In the first step, serological markers for hepatitis viruses, serum ferritin, 24‐h urinary copper, alpha‐1‐antitrypsin phenotyping, and autoimmune markers were carried out. In step two, patients who tested negative for all the above markers had polymerase chain reaction (PCR) analysis for hepatitis B virus (HBV)‐DNA and hepatitis C virus (HCV)‐RNA. Patients without a diagnosis despite the above investigations underwent a liver biopsy as part of step three.

Results:  Of 105 patients with ARHA, 38 were excluded for various reasons and 67 were included for the final analysis. The mean age was 35.11 ± 11.96 years and 56 patients were men. The mean body mass index was 24.17 ± 3.2 kg/m2. The stepwise diagnostic algorithm achieved a diagnosis in 65/67 (97%) patients. Non‐alcoholic steatohepatitis (NASH) and chronic viral hepatitis were the most common diagnoses, in 24 (36%) patients each. Using the diagnostic algorithm a diagnosis was reached in 34% of patients with only serological and biochemical investigations, whereas PCR for HBV and HCV could further detect the presence of active HBV or HCV viremia in 21% (14/97) and a liver biopsy was necessary to establish the diagnosis in 28/67 (42%) patients.

Conclusions:  A stepwise diagnostic algorithm in patients with ARHA resulted in an optimal use of PCR and invasive tests such as liver biopsy. Cryptic HBV and HCV infection was frequent among these patients and PCR was necessary in such cases. NASH and chronic viral hepatitis were the most frequent causes of ARHA.
Gene expression analysis in the stomachs of water immersion‐restraint stress rats using high‐density oligonucleotide array
Authors: MIZUNO SHIGEAKI , KATO KIMITOSHI , ASAI SATOSHI , TAKAHASHI YASUO , NAGATA TOSHIHITO , KOMURO SACHIKO , IWASAKI ARIYOSHI , ISHIKAWA KOICHI , ARAKAWA YASUYUKI
Published: October 2004

Background and Aim:  Research on gastric lesions developing in response to stress is essential to elucidating the pathogenesis of these lesions as well as the interplay with other factors, including Helicobacter pylori infection and non‐steroidal anti‐inflammatory drug use. Genes expressed individually or in sets, such as heat shock proteins, growth factors, proto‐oncogenes and cyclooxygenases, have been investigated in the stomach. However, gene expression in the stomach after stress exposure have not yet been comprehensively examined. We investigated the gastric gene expression profile in response to stress.

Methods:  A high‐density oligonucleotide array, representing approximately 850 genes, was used to determine gene expression changes in the stomachs of water immersion‐restraint stress (WIRS) rats.

Results:  Fifty‐eight genes including expressed sequence tag (EST) genes were upregulated more than twofold in the 30 min‐WIRS rat stomach as compared with the control. Concomitantly, five genes were downregulated. Numbers of up‐ or downregulated genes decreased rapidly at 1 and 2 h of WIRS. Altered gene expression of heat shock proteins, cell cycle regulators, proto‐oncogenes and metabolic enzymes were recognized. Several of these genes, including p38 mitogen‐activated protein kinase, did not reportedly show gastric expression changes in response to stress.

Conclusion:  These results suggest that, in addition to the previously identified stress‐induced genes, expression of a number of other genes in the stomach is also involved in stress response.
Antralization of gastric incisura is topographically associated with increased gastric epithelial apoptosis and proliferation, but not with CagA seropositivity
Authors: XIA HARRY HUA‐XIANG , WONG BENJAMIN CHUN‐YU , ZHANG GUI‐SHUI , YANG YI , WYATT JENNY MA , ADAMS STUART , CHEUNG KAREN , LAM SHIU KUM , TALLEY NICHOLAS J
Published: October 2004

Background and Aims:  Helicobacter pylori infection is linked with increased antralization at the gastric incisura. The present study aimed to determine if antralization is associated with altered gastric epithelial apoptosis and proliferation and with seropositivity of the cytotoxin‐associated gene product A (CagA) of H. pylori.

Methods:  Gastric biopsies taken from the antrum, incisura, body and fundus of 75 patients (34 male, 41 female; mean age 59.5 years) were used for diagnosis of H. pylori infection and assessments of histological changes. Apoptosis and Ki‐67 expression in epithelial cells were determined for the antral, incisura and body biopsies by immunohistochemistry. Serum samples were tested by enzyme‐linked immunosorbent assays for anti‐H. pylori and anti‐CagA IgG antibodies.

Results:  Apoptotic index (AI) and Ki‐67 proliferation index (PI) were greater in the presence (vs absence) of H. pylori infection at the antrum, incisura and body (all P < 0.001), and topographically associated with chronic gastritis and gastric atrophy/intestinal metaplasia at the antrum and incisura (all P < 0.001). Moreover, AI and PI were greater in the presence (vs absence) of antralization at the incisura (20.2 ± 0.9 vs 11.4 ± 0.1.1 and 48.9 ± 2.5 vs 29.9 ± 2.5, both P < 0.001). CagA seroprevalence was 41% in the 39 infected patients. CagA seropositivity was associated with gastric atrophy/intestinal metaplasia at the antrum (χ2 = 4.67, P = 0.03) and incisura (χ2 = 4.88, P = 0.03), but not associated with gastric epithelial apoptosis and Ki‐67 expression, nor with antralization at the incisura.

Conclusions:  Antralization of gastric incisura is topographically associated with increased gastric epithelial apoptosis and proliferation, but not with CagA seropositivity.
Investigations on epiphytic living Pseudomonas species from Malus domestica with an antagonistic effect to Venturia inaequalis on isolated plant cuticle membranes
Authors: Singh Prikhshayat , Piotrowski Markus , Kloppstech Klaus , Gau Achim E.
Published: October 2004

In order to understand better the survival and mutual interaction of epiphytic bacteria and fungi on apple plants, bacteria collected from these plants were cultivated on intact adaxial, stoma free cuticle membranes originally obtained from apple. The bacteria were labelled with luciferase genes from Vibrio harveyi in order to follow up their development and activity on the isolated cuticles. Our finding was that the epiphytic bacteria can have access to nutrients below the cuticle without causing damage to these cuticular membranes. Bacterial proteins may enable this nutrient mobilization and we found, indeed, that more than 46 proteins that must have been delivered by the bacteria in response to interaction with the cuticles as they could be found below the cuticle membrane. Eight major representatives of this group of external proteins have been sequenced with electron spray quadrupole time of flight mass spectrometry and subsequently identified by data base homology search as a flagellin, a porin type protein and proteins that are involved in amino acid recruitment and metabolism.
Acetoclastic and hydrogenotrophic methane production and methanogenic populations in an acidic West‐Siberian peat bog
Authors: Kotsyurbenko Oleg R. , Chin Kuk‐Jeong , Glagolev Mikhail V. , Stubner Stephan , Simankova Maria V. , Nozhevnikova Ala N. , Conrad Ralf
Published: October 2004

Sites in the West Siberian peat bog ‘Bakchar’ were acidic (pH 4.2–4.8), low in nutrients, and emitted CH4 at rates of 0.2–1.5 mmol m−2 h−1. The vertical profile of δ13CH4 and δ13CO2 dissolved in the porewater indicated increasing isotope fractionation and thus increasing contribution of H2/CO2‐dependent methanogenesis with depth. The anaerobic microbial community at 30–50 cm below the water table produced CH4 with optimum activity at 20–25°C and pH 5.0–5.5 respectively. Inhibition of methanogenesis with 2‐bromo‐ethane sulphonate showed that acetate, phenyl acetate, phenyl propionate and caproate were important intermediates in the degradation pathway of organic matter to CH4. Further degradation of these intermediates indicated that 62–72% of the CH4 was ultimately derived from acetate, the remainder from H2/CO2. Turnover times of [2‐14C]acetate were on the order of 2 days (15, 25°C) and accounted for 60–65% of total CH4 production. Conversion of 14CO2 to 14CH4 accounted for 35–43% of total CH4 production. These results showed that acetoclastic and hydrogenotrophic methanogenesis operated closely at a ratio of approximately 2 : 1 irrespective of the incubation temperature (4, 15 and 25°C). The composition of the archaeal community was determined in the peat samples by terminal restriction fragment length polymorphism (T‐RFLP) analysis and sequencing of amplified SSU rRNA gene fragments, and showed that members of Methanomicrobiaceae, Methanosarcinaceae and Rice cluster II (RC‐II) were present. Other, presumably non‐methanogenic archaeal clusters (group III, RC‐IV, RC‐V, RC‐VI) were also detected. Fluorescent in situ hybridization (FISH) showed that the number of Bacteria decreased (from 24 × 107 to 4 × 107 cells per gram peat) with depth (from 5 to 55 cm below the water table), whereas the numbers of Archaea slightly increased (from 1 × 107 to 2 × 107 cells per gram peat). Methanosarcina spp. accounted for about half of the archaeal cells. Our results show that both hydrogenotrophic and acetoclastic methanogenesis are an integral part of the CH4‐producing pathway in acidic peat and were represented by appropriate methanogenic populations.
Evaluating single‐base‐pair discriminating capability of planar oligonucleotide microchips using a non‐equilibrium dissociation approach
Authors: Li Emily Sze Ying , Ng Johnson Kian Kok , Wu Jer‐Horng , Liu Wen‐Tso
Published: October 2004

The capability of planar rRNA‐based oligonucleotide microarrays for single‐base‐pair discrimination was evaluated using an approach that compares the non‐equilibrium dissociation profiles and dissociation temperatures (Tds) of all probe‐target duplexes simultaneously. Three sets of 16S rRNA gene specific probes at different levels of specificity were used along with their counter probes for individual sets having either one or two mismatches (MM) to their targets at specific external (next to terminus) and various internal positions. Criteria based on the Td approach and a discrimination index (DI) were proven to be competent in discriminating PM from internal MM duplexes, but not always for external MM duplexes. Maximal DI for separating PM duplexes from ones with two and one internal MM usually occurred at temperatures approximately 5–10°C and 10–15°C, respectively, higher than the Tds of the PM duplexes. Washing buffer type and salt concentration, and MM number and position were shown statistically to affect dissociation profiles, Td, and single‐base‐pair discriminating capability. The reusability potential of the planar microchip was further demonstrated.
High glucose mediates pro‐oxidant and antioxidant enzyme activities in coronary endothelial cells
Authors: Weidig P. , McMaster D. , Bayraktutan U.
Published: October 2004

Aim:  Excess levels of free radicals such as nitric oxide (NO) and superoxide anion (O2–) are associated with the pathogenesis of endothelial cell dysfunction in diabetes mellitus. This study was designed to investigate the underlying causes of oxidative stress in coronary microvascular endothelial cells (CMECs) exposed to hyperglycaemia.

Methods:  CMECs were cultured under normal (5.5 mmol/l) or high glucose (22 mmol/l) concentrations for 7 days. The activity and expression (protein level) of endothelial NO synthase (eNOS), inducible NOS (iNOS), NAD(p)H oxidase and antioxidant enzymes, namely, superoxide dismutase (SOD), catalase and glutathione peroxidase (GPx) were investigated by specific activity assays and Western analyses, respectively, while the effects of hyperglycaemia on nitrite and O2– generation were investigated by Griess reaction and cytochrome C reduction assay, respectively.

Results:  Hyperglycaemia did not alter eNOS or iNOS protein expressions and overall nitrite generation, an index of NO production. However, it significantly reduced the levels of intracellular antioxidant glutathione by 50% (p < 0.05) and increased the protein expressions and activities of p22‐phox, a membrane‐bound component of pro‐oxidant NAD(p)H oxidase and antioxidant enzymes (p < 0.05). Free radical scavengers, namely, Tiron and mercaptopropionylglycine (MPG) (0.1–1 µmol/l) reduced hyperglycaemia‐induced antioxidant enzyme activity and increased glutathione and nitrite generation to the levels observed in CMEC cultured in normoglycaemic medium (p < 0.01). The differences in enzyme activity and expressions were independent of the increased osmolarity generated by high glucose levels as investigated by using equimolar concentrations of mannitol in parallel experiments.

Conclusions:  These results suggest that hyperglycaemia‐induced oxidative stress may arise in CMEC as a result of enhanced pro‐oxidant enzyme activity and diminished generation of antioxidant glutathione. By increasing the antioxidant enzyme capacity, CMEC may protect themselves against free radical‐induced cell damage in diabetic conditions.
Variants in the human β1‐,β2‐ and β3‐adrenergic receptor genes are not associated with morbid obesity in children and adolescents
Authors: Tafel J. , Branscheid I. , Skwarna B. , Schlimme M. , Morcos M. , Algenstaedt P. , Hinney A. , Hebebrand J. , Nawroth P. , Hamann A.
Published: October 2004

Aim:  β‐adrenergic receptors (β‐ARs) are of key importance for the regulation of lipolysis and thermogenesis by catecholamines. Genetic defects in expression or function of β1‐ β2‐ and/or β3‐AR could affect energy homeostasis and predispose an individual towards the development of obesity. We therefore investigated the possible association of polymorphisms in the β‐adrenergic receptor genes with early onset obesity.

Methods:  Frequencies of the following variants were assessed in extremely obese children and healthy underweight controls: Gly/Ser in codon 49 and Arg/Gly in codon 389 of the β1‐AR, Arg/Gly in codon 16 and Gln/Glu in codon 27 of the β2‐AR, Trp/Arg in codon 64 of the β3‐AR.

Results:  The Ser49 allele in the β1‐AR gene was found at a frequency of 0.131 in obese and 0.136 in lean subjects (p = 0.835), while the Gly389 allele in the β1‐AR had a frequency of 0.319 in obese and 0.328 in lean subjects (p = 0.802). Gly16 in the β2‐AR was found with a frequency of 0.590 in obese and 0.611 in lean subjects (p = 0.591) and the Glu27 allele in the β2‐AR had a frequency of 0.380 in obese and 0.420 in lean subjects (p = 0.298).

Conclusion:  We did not detect significant differences for allele and carrier frequencies of individual polymorphisms. Together with previously obtained data on genotype distribution of a β3‐AR variant in the same study group, no significant differences were found between obese and lean subjects for the distribution of individuals with variants in none, one, two or all three β‐ARs. Our data make it unlikely that polymorphisms in β‐ARs are involved in the pathogenesis of early onset obesity.
Antioxidant vitamins C and E ameliorate hyperglycaemia‐induced oxidative stress in coronary endothelial cells
Authors: Ülker S. , McMaster D. , McKeown P. P. , Bayraktutan U.
Published: October 2004

Objective:  Vitamins C and E have protective features in many disease states associated with enhanced oxidative stress. The aim of this study was to investigate whether vitamin(s) C and/or E modulate hyperglycaemia‐induced oxidative stress by regulating enzymatic activities of prooxidant, i.e. NAD(P)H oxidase and/or antioxidant enzymes, namely endothelial nitric oxide synthase (eNOS), superoxide dismutase, catalase and glutathione peroxidase, using coronary microvascular endothelial cells (CMEC).

Methods:  CMEC were cultured under normal (5.5 mm) or high glucose (22 mm) concentrations for 7 days. The enzyme activities were determined by specific assays. The levels of O2– and nitrite were measured by cytochrome c reduction and Griess assays respectively.

Results:  Hyperglycaemia did not alter eNOS activity or overall nitrite generation, an index of NO production. However, it increased NAD(P)H oxidase and antioxidant enzyme activities (p < 0.05). Specific inhibitors of NAD(P)H oxidase, i.e. phenylarsine oxide (0.1–3 µm) and 4‐(2‐aminoethyl)benzenesulfonyl fluoride (5–100 µm) and vitamins C and E (0.1–1 µm) significantly reduced prooxidant and antioxidant enzyme activities in CMEC exposed to hyperglycaemia (p < 0.01). The differences in enzyme activities were independent of increases in osmolarity generated by high glucose levels as investigated by using equimolar concentrations of mannitol in parallel experiments.

Conclusions:  Vitamins C and E may protect CMEC against hyperglycaemia‐induced oxidative stress by concomitantly regulating prooxidant and antioxidant enzyme activities.
Nerve growth factor and vanilloid receptor expression, and detrusor instability, after relieving bladder outlet obstruction in rats
Authors: Kim Joon Chul , Kim Doo Bae , Seo Seong II , Park Yong Hyun , Hwang Tae‐Kon
Published: October 2004

OBJECTIVE

To investigate mRNA expression for nerve growth factor (NGF) and vanilloid receptor TRPV1 in the bladder after relieving bladder outlet obstruction (BOO), and to correlate changes with functional changes of the bladder.

MATERIALS AND METHODS

Temporary BOO was induced by partial urethral ligation in 40 male Wistar rats. After 3 weeks the obstruction was removed and the rats assessed by cystometry 3 weeks later. The bladder body of each rat was then removed, and NGF and TRPV1 mRNA expression measured by the reverse transcription‐polymerase chain reaction. Fifteen sham‐operated rats served as controls.

RESULTS

Based on the cystometry, 10 of the 40 experimental rats were judged to have an unstable bladder, and the remaining 30 to have normal bladder function. The mean bladder weight in the normal and unstable groups was higher than in the control group, and there was no significant difference between the normal and unstable groups. The bladder contraction pressure was similar in the three groups but the mean contraction interval was markedly shorter in the unstable than in the control and normal groups (P < 0.05). The mRNA expressions of NGF and TRPV1 were higher in the unstable than in the control and normal groups.

CONCLUSIONS

NGF and TRPV1 were apparently increased in unstable bladder tissue after relieving BOO; these changes may be related to irritative symptoms after correcting BOO.
Upper tract surveillance in primary bladder cancer follow‐up
Authors: Enver Mohamed K. , Miller Paul D. , Chinegwundoh Frank I.
Published: October 2004

OBJECTIVE

To determine if there is national variation in regimens of upper urinary tract surveillance in patients with primary bladder cancer.

METHODS

A questionnaire was sent to 470 consultant urologists from a British Association of Urological Surgeons list in the UK; 301 anonymous replies were received. Two replies were incomplete and therefore the results of 299 questionnaires (64%) were analysed.

RESULTS

Of the 299 surgeons, 19 (6%) use no form of upper urinary tract surveillance; 162 (54%) use surveillance in selected patients, i.e. those with carcinoma in situ (47%), multiple bladder tumours at first presentation (39%) and after cystectomy (70%), and 118 (39%) use upper tract surveillance on all patients with a history of bladder cancer. The median (range) screening interval was 24 (12–60) months and surveillance continued for a median of 10 (2 to indefinite) years, continuing for an indefinite period in 33%.

CONCLUSIONS

Most urologists use upper tract surveillance in patients with bladder cancer but there is wide variation in the duration and interval for which it continues, and in the type of patient selected for surveillance. Some patients at high risk of upper tract tumour are not being screened. Asymptomatic upper tract tumours may not be diagnosed because the intervals between surveillance are too long, and the duration for which it continues inadequate. There is a need for multidisciplinary national guidelines to reduce variation in practice.
Salvage cystectomy after failure of interstitial radiotherapy and external beam radiotherapy for bladder cancer
Authors: Nieuwenhuijzen Jakko A. , Horenblas Simon , Meinhardt Wim , Van Tinteren Harm , Moonen Luc M.F.
Published: October 2004

OBJECTIVE

To evaluate the long‐term results of salvage cystectomy after interstitial radiotherapy (IRT) and external beam radiotherapy (EBRT) for transitional cell carcinoma, and to assess the morbidity and functional results of the different urinary diversions used.

PATIENTS AND METHODS

The records of 27 patients treated with salvage cystectomy in one institution between 1988 and 2003 were retrospectively analysed.

RESULTS

Salvage cystectomy was used after failure of IRT in 14 or EBRT in 13 patients, with a 3‐ and 5‐year survival probability of 46% (95% confidence interval 26–65) and 33 (11–54)%. The 5‐year overall survival after cystectomy was 54% after IRT and 14% after EBRT (P = 0.12). Tumour category, response to radiation, American Society of Anesthesiology score, and complete tumour resection had a significant influence on survival. Five of seven patients with incomplete resection died because of local disease, with a median survival of 5 months. There was clinical understaging after radiotherapy in 41% of patients. Nine patients had an orthotopic neobladder, with complete day‐ and night‐time continence in eight and four, respectively. All patients but one had good voiding function. There were early complications in two and late complications in six patients (for Bricker, seven of 14 and none; for Indiana, none of four and two of four). The duration of hospitalization was not influenced by the type of diversion. Erectile function was maintained in four of six patients after a sexuality‐preserving cystectomy and neobladder.

CONCLUSIONS

Salvage cystectomy can be performed with acceptable morbidity using any type of urinary diversion. Understaging after radiotherapy is common, but preoperative selection needs improving. A very significant factor for an adverse outcome and death from local tumour recurrence was incomplete resection, suggesting that salvage cystectomy should only be attempted if complete resection is probable.