bluuebunny/crossref_metadata_2025_split huggingface dataset:
Absence of residual effects of a defeated resistance gene in poplar
Authors: Woo K.‐S. , Newcombe G. 
Published: December 2004

SummaryIn a few plant pathosystems, defeated major genes have been shown to contribute to partial resistance to disease. This hypothesis has never been tested before in a forest tree, but pathogenic variation associated with recent hybridization in poplar rust in the Pacific northwest provided an opportunity. An F2 progeny of 256 poplar clones in the field near Corvallis, Oregon, USA, has been monitored for rust severity and infection type since the advent of the new hybrid rust, Melampsora × columbiana, in the mid‐1990s. All 256 clones displayed a susceptible infection type in 1997 and again in 2000, and yet variation in uredinial density (i.e. partial resistance) was still observed. To determine which clones possessed a defeated resistance gene, a greenhouse inoculation was performed with an isolate of M. medusae, one of the parents of M. × columbiana. Clones that would have been resistant to M. medusae, prior to the advent of M. × columbiana, were thus identified. The inoculation resulted in a 1 : 1 segregation (χ2=0.772; p=0.38) for resistance, indicating the presence of a major gene. However, the F2 clones possessing the defeated resistance gene displayed the same level of partial resistance in the field in both 1997 and 2000 as their full siblings lacking the gene.
Comparing Chilean and Swedish rust populations: possible impact of long‐distance transport of Melampsora rust
Authors: Hurtado S. , Ramstedt M. 
Published: December 2004

SummaryAs willow (Salix) cultivation grows globally, worldwide monitoring of pathotypes for Melampsora rust, the most serious disease in willow, becomes increasingly important. We compared the pathotype composition of the Melampsora rust population in Chile with that in Sweden and assessed inocula exchange for the rust between the continents. For pathotyping rust isolates, a willow differential was used (a standardized set of willow test clones) to obtain clone‐virulence patterns. These patterns were used to identify virulence components involved in determining which willow clones a given individual pathogen isolate (genotype) can successfully attack. Each virulence component detected earlier in Sweden's rust population was present in Chile's rust population. Using isoenzyme analysis to classify willow species in Chile, a low genetic variation of Salix viminalis (an introduced willow species) was found, compared with the endemic species Salix humboldtiana. Comparison of rust populations for the two countries supports the present hypothesis that intercontinental inocula exchange can be a significant determinant of local pathotype structure, and consequently can be important for willow‐resistance breeding.
Dermatologie an der Universitätsklinik Mbarara, Uganda
Authors: Schmidt Enno , Rose Christian , Mulyowa Grace K. , Jäger Gerold 
Published: December 2004

ZusammenfassungDie Georg‐Klingmüller‐Klinik der Universität Mbarara wurde 1999 eröffnet. Heute werden dort jährlich circa 6 000 ambulante Patienten mit Hautkrankheiten betreut. Vor dem sozioökonomischen Hintergrund eines subsaharischen Landes soll ein Einblick gegeben werden in die Arbeit dieser im Südwesten Ugandas gelegenen Klinik. Neben dem klinischen Spektrum der Dermatosen, der Diagnostik und Therapie wird über die Bedeutung der Dermatologie für die Bekämpfung von HIV/AIDS berichtet. Es wird gezeigt, daß die Kooperation mit Hautkliniken in Deutschland sowohl die Diagnostik in Mbarara erleichtern kann als auch bei uns hilft, den Blick zu schärfen für die zunehmende Zahl von Patienten mit Erkrankungen auf dunkler Haut.
Development and retroviral transduction of porcine neonatal pancreatic islet cells in monolayer culture
Authors: Tatarkiewicz Krystyna , López‐Avalos Maria D. , Yoon Kun‐Ho , Trivedi Nitin , Quickel Robert R. , Bonner‐Weir Susan , Weir Gordon C. 
Published: December 2004

To learn more about the potential of neonatal porcine pancreatic duct and islet cells for xenotransplantation, the development of these cells when cultured as monolayers was evaluated. Immunostaining for islet hormones and cytokeratin‐7 revealed that day eight monolayers consisted of approximately 70% duct cells and less than 10% beta cells. Using Ki‐67 immunostaining as a proliferation marker, the fraction of beta cells in the cell cycle was shown to decrease from 20% at day three to 10% at day eight, and for duct cells from 36 to 19%. Insulin secretion increased 2.4‐fold upon glucose stimulation, and 38‐fold when 10 mm theophylline was added, showing the responsiveness of the neonatal beta cells. Reaggregated monolayers consisted mostly of duct cells, but 4 weeks after transplantation, grafts contained predominantly endocrine cells, with duct cells being almost absent, suggesting in vivo differentiation of duct cells to endocrine cells. Monolayer susceptibility to retroviral transduction was also investigated using a Moloney Murine Leukemia Virus‐based vector. Approximately 60% of duct cells but less than 5% of beta cells expressed the transgene, indicating that precursor duct cells are better targets for transgene expression. These results show that porcine neonatal pancreatic cells can be cultured as monolayers in preparation for transplantation. Furthermore, in such a culture setting, precursor duct cells have a high rate of proliferation and are more efficiently transduced with a retrovirus‐based reporter gene than are beta cells.
Putative intermediate precursor between hematogenic endothelial cells and blood cells in the developing embryo
Authors: Fraser Stuart T. , Ogawa Minetaro , Yokomizo Tomomasa , Ito Yoshiaki , Nishikawa Satomi , Nishikawa Shin‐Ichi 
Published: December 2004

During embryogenesis, endothelial cells are a source of hematopoietic cells. Vascular endothelial (VE)‐cadherin modulates adherens junctions between endothelial cells. How endothelial cells, integrated into the vascular bed via adherens junctions, give rise to free‐floating hematopoietic cells has been examined. Contrary to our previous reports, in this report a cell type simultaneously expressing VE‐cadherin and the hematopoietic marker CD45 was identified, without rigorous enzymatic dissociation of embryonic tissues. In spite of expressing several other endothelial markers such as endothelial cell nitrous oxide synthase (ECNOS) and MECA‐32, this newly defined population failed to produce endothelial colonies when cultured on OP9 stroma, in direct contrast to enzymatically dissociated VE‐cadherin+ cells. When isolated from 9.5 days post coitus (d.p.c.) embryos, VE‐cadherin+ CD45+ cells generated erythroid, myeloid, but not B lymphoid, cells, also in contrast to VE‐cadherin+ cells obtained by enzymatic dissociation. Runx1 null mutant embryos lacked this novel population. Collectively, these results introduce a novel VE‐cadherin+ population within the developing embryo, which may represent an intermediate cell type in the transition of hemogenic endothelial cells into blood.
Expressional changes of ganglioside GM3 during ovarian maturation and early embryonic development in db/db mice
Authors: Kwak Dong Hoon , Jung Kyu Yong , Lee Young Choon , Choo Young Kug 
Published: December 2004

Diabetes and obesity cause abnormal development of reproductive processes in a variety of species, but the mechanisms that underlie this effect have not been fully elucidated. This study examined the expressional changes of ganglioside GM3 during ovarian maturation,in vitrofertilization (IVF) and early embryonic development in diabetic/obese db/db mice. In high‐performance thin‐layer chromatography studies, GM3 expression was conspicuously low in the ovaries of db/db mice compared to non‐diabetic db/+ mice. Signal detected by anti‐GM3 monoclonal antibody was greatly reduced in the primary, secondary and graffian follicles of db/db mice compared to control mice. Results from IVF with ova and sperm from db/db mice showed that GM3 expression during early embryonic development was obviously decreased compared to db/+ mice. This study also elucidated the effects of high glucose (20 and 30 mm) on early embryonic development in ICR strain mice. High glucose caused a decrease in GM3 expression during early embryonic development. Taken together, the results of this study indicate decreased GM3 expression during ovarian maturation and embryonic development of db/db mice, suggesting that alteration of ganglioside expression induced by the diabetic condition may be implicated in the abnormal follicular embryonic development.
Is endoscopic one‐piece mucosal resection essential for early gastric cancer?
Authors: EGUCHI TAKAKO , GOTODA TAKUJI , ODA ICHIRO , HAMANAKA HISANAO , HASUIKE NORIAKI , SAITO DAIZO 
Published: December 2004

Background:  Endoscopic mucosal resection (EMR) is widely accepted as a minimally invasive treatment for early gastric cancer (EGC) in Japan. However, the criteria for EMR must be strictly adhered to otherwise patients will miss the chance for additional therapy. We assess the important factor in expanding the indication of EMR.Methods:  We investigated 1101 EGCs that had been resected by EMR at the National Cancer Center Hospital (NCCH), Tokyo, Japan, according to the indication recommended by Japanese Gastric Cancer Association (JGCA) and the expanded indication proposed by NCCH. Curability and local recurrence of the EMRs were assessed related to the applied indication and the number of resected specimens.Results:  The recurrence rate of non‐evaluable resection was higher than that of evaluable resection (P < 0.0001). Eighty‐three lesions among 772 lesions in the JGCA group were non‐evaluable. Thirty‐seven leisons among 329 lesions in the NCCH group were non‐evaluable. There was no difference in the rate of non‐evaluable resection between JGCA and NCCH groups (P = 0.8329). However, the rate of curative resection was lower in the NCCH group than in the JGCA group (P = 0.0009). In piecemeal resection, there was no difference in the rate of non‐evaluable resection between JGCA and NCCH groups (P = 0.0527). In one‐piece resection, the rate of non‐evaluable resection was lower in the NCCH group than the JGCA group (P = 0.0137).Conclusion:  Based on our series of cases, we propose one‐piece resection as a gold standard for EMR because it enables accurate histological evaluation, even in the EMR, according to the expanded indication.
Analysis of urgent colonoscopy for acute lower intestinal bleeding
Authors: FUJISHIRO HIROFUMI , ADACHI KYOICHI , IMAOKA TOMONORI , KOHGE NARUAKI , KAWAMURA AKIRA , KOMAZAWA YOSHINORI , ONO MASAHIRO , YUKI MIKA , SATO HIROSHI , AMANO YUJI , ISHIHARA SHUNJI , KINOSHITA YOSHIKAZU 
Published: December 2004

Background:  Urgent colonoscopy is often performed to diagnose and stop acute lower intestinal bleeding, but its usefulness has yet to be clarified. The aim of this study was to clarify the present role of urgent colonoscopy for this purpose.Methods  Urgent colonoscopy was defined as colonoscopy performed within 48 h of the occurrence of hematochezia. All patients investigated by urgent colonoscopy from September 1996 to March 2000 who were hospitalized in Shimane Medical University Hospital or Shimane Prefectural Central Hospital, Japan, were enrolled in this study. The endoscopic data and medical records of all the investigated patients were reviewed retrospectively to clarify the role of urgent colonoscopy for diagnosing and treating patients with hematochezia.Results  A total of 152 patients were enrolled and 137 (90.1%) were successfully diagnosed endoscopically. Ischemic colitis was the most frequent disease found (32.9%), followed by postpolypectomy hemorrhage (9.2%), hemorrhoids (8.6%) and rectal ulcer (7.2%). Endoscopic hemostasis was employed to treat postpolypectomy hemorrhage and bleeding rectal ulcers with favorable results.Conclusions  Urgent colonoscopy is useful for the diagnosis of hematochezia. Endoscopic hemostasis is frequently required to treat postpolypectomy hemorrhage and bleeding rectal ulcers.
Identification of quorum‐sensing regulated proteins in the opportunistic pathogen Pseudomonas aeruginosa by proteomics
Authors: Arevalo‐Ferro Catalina , Hentzer Morten , Reil Gerold , Görg Angelika , Kjelleberg Staffan , Givskov Michael , Riedel Kathrin , Eberl Leo 
Published: December 2004

SummaryThe Gram‐negative bacterium Pseudomonas aeruginosa is an opportunistic human pathogen which is responsible for severe nosocomial infections in immunocompromised patients and is the major pathogen in cystic fibrosis. The bacterium utilizes two interrelated quorum‐sensing (QS) systems, which rely on N‐acyl‐homoserine lactone (AHL) signal molecules, to control the expression of virulence factors and biofilm development. In this study, we compared the protein patterns of the intracellular, extracellular and surface protein fractions of the PAO1 parent strain with those of an isogenic lasI rhlI double mutant by means of two‐dimensional gel electrophoresis (2‐DE). This analysis showed that the intensities of 23.7% of all detected protein spots differed more than 2.5‐fold between the two strains. We only considered those protein spots truly QS regulated that were changed in the mutant in the absence of signal molecules but were rescued to the wild‐type situation when the medium was supplemented with AHLs. These protein spots were characterized by MALDI‐TOF peptide mapping. Twenty‐seven proteins were identified that were previously reported to be AHL controlled, among them several well‐characterized virulence factors. For one of the identified proteins, the serine protease PrpL, a biochemical assay was established to verify that expression of this factor is indeed QS regulated. Furthermore, it is shown that the quorum‐sensing blocker C‐30 specifically interferes with the expression of 67% of the AHL‐controlled protein spots of the surface fraction, confirming the high specificity of the compound. Importantly, 20 novel QS‐regulated proteins were identified, many of which are involved in iron utilization, suggesting a link between quorum sensing and the iron regulatory system. Two of these proteins, PhuR and HasAp, are components of the two distinct haem‐uptake systems present in P. aeruginosa. In agreement with the finding that both proteins are positively regulated by the QS cascade, we show that the lasI rhlI double mutant grows poorly with haemoglobin as the only iron source when compared with the wild type. These results add haemoglobin utilization to the list of phenotypes controlled through QS in P. aeruginosa. The surprisingly high number of AHL‐regulated proteins relative to the number of regulated genes suggests that quorum‐sensing control also operates via post‐transcriptional mechanisms. To strengthen this hypothesis we investigated the role of quorum sensing in the post‐translational modification of HasAp, an extracellular protein required for the uptake of free and haemoglobin‐bound haem.
Genetic diversity and population structure of Aeromonas hydrophila, Aer. bestiarum, Aer. salmonicida and Aer. popoffii by multilocus enzyme electrophoresis (MLEE)
Authors: Miñana‐Galbis David , Farfán Maribel , Fusté M. Carme , Lorén J. Gaspar 
Published: December 2004

SummaryGenetic diversity, genetic relationship, identification and population structure of 120 Aeromonas strains (including Aer. hydrophila, Aer. bestiarum, Aer. salmonicida and Aer. popoffii) isolated from various sources were studied by analysis of 15 genetic loci by multilocus enzyme electrophoresis (MLEE). All 15 loci were polymorphic, with an average of 9.4 alleles per locus and a mean genetic diversity (H) of 0.64. Cluster analysis defined at H ≤ 0.7 differentiated most of the taxa analysed except the Aer. popoffii and Aer. bestiarum strains, which showed a close genetic relationship. Allelic frequencies of five loci (EST1, HEX, IDH, LDH1 and MDH) identified 94% of the strains. The index of association (IA) for the total sample was 2.38 and IA values calculated for the different populations were always significantly different from zero. These results suggest that the population structure of this Aeromonas sample is strongly clonal, confirm the taxonomic status of the analysed species in population genetics terms, and show the usefulness of MLEE for identifying Aeromonas species.
The impact of diabetes and obesity on liver histology in patients with hepatitis C
Authors: Friedenberg F. , Pungpapong S. , Zaeri N. , Braitman L. E. 
Published: December 2004

Aim:  An association between diabetes mellitus and HCV has been recognized previously. No study has examined whether there is an independent association between the degree of hepatic fibrosis and the incidence of diabetes in HCV patients when controlling for other risk factors.Methods:  We reviewed the charts of 264 consecutive patients with chronic HCV infection at a referral liver centre from January 1991 to December 1999. Demographic background, medical history, laboratory and liver biopsy results were retrieved.Results:  The prevalence of diabetes was 16.3%. Gender, intravenous drug use, steatosis scores, aminotransferase levels and iron studies were similarly distributed in patients with and without diabetes (all p > 0.05). In contrast, mean age was greater in the diabetic group (49.8 vs. 44.3, p = 0.003). The prevalence of diabetes was substantially higher in African‐Americans (p = 0.001) and those with BMI > 30 (p = 0.015). Although the fibrosis score was higher in diabetics (ρ = 0.14, p = 0.03), that association did not remain significant when controlling for diabetes risk factors (p > 0.3). The degree of steatosis and fibrosis both tended to increase with increasing BMI (ρ = 0.47, p < 0.001 and ρ = 0.13, p = 0.03, respectively). Even after controlling for diabetes, age, gender, race, and current alcohol use, those associations remained (both p < 0.001).Conclusions:  The prevalence of diabetes in our group of HCV patients was high, consistent with other studies. Diabetes is not an independent predictor of degree of fibrosis. Body mass index is an independent predictor of both fibrosis and steatosis in HCV patients.
Comparison of intraperitoneal and posterior subcutaneous abdominal adipose tissue compartments as predictors of VLDL apolipoprotein B‐100 kinetics in overweight/obese men
Authors: Chan D. C. , Watts G. F. , Barrett P. H. R. 
Published: December 2004

Aims:  The influence of different regional adipose tissue (AT) compartments on insulin resistance and dyslipidaemia may account for variations in risk of diabetes and cardiovascular disease. The purpose of this study was to examine the association of intraperitoneal and posterior subcutaneous abdominal AT with very‐low‐density lipoprotein apolipoprotein B‐100 (VLDL‐apoB) kinetics in overweight/obese men.Methods:  Intraperitoneal, anterior subcutaneous and posterior subcutaneous abdominal AT mass (IPATM, ASAATM and PSAATM respectively) were quantified in 51 overweight/obese men using magnetic resonance imaging. Hepatic secretion of VLDL‐apoB was measured using an intravenous infusion of 1‐[13C]‐leucine. Isotopic enrichment of VLDL‐apoB was measured using gas chromatography mass spectrometry and a multicompartmental model used to estimate VLDL‐apoB metabolic parameters. Insulin resistance was estimated by homeostasis model assessment (HOMA) score.Results:  In univariate analysis, IPATM, ASAATM and PSAATM were significantly associated with HOMA score (r = 0.554, 0.425 and 0.440 respectively; p < 0.01). Intraperitoneal abdominal AT mass was also associated with plasma triglycerides (r = 0.292, p < 0.05), VLDL‐apoB concentrations (r = 0.407, p < 0.01) and VLDL‐apoB secretion (r = 0.390, p < 0.05). Intraperitoneal abdominal AT mass remained significantly associated with VLDL‐apoB secretion (r = 0.344, p < 0.05) and HOMA score (r = 0.368, p < 0.01) after adjusting for total body fat. In multiple regression analysis including IPATM, non‐esterified fatty acids and age, IPATM was the best predictor of VLDL‐apoB secretion (R2 = 17%, p < 0.01) and HOMA score (R2 = 32%, p < 0.001). None of the fat compartments were significantly associated with VLDL‐apoB catabolism.Conclusions:  In overweight/obese men the intraperitoneal AT mass is a better predictor of VLDL‐apoB secretion and insulin resistance than either posterior or anterior subcutaneous abdominal AT mass.
Metformin inhibits glycogen synthesis and gluconeogenesis in cultured rat hepatocytes
Authors: Otto M. , Breinholt J. , Westergaard N. 
Published: December 2004

Aim:  Glycogen synthesis, and glucose and lactate production were examined in cultured rat hepatocytes preincubated with metformin (0–500 µm) for 24 h.Methods:  Cells incubated with[1‐13C]‐glucose and [1‐13C]‐lactate allowed us to study the effect of metformin on glucose production from glycogenolysis and gluconeogenesis in a detailed manner using NMR spectroscopy. 1H and 13C‐filtered 1H‐NMR spectra were recorded by using flow‐injection technique.Results:  Metformin decreased glycogen synthesis in a dose‐dependent manner with an IC50 value of 196.5 µm. This effect could not be reversed by the presence of the glycogen phosphorylase inhibitor DAB, suggesting that glycogenolysis was not affected. A clear correlation between glucose production and glycogen content (0.97 < R < 0.99; p < 0.001) and lactate production and glycogen content (0.97 < R < 0.99; p < 0.001) was observed. Moreover, a strong inhibition (62%, p < 0.001) of glucose produced from lactate/pyruvate (3 mm/0.3 mm) was observed in cells treated with 350 µm metformin.Conclusion:  Hepatocytes preincubated for 24 h in the presence of metformin at clinically relevant concentrations showed impaired glycogenesis as well as gluconeogenesis.
Prolonged QTc interval predicts mortality in patients with Type 1 diabetes mellitus
Authors: Rossing P. , Breum L. , Major‐Pedersen A. , Sato A. , Winding H. , Pietersen A. , Kastrup J. , Parving H. ‐H. 
Published: December 2004

SUMMARYAims To evaluate prolonged QTc interval and QT dispersion as predictors of all‐cause and cardiovascular mortality after adjustment for well‐established risk factors in Type 1 diabetic patients.Methods From a cohort of all adult Type 1 diabetic patients, duration of diabetes ≥ 5 years, attending the clinic in 1984 and followed in an observational study for 10 years (n = 939), all subjects with resting baseline electrocardiograms were identified (n = 697, 360 males). The QT length was measured and corrected for heart rate (QTc). Maximal QTc length (QTc max) and QT dispersion were determined.Results At baseline, 431 had normoalbuminuria (< 30 mg/24 h), 138 had microalbuminuria (30–299 mg/24 h) and 128 had macroalbuminuria (≥ 300 mg/24 h) of whom 66 (15%), 35 (25%) and 61 (48%) died during follow‐up, respectively (26 (6%), 14 (10%), 21 (16%) from cardiovascular disease). QTc max. was 442 (1.2) ms (mean (sem)) for survivors and 457 (3.7) in patients who died (P < 0.001). In a Cox proportional hazards model including baseline values of putative risk factors, independent predictors of death were QTc max (P = 0.03), age (P < 0.001), presence of hypertension (P = 0.001), male sex (P < 0.001), log urinary albumin excretion (P < 0.001), smoking (P = 0.04), log serum‐creatinine (P < 0.001), height (P < 0.001), low social class (P = 0.04), whereas QT dispersion, heart rate, and HbA1cwere not included. In the subgroup with macroalbuminuria, but not for all patients, QTc max was an independent risk factor for cardiovascular mortality.Conclusion QTc prolongation, but not increased QT dispersion, is an independent marker of increased mortality in patients with Type 1 diabetes mellitus.