bluuebunny/crossref_metadata_2025_split huggingface dataset:
Zooplankton interactions in an enclosure experiment: insights from stable isotope analyses
Authors: Feuchtmayr H. , Zöllner E. , Santer B. , Sommer U. , Grey J. 
Published: October 2004

Summary1. Density gradients of cladocerans and copepods were generated in an enclosure experiment to compare the impact on the plankton of a filter feeder (Daphnia hyalina × galeata) with that of more selective feeders (calanoid and cyclopoid copepods). The experiment was conducted in situ over 25 days during spring in a mesotrophic lake, Schöhsee, Germany.2. The plankton community was monitored regularly. Daphniids were able to graze on the phytoplankton present, which mainly consisted of small (<1000 μm3) species, whereas copepods did not show any impact on algae.3. At the end of the experiment, Daphnia and remaining cyclopoid copepods were harvested and sorted manually, prior to analyses for stable isotopes of carbon and nitrogen. Daphniids from mesocosms stocked purely with differing densities of Daphnia showed little variability in stable isotope values, whereas those that thrived in enclosure bags together with copepods exhibited lower δ13C values.4. The change in Daphniaδ13C indicates a change of food sources, modified by the presence of the copepods: the higher the mean abundance of copepods in the enclosures, the more 13C‐depleted the daphniids. Increasing abundance of high nucleic acid (HNA) bacteria in the copepod bags may account for the trend in Daphniaδ13C via increased grazing on the bacteria themselves, or via grazing on phytoplankton utilising isotopically light CO2 from respiratory release.5. Cyclopoid copepod stable isotope signatures were related to Daphnia and copepod abundances in copepod bags, suggesting that cyclopoids preyed on the available zooplankton.
Feeding response of the Aldabra giant tortoise (Geochelone gigantea) to island plants showing heterophylly
Authors: Eskildsen Louise I. , Olesen Jens M. , Jones Carl G. 
Published: October 2004

AbstractAim Heterophylly is present in many plant species on oceanic islands. Almost all of these plants are island endemics, and heterophylly may have evolved as a response to feeding from large insular browsers such as giant tortoises and flightless birds. We tested this anti‐browser hypothesis by feeding Aldabra giant tortoises (Geochelone gigantea) with leaves of native Mauritian plants to see if they distinguished between juvenile and adult leaves and between heteophyllous and homophyllous species.Location Mauritius.Methods In a choice experiment we recorded feeding response of four captive Aldabra giant tortoises to 10 species of Mauritian plants, of which seven were heterophyllous and three homophyllous.Results In general, juvenile leaves of heterophyllous species showed convergence in shape and midrib coloration. Homophyllous foliage was preferred to heterophyllous, and among heterophyllous species adult foliage was preferred to juvenile.Main conclusions Several Mascarene heterophyllous plants show convergence in morphology of juvenile leaves and these are avoided by giant tortoises. This indicates a strong selection history from large browsers such as the giant tortoises. The Mascarene example is in accordance with several other comparable cases of plant‐large browser interactions from other archipelagos.
Evolution and phylogeny of the New Zealand cicada genusKikihiaDugdale (Homoptera: Auchenorrhyncha: Cicadidae) with special reference to the origin of the Kermadec and Norfolk Islands' species
Authors: Arensburger Peter , Simon Chris , Holsinger Kent 
Published: October 2004

AbstractAim Determine the phylogeny and dispersal patterns of the cicada genusKikihiain New Zealand and the origin of the Norfolk, Kermadec, and Chatham Island cicadas.Location New Zealand, Norfolk Island, Kermadec Islands and Chatham Island.Methods DNA sequences from 16 species and four soon to be described species of cicadas from New Zealand and Norfolk Island (Australia) were examined. A total of 1401 base pairs were analysed from whole genome extraction of three mitochondrial genes (cytochrome oxidase subunit II, ATPase6 and ATPase8). These DNA sequences were aligned and analysed using standard likelihood approaches to phylogenetic analysis. Dates of divergences between clades were determined using a molecular clock based on Bayesian statistics.Results Most species in the genusKikihiadiverged between 3 and 5 million years ago (Ma) coincident with a period of rapid mountain building in New Zealand. Cicada species on the Kermadec and Norfolk Islands invaded recently from New Zealand and are closely related to the New Zealand North Island speciesKikihia cutora.Main conclusions Speciation in the genusKikihiawas likely due in large part to the appearance of new habitats associated with the rise of the Southern Alps, startingc.5 Ma. Dispersal ofKikihiaspecies within mainland New Zealand probably occurred gradually rather than through long‐distance jumps. However, invasion of Norfolk, the Kermadecs and Chatham Islands had to have occurred through long‐distance dispersal.
Multivariate analysis of a fine‐scale breeding bird atlas using a geographical information system and partial canonical correspondence analysis: environmental and spatial effects
Authors: Titeux Nicolas , Dufrêne Marc , Jacob Jean‐Paul , Paquay Marc , Defourny Pierre 
Published: October 2004

AbstractAim To assess the relative roles of environment and space in driving bird species distribution and to identify relevant drivers of bird assemblage composition, in the case of a fine‐scale bird atlas data set.Location The study was carried out in southern Belgium using grid cells of 1 × 1 km, based on the distribution maps of theOiseaux nicheurs de Famenne: Atlas de Lesse et Lommewhich contains abundance for 103 bird species.Methods Species found in < 10% or > 90% of the atlas cells were omitted from the bird data set for the analysis. Each cell was characterized by 59 landscape metrics, quantifying its composition and spatial patterns, using a Geographical Information System. Partial canonical correspondence analysis was used to partition the variance of bird species matrix into independent components: (a) ‘pure’ environmental variation, (b) spatially‐structured environmental variation, (c) ‘pure’ spatial variation and (d) unexplained, non‐spatial variation.Results The variance partitioning method shows that the selected landscape metrics explain 27.5% of the variation, whilst ‘pure’ spatial and spatially‐structured environmental variables explain only a weak percentage of the variation in the bird species matrix (2.5% and 4%, respectively). Avian community composition is primarily related to the degree of urbanization and the amount and composition of forested and open areas. These variables explain more than half of the variation for three species and over one‐third of the variation for 12 species.Main conclusions The results seem to indicate that the majority of explained variation in species assemblages is attributable to local environmental factors. At such a fine spatial resolution, however, the method does not seem to be appropriated for detecting and extracting the spatial variation of assemblages. Consequently, the large amount of unexplained variation is probably because of missing spatial structures and ‘noise’ in species abundance data. Furthermore, it is possible that other relevant environmental factors, that were not taken into account in this study and which may operate at different spatial scales, can drive bird assemblage structure. As a large proportion of ecological variation can be shared by environment and space, the applied partitioning method was found to be useful when analysing multispecific atlas data, but it needs improvement to factor out all‐scale spatial components of this variation (the source of ‘false correlation’) and to bring out the ‘pure’ environmental variation for ecological interpretation.
The Amazon River as a dispersal barrier to passerine birds: effects of river width, habitat and taxonomy
Authors: Hayes Floyd E. , Sewlal Jo‐Anne N. 
Published: October 2004

AbstractAim  To evaluate the relative effectiveness of the lower and upper sections, respectively, of the Amazon River as a barrier to bird distribution, and to evaluate ecological and taxonomic factors affecting the efficacy of the river barrier.Location  Amazon River of South America between its confluence with the Napo River in the west and its delta in the east.Methods  Using published distribution maps for 448 species of passerine birds occurring along the Amazon River, we evaluated whether each was distributed along one bank only (river presumed to be a barrier) or both banks (no barrier) to test the predictions that the river was more effective as a dispersal barrier: (1) along the lower, wider portion of the river than the upper, narrower portion; (2) for species inhabiting forests than open country; (3) for species inhabiting forest understorey than forest canopy; (4) for species restricted to terra firme (never inundated upland forest) than those not restricted to terra firme and (5) for certain taxonomic groups.Results  Our analyses demonstrated that the Amazon River was most effective as a dispersal barrier along its lower portion and for species restricted to forests and terra firme. However, the river was not significantly more of a barrier for species inhabiting forest understorey than forest canopy. The river was most significant as a barrier to dispersal for the antbirds (Thamnophilidae) and was less significant as a barrier to species belonging to several large families including woodcreepers (Dendrocolaptidae), ovenbirds (Furnariidae), flycatchers (Tyrannidae), cotingids (Cotingidae), tanagers (Thraupidae), seed‐eating finches (Emberizidae) and blackbirds (Icteridae).Main conclusions  The robust widths of Amazonian rivers are widely considered to represent impediments to dispersal and gene flow for many taxa of birds and other animals, and may have represented agents of vicariance in the diversification of species. Our study reaffirms the effectiveness of the lower Amazon River as a current barrier to bird dispersal for forest birds and provides new insights into the effects of habitat and taxonomy on the efficacy of the river barrier. Although supportive of several predictions of the river hypothesis of biological diversification, our study is limited in addressing the historical impact of river barriers as agents of vicariance in the process of diversification.
Clinical features of testicular tumors in children
Authors: KANTO SATORU , SAITO HIDEO , ITO AKIHIRO , SATOH MAKOTO , SAITO SEIICHI , ARAI YOICHI 
Published: October 2004

AbstractAim:  Testicular tumors are not common pediatric solid tumors, especially in Asian children. There have been few reviews of cases in Japan to date. We present the clinical features of 14 pediatric testicular tumor patients.Methods:  Clinical features of 14 testicular tumor patients, such as chief complaints, age at diagnosis, pathology, stages, treatments and prognosis, were examined from medical records. Two patients had their semen tested at adolescence.Results:  Of the 14 prepubescent patients, 12 (85.7%) patients were diagnosed before 3 years of age. Ten cases (71.4%) were diagnosed as yolk sac tumors, three (21.4%) as mature teratomas and one case as an epidermoid cyst. Nine cases (90.0%) among the 10 cases of yolk sac tumor were diagnosed as stage I and one case was stage IV. One stage I yolk sac tumor patient developed lung metastasis later. Eventually, two yolk sac tumor patients died, despite chemotherapy. While all the cases with a diagnosis before 2 years of age survived, 67% (2/3) of cases with a diagnosis after the age of 2 died of tumors. Semen analysis in two patients showed normospermia.Conclusion:  In the present study, the most common testicular tumors were yolk sac tumors and the patients diagnosed before 2 years of age showed favorable results. Age could be a relapse risk factor in yolk sac tumors. Guidelines for handling testicular tumors in children is not yet well established in Japan. An organized system seems necessary to gather and accumulate the results of the cases in Japan in order to develop better guidelines for treatment.
Spoke‐wheel‐like enhancement as an important imaging finding of chromophobe cell renal carcinoma: A retrospective analysis on computed tomography and magnetic resonance imaging studies
Authors: KONDO TSUNENORI , NAKAZAWA HAYAKAZU , SAKAI FUMIKAZU , KUWATA TOMO , ONITSUKA SHIRO , HASHIMOTO YASUNOBU , TOMA HIROSHI 
Published: October 2004

AbstractAim:  Little information has been reported with regard to the radiological features of chromophobe cell renal carcinomas (CCRC). The aim of the present study was to identify imaging characteristics which lead to the histological diagnosis of CCRC.Methods:  The imaging findings of computed tomography (CT) and magnetic resonance imaging (MRI) were retrospectively analyzed in 11 patients with CCRC operated on at Tokyo Women's Medical University, Tokyo, Japan.Results:  None of the factors studied were significant in distinguishing the two variants, typical and eosinophilic variants. Enhanced CT scans showed a spoke‐wheel‐like enhancement with a central scar in 3 patients (27%). The radiological patterns were classified into two groups. Seven patients (64%) showed pattern 1 in which: (i) a hypodense to isodense enhancement compared to the renal medulla in the corticomedullary phase during dynamic CT; (ii) an isodense mass compared to the renal medulla in unenhanced CT scan; and (iii) a lobulated appearance were typically observed. Four patients (36%) showed pattern 2 that seemed to be similar to the features of clear cell carcinoma, having an alveolar structure including a hyperdense enhancement in the corticomedullary phase and an inhomogeneous appearance. A spoke‐wheel‐like enhancement was observed only in patients with pattern 1, and was more clearly demonstrated in larger tumors.Conclusions:  The CT and MRI findings in CCRC patients were not uniform, but it was noted that a spoke‐wheel‐like enhancement with a central stellate scar, which might have been mistaken for oncocytoma, was one of important findings of CCRC. Tumors demonstrating a spoke‐wheel‐like enhancement with a central scar should be carefully managed, because they could be malignant.
Long‐term treatment outcome of tamsulosin for benign prostatic hyperplasia
Authors: ICHIOKA KENTARO , OHARA HIROKI , TERADA NAOKI , MATSUI YOSHIYUKI , YOSHIMURA KOJI , TERAI AKITO , ARAI YOICHI 
Published: October 2004

AbstractBackground:  The present study assessed the long‐term efficacy (>12 months) of tamsulosin in 123 patients with lower urinary tract symptoms caused by benign prostatic hyperplasia (BPH).Methods:  The patients received a starting dose of tamsulosin of 0.2 mg/day, with a further titration up to 0.4 mg/day until symptom relief. Subjective and objective clinical variables were assessed using the international prostate symptom score (IPSS), IPSS quality of life (QoL) score, BPH impact index score, peak urinary flow rate (Qmax) and postvoid residual urine volume.Results:  Except for Qmax, all clinical variables showed significant sustained improvements from baseline throughout the study period (median follow up, 43 months). Thirty patients (24.4%) withdrew because of surgical interventions. The Cox proportional hazards model showed that a baseline IPSS total score ≥15 (HR [hazard ratio] 2.13; 95% CI 1.04–4.34) was predictive of failure for tamsulosin therapy. Furthermore, during the first 12 months, a lowest IPSS total score ≥13 (HR 2.34; 95% CI 1.12–4.89), a lowest IPSS QoL score ≥3 (HR 4.16; 95% CI 1.26–13.68), and a lowest BPH impact index score ≥4 (HR 3.54; 95% CI 1.62–7.75) were also predictive of failure for tamsulosin therapy.Conclusions:  Tamsulosin treatment of BPH patients for more than 12 months showed a sustained, stable efficacy. Patients without short‐term effects were prone to withdraw from tamsulosin therapy, but so did patients with a high baseline IPSS total score, even if therapy was effective for at least 12 months.
Extraperitoneal laparoscopic retroperitoneal lymph node dissection in supine position after chemotherapy for advanced testicular carcinoma
Authors: HARA ISAO , KAWABATA GAKU , YAMADA YUJI , TANAKA KAZUSHI , KAMIDONO SADAO 
Published: October 2004

AbstractAim:  To evaluate the feasibility and usefulness of extraperitoneal laparoscopic retroperitoneal lymph node dissection (RPLND) in the supine position after chemotherapy for advanced testicular carcinomaMethods:  Three patients with advanced testicular cancer underwent chemotherapy. Although serum markers were decreased compared with the normal range, residual masses requiring surgical resection were recognized by computed tomography scanning. We applied extraperitoneal laparoscopic RPLND. The patients were placed in the supine position and the first trocar was inserted two finger widths medial to the anterior iliac spine. The retroperitoneal space was dilated using a preperitoneal distention balloon. Two more ports were inserted into the retroperitoneal space and surgery proceeded thereafter.Results:  The residual tumors were completely resected by laparoscopy. The procedure required 250–310 min and the bleeding volume was below 50 mL. Although the histopathological findings consisted only of necrosis in all of the patients, one patient recurred at the same place.Conclusions:  Extraperitoneal laparoscopic RPLND in the supine position for residual tumors after chemotherapy is technically feasible and useful in terms of postoperative recovery. With regard to cancer control, further evaluation should be necessary.
Overexpression of extracellular signal‐regulated protein kinase and its correlation with proliferation in human hepatocellular carcinoma
Authors: Tsuboi Yasunori , Ichida Takafumi , Sugitani Soichi , Genda Takuya , Inayoshi Jun , Takamura Masaaki , Matsuda Yasunobu , Nomoto Minoru , Aoyagi Yutaka 
Published: October 2004

Abstract: Background: Dysregulation of cell proliferation is one of the most important features of human cancers including hepatocellular carcinoma (HCC). However, the molecular basis underlying the proliferation of HCC has not been fully clarified. Because a previous study reported that overexpression of extracellular signal‐regulated protein kinase (ERK), which transduces extracellular growth stimuli to the nuclei, was frequently observed in several human cancers, this study was performed to analyze the expression of ERK in human HCC and its correlation with HCC proliferation.Methods: Twenty‐four paired samples of primary HCCs and corresponding noncancerous liver tissues, and six samples of histologically normal liver tissue were obtained from surgically resected materials. The expression of ERK was examined by immunoblotting and immunohistochemical analysis. Proliferative activity of each HCC was examined by immunohistochemical demonstration of proliferative cell nuclear antigen (PCNA).Results: The ERK1 and ERK2 expression in HCCs was significantly higher than that in noncancerous liver tissues, and the ERK1 expression in noncancerous liver tissues from patients with HCC was higher than that in tissue from normal liver. Immunohistochemical examination revealed enhanced accumulation of ERK1 in the nuclei of HCC cells. Regression analysis revealed a significant correlation between ERK expression and PCNA labeling index in HCC.Conclusions: Our findings suggest that ERK overexpression contributes to the proliferation of HCC.
Psychoneurological symptoms during interferon therapy in patients with chronic hepatitis: prospective study on predictive use of Cornell Medical Index and electroencephalogram
Authors: Tanaka Yuji , Nagaki Masahito , Tomita Eiichi , Murase Masahiko , Enya Masamichi , Nishigaki Yohichi , Sugihara Jun'ichi , Moriwaki Hisataka 
Published: October 2004

Abstract: Background/Aims: We assessed the usefulness of the Cornell Medical Index (CMI) and electroencephalogram (EEG) in the prediction and early detection of psychoneurological symptoms associated with interferon (IFN) therapy for chronic viral hepatitis.Methods: Forty‐eight consecutive patients received IFN for chronic viral hepatitis for 8–24 weeks. CMI was measured before IFN therapy. Serial EEGs were recorded before IFN therapy, 2, 4 weeks, and thereafter every 4 weeks in the therapy.Results: Psychoneurological symptoms including insomnia, depression, and restlessness were seen in 11 (23%) of 48 patients. Five (13%) of 40 patients with CMI I and II and six (75%) of eight with CMI III developed psychoneurological symptoms (P<0.001). Sensitivity, specificity, and predictive accuracy of CMI III were 55%, 95%, and 75%, respectively. Abnormal EEG such as slow basic rhythm, appeared in 13 patients (27%) during IFN therapy. Psychoneurological symptoms were seen in six (46%) of the 13 patients with abnormal EEG, and in five (14%) of 35 in whom EEG remained normal (P<0.05).Conclusions: CMI is useful for the prediction of IFN‐induced psychoneurological symptoms in patients with chronic viral hepatitis. Serial EEGs contribute to the screening and auxiliarily assessing the adverse effects of IFN on the central nervous system.
Expression of matrix metalloproteinase‐2 and ‐14 persists during early resolution of experimental liver fibrosis and might contribute to fibrolysis
Authors: Zhou Xiaoying , Hovell Christopher J. , Pawley Susannah , Hutchings Matthew I. , Arthur Michael J. P. , Iredale John P. , Benyon R. Christopher 
Published: October 2004

Abstract: Background/Aims: Resolution of liver fibrosis is possible but the identity of the matrix metalloproteinases (MMPs) which degrade the accumulated collagens is uncertain. We examined MMP‐2 and MMP‐14 expression in established and resolving fibrosis to assess their role in resolution of liver fibrosis.Methods: MMP and tissue inhibitor of metalloproteinase (TIMP)‐2 expression in liver extracts was examined by ribonuclease protection assay, Western blotting and gelatin zymography. MMP activity was examined by 14C gelatin degradation.Results: In human cirrhotic liver, MMP‐14 mRNA was increased to 230–330% of normal liver expression. Both 63 kDa proenzyme and 60 kDa activated form were present. Cirrhotic livers had 270–320% of normal liver expression of MMP‐2 protein with 20–25% being the 62 Da activated form. Protein and mRNA for MMP‐2 and MMP‐14 progressively increased during 8 weeks of CCl4 treatment in rats. Between 3 and 7 days of resolution from CCl4 liver fibrosis, MMP‐2 and MMP‐14 persisted at elevated levels. Gelatinolytic activity in liver homogenates peaked at 7 days of recovery, being 140% above that in livers at peak fibrosis.Conclusions: Increased expression and activation of MMP‐2 and ‐14 occurs even under conditions of elevated TIMPs during liver fibrogenesis. During liver fibrosis resolution, as TIMP expression decays, the persistence of MMP‐2 and MMP‐14 may permit collagen degradation.