bluuebunny/crossref_metadata_2025 huggingface dataset:
An integrated environment for developing knowledge‐based spatial decision support systems
Authors: ZHU XUAN
Published: March 2007

Knowledge‐based spatial decision support systems (KBSDSS) incorporate heuristic reasoning, and analytical and spatial modelling capabilities to support decision making in resource and environmental management. They are able to provide the assistance for both the structuring and formulation of the spatial problem, and the design and execution of a solution process by automatically integrating different types of models and data. This paper presents a KBSDSS development environment, which connects a GIS tool (ARC/INFO) with an expert system tool (CLIPS) and a hypertext diagramming tool (HARDY). ARC/INFO provides capabilities for spatial data handling. CLIPS is used to develop knowledge bases and heuristic reasoning. HARDY is used to represent spatial problems in terms of diagrams that can then be translated into a CLIPS knowledge base for evaluation. The development environment allows users to structure their problems and develop models for particular requirements and domains.
Designing and implementing a GIS in an international context
Authors: PANTAZIS DIMOS N , CORNÉLIS BERNARD
Published: March 2007

International collaborations between private companies, national research laboratories, and universities in the field of GIS have opened up new ways of exchanging knowledge and experiences between different countries. However, when a collaboration involves the actual design and implementation of an operational GIS, rather than simply theoretical or applied research, or the development of specific applications, many problems can arise, sometimes leading either to the partial success or to the complete failure of a project. Some of these problems are frequently encountered in all kinds of international collaborations: problems arising from different cultural mentalities, difficulties establishing a single common leadership, difficulties with communication and information exchange, and so on. Problems relating to the specific nature of GIS are also present, for example the absence of digital geographic data format standards, the absence of metadata standards, the omission of GIS or IS design methods, etc. This paper focuses on a joint Sino‐Belgian project for the design and implementation of an urban geographical information system (UGIS) integrating remote sensing techniques in Hangzhou city, China and examines the general, specific, and international aspects of the problems encountered in an international collaboration.
An integrated regionalization of earthquake, flood, and drought hazards in China
Authors: WANG JINFENG , WISE STEPHEN , HAINING ROBERT
Published: March 2007

Earthquake, flood, and drought data from different sources are combined in a single data set using the same data structure, projection, and scale. The intensity and frequency of each hazard is classified into severe, heavy, modest, and light, producing a classification with 64 combined states for the three kinds of hazard. These classes are then ranked according to severity. The three hazard coverages arc overlaid and the polygons that are produced are coded by the classification system. A map is produced that shows the distribution of these 64 classes in regions and their areas measured from the spatial topological data file in the GIS. Spatial analysis reveals the spatial association among the three hazards and between the three hazards and human factors. There is a brief discussion of the implications of the regionalized map for hazard monitoring.
Towards a framework for learning with GIS: The case of Urban World, a hypermap learning environment based on GIS
Authors: THOMPSON DEREK , LINDSAY FRANCIS E , DAVIS PAUL E , WONG DAVID W S
Published: March 2007

Off‐the‐shelf GIS toolboxes are inadequate for pedagogic purposes. Urban World, an Arc View application, attempts to address this shortcoming by including special features designed to foster student progress towards a better understanding of urban environments. This paper provides context for the Urban World system in an active, authentic learning environment for students of urban geography and planning at junior and senior levels in undergraduate curricula at universities in the United States. The paper describes the rationale for, and implementation of, several components of Urban World: a special graphid user interface; productivity tools for facilitating the acquisition of practical skills of mapping and spatial analysis; tools for accessing, undertaking, and submitting homework assignments in a paper‐less class; and various devices for assisting students to undertake spatial reasoning. GIS are Seen as an enabling technology for improving understanding by means of engaging students in empirical analysis. Spatial problem solvers and decision makers reach sound conclusions by employing reasoning skills applied to well‐formed databases; scientific research makcs progress with sound reasoning of many types. The effective teaching and learning about the geography of our world requires a strong foundation of spatid reasoning.
Conditional Properties of Hedge Funds: Evidence from Daily Returns*
Authors: Li Ying , Kazemi Hossein
Published: March 2007

Using daily returns on a set of hedge fund indices, we study (i) the properties of the indices' conditional density functions and (ii) the presence of asymmetries in conditional correlations between hedge fund indices and other investments and between hedge fund indices themselves. We use the SNP approach to obtain estimates of conditional densities of hedge fund returns and then proceed to examine their properties. In general, a nonparametric GARCH(1,1) model appears to provide the best fit for all strategies. We find that the conditional third and fourth moments are significantly affected by changes in the current volatility of returns on hedge fund indices. We examine changes in the conditional probability of tail events and report significant changes in the probability of extreme events when the conditioning information changes. These results have important implications for models of hedge fund risk that rely on probability of tail events. We formally test for the presence of asymmetries in conditional correlations to determine if there is contagion between hedge funds and other investments and between various hedge fund indices in extreme down markets versus extreme up markets. We generally do not find strong evidence in support of asymmetric correlations.
Hedge Fund Indices: Reconciling Investability and Representativity
Authors: Goltz Felix , Martellini Lionel , Vaissié Mathieu
Published: March 2007

Following a growing concern among investors about the quality of hedge fund index return data, this paper addresses the question of whether designing hedge fund indices that fulfil the usual requirements (in particular representative and investable) is or not a feasible task, given a variety of features that are specific to that industry. To test whether or not investability should necessarily come at the cost of representativity, we use a well‐known methodology in the asset pricing literature based on the concept of factor replicating portfolios. Our results suggest that it is actually possible to construct representative indices based on a limited number of funds that are open to new investments, except perhaps in the case of equity market neutral strategies, provided that: i) these funds are suitably selected and ii) a portfolio is constructed with the objective of replicating the common trend in hedge fund returns for a given strategy. A range of robustness tests are performed that show that high correlation of the factor replicating portfolios with the common factor of returns for each strategy is remarkably stable with respect to modifying the number of funds in the replicating portfolio or changing the frequency of rebalancing.
The Trickle‐down Effect: Ideology and the Development of Premium Water Networks in China’s Cities
Authors: BOLAND ALANA
Published: March 2007

This article examines the relationship between networked infrastructure and uneven development in transitional cities through a study of premium water networks in China. Beginning in the mid‐1990s, select buildings and housing enclaves began to bypass municipal tap water supply systems through the construction of small‐scale secondary pipe networks for purified drinking water. I focus on the early development of these premium water networks to highlight the ideological interplay between a new more market‐based approach to networked supply and the existing model characterized by relatively universal and uniform access within cities. I illustrate how this dual water supply model was well suited to the ideological conditions and contradictions associated with China’s economic liberalization in the 1990s. While the emergence of premium water networks can be linked to ascendant forms of market reasoning in the environmental and social spheres, I also argue that they were enabled by unresolved ideological tensions associated with China’s transitional program. Rather than providing a basis for resistance in the early development of premium water supply, the socialist legacy in urban water supply left its mark more in the noticeable absence of debate regarding the distributional outcomes. By examining premium water networks in relation to the politics of ideology in China’s transitional period, my analysis highlights the complex and sometimes unexpected ways that ideologies can influence the development of new infrastructural spaces and processes of splintering urbanism.
The Political Construction of the City‐Region: Notes from Sydney
Authors: McGUIRK PAULINE
Published: March 2007

City‐region theory — fuzzy as the boundaries of such a theory may be — centres on the claim that the territorial basis and organizational architecture of the global economy is now a mosaic of globally connected city‐regions rather than nations. Despite some intuitive appeal, there is a growing body of critique which targets specific frailties arising from the theoretical reliance in such arguments on a global capitalist‐logic and, relatedly, the focus on global exchange relations. In exploring the limits of these theoretical tendencies, this paper provides a critical account of the processual and practical formation of Sydney (NSW, Australia) as a city‐regional space of governance. It pays particular attention to the contingent emergence of Sydney’s metropolitan policy regionalism through political mediations of the particular and complex politics elicited by the spatial distributional consequences of city‐region development. Its concluding argument is that city‐region formation must be understood as an ongoing and multiscalar process without autonomy from the national political economy or from its territory.
Competitive behaviour and feeding rate in a reintroduced population of Griffon VulturesGyps fulvus
Authors: BOSÈ MICHELA , SARRAZIN FRANÇOIS
Published: March 2007

Intraspecific competitive behaviours were studied in a reintroduced population of Griffon VulturesGyps fulvusin order to describe the pattern of competition between ages and sexes, assess the effect of reintroduction on competitive behaviour, and study the potential consequences of food management on competition. There was no evidence for a difference in feeding or display rates between age classes. However interaction rates, aggressiveness and dominance were higher in old adults than in the other age classes. No difference in the pattern of competition was found between sexes. There was no difference in the competitive ability (feeding rate and dominance) of reintroduced and wild‐bred individuals. Feeding rates increased with resource availability. Group size also increased with food mass, but was lower than the theoretical maximum number of birds. This may be evidence of competition by interference where some individuals are able to increase their feeding rate by the exclusion of others. An increase in both the number of carcasses and the number of feeding sites is thus recommended to induce dispersal and reduce this competition.
Vascularization of small hepatocellular carcinomas: correlation with differentiation
Authors: Nakashima Y. , Nakashima O. , Hsia C. C. , Kojiro M. , Tabor E.
Published: March 2007

Abstract: Background: Hepatocellular carcinoma (HCC) is generally considered a hypervascular tumor when visualized by angiography. However, small HCCs are not always found to be hypervascular. Methods: To evaluate this, 50 HCCs ≤ 3 cm in diameter were studied. The 50 tumors consisted of 16 well‐differentiated HCCs, 25 moderately differentiated HCCs, and 9 that were each a mixture of well‐ and moderately differentiated HCC. Results: The mean number of portal tracts in the well‐differentiated HCCs was 34% of the number in the surrounding nontumorous liver, and few intratumoral arterioles were seen. In contrast, the mean number of portal tracts in the moderately differentiated HCCs was 0.6% of the number in the surrounding nontumorous liver, and abundant intratumoral arterioles were seen. For HCCs that contained both well‐differentiated and moderately differentiated tumor, the distribution of portal tracts and intratumoral arterioles in each portion was similar to that seen in well‐differentiated or moderately differentiated HCC alone, respectively. HCCs that were larger than 1.5 cm in diameter had fewer portal tracts and more intratumoral arterioles than HCCs whose diameters were ≤ 1.5 cm. Conclusions: As small HCCs increase in size and become increasingly dedifferentiated, the number of portal tracts apparently decreases and intratumoral arterioles develop. These findings may reflect changes in the hemodynamics as the HCC develops.
Co‐expression of Bcl‐2 protein and vascular endothelial growth factor in hepatocellular carcinomas treated by chemoembolization
Authors: Kobayashi Nao , Ishii Motoyasu , Ueno Yoshiyuki , Kisara Norihiro , Chida Nobuyuki , Iwasaki Takao , Toyota Takayoshi
Published: March 2007

Abstract: Aims/Background: Transcatheter arterial chemoembolization (TAE) of hepatocellular carcinoma (HCC) causes anoxia. Escape of cancer cells from anoxic injury may be enhanced by induction of proteins which provide resistance to apoptosis. Methods: We examined HCCs immuno‐histochemically for Bcl‐2, vascular endothelial growth factor (VEGF), p53, and Ki67. The staining intensity for VEGF, a protein induced by anoxia, was assessed morphometrically with a computer‐assisted image‐analyzer. Results: The frequency of Bcl‐2 positive cells was higher in HCCs that had undergone TAE (TAE HCC) than that in HCCs that had not undergone TAE (41.75 ± 15.06 vs. 1.01 ± 0.79 cells/1000 cells, p=0.0173). The frequency of p53‐ or Ki67‐positive cells was not increased after TAE. Of 12 TAE HCCs, 7 had Bcl‐2 positive HCC cells and 6 had clusters of Bcl‐2 positive cells. In contrast, 2 of 11 HCCs that had not undergone TAE had only a few, sporadically distributed, Bcl‐2‐positive cells. The staining intensity for VEGF was higher in Bcl‐2 positive than in Bcl‐2 negative areas (1.208 ± 0.091 vs. 1.071 ± 0.017, p=0.0222). Furthermore, the VEGF staining intensity in Bcl‐2 positive areas of TAE HCCs was higher than in Bcl‐2 negative areas (1.296 ± 0.126 vs. 1.066 ± 0.024, p= 0.0186), while in HCCs that had not undergone TAE the staining intensity was similar. Conclusions: TAE of HCC can induce Bcl‐2 expression, possibly through anoxic stress.
Cytoplasmic expression of hepatitis B core antigen in chronic hepatitis B virus infection: role of precore stop mutants
Authors: Park Young Nyun , Han Kwang Hyub , Kim Kyung Sup , Chung Jun Pyo , Kim Seungtaek , Park Chanil
Published: March 2007

Abstract: Aims/Background: The cytoplasmic expression of HBcAg is a possible target of immune hepatocytolysis and it is important for the pathogenesis of hepatic injury in chronic hepatitis B virus (HBV) infection. Cytoplasmic HBcAg expression has been suggested to be related to the precore sequence of HBV, HBV DNA level or cell cycle of hepatocytes and the aim of this study was to understand its mechanism. Material/Methods: We studied the expression pattern of HBcAg and its relationship to serum HBV DNA levels, cell proliferation activity of hepatocytes and precore mutation using 66 patients' sera and biopsied liver specimens of chronic hepatitis B. Results: The expression patterns of HBcAg were cytoplasmic predominant (CP) in 17 cases, nuclear and cytoplasmic (NC) in 10 cases and nuclear predominant (NP) in 9 cases and negative in 30 cases. CP expression cases showed a higher grade of hepatitis activity than NP expression cases. Serum HBV DNA levels showed a wide range and there was no significant difference according to the expression pattern of HBcAg. Cell proliferation activity of hepatocytes, measured by Ki‐67 (MIB‐1) labelling index was higher in CP expression cases than in NP expression cases and it was also significantly higher in cases of high grade than in low grade hepatitis activity. The precore region was evaluated by primer extension assay in 51 cases and there were 16 cases of 1896 precore mutant, 23 cases of wild type, 12 cases of mixed infection of 1896 precore mutant type and wild type. CP expression of HBcAg was significantly more frequent in 1896 precore mutant cases (86%) than in wild type cases (26%). Conclusion: CP expression of HBcAg is the major pattern of 1896 precore mutant cases and it might be involved in the severe liver injury of precore mutants. One of the mechanisms regulating CP HBcAg expression is suggested to be precore mutation of HBV as well as cell cycle of hepatocyte.
High, persistent hepatocellular proliferation and apoptosis precede hepatocarcinogenesis in growth hormone transgenic mice
Authors: Snibson Kenneth J. , Bhathal Prithi S. , Hardy Charles L. , Brandon Malcolm R. , Adams Timothy E.
Published: March 2007

Abstract: Aims/Background: Growth hormone (GH) transgenic mice are known to develop hepatocellular adenomas and carcinomas. In order to understand more about hepatocarcinogenesis in the GH‐transgenic mouse model we quantitated the rates of hepatocellular proliferation and apoptosis in these mice. Methods: Two lines of GH‐transgenic mice and non‐transgenic control mice were generated and sacrificed at regular intervals between one and nine months. Hepatocellular replication was measured by in vivo incorporation of bromodeoxyuridine (BrdU) and counting BrdU‐positive nuclei in histological liver sections. Serial sections taken from these mouse livers were also assessed for rates of hepatocellular apoptosis using the in situ endlabelling of fragmented DNA (TU‐NEL) method. Results: High levels of hepatocellular replication were sustained life‐long in this model. Increased rates of hepatocellular proliferation preceded the onset of hepatic inflammation, a prominent feature in the liver pathology of GH‐transgenic mice. In tumour tissue, cellular proliferation was up to 17‐fold greater than in surrounding non‐tumour tissue. Apoptosis rates were also elevated in non‐tumour regions of GH‐transgenic mouse livers compared to controls. Interestingly, large dysplastic hepatocytes were common in the fraction of cells undergoing apoptosis, especially in older mice with inflamed livers. The increase in the rate of hepatocellular apoptosis in GH‐transgenic animals largely balanced the augmented levels of proliferation seen in these mice. In tumour tissue, however, the profound increase in the number of proliferating tumour cells outstripped the increase in apoptosis. Conclusion: Relatively high and enduring levels of hepatocellular replication and apoptosis precede hepatocarcinogenesis in GH‐transgenic mice. Increased cellular proliferation and resistance to apoptosis were evident in tumour growth in older animals.
Interferon versus ribavirin plus interferon in chronic hepatitis C previously resistant to interferon: a randomized trial
Authors: Salmerón Javier , Ruiz‐Extremera Angela , Torres Cristina , Rodríguez‐Ramos Luis , Lavín Isabel , Quintero Dolores , Palacios Angel
Published: March 2007

Abstract: Background: More than 70% of patients with chronic hepatitis C are resistant to interferon therapy. Ribavirin, in association with interferon, has been demonstrated as effective, at a dose of 800–1200 mg/day, but the efficacy of a lower dose has not been established. Methods: We assessed the effectiveness of the combination of 600mg/day of ribavirin plus 3 MU of interferon over a period of 6 months, in a group of patients previously resistant to interferon. Sixty‐two patients with chronic hepatitis C with serum and hepatic HCV RNA relapsers or non‐responders to interferon, were randomly divided into two groups: group A received 3 MU of interferon alpha‐2b, three times a week for 6 months; group B was given the same dose plus 600 mg per day of ribavirin for 6 months. Two patients from each group dropped from therapy. One patient from group A and two from group B withdrew from treatment because of adverse effects. Results: Mean alanine aminotransferase levels were similar in both groups throughout the study. A sustained response was observed in 7% and 7.4% of groups A and B with short‐term response in 39% and 59%, and no response in 54% and 34% from both groups respectively (nonsignificant). At 12 months, 4 and 7 patients from groups A and B respectively, cleared serum HCV RNA however, only one sustained responder from each group cleared HCV RNA from peripheral blood mononuclear cells. At 18 months, 3 patients remained serum HCV RNA negative. Adverse effects were similar. Only haemoglobin values were lower in group B in the first month of therapy (p<0.05). Conclusion: In conclusion, the combination of 3 MU of interferon plus 600 mg of ribavirin is not effective in chronic hepatitis C resistant to interferon.
Frequent expression of mucin core protein MUC1 in non‐neoplastic gallbladder mucosa from patients with pancreaticobiliary maljunction
Authors: Yamato Taro , Kurumaya Hiroshi , Ohama Kazunori , Yamamichi Noboru , Watanabe You , Harada Kenichi , Sasaki Motoko , Nakanuma Yasuni
Published: March 2007

Abstract: Background: Gallbladder carcinoma is known to develop frequently in patients with pancreaticobiliary maljunction, though the causal relationship remains speculative. Methods: Histopathologic changes, expression of mucin core protein MUC1 and MUC2, and cell proliferative activities in the gallbladder mucosa from 27 patients with panceaticobiliary maljunction and 21 control gallbladders were examined. Three cases of pancreaticobiliary maljunction were associated with gallbladder carcinoma. Results: The lining epithelia of the non‐neoplastic gallbladder mucosa of pancreaticobiliary maljunction showed frequently papillary hyperplasia and higher proliferative activities, when compared to the control. In 3 cases with carcinoma, MUC1 was expressed on the luminal border and in the cytoplasm of carcinoma cells, particularly in de‐differentiated and invasive areas. MUC1 was variably expressed on the luminal surface of the lining epithelia of non‐neoplastic gallbladder mucosa in babies, children, youths and adults with pancreaticobiliary maljunction. However, such expression was focally seen in 2 of the 21 control cases (p<0.01). MUC2 was scattered in the hyperplastic and carcinomatous epithelial cells appearing as goblet cells in pancreaticobiliary maljunction and control groups. Conclusions: This study suggests that persistent MUC1 expression and increased cell proliferative activities of non‐neoplastic gallbladder epithelium of the patients with pancreaticobiliary maljunction after birth reflect an altered phenotype of epithelial cells and these abnormalities may be related to carcinogenesis in such patients.
HBeAg immunostaining of liver tissue in various stages of chronic hepatitis B
Authors: Lindh Magnus , Savage Kay , Rees Julia , Garwood Linda , Horal Peter , Norkrans Gunnar , Dhillon Amar P.
Published: March 2007

Abstract: Aims: We studied the tissue expression of hepatitis B e antigen (HBeAg) in 29 liver biopsies from 27 HBV carriers. Methods: HBeAg expression was assessed in relation to HBeAg in serum, precore mutations, HBV DNA levels and liver damage as measured by histology activity index. Results: HBeAg in liver tissue was detected by immunostaining in 6 of 7 patients positive for HBeAg in serum. In patients negative for HBeAg in serum, HBeAg was detected in none of 11 specimens from patients infected exclusively with a precore mutant that disrupts HBeAg synthesis, as compared with 3 of 11 specimens from patients carrying HBV with an intact precore region. These 3 patients all showed high HBV DNA levels in serum and severe liver damage. Conclusions: Overall, viral replication was strongly associated with the cytoplasmic HBeAg and nuclear HBeAg staining, but not with tissue staining for HBsAg. Because of the close relationship between tissue HBeAg expression and high viral load, the pathogenetic importance of HBeAg remains unclear.
Portal hypertension secondary to arterioportal fistulae: two unusual cases
Authors: Aithal G. P. , Alabdi B. J. , Rose J. D. G. , James O. F. W. , Hudson M.
Published: March 2007

Abstract: A 62‐year‐old male presented with variceal haemorrhage. Investigation demonstrated a fistula between the left gastric artery and portal vein with a porto‐systemic gradient of 35 mm Hg. Variceal bleeding was controlled by a transcatheter embolisation of the fistula, but the patient died of septicaemia three weeks later. The second patient, a 42‐year‐old male who presented with variceal bleeding was shown to have diffuse arterio‐venous fistulae involving the right lobe of the liver with a portosystemic gradient of 25 mm Hg. In this case the variceal bleeding was successfully controlled by insertion of a transjugular intrahepatic portosystemic shunt (TIPS). The pathogenesis of portal hypertension in arterioportal fistulae and the role of interventional radiological techniques in the management of variceal bleeding in these patients is discussed.
Hepatic expression of viral antigens, hepatocytic proliferative activity and histologic changes in liver biopsies of children with chronic hepatitis B after interferon‐α therapy
Authors: Özer Erdener , Özer Esra , Helvaci Mehmet , Yaprak Işin
Published: March 2007

Abstract: Aims/Background: The purpose of the present study was to evaluate the effects of interferon‐α (IFNα) treatment on necro‐inflammatory changes, viral antigen expression and hepatocytic proliferation rate assessed by Ki‐67 protein in liver biopsies of children with chronic hepatitis B virus (HBV) infection. Methods: The study included 18 children at prepubertal age. Histologic changes were assessed using a modified scoring system for grading of histological activity index and staging of fibrosis. The hepatocytic expression of Ki‐67 and HBV antigens including HBV surface antigen (HBsAg) and HBV core antigen (HBcAg) were evaluated using a semi‐quantitative immunohistochemical scoring system. Results: We found a significant decrease in the scores of intralobular confluent and spotty necrosis, periportal piecemeal necrosis, and in Ki‐67 immunopositivity after treatment. Serologic response with clearance of HBV e antigen in 9 patients (50%) was associated with this improvement. The extent of fibrosis and scoring of portal inflammation, however, did not show any difference. HBcAg expression showed a significant decrease after treatment, whereas HBsAg expression either increased or remained unchanged. Conclusion: We conclude that IFNα treatment might provide an improvement in hepatic histology with a reduction in hepatocytic injury. It might also provide a serologic response associated with a decrease in hepatocytic HBV replication.
Determination of serum hepatitis C virus (HCV) core protein using a novel approach for quantitative evaluation of HCV viraemia in anti‐HCV‐positive patients
Authors: Komatsu Fumio , Takasaki Kanae
Published: March 2007

Abstract: Aims/Background: Hepatitis C virus (HCV) infection is frequently diagnosed by detection of antibody to the HCV (anti‐HCV). Recently, a method for detection of HCV core protein, “Imucheck F‐HCV Ag Core Kokusai”, has been developed. In this study, we evaluate the utility of this method. Methods: HCV core protein levels in sera were determined using this following method; anti‐HCV titres were measured by particle agglutination (PA) test and then quantitative HCV‐RNA values were investigated using a competitive reverse transcription‐poly‐merase chain reaction (RT‐PCR) test. Results: The HCV core protein was detected only in anti‐HCV‐positive sera. Of 490 anti‐HCV‐positive sera, 130 (26.5%) were positive by this method. Of 144 anti‐HCV‐positive/HCV‐RNA‐positive sera, 130 (90.3%) were positive by it. A significant correlation between the HCV core protein levels and quantitative HCV‐RNA values was recognized (n=110, r=0.86, p<0.01). A significant correlation between the HCV core protein levels and alanine aminotransferase titres was also observed (n=67, r=0.72, p<0.05). All 71 patients with chronic active hepatitis, cirrhosis and hepatocellular carcinoma were positive with this method, whereas 18 of 32 patients with chronic inactive hepatitis were positive. Twenty‐three patients with chronic active hepatitis were treated with interferon‐α. During therapy, some patients showed a negative conversion of HCV core protein. One (7.7%) of 13 patients with HCV genotype 1 and 5 (62.8%) of 8 patients with genotype 2 remained negative for 6 months after the therapy. Conclusion: This method may be useful for quantitative evaluation of HCV viraemia in anti‐HCV‐positive patients.
Cerebral proton and phosphorus‐31 magnetic resonance spectroscopy in patients with subclinical hepatic encephalopathy
Authors: Taylor‐Robinson Simon D. , Buckley Camilla , Changani K. Kumar , Hodgson Humphrey J. F. , Bell Jimmy D.
Published: March 2007

Abstract: Background/Aims: In vivo magnetic resonance spectroscopy can be used to study cerebral metabolism non‐invasively. We aimed to correlate 1H and 31P magnetic resonance spectral abnormalities in the brains of patients with subclinical hepatic encephalopathy. Methods: Eighteen patients were studied at 1.5T, with combined 1H and 31P magnetic resonance spectra obtained from multiple voxels in the cerebral cortex and basal ganglia. Peak area ratios of choline, glutamine/glutamate, relative to creatine in the 1H spectra and percentage phosphomonoesters, phosphodiesters and βNTP signals relative to total 31P signals in the 31P spectra were measured. Results: Six patients did not complete the full examination –31P results are available from 12 patients only. Relative to creatine, there were reductions in choline and elevations in glutamine/glutamate, varying across the brain with choline significantly reduced in occipital cortex (p<0.05) and glutamine/glutamate most significantly elevated in temporo‐parietal cortex (p<0.0001). Percentage phosphomonoester (p<0.05), phosphodiester (p<0.05) and βNTP (p<0.005) signals were significantly decreased in basal ganglia spectra. No correlation was found between the magnitude of 1H and 31P MRS changes, except between percentage phosphodiester decrease and glutamine/glutamate to creatine increase in occipital cortex. Conclusion: The results of this study point to a multifactorial aetiology for this condition.
Fcγ receptor expression on hepatic macrophages and histological activity of chronic hepatitis
Authors: Matsumoto Seiji , Yamamoto Kazuhide , Nagano Takuya , Okamoto Ryoichi , Tagashira Masafumi , Ibuki Naohisa , Yabushita Kazuhfsa , Tsuji Takao
Published: March 2007

Abstract: Aims/Background: Activated liver macrophages in chronic hepatitis express a high affinity receptor for IgG named FcγRI. This study was performed to find the difference in FcγRI expression between chronic hepatitis B (CHB) and C (CHC) with reference to histological activity. Methods: Consecutive patients with CHB (20 cases) and CHC (25 cases) were enrolled in the study. Inflammatory activity was evaluated using the modified histological activity index (HAI). FcγRI‐positive macrophages were quantitatively measured by computer assisted morphometry. Results: Total HAI score was significantly higher in CHB than in CHC. Confluent necrosis was observed in significantly higher frequency in CHB at Stages 3–5 than in CHC. The percentage area of FcγRI‐positive macrophages was significantly higher in CHB than in CHC. In CHB, the percentage area of FcγRI‐positive macrophages correlated with total HAI (< 0.01) as well as the degree of confluent necrosis (< 0.01), interface hepatitis (< 0.05) and portal inflammation (< 0.05). FcγRI‐positive macrophages accumulated mainly at the site of confluent necrosis. In CHC, no correlation was observed between activated macrophages and any histological categories. Conclusion: These results suggest that FcγRI‐positive macrophages are associated with confluent necrosis in CHB, which is more common in CHB patients than in CHC.
Role of Th1 and Th2 cytokines in regulating the liver injury induced by delayed‐type hypersensitivity to picryl chloride
Authors: Xu Qiang , Cao Jingsong , Wu Feihua , Hayakawa Yoshihiro , Saiki Ikuo , Koda Akihide
Published: March 2007

Abstract: Aims/Background: We have previously reported that a new model of liver injury induced in mice by delayed‐type hypersensitivity (DTH) to picryl chloride (PCI) mimicks the pathogenesis of human hepatitis. This liver injury is mediated by CD4+ T cells. The interaction between lymphocyte function associated antigen 1 (LFA‐1) and intercellular adhesion molecule 1 (ICAM‐1) is an essential process for hepatocyte (HC) damage. The present study was undertaken to reveal the role of Th1 and Th2‐like cytokines in regulating the liver injury. Methods: The kinetics of cytokine production were examined by ELISA and RT‐PCR after the elicitation of liver injury for both serum protein and liver mRNA expression, respectively. A co‐culture assay between liver nonparenchymal cells (NPC) and HC was conducted to evaluate the cytokine regulation on the cell‐cell interaction. Expression of LFA‐1 on NPC and ICAM‐1 on HC were examined by FACScan and ELISA, respectively. Results: Serum IL‐2 and IFN‐γ showed a peak production at 6 and 12 h, while IL‐5 and IL‐4 reached their maximum levels at 18 and 24 h after induction of liver injury, respectively. Liver mRNA expression of IFN‐γ and IL‐4 had a similar time course to their corresponding products. Both recombinant murine IFN‐γ and IL‐2 triggered the hepatotoxicity of NPC or spleen cells at 0 h. In this case, an increased expression of both LFA‐1 on NPC and ICAM‐1 on HC was also observed. In contrast, IL‐4 and IL‐5 completely abolished the hepatotoxicity of NPC at 12 h without influencing the adhesion molecules. Conclusion: Th1 and Th2 may be involved in regulating liver injury. Th1/Th2 balance may critically contribute to the production of the liver injury or recovery from it.
Visualization of oxygen radical production in mouse liver in response to infection with Schistosoma mansoni
Authors: Abdallahi Ould M. S. , Hanna Stéphane , De Reggi Max , Gharib Bouchra
Published: March 2007

Abstract: Background/Aims: The tropical parasite S. mansoni induces granulomatous inflammation in the liver, following the lodging of eggs in this organ. In vitro studies suggested that the host's response might involve the production of oxygen radicals. Methods: In an attempt to investigate the situation at the site of inflammation, under disease conditions, livers of infected mice were treated with dichlorodihydrofluorescein diacetate which fluoresces after oxidation. Results: Fluorescence of the oxidized tracer revealed that oxygen radicals were produced by granulomatous inflammatory cells. The phenomenon reached its highest intensity close to the eggs. The membranes of the cells were strongly labelled, probably reflecting membrane‐associated NADPH oxidase activity. The cytoplasm of hepatocytes was also fluorescent but with lower intensity; hepatocyte membranes or nuclei were not labelled. Fluorescence was reduced drastically by treatment with catalase and antioxidants, indicating the occurrence of H2O2. Treatment with superoxide dismutase had no effect. Neither the livers of uninfected animals nor those of infected animals before parasite egg deposition were labelled. Eosinophil peroxidase activity was released in the areas of inflammatory cells, but was not found in hepatocytes. Conclusions: The H2O2/peroxidase system, which is the cornerstone of the antimicrobial defense associated with inflammation, is activated in close contact with parasite eggs. The process does contribute to egg killing in vivo. Moreover, hepatocytes undergo oxidative stress in the entire organ. This finding is in agreement with the parasite‐induced decrease of liver antioxidant defenses demonstrated previously.
Incidence of Motion Loss of the Stifle Joint in Dogs with Naturally Occurring Cranial Cruciate Ligament Rupture Surgically Treated with Tibial Plateau Leveling Osteotomy: Longitudinal Clinical Study of 412 Cases
Authors: JANDI AVTAR S. , SCHULMAN ALAN J.
Published: March 2007

Objective— To report the incidence of loss of stifle extension or flexion and its relationship with clinical lameness after tibial plateau leveling osteotomy (TPLO) for treatment of cranial cruciate ligament (CCL) rupture.

Study Design— Longitudinal study.

Animals— Dogs (n=280) with CCL rupture (n=412).

Methods— TPLO was performed without meniscal release or arthrotomy. Angles of extension and flexion of the stifle were measured by goniometry to determine range of motion. Based upon motion loss, stifles were divided in 3 groups: no loss of extension or flexion (n=322), <10° loss of extension or flexion (n=78), ≥10° loss of extension or flexion (n=12).

Results— Loss of extension or flexion ≥10° was associated with significantly (P=.001) higher clinical lameness scores in comparison with no loss, or loss of extension or flexion <10°. Osteoarthrosis in the cranial femorotibial joint was significantly correlated (P<.005, r2=0.55) with loss of extension. Loss of extension ≥10° was less tolerable and less amenable to physical rehabilitation than flexion loss.

Conclusions— Loss of extension or flexion ≥10° was responsible for higher clinical lameness scores. Osteoarthrosis in the cranial femorotibial joint led to extension loss.

Clinical Relevance— Loss of extension or flexion should be assessed in dogs with persistent clinical lameness after TPLO so that early intervention can occur. Our study provides guidelines to define clinically relevant loss of extension or flexion of stifle joint after TPLO.
Recombinant Human Bone Morphogenetic Protein‐2 in Absorbable Collagen Sponge Enhances Bone Healing of Tibial Osteotomies in Dogs
Authors: FARIA MARIA L. E. , LU YAN , HEANEY KATHLEEN , UTHAMANTHIL RAJESH K. , MUIR PETER , MARKEL MARK D.
Published: March 2007

Objective—To compare the efficacy of 2 doses of recombinant human bone morphogenetic protein‐2 (rhBMP‐2) on tibial osteotomy healing in dogs.

Study Design—Experimental, randomized complete block (n=7).

Animals—Adult female dogs (n=21).

Methods—Right midshaft tibial osteotomies were created and stabilized with a 1‐mm gap using type I external fixators. Seven dogs were untreated controls and 14 with osteotomies were treated with either 0.05 or 0.2 mg/mL rhBMP‐2 delivered in an absorbable collagen sponge (ACS). At 8 weeks, dogs were euthanatized and bones were mechanically tested and examined by microscopy.

Results—Bone healing based on radiographic scoring, was significantly improved in dogs treated with 0.2 mg/mL of rhBMP‐2 compared with the other groups; these tibiae were also significantly stronger and stiffer than 0.05 mg/mL rhBMP‐2 and control osteotomized tibiae. Histologic scores were significantly better for 0.2 mg/mL rhBMP‐2 group than 0.05 mg/mL rhBMP‐2 group, but neither was significantly different from control.

Conclusions—rhBMP‐2 in ACS at a concentration of 0.2 mg/mL improves healing of tibial osteotomies in dogs compared with untreated controls and 0.05 mg/mL rhBMP‐2 based on force plate analysis and radiographic evaluation. This was not confirmed histologically but treated bones had improved mechanical properties at 8 weeks.

Clinical Relevance—After a long bone fracture, dogs may face a long recovery period before full return of limb function. rhBMP‐2, in association with good fracture fixation principles, may enhance bone healing in dogs with diaphyseal fractures.
Clinical Application of Recombinant Human Bone Morphogenetic Protein‐2 in 4 Dogs
Authors: MILOVANCEV MILAN , MUIR PETER , MANLEY PAUL A. , SEEHERMAN HOWARD J. , SCHAEFER SUSAN
Published: March 2007

Objective— To describe outcome in dogs with insufficient bone healing treated with recombinant human bone morphogenetic protein‐2 (rhBMP‐2).

Study Design— Retrospective study.

Animals— Four dogs clinically affected with delayed union or nonunion bone healing.

Methods— Medical records were reviewed for signalment, clinical problem, treatment, and outcome.

Results— Four dogs that had delayed‐ or nonunion of bone fracture, osteotomy, or arthrodesis were treated with either minimally invasive, fluoroscopically guided, percutaneous administration or direct surgical application of rhBMP‐2. Doses used ranged from 0.2 to 1.6 mg of rhBMP‐2. In 3 dogs, a calcium phosphate matrix (CPM) carrier was used whereas in 1 dog commercially prepared rhBMP‐2 impregnated in an absorbable collagen sponge (INFUSE® Bone Graft) was used. This latter dog had osteomyelitis associated with implant infection before rhBMP‐2 administration. Rapid radiographic union was noted in all dogs with excellent long‐term outcome. Adverse effects were minimal and included transient worsening of lameness after percutaneous administration of rhBMP‐2 in 2 dogs.

Conclusions— rhBMP‐2 stimulated rapid bone formation at delayed‐ or nonunion sites resulting in radiographic bone union with minimal adverse effects and excellent long‐term outcome in 4 dogs.

Clinical Relevance— Direct intraoperative administration or fluoroscopically guided, minimally invasive delivery of rhBMP‐2 may be an effective treatment modality for bone delayed‐ or nonunions and could potentially be used to stimulate new bone production in a variety of orthopedic surgical conditions in dogs.
In Vitro Comparison of Tibial Plateau Leveling Osteotomy with and Without Use of a Tibial Plateau Leveling Jig
Authors: SCHMERBACH KAY INGO , BOELTZIG CHRISTIAN KONRAD MATTHIAS , REIF ULLRICH , WIESER JAN CARSTEN , KELLER THOMAS , GREVEL VERA
Published: March 2007

Objective— To evaluate the influence of a tibial plateau leveling jig on osteotomy orientation, fragment reduction, and postoperative tibial plateau angle (TPA) during tibial plateau leveling osteotomy (TPLO).

Study Design— In vitro experimental study.

Animals— Large‐breed canine cadavers (n=20).

Methods— TPLO was performed on 40 hindlimbs using 4 methods. Group 1: Jig; dogs in dorsal recumbency with the osteotomy parallel to the distal jig pin. Groups 2–4: No jig; dogs in lateral recumbency with the osteotomy in a vertical orientation (group 2: tibia parallel to the table top; group 3: controlled superimposition of the femoral condyles; group 4: internal rotation of the tibia). Postoperative TPA, fragment reduction, and osteotomy orientation relative to the tibial plateau were compared. Positive or negative values denoted deviation from parallel relative to the tibial plateau.

Results— Postoperative TPA, fragment reduction, and proximodistal osteotomy orientation were not significantly different between groups. Craniocaudal osteotomy orientation was significantly different (P<.005) from the tibial plateau. Median deviations were −4.0° (group 1), 11.8° (group 2), 11.2° (group 3), and 0.2° (group 4). Group 1 was not significantly different from group 4.

Conclusions— A jig is not essential for osteotomy orientation, tibial plateau rotation, or fragment reduction. Comparable results were achieved performing a vertical osteotomy with the tibia slightly internally rotated (10°–15°) and parallel to the table surface.

Clinical Relevance— TPLO without use of a jig reduces surgical trauma, is less time consuming, and reduces cost.
Clinical Evaluation of a Titanium, Headless Variable‐Pitched Tapered Cannulated Compression Screw for Repair of Frontal Plane Slab Fractures of the Third Carpal Bone in Thoroughbred Racehorses
Authors: HIRSCH JONATHAN E. , GALUPPO LARRY D. , GRAHAM LINDSAY E. , SIMPSON EDWIN L. , FERRARO GREGORY L.
Published: March 2007

Objective— To report clinical evaluation of third carpal bone (C3) frontal plane slab fracture repair with the Acutrak® screw system.

Study Design— Prospective case series.

Sample Population— Racing Thoroughbreds (n=17) with frontal C3 slab fractures.

Methods— C3 slab fractures in Thoroughbred racehorses (1999–2004) were repaired by use of the Acutrak® screw system. Data collected were (1) preoperative variables—gender, age at injury, limb involved, injury occurrence, fracture thickness, complexity, and displacement, race starts and earnings and (2) postoperative variables were: surgical complications, days to first start, race starts, and earnings. A Wilcoxon signed‐rank test was used to compare pre‐ and postoperative starts and earnings; significance was set at P<.05.

Results— Seventeen Thoroughbred racehorses (12 females, 3 males, 2 geldings) were enrolled. Mean (±SD) age at injury was 3.3±1.0 years. Right carpi (10) were affected more than left (7). Ten injuries occurred during training, 7 during racing. Twelve of 15 horses that raced before injury returned to racing. Average days to first start was 349.3±153.9 days. Horses that returned to racing had more starts after repair (median, 6.5 versus 3.5; P=.04) and did not have decreased earnings per start (median, $2452 versus $3061; P=.30).

Conclusion— The Acutrak® screw system is a useful repair technique for frontal C3 slab fractures in Thoroughbred racehorses.

Clinical Relevance— Adequate reduction and stability of C3 slab fractures can be achieved with the Acutrak® screw system, decreasing the likelihood of fragment splitting and screw head impingement on carpal soft tissues.
In vitro quality of red blood cells (RBCs) collected by multicomponent apheresis compared to manually collected RBCs during 49 days of storage
Authors: Picker Susanne M. , Radojska Stela M. , Gathof Birgit S.
Published: March 2007

BACKGROUND: New technologic developments enable automated collection and preparation of red blood cells (RBCs). This study's aim was to evaluate quality of apheresis‐derived RBCs (ARBCs) collected as single units along with platelets (RBC‐Ps) or double units (2‐RBCs) with four different apheresis systems.

STUDY DESIGN AND METHODS: Sixty‐six donors with similar baseline variables underwent RBC apheresis collection with various machines (Amicus [15 RBC‐Ps] and Alyx [15 2‐RBCs], Baxter; the Trima Accel [9 RBC‐Ps, 8 2‐RBCs], Gambro, and the MCS+[9 RBC‐Ps, 10 2‐RBCs], Haemonetics Corp.). In vitro properties were analyzed during 49 days of storage and compared to manual RBCs (MRBCs, n = 14).

RESULTS: All units but one, Alyx, demonstrated white blood cell counts of less than 1 × 106. ARBCs showed lower variability in volume compared to MRBCs. All units met international requirements (European, AABB) for hematocrit (50%‐70%), hemoglobin (>40 g/unit), and RBC mass (≥153 mL). pH values remained similar between study groups without reaching critical limits in any unit. MRBCs had slight advantages for hemolysis at the end of storage and were significantly superior in energy maintenance as indicated by less ATP degradation and potassium leak most likely due to more pronounced anoxidative glycolysis particularly during the first half of storage. Owing to more declining oxidative glucose metabolism, ARBCs demonstrated higher methemoglobin formation and subsequent oxygen release until the end of storage.

CONCLUSION: ARBCs exhibited better predictability in volume and absolute RBC mass than MRBCs and demonstrated sufficient in vitro quality throughout storage, even though lower ATP preservation and higher methemoglobin formation were observed compared to MRBCs probably due to differences in glucose metabolism.