bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of foliar sprays containing calcium, magnesium and titanium on peach (Prunus persica L) fruit quality
Authors: Alcaraz‐López Carlos , Botía María , Alcaraz Carlos F , Riquelme Fernando
Published: May 2004

Sprays containing Ca2+, Mg2+ or Ti4+ were applied to peach trees in several combinations. Effects of treatments on the commercial quality of fruits, especially focused on improving their mechanical properties, are discussed. All treatments containing titanium increased tree performance (branch elongation, flowering and fruit set intensities) and fruit size. At harvest, fruits from Ti‐treated trees showed improved resistance to compression and penetration, as well as a decrease in weight loss during postharvest storage. A similar response was obtained for external colour, though all treatments seemed to delay somewhat the apparent ripening status. Nevertheless, fruits from Ti‐treated trees showed better behaviour in the evolution of colour parameters during storage than did control fruits. Titanium application showed significant increases in iron, copper and zinc concentrations in the peel and calcium concentration in the peel and flesh. This improvement in calcium absorption is explained as a consequence of the beneficial effect of titanium on the absorption, translocation and assimilation processes. Copyright © 2004 Society of Chemical Industry
Chemometrics can be applied to mechanical testing data to characterise stem toughness and stiffness in crop plants
Authors: Kemsley EK , Swinhoe RR , Smith AC , McCann MC , Wang TL
Published: May 2004

Mechanical tests have been used to assess the engineering properties of pea (Pisum sativum L) stems. Measurements were made on plants of three different genotypes at four different stages of development and at five defined locations along the stem. The force–displacement curves obtained were used to estimate values of the engineering properties of toughness and flexural modulus, from cutting and flexure mechanical tests respectively. Specimens of all genotypes showed an increase in toughness with age and generally also with stem height. However, there were marked differences in flexural modulus between genotypes. One genotype, known to exhibit a ‘stiff straw’ characteristic, showed a consistent increase in modulus with age and stem height, and at and beyond fruiting had substantially the greatest flexural modulus. The remaining genotypes showed decreasing flexural modulus with age. Chemometric methods were used to analyse sets of complete force–displacement curves, following suitable pre‐processing to allow the application of linear algebra methods. Whereas univariate consideration of the engineering quantities allowed trends to be observed, multivariate analysis of force–distance curves was able to model empirically the genotype differences so that individual specimens could be largely correctly classified. Examination of some of the model coefficients suggested that the ability to discriminate between genotypes is related to structural features of the specimens and that cutting tests in particular are sensitive to the anatomy of the specimen. This is the first time that chemometric methods have been applied to such data and suggests the potential of mechanical tests combined with multivariate analysis to form the basis of a screening system for phenotypic properties of new lines and varieties. Copyright © 2004 Society of Chemical Industry
Effect of variety and crude protein content on nutrients and certain antinutrients in field peas (Pisum sativum)
Authors: Wang Ning , Daun James K
Published: May 2004

Protein content was used as an indicator of environmental conditions for a study on varietal and environmental variation in proximate composition, minerals, amino acids and certain antinutrients of field peas. Four field pea varieties, each with three levels of protein content, were selected. Crude protein content overall ranged from 20.2 to 26.7%. Analysis of variance showed that both variety and environmental conditions had a significant effect on starch, acid detergent fibre (ADF), neutral detergent fibre (NDF) and fat content, but ash content was only affected by variety. Significant varietal and environmental differences in potassium (K), manganese (Mn) and phosphorus (P) were noted. Calcium (Ca) and copper (Cu) showed significant varietal differences, while iron (Fe), magnesium (Mg) and zinc (Zn) had significant environmental differences. Environmental conditions showed significant effects on alanine, glycine, isoleucine, lysine and threonine content. Variety had a significant effect on sucrose, raffinose and phytic acid content, whereas environmental conditions had an influence on trypsin inhibitor activity (TIA). The major pea components protein and starch were inversely correlated. ADF, NDF, Fe, Mg, Zn and the amino acid arginine were positively correlated with protein content. The amino acids glycine, histidine, isoleucine, lysine and threonine were negatively correlated with protein content. It was found that tryptophan was the most deficient amino acid and the sulphur‐containing amino acids were the second limiting amino acids in peas. Raffinose was positively correlated with sucrose but negatively correlated with verbascose. There were significant correlations between mineral contents and some of the proximate components. Copyright © 2004 Society of Chemical Industry
Effect of applying formic acid, heterolactic bacteria or homolactic and heterolactic bacteria on the fermentation of bi‐crops of peas and wheat
Authors: Adesogan Adegbola T , Salawu Mustapha B
Published: May 2004

This work aimed to compare the effectiveness of bacterial inoculants or a chemical additive for preserving whole‐crop silages made from wheat, two pea varieties (cv Magnus or Setchey) or intercrops of wheat and both pea varieties. The forages were harvested when the wheat and peas were at the late milk and yellow wrinkled stages respectively, and conserved in five replicate mini silos without treatment (control) or after treatment with 2.5 g kg−1 of formic acid (FA) or 1 × 106 cfu g−1 fresh forage of either of two bacterial inoculants (WholeCrop Gold (WCG) or WholeCrop Legume (WCL), Biotal Ltd, Cardiff, UK). WCG contained Lactobacillus buchneri, while WCL contained L buchneri, L plantarum and Pediococcus pentosaceus. Chemical composition, fermentation characteristics and in vitro digestibility were measured after 65 days of ensiling. Additive‐treated bi‐crops had lower (P < 0.05) concentrations of soluble N, ammonia N and lactic acid than the controls. Inoculant‐treated bi‐crops had higher (P < 0.001) acetic acid and lower (P < 0.001) residual water‐soluble carbohydrate (WSC) concentrations than FA‐treated bi‐crops. WCL‐treated bi‐crops had similar residual WSC concentrations to and higher (P < 0.05) starch concentrations than WCG‐treated bi‐crops. Unlike Magnus pea bi‐crops, Setchey pea bi‐crops treated with WCL had lower concentrations of ammonia N (P < 0.01) and acetic acid (P < 0.001) and higher concentrations of starch (P < 0.001) and lactic acid (P < 0.05) than those treated with WCG. For both bi‐crops, FA‐treated bi‐crops were more stable (P < 0.05) than inoculant‐treated or untreated silages, and the stability of inoculant‐treated and untreated silages was similar. Formic acid treatment was also the most effective at reducing WSC losses in the bi‐crop and pea silages. Inoculant treatment reduced proteolysis in these forages but did not prevent spoilage in the bi‐crops. Additive treatment reduced yeast counts but did not improve the fermentation in wheat silages. Copyright © 2004 Society of Chemical Industry
Nutrient utilisation in response to dietary supplementation of chicory inulin in growing pigs
Authors: Rideout Todd C , Fan Ming Z
Published: May 2004

The digestive and post‐absorptive utilisation of dietary crude protein (CP), calcium (Ca) and phosphorus (P) in response to dietary supplementation of chicory inulin extract was investigated with six Yorkshire barrows with an average initial body weight of 30 kg. The barrows were fed a corn (maize) and soybean meal‐based diet containing 0 or 50 g kg−1 chicory inulin extract according to a two‐period crossover design. The digestive utilisation of CP, Ca and P did not differ (P > 0.05) between the control and the inulin‐fed pigs. Furthermore, the post‐absorptive urinary loss of CP and Ca was not affected (P > 0.05) by 50 g kg−1 chicory inulin supplementation. However, inulin supplementation improved post‐absorptive P utilisation through a reduction (P = 0.01) in urinary P loss by 1.6 percentage units compared with the control group. In conclusion, dietary supplementation of 50 g kg−1 chicory inulin does not affect dietary CP and Ca utilisation but does reduce urinary P loss in growing pigs. Copyright © 2004 Society of Chemical Industry
The significance of critical processing steps in the production of dried egg albumen powder on gel textural and foaming properties
Authors: Hammershøj Marianne , Peters Lars V , Andersen Henrik J
Published: May 2004

The purpose of the present work was to study the variation in egg albumen functional properties as a function of seven selected processing steps from the initially raw liquid albumen to the final dried egg albumen powder. Albumen samples in six replicates were analysed for dry matter, pH, glucose, triglycerides, albumen gel properties (ie textural stress and Hencky strain, water‐ and protein‐binding capacity and gel colour L*, a*, b*), foaming properties (ie overrun, stability against drainage and bubble breakdown) and surface tension. The gel texture and water‐holding capacity significantly decreased during the processing steps from raw albumen through storage, centrifugation and ion exchange, whereas the final dry‐pasteurisation resulted in increased gel properties. Covalently linked protein polymers formed during the dry‐pasteurisation, as revealed by SDS‐PAGE, may explain this improvement. The foam overrun increased twofold during the three final steps of ultrafiltration, spray‐drying and dry‐pasteurisation compared with the raw albumen; however, the foam stability decreased, ie drainage and foam volume breakdown rates increased. The surface pressure increase was positively correlated with the foam overrun. This paper reveals at which processing steps the control of functional properties of egg albumen powder can take place. Copyright © 2004 Society of Chemical Industry
Influence of the stage of ripeness of plantains and some cooking bananas on the sensory and physicochemical characteristics of processed products
Authors: Yomeni MO , Njoukam J , Tchango Tchango J
Published: May 2004

The influence of the stage of ripening of the fruit of cultivars of plantain (French Sombre) and some cooking bananas (Dwarf Kalapua and Bluggoe) on the sensory and physico‐chemical characteristics of processed products was evaluated. Chips made from these cultivars at corresponding stages of ripeness had water contents less than 20 g kg−1 for fruits at stages 1 and 3 and less than 60 g kg−1 for those at stages 4 and 5. There was no significant difference (p > 0.05) between the ash contents of chips at different stages of ripeness for all the cultivars. Protein contents increased with increasing ripeness for all the cultivars; the fat contents decreased with increasing ripeness and varied from one cultivar to another. The available food energy was more than 4840 kcal kg−1 of chips for all the cultivars at all stages of ripeness. The best chips were obtained from fruits at stages 1 and 3. Flours obtained from the fruits of these cultivars at different stages of ripeness had water contents lower than 60 g kg−1. The fat, ash and protein contents were low, while the carbohydrate contents were high. For all the cultivars the yields of chips and flour were higher for the plantain cultivar (French Sombre) than for the cooking banana cultivars, irrespective of the stage of ripeness of the fruits. Cakes made from the different flours had good nutritional quality. The cakes and chips submitted for sensory evaluation were all accepted by consumers, although to differing extents. Fruits at stages 1 and 3 of ripeness which presented fewer problems during drying were the most suitable for the manufacture of flour for making cakes. Copyright © 2004 Society of Chemical Industry
Cytotoxic T-cell elimination during anti-CD4-induced rat liver acceptance and rapid replacement of functional graft antigen-presenting cells
Authors: Usui Kazuhiro , Yamaguchi Junzo , Gu Weili , Kanematsu Takashi
Published: May 2004

In previous studies, we showed that primed T cells were eliminated in long-term survival Wistar Furth (WF) recipient rats with spontaneously accepted Lewis (LEW) liver graft and that the grafted liver lost the ability to elicit rejection reaction early after liver transplantation. We hypothesized that the same phenomenon may be observed in tolerant animals after immunosuppression in a rejector rat strain combination (WF→LEW). Furthermore, we proposed the repopulation of liver allograft with host antigen-presenting cells rapidly after transplantation. Recipient LEW rats that underwent anti-CD4 therapy accepted the WF liver allografts after a transient rejection reaction. In tolerant animals, alloreactive CD8 T cell precursors were present, but primed T cells were absent. Intraperitoneal challenge with grafted WF liver homogenates obtained from recipient LEW rats on day 4 after transplantation did not induce transient rejection responses in long-term survival recipient LEW rats, a finding that differed from the results of experiments using normal WF liver homogenates. However, challenge with grafted WF liver homogenates, similar to those of normal LEW liver homogenates, induced rejection responses in long-term survival recipient WF rats with LEW liver allograft. Flow cytometric analysis confirmed that most of nonparenchymal cells in the grafted WF liver were recipient (LEW) genotype. These observations showed that the deletional mechanism of effector T cells also is observed in this setting, and professional donor antigen-presenting cells are replaced by those of recipient genotype within the graft during the early phase of transplantation. (Liver Transpl 2004;10:734-742.)
Heme oxygenase-1 potentiates the survival of small-for-size liver graft
Authors: Yang Zhen Fan , Tsui Tung Yu , Ho David W. , Tang Terence C. , Fan Sheung-Tat
Published: May 2004

This study aims to clarify the role of heme oxygenase-1 (HO-1) in small-for-size liver transplantation. Transplantation was performed using 40% small-for-size or 100% whole liver grafts in rats. When no treatment was given, over-expression of HO-1 was detected predominantly in the small-for-size grafts at 6 hours after reperfusion as compared to whole grafts in both syngeneic and allogeneic combinations. Recombinant adenoviral vector encoding HO-1 gene (AdHO-1) administered to donors 48 hours before transplantation enhanced HO-1 expression in both whole and small-for-size allografts, with a predominant augmentation in the small-for-size allografts, suggesting favorable conditions for the induction of HO-1 expression in small-for-size allografts. In close relation to the expression level of HO-1, AdHO-1 significantly prolonged both whole and small-for size allograft survivals, with a remarkable effect in the small-for-size allograft group. The prolongation of allograft survival was blocked by the HO-1 inhibitor (zinc protoprophyrin IX). The non-treated small-for-size allografts demonstrated impaired liver function during the early period after reperfusion, which could be improved by over-expression of HO-1, but reversed by the HO-1 inhibitor. The markedly increase expression HO-1 in small-for-size allografts was associated with lower levels of adhesion molecules and pro-inflammatory cytokines in the early phase after reperfusion. These findings support the beneficial effects of HO-1 on allograft survival. In conclusion, the ability of small-for-size grafts in the induction of HO-1 expression might facilitate their own survival in liver transplantation. (Liver Transpl 2004;10:784-793.)
Interleukin-2 receptor antibody (basiliximab) for immunosuppressive induction therapy after liver transplantation: A protocol with early elimination of steroids and reduction of tacrolimus dosage
Authors: Liu Chi Leung , Fan Sheung Tat , Lo Chung Mau , Chan See Ching , Ng Irene O. , Lai Ching Lung , Wong John
Published: May 2004

A prospective evaluation was performed to study the potential benefits of the use of interleukin-2 receptor antibody (IL-2Rab) in the induction therapy with early elimination of steroid and reduction of tacrolimus dosage in liver transplant recipients among whom 94% had chronic hepatitis B infection. Thirty-one liver transplant recipients who underwent right-lobe live donor (n = 19) or cadaveric (n = 12) liver transplantation received IL-2Rab, basiliximab 20 mg intravenously within 6 hours of graft reperfusion and on postoperative day 4 (IL-2ab group). Two doses of steroid injection were given intraoperatively and on postoperative day 1. Postoperative immunosuppression was maintained with oral tacrolimus and mycophenolate mofetil without the use of steroids. The operative outcomes were compared with those of 49 patients who received standard immunosuppressive regimen consisting of tacrolimus and corticosteroid (steroid group). The overall postoperative morbidity and hospital stay were comparable between the 2 groups. There were significantly lower incidences of postoperative new-onset diabetes (0% vs 28%, P = .011), acute cellular rejection (6% vs 27%, P = .038), and cytomegalovirus (CMV) antigenemia (0% vs 18%, P = .011) in the IL-2Rab group compared with the steroid group. The blood cholesterol level at 6 months after transplantation was significantly lower in the IL-2Rab group (median, 4.0 vs 4.4 mmol/L, P = .007). On follow-up, none of the patients in the IL-2Rab group had hepatitis B viral breakthrough or hepatocellular carcinoma (HCC) recurrence, whereas 1 and 3 patients in the steroid group developed these complications, respectively. In conclusion, treatment of liver transplant recipients with IL-2Rab with early withdrawal of steroids and reduction of tacrolimus dosage is associated with lower incidences of postoperative new-onset diabetes, acute cellular rejection, and CMV antigenemia, as well as a lower serum cholesterol level. Further studies and long-term follow-up are required to document their potential benefits on hepatitis B and HCC recurrences. (Liver Transpl 2004;10:728-733.)
Enhanced proliferation of hepatic progenitor cells in rats after portal branch occlusion
Authors: Ise Norihito , Sato Tsutomu , Yasui Ouki , Watanabe Go , Koyama Kenji , Terada Kunihiko , Sugiyama Toshihiro , Yamamoto Yuzo
Published: May 2004

It is known that hepatic progenitor cells increase in number after liver injury caused by carcinogens, but this injury cannot be reproduced in humans. In order to create a practical source of hepatic progenitor cells, changes in the number of liver epithelial cells (LECs), a type of hepatic progenitor cell, were examined following partial interruption of the portal flow. Efficiency in this isolation procedure was investigated, and isolated LECs were transplanted into livers to demonstrate their differentiation into hepatocytes in vivo.A volume of 70% of Sprague-Dawley rat’s livers was exposed to portal vein ligation. LECs, identified as alpha-fetoprotein (AFP)-positive and albumin-negative cells, were counted and LECs isolated from the portal vein ligated-lobe were characterized by immunostaining and Western blotting. Isolated cells were subjected to a 1-week-culture, and the number of colonies formed on dishes was counted. The cells were then transplanted to the livers of genetic analbuminemic rats and identified by immunohistochemistry. The number of LECs in the portal ligated-lobes on day 7 was 14.7 ± 6.5 cells/1,000 hepatocytes: 18 times higher than numbers in a normal liver. A significant increase was noted from day 3 until day 28. Isolated LECs were AFP-positive, albumin-negative, and cytokeratin-19-positive cells. The number of colonies on the 7th day following portal vein ligation was 42 times higher than in a normal liver. After transplantation of the LECs to the analbuminemic rat, a cluster of albumin-producing cells was present until day 56, suggesting that they differentiate into hepatocytes. We conclude that after portal vein occlusion, the liver can be a good source of hepatic progenitor cell. These results open up the possibility of cellular transplantation for liver functional support in clinical settings. (Liver Transpl 2004;10:748-754.)
Pringle’s maneuver and selective inflow occlusion in living donor liver hepatectomy
Authors: Imamura Hiroshi , Kokudo Norihiko , Sugawara Yasuhiko , Sano Keiji , Kaneko Jun-ichi , Takayama Tadatoshi , Makuuchi Masatoshi
Published: May 2004

While inflow occlusion techniques such as Pringle’s maneuver are accepted methods of reducing bleeding without inducing liver injury during liver surgery, donor hepatectomy for living donor liver transplantation is currently performed without inflow occlusion for fear that injury to the graft may result. We have performed donor hepatectomy for 12 years using selective intermittent inflow occlusion, a technique in which the portion used to form the graft is perfused during hepatectomy. Starting in November 2000, we applied intermittent Pringle’s maneuver to donor hepatectomy in 81 cases of living donor liver transplantation. We reviewed our experience with Pringle’s maneuver and selective inflow occlusion techniques in donor hepatectomy in living donor liver transplantation. The quality of the grafts was assessed and compared by determining maximum postoperative aspartate aminotransferase (AST) and alanine aminotransferase (ALT) values. Neither primary nonfunction nor dysfunction occurred. Maximum AST values in the recipients were the same whether the liver segments that formed the grafts were totally ischemic during dissection (total ischemia), partially ischemic (partial ischemia), perfused only with arterial blood flow (portal ischemia), or not ischemic at all (no ischemia). Maximum ALT values in the recipients of the total ischemia group was lower, albeit not significantly, than in other groups. Total inflow occlusion can be applied to living donor hepatectomy without causing graft injury. In conclusion, because the transection surface is blood-free, there is decreased risk to the donor during living donor liver transplantation surgery, and surgeons should not hesitate to apply this technique because it contributes to donor safety. (Liver Transpl 2004;10:771-778.)
End-to-side portocaval shunting for a small-for-size graft in living donor liver transplantation
Authors: Takada Yasutsugu , Ueda Mikiko , Ishikawa Yukika , Fujimoto Yasuhiro , Miyauchi Hideaki , Ogura Yasuhiro , Ochiai Takenori , Tanaka Koichi
Published: May 2004

In the development of adult-to-adult living donor liver transplantation (LDLT), the small-for-size graft has been associated with poor clinical outcome. Persistent portal hypertension or portal venous overperfusion are considered to be causative factors, and partial diversion of portal flow to systemic circulation may be effective for avoiding injuries that occur in the small-for-size (SFS) graft. Recently, we constructed an end-to-side portocaval shunting using 1 of the portal branches and anastomosed the other branch with the portal vein of the graft in 2 cases of LDLT recipients transplanted with a SFS graft. With the suppression of portal hypertension, as well as sufficient portal flow to the graft, the recipients recovered successfully with favorable graft function. This new and simple technique may be able to be used as a feasible and effective method to attenuate the SFS syndrome. (Liver Transpl 2004;10:807-810.)
Significant enhancement by anti-ICOS antibody of suboptimal tacrolimus immunosuppression in rat liver transplantation
Authors: Guo Lei , Li Xiao-Kang , Enosawa Shin , Funeshima Naoko , Suzuki Seiichi , Kimura Hiromitsu , Sugawara Yasuhiko , Tezuka Katsunari , Makuuchi Masatoshi
Published: May 2004

A member of the costimulatory molecule family, inducible costimulator (ICOS), is expressed on activated T cells and plays a critical role in their primary activation and cytokine production. ICOS is involved in different immune phenomena, such as Th1-mediated autoimmune disease and graft rejection. Although blockade of ICOS costimulation theoretically may protect grafts from rejection, a single dose of anti-ICOS antibody did not result in the prolongation of rat liver allograft survival. However, in this article, we report that anti-rat ICOS antibody markedly enhanced the immunosuppressive activity of a suboptimal dose of tacrolimus (FK506). After fully allogenic DA to LEW liver transplantation, recipients received a single injection of tacrolimus (1 mg/kg, intramuscularly) with or without anti-ICOS antibody (1 mg/kg, intravenously). Recipient survival was significantly prolonged in rats treated with both the antibody and suboptimal tacrolimus (median survival time 44 days vs. 28 days with tacrolimus alone, P < .01). The extent of cell infiltration into the graft was closely associated with prolongation of recipient survival. Our findings thus demonstrate that anti-ICOS antibody immunotherapy combined with suboptimal tacrolimus has a synergistic effect in preventing hepatic allograft rejection and that it may induce long-term graft acceptance intimately associated with a marked reduction of intragraft T lymphocyte infiltration. (Liver Transpl 2004;10:743-747.)
Optimal cycle of intermittent portal triad clamping during liver resection in the murine liver
Authors: Kang Koo-Jeong , Jang Jae Hwi , Lim Tae Jin , Kang Yuna , Park Kwan Kyu , Lee In Seon , Clavien Pierre-Alain
Published: May 2004

We designed this experimental study to determine the optimal cycle for intermittent inflow occlusion during liver resection. A cycle of intermittent clamping (IC) for 15 minutes of ischemia followed by reperfusion for 5 minutes during liver resection is currently the most popular protocol used by experienced liver centers. As each period of reperfusion is associated with bleeding, longer periods of clamping would be advantageous. However, the longest safe duration of successive ischemia is unknown. Three groups of mice were subjected to a total liver ischemic period for 90 minutes; 2 groups underwent IC for 15 or 30 minutes, respectively, followed by 5 minutes of reperfusion, while the control group was subjected to continuous inflow occlusion only. The degree of tissue injury was assessed using biochemical and histological markers, as well as animal survival. While serious injury was observed in the continuous clamping group, both IC groups were associated with minimal injury, including lesser degrees of apoptosis and necrosis. All animals survived in the IC groups, while all animals died following 90 minutes of continuous inflow occlusion. In conclusion, intermittent portal pedicle clamping with 15- or 30-minute cycles is highly protective. A period of 30 minutes clamping should be preferred, since this would decrease the amount of blood loss associated with each cycle. This data should be confirmed in humans, and may represent a change in the current practice of hepatic surgery. (Liver Transpl 2004;10:794-801.)
Umbilical portion of recipient’s left portal vein: A useful vascular conduit in dual living donor liver transplantation for the thrombosed portal vein
Authors: Moon DeokBog , Lee SungGyu , Hwang Shin , Park KwangMin , Kim KiHun , Ahn ChulSoo , Lee YoungJoo , Ha TaeYong , Cho SeongHun , Oh KiBong , Kim YeonDae , Kim KeonKuk
Published: May 2004

We considered performing living donor liver transplantation (LDLT) in a larger-size recipient. When the recipient was large-sized, or when the donor liver was severely steatotic or had a right-to-left volume discrepancy. We devised dual living donor liver transplantation (DLDLT) to make up for graft size insufficiency and to secure the donor’s safety. However, portal vein thrombosis (PVT) presented a challenge for DLDLT because of the need for intact right and left portal veins for the implantation of both liver grafts. Our 52-year-old male patient with hepatitis B cirrhosis had suffered from repeated esophageal and gastric variceal bleeding and underwent 2 trials of a transjugular intrahepatic portosystemic shunt (TIPS). He developed TIPS occlusion and PVT involving the area just above the spleno-mesenteric confluence to the right and left PV. Also, the right PV orifice was destructed and difficult to isolate because of severe periportal inflammation and neointima growth in the TIPS mesh. The patient’s two sons were inadequate for donation because of right-to-left volume discrepancy. Therefore, DLDLT using 2 left lobes was necessary to compensate for graft-size insufficiency and to secure donor safety, and we substituted an intact umbilical portion of recipient’s left PV for the destroyed right PV. The patient recovered well, and liver function has been normal for more than a year. In conclusion, the umbilical portion of recipient’s left PV can be a useful vascular substitute for the reconstruction of a thrombosed main portal branch in DLDLT. (Liver Transpl 2004;10:802-806.)
Molecular Dynamics Simulations of Cellulose Oligomers: Conformational Analysis
Authors: Queyroy Séverine , Müller‐Plathe Florian , Brown David
Published: May 2004

Summary: The results of classical molecular simulations of cellulose oligomers are presented here. The conformations of the chains in the high temperature melt, room temperature quenched melt and gas phase are compared with respect to various geometrical parameters including square end‐to‐end distances, glycosidic link torsion correlations, ring puckering and hydrogen bonding. The cellulose oligomer melts were relaxed at 800 K with molecular dynamics, and then cooled down in three different ways to obtain dense amorphous systems at 500 K and at room temperature. The sample resulting from the quench (step) shows too much similarity with the melt at 800 K. The two other cooling schemes (ramp, 2ramps) give very similar results for all quantities investigated. The relevance of previous single molecule calculations with respect to the dense amorphous systems is called into question. Comparisons between the chains in the dense systems and those in the gas phase reveal that, even for these relatively short stiff chains, differences exist in the preferred conformations. At high temperatures, where both systems are in equilibrium, the distribution of square end‐to‐end distances are both fairly smooth, but the gas phase clearly prefers more compact conformations. At 300 K, the differences are exacerbated as the equilibrium distribution for the gas phase shows a high proportion of folded conformers, whereas the nonequilibrium quenched systems necessarily retain the extended envelope of the higher temperature. Differences are also evident in the puckering, the rotation of the hydroxymethyl groups and the pattern of hydrogen bonds.

The probability density distribution for the square end‐to‐end distance for octaose in the gas phase (light line) and in the dense phase (dark line) at 300 K.

image

The probability density distribution for the square end‐to‐end distance for octaose in the gas phase (light line) and in the dense phase (dark line) at 300 K.
Differential c‐myc expression profiles in normal human bronchial epithelial cells following treatment with benzo[a]pyrene, benzo[a]pyrene‐4,5 epoxide, and benzo[a]pyrene‐7,8‐9,10 diol epoxide
Authors: Fields Wanda R. , Desiderio Joseph G. , Leonard Randi M. , Burger Ellen E. , Brown Buddy G. , Doolittle David J.
Published: May 2004

Bronchial epithelial cells are often exposed to airborne mutagens that have the potential to induce genetic changes involved in the development of lung cancer. Although lung tumors often display alterations in the expression of oncogenes and/or tumor suppressor genes, the role of specific chemicals and/or metabolites in causing these alterations is not well defined. The polycyclic aromatic hydrocarbon (PAH) benzo[a]pyrene (B[a]P), a by‐product of combustion, is a prevalent airborne environmental mutagen and a constituent of cigarette smoke. The primary objective of this study was to compare the effect of B[a]P and two of its reactive metabolites, benzo[a]pyrene diol epoxide (BPDE or bay region epoxide) and benzo[a]pyrene‐4,5‐dihydroepoxide (BPE or K‐region epoxide), on expression of the proto‐oncogene c‐myc in normal human bronchial epithelial (NHBE) cells using a quantitative reverse transcriptase‐polymerase chain reaction (RT‐PCR) method. Changes in c‐myc gene expression were compared with DNA adduct formation, growth inhibition, and cell‐cycle progression as determined by 32P‐postlabelling, neutral red (NR), and flow cytometric analyses, respectively. None of the three test compounds altered the levels of 18S ribosomal RNA or β‐actin at the concentrations evaluated for c‐myc expression, indicating that nonspecific changes in gene expression induced by cytotoxicity, for example, were not present at the concentrations evaluated. Cells exposed to B[a]P exhibited a dose‐dependent increase in c‐myc expression; conversely, a dose‐dependent decrease in c‐myc expression was observed following BPDE exposure. A marginal but concentration‐dependent increase in c‐myc mRNA levels was observed following exposure to the K‐region epoxide. Our results demonstrated that, although B[a]P and its metabolites alter c‐myc expression, the parent compound and its metabolites produce unequal and contrasting effects on the expression of this gene. © 2004 Wiley‐Liss, Inc.
Reversible parkinsonism following heroin pyrolysate inhalation is associated with tetrahydrobiopterin deficiency
Authors: Heales Simon , Crawley Francesca , Rudge Peter
Published: May 2004

A patient who inhaled heroin vapour (chasing the dragon), resulting in temporary parkinsonism, is described. A reversible deficiency of tetrahydrobiopterin, causing altered dopamine metabolism, is demonstrated as the metabolic basis of this aspect of the encephalopathy. © 2004 Movement Disorder Society
In vivo imaging of microglial activation with [11C](R)‐PK11195 PET in corticobasal degeneration
Authors: Gerhard Alexander , Watts Justin , Trender‐Gerhard Iris , Turkheimer Federico , Banati Richard B. , Bhatia Kailash , Brooks David J.
Published: May 2004

Corticobasal degeneration (CBD) is a neurodegenerative parkinsonian disorder of unknown cause that shows considerable clinical heterogeneity. In CBD, activated microglia have been shown to be associated closely with the extensive tau pathology found in the affected basal ganglia, brainstem nuclei, and cortical regions. We report on the use of [11C](R)‐(1‐[2‐chlorophenyl]‐N‐methyl‐N‐[1‐methylpropyl]‐3‐isoquinoline carboxamide) (PK11195) positron emission tomography (PET), a marker of peripheral benzodiazepine binding sites (PBBS) that are expressed by activated microglia, to demonstrate in vivo the degree and distribution of glial response to the degenerative process in 4 patients with CBD. Compared with normal age‐matched controls, the CBD patient group showed significantly increased mean [11C](R)‐PK11195 binding in the caudate nucleus, putamen, substantia nigra, pons, pre‐ and postcentral gyrus, and the frontal lobe. [11C](R)‐PK11195 PET reveals a pattern of increased microglial activation in CBD patients involving cortical regions and the basal ganglia that corresponds well with the known distribution of neuropathological changes, which may therefore help to characterize in vivo the underlying disease activity in CBD. © 2004 Movement Disorder Society
NF‐κB p65 involves in reperfusion injury and iNOS gene regulation in skeletal muscle
Authors: Qi Wen‐Ning , Chaiyakit Pruk , Cai Yongting , Allen Diane M. , Chen Long‐En , Seaber Anthony V. , Urbaniak James R.
Published: May 2004

This study investigated the effects of inhibition of NF‐κB activation on microcirculation and inducible NOS expression in reperfused rat cremaster muscle. The muscle from 16 rats underwent 5‐h ischemia and 90‐min reperfusion. Each rat received NF‐κB inhibitor pyrrolidine dithiocarbamate (PDTC, 150 mg/kg) or phosphate‐buffered saline 15 min before reperfusion. Results showed that PDTC treatment had a significant overall increase in muscle blood flow during reperfusion. Blood flow more rapidly recovered to and over baseline in the PDTC‐treated group than in controls, with a significant difference at 10–30 min and 70–90 min. Expression of iNOS mRNA had a 167‐fold increase from normal in controls, but was significantly (P < 0.05) reduced to a 63‐fold increase in PDTC‐treated muscles. In addition, PDTC treatment significantly (P < 0.05) decreased a reperfusion‐induced increase in activated NF‐κB p65 and nuclear p65 protein. Our results suggest that NF‐κB is involved in I/R injury and that inhibition of NF‐κB p65 activation affords protection against I/R injury, perhaps via downregulating expression of iNOS transcription. © 2004 Wiley‐Liss, Inc.
Existence and uniqueness of bounded weak solution for non‐linear parabolic boundary value problem with equivalued surface
Authors: Li Fengquan
Published: May 2004

In this paper, we discuss the existence and uniqueness of bounded weak solution for non‐linear parabolic boundary value problem with equivalued surface and correct the mistake in Zhang Xu (Math. Meth. Appl. Sci. 1999; 22: 259). The approach is based on L∞ estimate of solution. Copyright © 2004 John Wiley & Sons, Ltd.
A relaxed model and its homogenization for nematic liquid crystals in composite materials
Authors: Shen Quan , Calderer M. Carme
Published: May 2004

We analyse a model for equilibrium configurations of composite systems of nematic liquid crystal with polymer inclusions, in the presence of an external magnetic field. We assume that the system has a periodic structure, and consider the relaxed problem on the unit length constraint of the nematic director field. The relaxation of the Oseen–Frank energy functional is carried out by including bulk as well as surface energy penalty terms, rendering the problem fully non‐linear. We employ two‐scale convergence methods to obtain effective configurations of the system, as the size of the polymeric inclusions tends to zero. We discuss the minimizers of the effective energies for, both, the constrained as well as the unconstrained models. Copyright © 2004 John Wiley & Sons, Ltd.
A Kronecker product approximate preconditioner for SANs
Authors: Langville Amy N. , Stewart William J.
Published: May 2004

Many very large Markov chains can be modelled efficiently as stochastic automata networks (SANs). A SAN is composed of individual automata which, for the most part, act independently, requiring only infrequent interaction. SANs represent the generator matrix Q of the underlying Markov chain compactly as the sum of Kronecker products of smaller matrices. Thus, storage savings are immediate. The benefit of a SAN's compact representation, known as the descriptor, is often outweighed by its tendency to make analysis of the underlying Markov chain tough. While iterative or projections methods have been used to solve the system πQ=0, the time until these methods converge to the stationary solution π is still unsatisfactory. SAN's compact representation has made the next logical research step of preconditioning thorny. Several preconditioners for SANs have been proposed and tested, yet each has enjoyed little or no success. Encouraged by the recent success of approximate inverses as preconditioners, we have explored their potential as SAN preconditioners. One particularly relevant finding on approximate inverse preconditioning is the nearest Kronecker product approximation discovered by Pitsianis and Van Loan. In this paper, we extend the nearest Kronecker product technique to approximate the Q matrix for an SAN with a Kronecker product, A1 ⊗ A2 ⊗…⊗ AN. Then, we take M = A ⊗ A ⊗…⊗ A as our SAN NKP preconditioner. Copyright © 2004 John Wiley & Sons, Ltd.
Quality improvements in extruded meshes using topologically adaptive generalized elements
Authors: Chalasani Satish , Thompson David
Published: May 2004

This paper describes a method to extrude near‐body volume meshes that exploits topologically adaptive generalized elements to improve local mesh quality. Specifically, an advancing layer algorithm for extruding volume meshes from surface meshes of arbitrary topology, appropriate for viscous fluid flows, is discussed. First, a two‐layer reference mesh is generated from the layer initial surface mesh by extruding along the local surface normals. The reference mesh is then smoothed using a Poisson equation. Local quality improvement operations such as edge collapse, face refinement, and local reconnection are performed in each layer to drive the mesh toward isotropy and improve the transition from the extruded mesh to a void‐filling tetrahedral mesh. A few example meshes along with quality plots are presented to demonstrate the efficacy of this approach. Copyright © 2004 John Wiley & Sons, Ltd.
A 3D anisotropic elastoplastic‐damage model using discontinuous displacement fields
Authors: Mosler J. , Bruhns O. T.
Published: May 2004

This paper is concerned with the development of constitutive equations for finite element formulations based on discontinuous displacement fields. For this purpose, an elastoplastic continuum model (stress–strain relation) as well as an anisotropic damage model (stress–strain relation) are projected onto a surface leading to traction separation laws. The coupling of both continuum models and, subsequently, the derivation of the corresponding constitutive interface law are described in detail. For a simple calibration of the proposed model, the fracture energy resulting from the coupled elastoplastic‐damage traction separation law is computed. By this, the softening evolution is linearly dependent on the fracture energy. The second part of the present paper deals with the numerical implementation. Based on a local and incompatible additive split of the displacement field into a continuous and a discontinuous part, the parameters specifying the jump of the displacement field are condensed out at the material level without employing the standard static condensation technique. To reduce locking effects, a rotating localization zone formulation is applied. The applicability and the performance of the proposed numerical implementation is investigated by means of a re‐analysis of a two‐dimensional L‐shaped slab as well as by means of a three‐dimensional ultimate load analysis of a steel anchor embedded in a concrete block. Copyright © 2004 John Wiley & Sons, Ltd.
Stabilized conforming nodal integration in the natural‐element method
Authors: Yoo Jeong Wahn , Moran Brian , Chen Jiun‐Shyan
Published: May 2004

A stabilized conforming nodal integration scheme is implemented in the natural neighbour method in conjunction with non‐Sibsonian interpolation. In this approach, both the shape functions and the integration scheme are defined through use of first‐order Voronoi diagrams. The method illustrates improved performance and significant advantages over previous natural neighbour formulations. The method also shows substantial promise for problems with large deformations and for the computation of higher‐order gradients. Copyright © 2004 John Wiley & Sons, Ltd.
A fully explicit characteristic based split (CBS) scheme for viscoelastic flow calculations
Authors: Nithiarasu P.
Published: May 2004

In this paper, an explicit characteristic based split (CBS) scheme is proposed for the numerical solution of incompressible viscoelastic flow equations. The scheme proposed is free from simultaneous solution to the matrices arising from the finite element discretization of the governing equations. The experience gained from the solution of Newtonian fluid dynamics problems has been applied to the solution of viscoelastic flows. The Oldroyd‐B model has been employed to solve two benchmark problems of viscoelastic flow. They are viscoelastic flow past a circular cylinder and viscoelastic flow through planar contraction geometry. The results show that the solutions obtained are stable for the Weissenberg or Deborah number range studied in this paper. The solutions obtained at lower Weissenberg or Deborah numbers are accurate and agree excellently with the majority of available numerical data. However at higher Weissenberg or Deborah numbers, results show some sign of negative influence of the artificial dissipation added to the discrete constitutive equations. Copyright © 2004 John Wiley Sons, Ltd.
Numerical simulation of the motion of a two‐dimensional glacier
Authors: Picasso Marco , Rappaz Jacques , Reist Adrian , Funk Martin , Blatter Heinz
Published: May 2004

The motion of a two‐dimensional glacier is considered. At each time step, given the shape of the glacier, ice is modelled as an incompressible non‐Newtonian fluid and a non‐linear elliptic problem has to be solved to obtain the horizontal velocity field. Then, the upper surface of the glacier is updated by solving a transport equation. Finite element techniques are used to compute the velocity field whereas the transport equation is solved using a Lax–Wendroff scheme. Numerical results are compared to experiments on Gries glacier (Wallis, Switzerland) between 1961 and 1991. Then, a predition for 2021 is proposed. Copyright 2004 John Wiley & Sons, Ltd.
Getting the fundamentals wrong: woes of public–private partnerships in solid waste collection in three Ghanaian cities
Authors: Awortwi Nicholas
Published: May 2004

Until over a decade ago, concerted efforts at involving private agents to deliver solid waste collection services did not feature in local government's (LG's) policies and practices in Ghana. The LGs had over the years directly delivered the services with their labour, materials and equipment. The purpose of entering into partnerships with private contractors was to improve service delivery. This comes at a time when the private sector is generally viewed as more efficient and effective than the public sector. There is abundant literature on potential benefits of private sector participation in public service delivery; yet, figures of efficiency gains are often accepted without challenge. More advantages but fewer disadvantages are cited and anecdotal evidence is used only to illustrate successful applications of the concept of public–private partnerships (PPPs). Using research data from three cities (Accra, Kumasi and Tema) in Ghana, this article exposes the contrast between policy expectations and outcomes of PPPs. The article argues that simply turning over public service delivery to private agents without ensuring that the fundamentals that make them successful are put in place leads to a worse situation than portrayed in literature about the benefit of PPPs. Copyright © 2004 John Wiley & Sons, Ltd.
Layered silicate polymer nanocomposites: new approach or illusion for fire retardancy? Investigations of the potentials and the tasks using a model system
Authors: Bartholmai Matthias , Schartel Bernhard
Published: May 2004

Polymeric nanocomposites are discussed as one of the most promising advanced materials whose nanoscale effects can be exploited for industry. Layered silicate polypropylene‐graft‐maleic anhydride nanocomposites are investigated as a model to clarify the potential of such materials in terms of fire retardancy. The nanostructure is characterized using transmission electron microscopy (TEM) and shear viscosity. The fire behavior is characterized using different external heat fluxes in cone calorimeter, limiting oxygen index and UL 94 classification. A comprehensive fire behavior characterization is presented which enables an assessment of the materials' potential with respect to different fire scenarios and fire tests. The influence of morphology and the active mechanisms are discussed, such as barrier formation and changed melt viscosity. To our knowledge, it is the first attempt to illuminate the concept's strengths, such as the reduction of flame spread, and weaknesses, such as the lack of influence on ignitability, in a clear, comprehensive and detailed manner. Copyright © 2004 John Wiley & Sons, Ltd.