bluuebunny/crossref_metadata_2025_split huggingface dataset:
Simulation of willow short‐rotation forest evaporation using a modified Shuttleworth–Wallace approach
Authors: Iritz Z. , Tourula T. , Lindroth A. , Heikinheimo M. 
Published: August 2002

AbstractEvaporation from a willow short‐rotation forest was analysed using a modified version of the Shuttleworth–Wallace model. The main modification consisted of a two‐layer soil module, which enabled soil surface resistance to be calculated as a function of the wetness of the top soil. Introduction of the threshold value of the leaf area index when scaling up from the leaf to the canopy resistance resulted in improvement to the simulated evaporation. The analysis was concentrated mainly on the 1988 season (May–October) when total evaporation was measured by the energy balance/Bowen ratio method throughout the growing season, covering all stages of canopy development. At the beginning of the 1994 season, soil evaporation were also measured with a ventilated chamber system. The general seasonal dynamics of the evaporation were fairly well simulated with the model. The largest deviation between measured and simulated evaporation occurred in June, when the model underestimated evaporation by about 1 mm day−1. The model underestimated also in May but not as much as in June. In September and October the performance of the model was very good. For 130 days of the period May–October the cumulated measured evaporation was 364 mm and the simulated evaporation for the same days was 362 mm. It should be pointed out that this result was obtained without calibrating the model against the measured evaporation. The total simulated evaporation for the season was 450 mm with transpiration constituting 298 mm (66%), soil evaporation 102 mm (23%) and interception evaporation 50 mm (11%). The sensitivity analysis showed, in general, that simulated evaporation was most sensitive to changes in resistances when the leaf area index was smallest, i.e. under non‐closed canopy conditions. Changes in stomatal resistance, which is one of the most sensitive parameters, with associated changes in canopy transpiration, resulted in a negative feedback effect on soil evaporation. This reduced the total evaporation's sensitivity to stomatal resistance. This type of interaction between canopy and soil or undergrowth fluxes has been observed in other studies as well. Copyright © 2001 John Wiley & Sons, Ltd.
Spatial patterns of suspended sediment yields in a humid tropical watershed in Costa Rica
Authors: Krishnaswamy Jagdish , Richter Daniel D. , Halpin Patrick N. , Hofmockel Michael S. 
Published: August 2002

AbstractAn Erratum has been published for this article in Hydrological Processes 16(5) 2002, 1130–1131.
Humid tropical regions are often characterized by extreme variability of fluvial processes. The Rio Terraba drains the largest river basin, covering 4767 km2, in Costa Rica. Mean annual rainfall is 3139±419sd mm and mean annual discharge is 2168±492sd mm (1971–88). Loss of forest cover, high rainfall erosivity and geomorphologic instability all have led to considerable degradation of soil and water resources at local to basin scales. Parametric and non‐parametric statistical methods were used to estimate sediment yields.In the Terraba basin, sediment yields per unit area increase from the headwaters to the basin mouth, and the trend is generally robust towards choice of methods (parametric and LOESS) used. This is in contrast to a general view that deposition typically exceeds sediment delivery with increase in basin size. The specific sediment yield increases from 112±11·4sd t km−2 year−1 (at 317·9 km2 on a major headwater tributary) to 404±141·7sd t km−2 year−1 (at 4766·7 km2) at the basin mouth (1971–92). The analyses of relationships between sediment yields and basin parameters for the Terraba sub‐basins and for a total of 29 basins all over Costa Rica indicate a strong land use effect related to intensive agriculture besides hydro‐climatology. The best explanation for the observed pattern in the Terraba basin is a combined spatial pattern of land use and rainfall erosivity. These were integrated in a soil erosion index that is related to the observed patterns of sediment yield. Estimated sediment delivery ratios increase with basin area. Intensive agriculture in lower‐lying alluvial fans exposed to highly erosive rainfall contributes a large part of the sediment load. The higher elevation regions, although steep in slope, largely remain under forest, pasture, or tree‐crops. High rainfall erosivity (>7400 MJ mm ha−1 h−1 year −1) is associated with land uses that provide inadequate soil protection. It is also associated with steep, unstable slopes near the basin mouth.Improvements in land use and soil management in the lower‐lying regions exposed to highly erosive rainfall are recommended, and are especially important to basins in which sediment delivery ratio increases downstream with increasing basin area. Copyright © 2001 John Wiley & Sons, Ltd.
Concurrent overexpression of ETS‐1 and C‐met correlates with a phenotype of high cellular motility in human esophageal cancer
Authors: Saeki Hiroshi , Oda Shinya , Kawaguchi Hidetoshi , Ohno Shinji , Kuwano Hiroyuki , Maehara Yoshihiko , Sugimachi Keizo 
Published: August 2002

AbstractHepatocyte growth factor (HGF) stimulates cell motility as well as mitotic activity of cells. High concentrations of HGF or overexpression of its cellular receptor c‐Met in cancer have been reported. We analyzed the expression status of c‐Met immunohistochemically in 76 cases of human esophageal cancer. Overexpression of c‐Met was noted at a considerably high frequency. Intriguingly, c‐Met overexpression was frequent in a specific type of cell nest formation in tumors, i.e., the small nest type, in which tumors form small, dispersed cell nests. Further immunohistochemical analyses using serial sections revealed a striking coincidence between overexpression of c‐Met and its transcriptional factor, Ets‐1. Overexpression of c‐Met and Ets‐1 was statistically more frequent in small nest type tumors. The close correlation in expression status between Ets‐1 and c‐Met was also confirmed using 6 established human esophageal cancer cell lines. In addition, cells that expressed high levels of Ets‐1 and c‐Met exhibited an extremely motile phenotype by HGF stimulation in vitro. The presence of HGF in tissue sections was confirmed using similar immunohistochemical approaches. These observations suggest that in human esophageal cancer cells the transcriptional factor Ets‐1 upregulates the expression of c‐Met and, consequently, confers on cells a highly motile phenotype leading to a specific form of tumor development. © 2001 Wiley‐Liss, Inc.
In situ repair of cyclobutane pyrimidine dimers in skin and melanocytic nevi of cutaneous melanoma patients
Authors: Zhao Chunyan , Snellman Erna , Jansen Christer T. , Hemminki Kari 
Published: August 2002

AbstractThe development of cutaneous malignant melanoma (CMM) and its precursor lesions, melanocytic nevi, has been linked to sun exposure. Cyclobutane pyrimidine dimers (CPDs) are the majority of DNA lesions induced by sun exposure. In our study, we investigated if CMM patients have impaired ability to repair CPDs in skin as well as in melanocytic nevi. The repair kinetics were followed up to 3 weeks after exposure to 40 mJ/cm2 of solar simulating radiation. Altogether 12 CMM patients and 10 healthy controls were included in our study. Buttock skin biopsies were taken at 0 hr, 48 hr and 3 weeks after UV exposure, whereas melanocytic nevi and surrounding skin biopsies were taken only at 0 hr and 3 weeks. The CPD levels were measured by a 32P‐postlabeling method. The results showed that the repair rate of CPDs in neither the skin nor the nevi was significantly different between the CMM patients and the control group. For both groups, the repair rate of TT = C was faster than that for TT = T. The important finding is that about 10% of the initial TT = T damage remained unrepaired after 3 weeks, and was detectable in normal epidermis as well as in nevi of all subjects. We also found that the amount of TT = C and TT = T at 0 hr in nevi was significantly lower than that in surrounding skin (Wilcoxon rank sum test, p < 0.05). © 2002 Wiley‐Liss, Inc.
Assessment of genomic instability in breast cancer and uveal melanoma by random amplified polymorphic DNA analysis
Authors: Papadopoulos Sarantos , Benter Thomas , Anastassiou Gerasimos , Pape Michael , Gerhard Schaller , Bornfeld Norbert , Ludwig Wolf‐Dieter , Dörken Bernd 
Published: August 2002

AbstractSome types of cancer have been associated with abnormal DNA fingerprinting. We used random amplified polymorphic DNA (RAPD) to generate fingerprints that detect genomic alterations in human breast cancer. Primers were designed by choosing sequences involved in the development of DNA mutations. Seventeen primers in 44 different combinations were used to screen a total of 6 breast cancer DNA/normal DNA pairs and 6 uveal melanoma DNA/normal DNA pairs. Forty‐five percent of these combinations reliably detected quantitative differences in the breast cancer pairs, while only 18% of these combinations detected differences in the uveal melanoma pairs. Fourteen (32%) and 12 (27%) primers generated a smear or did not produce any band patterns in the first and second cases, respectively. Taking into account the ability of RAPD to screen the whole genome, our results suggest that the genomic damage in breast cancer is significantly higher than in uveal melanoma. Our study confirms other reports that the molecular karyotypes produced with random priming, called amplotypes, are very useful for assessing genomic damage in cancer. © 2002 Wiley‐Liss, Inc.
Protease inhibitors restore radiation‐induced apoptosis to Bcl‐2‐expressing lymphoma cells
Authors: Kurland John F. , Meyn Raymond E. 
Published: August 2002

AbstractThe proteasome pathway is important for the turnover of many regulatory proteins. This pathway has recently become a target for antitumor agents and several research groups have demonstrated that inhibitors with specificities for the proteasome are potent apoptosis‐inducing agents. Many mechanisms by which proteasome inhibitors exert their effects have been suggested, including inhibition of NF‐κB activity and stabilization of the p53 tumor suppressor protein. We investigated the ability of inhibitors with specificities for the proteasome and for another protein degradation enzyme, calpain, to sensitize a murine B‐cell lymphoma with constitutive NF‐κB1 homodimer activity and high expression of Bcl‐2 protein to radiation‐induced apoptosis. Protease inhibitors tested were calpain inhibitor I, calpain inhibitor II, calpeptin, MG132, and Lactacystin. All five inhibitors induced apoptosis and sensitized cells to radiation despite the maintenance of Bcl‐2 protein levels throughout the course of treatment. An electrophoretic migration shift assay for NF‐κB1 activity provided evidence that reversal of NF‐κB activity was not required for induction of cell death; however, p53 levels were elevated for all inhibitors tested. HL‐60 cells, devoid of p53, could not be sensitized to radiation by MG132 treatment, suggesting that p53 was important for cell death induced by combined treatment with protease inhibitors and radiation. We concluded that protease inhibitors are capable of overcoming the protective effects of Bcl‐2 to induce apoptosis and suggest that protease inhibitor treatment, when combined with ionizing radiation, leads to p53‐mediated apoptosis. © 2001 Wiley‐Liss, Inc.
Mitotic arrest induced by XK469, a novel antitumor agent, is correlated with the inhibition of cyclin B1 ubiquitination
Authors: Lin Hong , Liu Xiang Y. , Subramanian Balanehru , Nakeff Alexander , Valeriote Fred , Chen Ben D. 
Published: August 2002

AbstractXK469 (NSC 697887) is a novel antitumor agent with broad activity against a variety of tumors. Previous studies suggest that XK469 is a topoisomerase IIβ poison with functional activity similar to that of 4′‐(9‐acridinylamino) methanesulfon‐m‐anisidide (m‐AMSA). The goal of our study was to investigate its mechanism of action further using a human HCT‐116 (H116) colon tumor cell model. Concentration‐survival curves with continuous exposure indicated that XK469 had low cytotoxic activity against H116 cells. Cell cycle analysis revealed that XK469 is a phase‐specific cell cycle blocker that is associated with increased levels of cyclin B1, cyclin A and p53 but not CDK1 (cdc2) or cyclin E. In contrast, treatment of H116 cells with m‐AMSA caused a total degradation of both cyclin A and B1 but enhanced expression of cyclin E and p53. Accumulation of cyclin B1 in XK469‐treated cells was correlated with the inhibition of cyclin B1 ubiquitination, a metabolic process mandatory for proteasome‐mediated protein turnover. However, no inhibition of cyclin B1 ubiquitination was detected in cells treated with m‐AMSA or colchicine, a known mitotic inhibitor. Furthermore, unlike m‐AMSA, XK469 did not induce caspase activation or apoptotic cell death in H116 cells. Our results suggest that XK469 is a phase‐specific cell cycle inhibitor with a unique mechanism of action that is correlated with the inhibition of cyclin B1 ubiquitination and its accumulation at early M phase. © 2002 Wiley‐Liss, Inc.
Combined gemcitabine and radioimmunotherapy for the treatment of pancreatic cancer
Authors: Cardillo Thomas M. , Blumenthal Rosalyn , Ying Zhiliang , Gold David V. 
Published: August 2002

AbstractMAb‐PAM4 is an anti‐MUC1 antibody that has been shown to be reactive with 85% of pancreatic adenocarcinomas with no reactivity with normal pancreas or other tissues. Initial clinical studies have shown excellent targeting with high tumor/nontumor ratios. Gemcitabine, an analog of deoxycytidine, is currently a frontline treatment for pancreatic cancer. Acting via a number of metabolic pathways, gemcitabine is also a powerful radiosensitizer. Combined‐modality, chemo/radiosensitization with gemcitabine and low dose 131I‐PAM4 radioimmunotherapy was performed to determine if a more effective treatment procedure could be developed. Athymic nude mice bearing large (1 cm3) CaPan1 human pancreatic tumors were given a single treatment cycle consisting of gemcitabine, 333 mg/m2 administered on Days 0, 3, 6, 9 and 12 by intraperitoneal injection, along with either 100 or 200 μCi, 131I‐PAM4 administered on Day 0 by intravenous injection. Gemcitabine did not interfere with the biodistribution of radiolabeled antibody. Specific tumor targeting was observed for 131I‐PAM4, with a tumor/blood radiation dose ratio of 2.6 over the first 14 days. Gemcitabine alone and low dose radioimmunotherapy alone, each had no affect upon tumor growth; no statistical differences were noted in comparison to the untreated group. When combined, however, a statistically significant (p = 0.0324), synergistic anti‐tumor effect was observed. Median survival time doubled for the combined treatment regimen compared to single modality treatment groups. The combined treatment modality was well tolerated by the mice. Our data show that combined gemcitabine with radioimmunotherapy may provide an improved alternative for the treatment of pancreatic cancer, achieving successful anti‐tumor effects with low toxicity. © 2001 Wiley‐Liss, Inc.
Debt management in Brazil: evaluation of the real plan and challenges ahead
Authors: Bevilaqua Afonso S. , Garcia Márcio G.P. 
Published: August 2002

AbstractThe Brazilian domestic debt has posed two challenges to policy‐makers: it has grown very fast and its maturity is extremely short. This has prompted fears that a default or a compulsory lengthening scheme would be imposed. Here, we analyse the domestic public debt management experience in Brazil, searching for policy prescriptions for the next few years. After briefly reviewing the recent domestic public debt history, we decompose the large rise in federal bonded debt during 1995–2000, searching for its macroeconomic causes. The main culprits are the extremely high interest payments—which, until 1998, were caused by the weak fiscal stance and the quasi‐fixed exchange‐rate regime; and since 1999, by the impact of the currency depreciation on the dollar‐indexed and the external debt—, and the accumulation of assets of doubtful value, much of which may have to be written off in the future. Simulation exercises of the net debt path for the near future underscore the importance of a tighter fiscal stance to prevent the debt‐GDP ratio from growing further. Given the need to quickly lengthen the debt maturity, our main policy advice is to foster, and rely more on, inflation‐linked bonds. Copyright © 2002 John Wiley & Sons, Ltd.
Mother–infant communication can be enhanced after conception by in‐vitro fertilization
Authors: Papaligoura Zaira , Trevarthen Colwyn 
Published: August 2002

AbstractTo determine if stress associated with artificial pregnancy treatment might affect early communication, video microanalysis was applied to examine face‐to‐face play between infants and their mothers in the first 5 months. Three groups of infants participated: 8 born after in‐vitro fertilization (IVF) treatment employing parental gametes; 8 born after standard infertility treatment (INF), which did not include IVF; and 8 infants whose parents had experienced no infertility problems (Control group: C). All were videotaped at home in free play with their mothers at 4, 7, 13, and 21 weeks of age. A 3‐min extract of each video was reviewed in detail by means of an objective coding system, to define the style of communication. Data from this analysis was subjected to two separate repeated measures of analyses of variance.We found no evidence of detrimental effects of infertility treatment on mother–infant communication, but there were “positive” differences in behavior in the pairs where the mother had been so treated. Thus, while maternal “caretaking” episodes had become infrequent in the control group by the age of 21 weeks, in the two treatment groups the mothers continued to show many caretaking behaviors with infants of this age. Furthermore, infants of both the IVF and INF groups showed significantly higher frequencies of “play” episodes than those in the control group (p = 0.018 and p = 0.004, respectively). Apart from these differences, mother–infant interactions were generally the same in the three groups.The results indicate that communication between mothers and infants is likely to develop along the normal path after IVF or INF treatment, but that mothers who have had these infertility treatments may be more attentive to their infants, and their infants are significantly more playful. Since the IVF and the INF groups were similar, it would appear that these differences from the control group are related to the experience of a successful treatment for infertility, and not related to any particular stresses that may be associated with IVF treatment. ©2001 Michigan Association for Infant Mental Health.
Composites consisting of poly(methyl methacrylate) and alumina powder: An evaluation of their mechanical and biological properties
Authors: Shinzato Shuichi , Nakamura Takashi , Kokubo Tadashi , Kitamura Yoshiro 
Published: August 2002

AbstractWe developed new composites consisting of comparatively high molecular weight poly(methyl methacrylate) (hPMMA) and δ‐alumina powder or α‐alumina powder (designated δ‐APC and α‐APC, respectively) that allowed direct bone formation on their surfaces in vivo. δ‐Alumina powder was manufactured by the fusing and quenching of pulverized alumina powder. It was composed mainly of δ‐crystal phases of alumina. The purpose of this study was to evaluate the static mechanical properties and biological properties of these composites. The hPMMA itself was used as a reference material. The bending strength and Young's modulus of both δ‐APC and α‐APC were significantly higher than those of hPMMA, and the alumina composites are believed to be strong enough for use under weight‐bearing conditions. The three types of composites were packed into the intramedullary canals of rat tibiae to evaluate osteoconductivity, as determined by an affinity index. Rats were sacrificed 4 and 8 weeks after surgery. The affinity index, equal to the length of bone in direct contact with the composite surface and expressed as a percentage of the total length of the composite surface, was calculated for each composite at each interval. Histologically, new bone had formed along the surfaces of both δ‐APC and α‐APC within 4 weeks. The affinity indices for both δ‐APC and α‐APC increased significantly with time up to 8 weeks. At 8 weeks, the affinity index for δ‐APC was significantly higher than the indices for α‐APC and hPMMA. This study revealed that the excellent osteoconductivity of δ‐APC was due to the δ‐crystal phases of alumina and the high molecular weight of hPMMA. δ‐APC shows promise as a base for developing a highly osteoconductive and mechanically strong biomaterial. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res 60: 585–591, 2002
Membrane‐encased polymer millirods for sustained release of 5‐fluorouracil
Authors: Qian Feng , Nasongkla Norased , Gao Jinming 
Published: August 2002

AbstractThis article describes the design and development of a novel membrane‐encased polymer millirod for the sustained release of an anticancer drug, 5‐fluorouracil (5‐FU). The millirod consists of two functional compartments: (1) an inner 5‐FU‐loaded monolithic millirod as the drug depot, and (2) an outer NaCl‐impregnated polymer membrane to control the release rate of 5‐FU. The inner millirod is fabricated by a compression‐heat molding procedure to permit the entrapment of 5‐FU particles in the poly(D,L‐lactide‐co‐glycolide) (PLGA) matrix. The drug loading density is controlled at 30 w/w% to achieve a burst release of 5‐FU (>90% of the drug are released within 48 h) from the monolithic millirod. The NaCl‐impregnated PLGA membrane is generated by solvent casting and is then wrapped over the monolithic millirod to produce the membrane‐encased millirod. Scanning electron microscopy shows that dissolution of NaCl particles produces a semipermeable polymer membrane to provide a sustained release of 5‐FU. The membrane thickness and the density of NaCl particles inside the membrane are useful parameters to control the release kinetics of 5‐FU. Under the experimental conditions in this study, sustained release of 5‐FU [rates between 0.1 and 0.4 mg/(day · cm of millirod)] is achieved for 2 to 5 weeks in phosphate‐buffered saline (pH 7.4) at 37°C. Results from this study demonstrate that membrane‐encased polymer millirods provide controllable sustained release kinetics for applications in intratumoral drug delivery. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res 61: 203–211, 2002
Effect of water vapor treatment on apatite formation on precalcified titanium and bond strength of coatings to substrates
Authors: Feng B. , Chen Y. , Zhang X.D. 
Published: August 2002

AbstractIn previous investigations, a simple method, precalcification, was developed for bioactivating titanium. After a titanium sample was precalcified in a boiling saturated Ca(OH)2 solution and then immersed in a calcium phosphate supersaturated solution, an apatite coating rapidly precipitated onto its surface. In the present study, heat‐treatment in water vapor was carried out prior to precalcification. Heat‐treatment in water vapor stimulated the chemical reaction between titanium, calcium, and phosphate. Coating properties were improved, and the bond strength of the coating to substrate was enhanced. © 2001 Wiley Periodicals, Inc. J Biomed Mater Res 59: 12–17, 2002