bluuebunny/crossref_metadata_2025 huggingface dataset:
Water management structures in Europe
Authors: Dirksen Wolfram
Published: October 2002

Water management nowadays is experienced as an area of conflict, increasingly determined by the conflicting demands of the different water users, including nature. The World Water Council therefore initiated a worldwide appraisal of national water resources management policies and practices. The European Regional Working Group (ERWG) of the International Commission on Irrigation and Drainage (ICID) was engaged to prepare the European Sector Vision on Water for Food and Rural Development.

As a result the ERWG delivered a study with a condensed portrayal of continental water policies complemented by 15 national reports, which for the first time provided a comprehensive insight into the water management of the various contributing countries, including political and legal mechanisms, expected environmental challenges, requirements of the users, and organisational and institutional solutions.

Modern water legislation pursues the target of balancing the requirements of human needs and nature conservation by sustainable planning and public participation, the cornerstones of the Water Framework Directive of the European Union. The ERWG study demonstrates the different systems and mechanisms developed by European countries to meet this target. With a view to the future unifying of Europe, national regulations have to be harmonised and transformed into a European water policy. Organisational structures like basin administrations, water management associations, technical–scientific societies, and private and co‐operative facilities will have an increasing role.

This paper highlights the findings achieved by the ERWG study and will give an impression of the manifold solutions. Experience gathered in Spain, France, Slovenia and Hungary will provide knowledge for the development of environmentally sound and market‐oriented water management systems. Copyright © 2002 John Wiley & Sons, Ltd.
Twelve theses on the cost and use of irrigation water
Authors: Merrett Stephen
Published: October 2002

The published literature on the economics of irrigation is extensive and complex. This brief paper provides a clear and succinct account of the linkage between the cost of irrigation water to farmers and the volume of water that they use. Its main aim is to set out the conditions under which an increase in the cost of water is likely to reduce the rate of growth in volume used. The paper is unusual in its format and takes the form of 12 theses with a bibliography of key reading. Copyright © 2002 John Wiley & Sons, Ltd.
Crack spread hedging: accounting for time‐varying volatility spillovers in the energy futures markets
Authors: Haigh Michael S. , Holt Matthew T.
Published: October 2002

Crude oil, heating oil, and unleaded gasoline futures contracts are simultaneously analysed for their effectiveness in reducing price volatility for an energy trader. A conceptual model is developed for a trader hedging the ‘crack spread’. Various hedge ratio estimation techniques are compared to a Multivariate GARCH model that directly incorporates the time to maturity effect often found in futures markets. Modelling of the time‐variation in hedge ratios via the Multivariate GARCH methodology, and thus taking into account volatility spillovers between markets is shown to result in significant reductions in uncertainty even while accounting for trading costs. Copyright © 2002 John Wiley & Sons, Ltd.
Evaluation of genotoxic damage of cadmium chloride in peripheral blood of suckling Wistar rats
Authors: Kašuba Vilena , Rozgaj Ružica , Sarić Marijana Matek , Blanuša Maja
Published: October 2002

The aim of this study was to evaluate possible genotoxic damage of cadmium chloride exposure in suckling rats by means of the comet assay and the in vivo micronucleus test of rat blood lymphocytes, because no information is available on the genotoxic effect of cadmium in rats at this early age. Pups were receiving cadmium (as CdCl2·H2O) orally in fractions of 0.5 mg for 9 days, totalling 4.5 mg Cd kg−1 body wt, or were given a single subcutaneous injection of 0.5 mg Cd kg−1 body wt. Some pups in both exposed groups were receiving calcium supplement (CaHPO4·2H2O) in feed to reduce the body load of cadmium. Control pups did not receive either cadmium or calcium supplement. Cadmium in the carcass and organs was measured by atomic absorption spectrometry. The results showed that the cadmium body burden was significantly lower when the animals were receiving calcium supplements along with oral cadmium. The results of the micronucleus and comet assays showed significant differences between the control and exposed groups, regardless of the route of cadmium administration. The only statistically significant difference between the two exposed groups (oral cadmium and oral cadmium + calcium supplements) was in the number of micronuclei. The results of the comet assay showed that tail length differed statistically only between the control and all exposed groups, regardless of the route of cadmium administration. It can be concluded that the applied cadmium doses caused detectable genome damage but it was lower in calcium‐treated pups receiving cadmium orally. Copyright © 2002 John Wiley & Sons, Ltd.
Genetic synthesis and characterization of pH‐ and temperature‐sensitive silk‐elastinlike protein block copolymers
Authors: Nagarsekar Ashish , Crissman John , Crissman Mary , Ferrari Franco , Cappello Joseph , Ghandehari Hamidreza
Published: October 2002

The purpose of this work was to synthesize and characterize a pH‐ and temperature‐sensitive block copolymer containing repeating sequences from silk (Gly–Ala–Gly–Ala–Gly–Ser) and elastin (Gly–Val–Gly–Val–Pro) protein. The monomer contained one repeat of silk and eight repeat units of elastin, with the first valine in one of the elastin repeats being replaced by glutamic acid. The copolymer was synthesized using genetic engineering techniques. The sensitivity of the copolymer to pH and temperature was examined at various polymer concentrations and ionic strengths. Turbidity measurements were carried out over a temperature range of 20 to 100°C at various pH, concentration, and ionic strength values. The introduction of an ionizable residue (glutamic acid) rendered the copolymer sensitive to changes in pH. The transition termperature (Tt), the temperature at which the polymer became insoluble upon increase in temperature, was modulated by changing the pH. In general, the Tt value, was found: (1) to increase with an increase in pH, (2) to decrease with increasing ionic strength, and (3) to decrease with increasing concentration. Results of these studies suggest that by strategic placement of charged amino acids in genetically engineered silk‐elastinlike protein block copolymers it is possible to precisely control sensitivity to stimuli such as pH and temperature. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res 62: 195–203, 2002
Direct hemoperfusion using a polymyxin B immobilized column improves acute respiratory distress syndrome
Authors: Tsushima Kenji , Kubo Keishi , Koizumi Tomonobu , Yamamoto Hiroshi , Fujimoto Keisaku , Hora Kazuhiko , Kan‐nou Yutaka
Published: October 2002

Acute respiratory distress syndrome (ARDS) is characterized by a high mortality rate. We have studied whether direct hemoperfusion using a polymyxin B immobilized fiber column (PMX‐DHP) is effective for acute lung injury (ALI) and ARDS. Two ALI and eighteen ARDS patients were evaluated, four congestive heart failure (CHF) patients were evaluated as cardiogenic pulmonary edema, and we retrospectively compared the outcome with ten patients with ARDS who had been hospitalized between 1990 and 1998 as the untreated group. PMX‐DHP was carried out twice at a rate of 80–100 ml/minute for 2 hours, with a time interval of approximately 24 hours. We monitored systolic blood pressure (BP), diastolic BP, and the PaO2/FIO2 (PF) ratio before and after PMX‐DHP treatment. The mortality was classified if patients were alive at day 30 after initiating PMX‐DHP. The mortality of ARDS patients was approximately 20%. Systolic BP increased significantly from 106 ± 20 to 135 ± 21 and to 125 ± 20 mmHg on the following day. Diastolic BP increased from 61 ± 16 to 78 ± 15, and to 72 ± 12 mmHg. The PF ratio increased significantly from 125 ± 54 to 153 ± 73, and 163 ± 78 Torr. CHF patients did not reveal improvement of systolic, diastolic BP, and PF ratio after PMX‐DHP. Eight of ten patients in the untreated group died through exacerbated ARDS. In ARDS patients, PMX‐DHP improved circulatory disturbance and oxygenation despite the underlying diseases. The mortality improved compared with that before induction of PMX‐DHP. J. Clin. Apheresis 17:97–102, 2002. © 2002 Wiley‐Liss, Inc.
Alternative splicing during chondrogenesis: Modulation of fibronectin exon EIIIA splicing by SR proteins
Authors: Kuo Bruce A. , Uporova Tatiana M. , Liang Hongyan , Bennett Vickie D. , Tuan Rocky S. , Norton Pamela A.
Published: October 2002

The alternative exon EIIIA of the fibronectin gene is included in mRNAs produced in undifferentiated mesenchymal cells but excluded from differentiated chondrocytes. As members of the SR protein family of splicing factors have been demonstrated to be involved in the alternative splicing of other mRNAs, the role of SR proteins in chondrogenesis‐associated EIIIA splicing was investigated. SR proteins interacted with chick exon EIIIA sequences that are required for exon inclusion in a gel mobility shift assay. Addition of SR proteins to in vitro splicing reactions increased the rate and extent of exon EIIIA inclusion. Co‐transfection studies employing cDNAs encoding individual SR proteins revealed that SRp20 decreased mRNA accumulation in HeLa cells, which make A+ mRNA, apparently by interfering with pre‐mRNA splicing. Co‐transfection studies also demonstrated that SRp40 increased exon EIIIA inclusion in chondrocytes, but not in HeLa cells, suggesting the importance of cellular context for SR protein activity. Immunoblot analysis did not reveal a relative depletion of SRp40 in chondrocytic cells. Possible mechanisms for regulation of EIIIA splicing in particular, and chondrogenesis associated splicing in general, are discussed. J. Cell. Biochem. 86: 45–55, 2002. © 2002 Wiley‐Liss, Inc.
Sam68 associates with the SH3 domains of Grb2 recruiting GAP to the Grb2‐SOS complex in insulin receptor signaling
Authors: Najib Souad , Sánchez‐Margalet Víctor
Published: October 2002

The 68 kDa Src substrate associated during mitosis (Sam68) is an RNA binding protein with Src homology (SH) 2 and 3 domain binding sites. We have recently found that Sam68 is a substrate of the insulin receptor (IR) that translocates from the nucleus to the cytoplasm and that Tyr‐phosphorylated Sam68 associates with the SH2 domains of p85 PI3K and GAP, in vivo and in vitro. In the present work, we have further demonstrated the cytoplasmic localization of Sam68, which is increased in cells overexpressing IR. Besides, we sought to further study the association of Sam68 with the Ras‐GAP pathway by assessing the interactions with SH3 domains of Grb2. We employed GST‐fusion proteins containing the SH3 domains of Grb2 (N or C), and recombinant Sam68 for in vitro studies. In vivo studies of protein–protein interaction were assessed by co‐immunoprecipitation experiments with specific antibodies against Sam68, GAP, Grb2, SOS, and phosphotyrosine; and by affinity precipitation with the fusion proteins (SH3‐Grb2). Insulin stimulation of HTC‐IR cells promotes phosphorylation of Sam68 and its association with the SH2 domains of GAP. Sam68 is constitutively associated with the SH3 domains of Grb2 and it does not change upon insulin stimulation, but Sam68 is Tyr‐phosphorylated and promotes the association of GAP with the Grb2‐SOS complex. In vitro studies with fusion proteins showed that Sam68 association with Grb2 is preferentially mediated by the C‐terminal SH3 domains of Grb2. In conclusion, Sam68 is a substrate of the IR and may have a role as a docking protein in IR signaling, recruiting GAP to the Grb2‐SOS complex, and in this way it may modulate Ras activity. J. Cell. Biochem. 86: 99–106, 2002. © 2002 Wiley‐Liss, Inc.
Chronic pulsatile shear stress impacts synthesis of proteoglycans by endothelial cells: Effect on platelet aggregation and coagulation
Authors: Elhadj Selim , Mousa Shaker A. , Forsten‐Williams Kimberly
Published: October 2002

Endothelial‐derived proteoglycans are important regulators of the coagulation‐pathway in vivo and our primary objective of this study was to determine whether chronic shear stress affected the synthesis, release, and activity of proteoglycans from bovine aortic endothelial cells (BAEC). BAEC were cultured under shear and proteoglycans were purified from BAEC conditioned media and analyzed using both anionic exchange and size exclusion chromatography. The overall amount of proteoglycans produced per cell was significantly greater for the high shear‐treated samples compared to the low shear‐treated samples indicating that the shear magnitude did impact cell responsiveness. While overall size and composition of the proteoglycans and glycosaminoglycan (GAG) side chains were not altered by shear, the relative proportion of the high and low molecular weight species was inversely related to shear and differed significantly from that found under static tissue culture conditions. Moreover, a unique proteoglycan peak was identified from low shear stress (5 ± 2 dynes/cm2) conditioned media when compared to high shear conditions (23 ± 8 dynes/cm2) via anionic exchange chromatography, suggesting that subtle changes in the GAG structures may impact activity of these molecules. In order to characterize whether these changes impacted proteoglycan function, we studied the effects of shear specific proteoglycans on the inhibition of thrombin‐induced human platelet aggregation as well as on platelet‐fibrin clot dynamics. Proteoglycans from high shear‐treated samples were less effective inhibitors of both platelet aggregation and blood coagulation inhibition than proteoglycans from low shear‐treated samples and both were less effective than proteoglycans isolated from static tissue culture samples. However, due to changes in the overall proteoglycan synthesis and release rate, the high and low shear‐treated sample had essentially identical effects on these activities, suggesting that the cells were able to compensate for stress‐induced proteoglycan changes. Our data suggests that shear stress, by altering proteoglycan synthesis and fine structure, may play a role in maintaining vascular hemodynamics and hemostasis. © 2002 Wiley‐Liss, Inc.
Helix 12 in the human estrogen receptor (hER) is essential for the hER function by overcoming nucleosome repression in yeast
Authors: Gu Xiaohong
Published: October 2002

When exogenous human estrogen receptor (hER) binds with estrogen, it can activate transcription of target genes in yeast cells. The estrogen dose‐response expression patterns in yeast are very similar to those in human cells. This implies that hER may function in yeast cells via mechanisms similar to those in human cells. In this study, Saccharomyces cerevisiae was used to dissect mechanisms of hER‐activated transcription in yeast. The hER contains two transcription activation domains: ER‐AF‐1 and ER‐AF‐2 (LBD or HBD). In both human and wild‐type yeast cells, hER must bind with estrogen in order to activate transcription. In those cells, ER‐AF‐2 is independently active upon hormone binding, but ER‐AF‐1 by itself is inactive. In a mutagenesis screen, we found a mutant strain in which the ER‐AF‐1 was independently active. It was determined that this mutant strain carried a Tup1 mutation. More interestingly, a small hER fragment ER‐AF‐0, containing neither ER‐AF‐1 nor ER‐AF‐2, was also fully active in the ΔTup1 cells. This suggests that in this strain, hormone binding is not required for transcription activation by hER. It is known that the Tup1/Ssn6 complex plays an important role in general transcription repression by protecting histone acetylation sites thus stabilizing nucleosomes. In the ΔTup1 cells, nucleosomes are known to be unstable because histones can be easily accessed by acetylase and cause nucleosome disassociation. Two point mutations in helix 12 (H12) in ER‐AF‐2, which abolished hER function in human cells, also completely abolished hER function in the wild‐type yeast cells. This suggested that H12 is essential for hER transcription activation function. However, hER with the H12 mutation is able to activate transcription in ΔTup1 cells. This indicates that the normal function of H12 is required for transcription activation by hER only if nucleosomes are not acetylated and are therefore stable. The results of this work suggest that there is a close relationship between hER function and nucleosome remodeling. It also provides insight about H12 activity and its functional relationship with other domains in hER. We propose here that H12 is essential for hER function by recruiting strong nucleosome remodeling proteins to the promoter region thus overcoming nucleosome repression. J. Cell. Biochem. 86: 224–238, 2002. © 2002 Wiley‐Liss, Inc.
Nitric oxide and prostaglandin E2 participate in lipopolysaccharide/interferon‐γ‐induced heme oxygenase 1 and prevent RAW264.7 macrophages from UV‐irradiation‐induced cell death
Authors: Chen Yen‐Chou , Shen Shing‐Chuan , Lee Woan‐Ruoh , Lin Hui‐Yi , Ko Ching‐Huai , Lee Tony J.F.
Published: October 2002

Induction of heme oxygenase (HO)‐1 during inflammation has been demonstrated in many cell types, but the contribution of inflammatory molecules nitric oxide (NO) and prostaglandin E2 (PGE2) has remained unresolved. Here we show that NO donors including sodium nitroprusside (SNP) and spermine nonoate (SP‐NO), and PGE2 significantly stimulate HO‐1 expression in RAW264.7 macrophages, associated with alternative induction on NO and PGE2 in medium, respectively. NO donors also show the inductive effect on cyclo‐oxygenase 2 protein and PGE2 production. In the presence of lipopolysaccharide and interferon‐γ (LPS/IFN‐γ), HO‐1 protein was induced slightly but significantly, and SNP, SP‐NO, and PGE2 enhanced HO‐1 protein induced by LPS/IFN‐γ. L‐Arginine analogs N‐nitro‐L‐arginine methyl ester (L‐NAME) and N‐nitro‐L‐arginine (NLA) significantly block HO‐1 protein induced by LPS/IFN‐γ associated with a decrease in NO (not PGE2) production. And, NSAIDs aspirin and diclofenase dose dependently inhibited LPS/IFN‐γ‐induced HO‐1 protein accompanied by suppression of PGE2 (not NO) production. PD98059 (a specific inhibitor of MEKK), but not SB203580 (a specific inhibitor of p38 kinase), attenuated PGE2 (not SP‐NO) induced HO‐1 protein. Under UVC (100 J/m2) and UVB (50 J/m2) irradiation, PGE2 or SP‐NO treatment prevents cells from UVC or UVB‐induced cell death, and HO‐1 inhibitor tin protoporphyrin (SnPP) reverses the preventive effects of PGE2 and SP‐NO. The protective activity induced by PGE2 on UVC or UVB irradiation‐induced cell death was blocked by MAPK inhibitor PD98059 (not SB203580). These results demonstrated that inflammatory molecules NO and PGE2 were potent inducers of HO‐1 gene, and protected cells from UV‐irradiation‐induced cell death through HO‐1 induction. J. Cell. Biochem. 86: 331–339, 2002. © 2002 Wiley‐Liss, Inc.
Systemically administered rhBMP‐2 promotes MSC activity and reverses bone and cartilage loss in osteopenic mice
Authors: Turgeman Gadi , Zilberman Yoram , Zhou Shuanhu , Kelly Pam , Moutsatsos Ioannis K. , Kharode Yogendra P. , Borella Luis E. , Bex Frederick J. , Komm Barry S. , Bodine Peter V.N. , Gazit Dan
Published: October 2002

Osteoporosis is a disease manifested in drastic bone loss resulting in osteopenia and high risk for fractures. This disease is generally divided into two subtypes. The first, post‐menopausal (type I) osteoporosis, is primarily related to estrogen deficiency. The second, senile (type II) osteoporosis, is mostly related to aging. Decreased bone formation, as well as increased bone resorption and turnover, are thought to play roles in the pathophysiology of both types of osteoporosis. In this study, we demonstrate in murine models for both type I (estrogen deficiency) and type II (senile) osteopenia/osteoporosis that reduced bone formation is related to a decrease in adult mesenchymal stem cell (AMSC) number, osteogenic activity, and proliferation. Decreased proliferation is coupled with increased apoptosis in AMSC cultures obtained from osteopenic mice. Recombinant human bone morphogenetic protein (rhBMP‐2) is a highly osteoinductive protein, promoting osteogenic differentiation of AMSCs. Systemic intra‐peritoneal (i.p.) injections of rhBMP‐2 into osteopenic mice were able to reverse this phenotype in the bones of these animals. Moreover, this change in bone mass was coupled to an increase in AMSCs numbers, osteogenic activity, and proliferation as well as a decrease in apoptosis. Bone formation activity was increased as well. However, the magnitude of this response to rhBMP‐2 varied among different stains of mice. In old osteopenic BALB/c male mice (type II osteoporosis model), rhBMP‐2 systemic treatment also restored both articular and epiphyseal cartilage width to the levels seen in young mice. In summary, our study shows that AMSCs are a good target for systemically active anabolic compounds like rhBMP‐2. J. Cell. Biochem. 86: 461–474, 2002. © 2002 Wiley‐Liss, Inc.
Effects of alpha lipoic acid, ascorbic acid‐6‐palmitate, and fish oil on the glutathione, malonaldehyde, and fatty acids levels in erythrocytes of streptozotocin induced diabetic male rats
Authors: Yilmaz Ökkeş , Özkan Yusuf , Yildirim Mehmet , Öztürk A. İhsan , Erşan Yasemin
Published: October 2002

In this research, it has been aimed to evaluate the improvement effects of alpha lipoic acid (ALA), ascorbic acid‐6‐palmitate (AA6P), fish oil (FO), and their combination (COM) on some biochemical properties in erythrocytes of streptozotocin (STZ)‐induced diabetic male rats. According to experimental results, glutathione (GSH) level in erythrocytes decreased in diabetes (P < 0.01), D + ALA, and D + AA6P groups (P < 0.001). Malonaldehyde (MA) level increased in diabetes (P < 0.05), D + FO, and D + COM groups (P < 0.001), but its level in D + AA6P and D + ALA groups was lower in diabetes group (P < 0.01). Total lipid level in diabetes and diabetes plus antioxidant administered groups were higher than control. Total cholesterol level was high in diabetes and D + ALA groups (P < 0.05), but its level reduced in D + FO compared to control and diabetes groups, P < 0.05, < 0.001, respectively. Total triglyceride (TTG) level was high in the D + ALA (P < 0.05) and D + COM (P < 0.001) groups. In contrast, TTG level in blood of diabetes group was higher than diabetes plus antioxidant and FO administered groups (P < 0.001). According to gas chromatography analysis results, while the palmitic acid raised in diabetes group (P < 0.05), stearic acid in D + FO, D + ALA, and diabetes groups was lower than control (P < 0.05), oleic acid reduced in D + COM and D + FO groups, but its level raised in D + AA6P and D + ALA groups (P < 0.01). As the linoleic acid (LA) elevated in ALA + D, D + AA6P, and diabetes groups, linolenic acid level in diabetes, D + AA6P, and D + FO groups was lower than control (P < 0.001). Arachidonic acid (AA) decreased in D + ALA, D+ AA6P, and diabetes groups (P < 0.01), but its level in D + COM and D + FO was higher than control (P < 0.05). Docosahexaenoic acid (DHA) increased in D + AA6P and D + COM (P < 0.05). While the total saturated fatty acid level raised in diabetes group, its level reduced in D + ALA and D + FO groups (P < 0.05). In contrast, total unsaturated fatty acid level in D + ALA and D + FO groups was higher than control (P < 0.05). In conclusion, present data have confirmed that the combination of the ALA, AA6P, and FO have improvement effects on the recycling of GSSG to reduced GSH in erythrocytes of diabetic rats, and in addition to this, oxidative stress was suppressed by ALA and AA6P, and unsaturated fatty acid degree was raised by the effects of ALA and FO. J. Cell. Biochem. 86: 530–539, 2002. © 2002 Wiley‐Liss, Inc.
Differential nuclear receptor signalling from DR4‐type response elements
Authors: Quack Marcus , Frank Christian , Carlberg Carsten
Published: October 2002

Nuclear receptors form a large family of highly related transcription factors that transform an incoming signal in the form of a lipophilic hormone into an activation of the basal transcriptional machinery. The specific recognition of nuclear receptor DNA binding sites, referred to as response elements (REs), determines the genes that can be regulated by nuclear hormones. In this study, it was shown that the complexes of the retinoid X receptor (RXR) with either the vitamin D3 receptor (VDR), the thyroid hormone receptor (T3R) or the liver X receptor (LXR) have comparable functionality on a RE of the rat pit‐1 gene that is formed by a direct repeat of two hexameric binding motifs spaced by 4 nucleotides (DR4). The sequence of two nucleotides 5′‐flanking the downstream binding motif of this DR4‐type RE and, interestingly, also those flanking the upstream motif were shown to have in part rather drastic and receptor‐specific effects on heterodimer complex formation on DNA. In particular, a downstream substitution into GA reduced the complex formation for LXR specifically, while upstream substitutions into AA or TA increase complex formation for LXR and, to a lesser extent, T3R. The preference of this in vitro complex formation was shown to correlate well with the functional activity of the nuclear receptors in living cells. The results of this study allow (i) a more detailed understanding of known REs, (ii) a more straightforward search for putative REs in newly identified promoter sequences, for example, of the whole human genome, and (iii) a more precise prediction of the hormone responsiveness of the respective genes. J. Cell. Biochem. 86: 601–612, 2002. © 2002 Wiley‐Liss, Inc.
Role of nuclear PKC δ in mediating caspase‐3‐upregulation in Jurkat T leukemic cells exposed to ionizing radiation
Authors: Cataldi Amelia , Miscia Sebastiano , Centurione Lucia , Rapino Monica , Bosco Domenico , Grifone Giovanna , Valerio Valentina Di , Garaci Francesco , Rana Rosalba
Published: October 2002

The response of Jurkat T cells to ionizing radiation (IR) includes cell cycle arrest and DNA damage, which lead to the occurrence of apoptosis. Here, we try to elucidate some of the early intracellular signals which control the induction of such a process upon IR exposure, addressing to examine the specific role of several PKC isoforms (δ, ε, ζ) and their subcellular distribution. Attention has been focused on the connections between nuclear PKC δ activation and the expression of cell death regulators (Bcl‐2 family proteins Bad, Bax and Bcl‐2) and cell death effector caspase‐3 (CPP32) which lead to the cleavage of cytoskeletal and nuclear proteins and induction of apoptosis. Altogether these results let us to conclude that PKC δ, potentiating the pro‐apoptotic effect of caspase 3, plays a key role in the cellular response to IR and thus can be considered a molecular target for therapy. © 2002 Wiley‐Liss, Inc.
MT1‐MMP, but not secreted MMPs, influences the migration of human microvascular endothelial cells in 3‐dimensional collagen gels
Authors: Koike Teruhiko , Vernon Robert B. , Hamner Margaret A. , Sadoun Eman , Reed May J.
Published: October 2002

Matrix metalloproteinases (MMPs) and their specific inhibitors the TIMPs play significant roles in angiogenesis. We investigated how the expression of specific MMPs and TIMPs by human microvascular endothelial cells (hmECs) was modulated by culture of the cells in 3‐dimensional (3D) type I collagen gels versus 2‐dimensional (2D) collagen‐coated surfaces. By reverse‐transcription polymerase chain reaction (RT‐PCR), levels of mRNA for MMPs‐1, ‐2, and ‐13, MT1‐MMP, and TIMPs‐1 and ‐2 were similar in 2D versus 3D cultures. By Western blot assay, TIMP‐1 and proMMP‐1 were present and were expressed similarly in media from 2D versus 3D cultures, whereas active MMPs‐1, ‐9, and ‐13 were not detected. Active MMP‐13 was present in cell lysates (CL) and was increased in lysates from 3D cultures relative to 2D cultures. Relative to 2D cultures, CL and media from 3D cultures exhibited a decrease in expression of TIMP‐2 and an increased conversion of proMMP‐2 and proMT1‐MMP to active or processed forms. The MMP inhibitor GM6001 interfered with the migration of hmECs in 3D cultures, but not in 2D cultures. Addition of active MMP‐1 or blocking antibodies to TIMP‐1 did not affect the migration of hmECs in 3D collagen. Migration in 3D collagen was decreased by TIMP‐2 (an inhibitor of MT1‐MMP), but not by TIMP‐1 (a poor inhibitor of MT1‐MMP, but an efficient inhibitor of MMP‐2). Collectively, our data indicate that MT1‐MMP contributes significantly to the movement of hmECs through 3D collagen, in contrast to secretory‐type MMPs‐1, ‐2, ‐9, and ‐13, which are not critical for this movement. J. Cell. Biochem. 86: 748–758, 2002. © 2002 Wiley‐Liss, Inc.
Spectral density calculation by using the Chebyshev expansion
Authors: Ikegami Tsutomu , Iwata Suehiro
Published: October 2002

A method to calculate the spectral density of any state vectors with respect to a set of eigenstates of a Hamiltonian is presented. A spectral density operator, whose expectation value on the state vector gives the spectral density, is evaluated indirectly by using the Chebyshev expansion method. A spectral transformation function is introduced to improve resolution at the low energy region, at the expense of the one at the higher region. The predissociation spectrum of CO+ is calculated to demonstrate the method. © 2002 Wiley Periodicals, Inc. J Comput Chem 23: 310–318, 2002
Distance and exposure dependent effective dielectric function
Authors: Mallik Buddhadeb , Masunov Artem , Lazaridis Themis
Published: October 2002

In an effort to develop a dielectric screening function for molecular dynamics simulations of biomolecules in implicit solvent, effective dielectric constants (Deff) for a large number of atom pairs in a typical globular protein are calculated by continuum electrostatics. Plots of Deff versus the intercharge distance are in general sigmoidal with the characteristics of the curve depending on the distance of the two charges from the dielectric boundary and, secondarily, on the extent to which the area surrounding each charge is occupied by solvent (the “exposure”). The Deff values were fitted to an empirical, analytical function of these parameters that reproduces the data reasonably well, although considerable scatter exists in the range of Deff from 30 to 80. In the system used for parameterization, the mean square deviation of electrostatic interaction energies with this function is 0.48 kcal/mol, compared to 1.45 for an analytical Generalized Born model and 1.52 for the linear distance‐dependent dielectric model. When tested in other proteins of varying size and compactness, the present function is superior to both of the above models, except for a fully unfolded polypeptide chain, where the Generalized Born model is superior. © 2002 Wiley Periodicals, Inc. J Comput Chem 11: 1090–1099, 2002
An analysis of the influence of insurance sponsorship on MMPI changes among patients with chronic pain
Authors: Fow Neil R. , Dorris Gregory , Sittig Michael , Smith‐Seemiller Laura
Published: October 2002

Pretreatment and posttreatment MMPI scores of 821 patients who completed a chronic pain program were submitted to a multivariate analysis of variance, examining the effects of age, gender, and insurance sponsorship. With the exception of scale 9, all clinical scales were significantly lower at posttreatment. Only the sponsorship variable was found to be a moderator variable for these treatment effects, with decreases on scales 1, 2, 3, and 0 attenuated in subjects with Worker's Compensation sponsorship compared to other sponsorship. Suggestions for further multivariate research with this population are discussed. © 2002 Wiley Periodicals, Inc. J Clin Psychol 58: 827–832, 2002.
Protective factors against substance use among Asian American youth: A test of the peer cluster theory
Authors: Kim Irene J. , Zane Nolan W. S. , Hong Sehee
Published: October 2002

Few viable theoretical models of risk and protective factors for adolescent substance use have been empirically tested on diverse populations. The purpose of this study was twofold. First, the cross‐cultural validity of Oetting and Beauvais' (1987) peer cluster theory was tested on a sample of Asian American youth. Second, the effect of youths' immigration experience on the relationship among the protective factors was examined. Results showed partial support for the validity of the peer cluster model for this sample. As hypothesized, the peer domain variable was significantly related to substance use, while the family domain variable served as a protective factor against substance use. However, the school domain variable did not have any direct or indirect effects on substance use. There were no significant differences in the path model when the sample was split according to youth immigrant status. Implications for substance use prevention are discussed. © 2002 Wiley Periodicals, Inc.
Does p53 affect organismal aging?
Authors: Donehower Lawrence A.
Published: October 2002

The p53 protein plays a critical role in the prevention of cancer. It responds to a variety of cellular stresses to induce either apoptosis, a transient cell cycle arrest, or a terminal cell cycle arrest called senescence. Senescence in cultured cells is associated with augmented p53 activity and abrogation of p53 activity may delay in vitro senescence. Increasing evidence suggests that p53 may also influence aspects of organismal aging. Several mutant mouse models that display alterations in longevity and aging‐related phenotypes have defects in genes that alter p53 signaling. Recently, my laboratory has developed and characterized a p53 mutant mouse line that appears to have an enhanced p53 response. These p53 mutants exhibit increased cancer resistance, yet have a shortened longevity and display a number of early aging‐associated phenotypes, suggesting a role for p53 in the aging process. The nature of the aging phenotypes observed in this p53 mutant line is consistent with a model in which aging is driven in part by a gradual depletion of stem cell functional capacity. © 2002 Wiley‐Liss, Inc.
Mitochondria, the killer organelles and their weapons
Authors: Ravagnan Luigi , Roumier Thomas , Kroemer Guido
Published: October 2002

Apoptosis is a cell‐autonomous mode of death that is activated to eradicate superfluous, damaged, mutated, or aged cells. In addition to their role as the cell's powerhouse, mitochondria play a central role in the control of apoptosis. Thus, numerous pro‐apoptotic molecules act on mitochondria and provoke the permeabilization of mitochondrial membranes. Soluble proteins contained in the mitochondrial intermembrane space are released through the outer membrane and participate in the organized destruction of the cell. Several among these lethal proteins can activate caspases, a class of cysteine proteases specifically activated in apoptosis, whereas others act in a caspase‐independent fashion, by acting as nucleases (e.g., endonuclease G), nuclease activators (e.g., apoptosis‐inducing factor), or serine proteases (e.g., Omi/HtrA2). In addition, mitochondria can generate reactive oxygen species, following uncoupling and/or inhibition of the respiratory chain. The diversity of mitochondrial factors participating in apoptosis emphasizes the central role of these organelles in apoptosis control and unravels novel mechanisms of cell death execution. © 2002 Wiley‐Liss, Inc.
Cystathionine β‐synthase is coordinately regulated with proliferation through a redox‐sensitive mechanism in cultured human cells and Saccharomyces cerevisiae
Authors: Maclean Kenneth N. , Janošík Miroslav , Kraus Eva , Kožich Viktor , Allen Robert H. , Raab Beverly K. , Kraus Jan P.
Published: October 2002

Cystathionine β‐synthase (CBS) catalyzes the condensation of serine with homocysteine to form cystathionine and occupies a crucial regulatory position between the methionine cycle and the biosynthesis of cysteine by transsulfuration. Analysis of CBS activity under a variety of growth conditions indicated that CBS is coordinately regulated with proliferation in both yeast and human cells. In batch cultures of Saccharomyces cerevisiae, maximal CBS activities were observed in the exponential phase of cells grown on glucose, while growth‐arrested cultures or those growing non‐fermentatively on ethanol or glycerol had ∼3‐fold less activity. CBS activity assays and Western blotting indicated that growth‐specific regulation of CBS is evolutionarily conserved in a range of human cell lines. CBS activity was found to be maximal during proliferation and was reduced two‐ to five‐fold when cells became quiescent at confluence. In cultured HepG2 cells, the human CBS gene is induced by serum and basic fibroblast growth factor and is downregulated, but not abolished, by contact inhibition, serum‐starvation, nutrient depletion, or the induction of differentiation. Consequently, for certain cell types, CBS may represent a novel marker of both differentiation and proliferation. The intracellular level of the CBS regulator compound, S‐adenosylmethionine, was found to reflect the proliferation status of both yeast and human cells, and as such, constitutes an additional mechanism for proliferation‐specific regulation of human CBS. Our data indicates that screening compounds for the ability to affect transsulfuration in cultured cell models must take proliferation status into account to avoid masking regulatory interactions that may be of significance in vivo. © 2002 Wiley‐Liss, Inc.
Recovery of cellular E‐cadherin precedes replenishment of estrogen receptor and estrogen‐dependent proliferation of breast cancer cells rescued from a death stimulus
Authors: Malaguti Claudia , Rossini Gian Paolo
Published: October 2002

Loss of estrogen‐responsiveness and impaired E‐cadherin expression/function has been linked to increased metastatic potential of breast cancer cells. In this study, we report that proliferation of breast cancer cells can resume following removal of a toxic stimulus causing severe impairment of cell adhesion and estrogen responsiveness. This type of response was induced by okadaic acid (OA) in MCF‐7 cells, and was accompanied by an almost complete block of DNA synthesis, loss of cell–cell contact and cell detachment from culture dishes, loss of estrogen receptor (ER), progesterone receptor (PR) and E‐cadherin, whereas only a weak, if any, inhibition of protein synthesis could be observed. These responses were detected in MCF‐7 cells after a 1‐day treatment with 50 nM OA, and could be reversed if OA‐treated cells were recovered in a culture medium devoid of the toxin, so that rescued cells resumed growth 8–12 days after replating. By pulse‐chase experiments, we found that protein synthesis was not significantly affected in rescued cells, whose DNA synthesis, instead, was almost completely blocked during the first days of MCF‐7 cell rescue from OA treatment. We also analyzed E‐cadherin, mitogen activated protein kinase isoforms ERK1 and ERK2, Bcl‐2 and BAX proteins during the rescue of MCF‐7 cells from OA‐induced cell death, and found that their expression followed temporally defined patterns. Cellular levels of E‐cadherin returned to control levels within the first days of the rescue, followed by ER, ERK1, and ERK2, and finally by Bcl‐2 and BAX proteins. Under our experimental conditions, restoration of cell adhesion did not require a functional ER system, but recovery of a normal ER pool accompanied resumption of estrogen‐dependent proliferation of OA‐treated MCF‐7 cells. © 2002 Wiley‐Liss, Inc.
Heparan sulfate depletion within pulmonary fibroblasts: Implications for elastogenesis and repair
Authors: Buczek‐Thomas Jo Ann , Chu Chia L. , Rich Celeste B. , Stone Phillip J. , Foster Judith A. , Nugent Matthew A.
Published: October 2002

We investigated the role of sulfated proteoglycans in regulating extracellular matrix (ECM) deposition in pulmonary fibroblast cultures. Fibroblast cultures were subject to pharmacologic and enzymatic interventions to modify sulfated proteoglycan levels. Native and proteoglycan‐depleted fibroblasts were treated with porcine pancreatic elastase at 2–4‐day intervals and the elastase‐mediated release of fibroblast growth factor 2 (FGF‐2) and glycosaminoglycans was determined. Elastase treatment released significantly less FGF‐2 and glycosaminoglycans (GAG) from PG‐depleted fibroblasts with respect to native cells. Equilibrium ligand binding studies indicated that 125I FGF‐2 binding at both cell surface receptor and heparan sulfate proteoglycan sites was reduced to different extents based on the method of proteoglycan depletion. Quantitation of elastin protein and message levels indicated that biological sulfation is required for the proper incorporation of tropoelastin into the extracellular matrix. These results suggest that sulfated proteoglycans play a central role in modulating pulmonary fibroblast extracellular matrix composition and are important mediators of elastolytic injury. © 2002 Wiley‐Liss, Inc.
Recent progress in the neurobiology of the vomeronasal organ
Authors: Takami Shigeru
Published: October 2002

In many terrestrial tetrapodes, a pair of vomeronasal organs (VNOs), which are chemosensory apparatuses, are situated at the base of the nasal septum in the anterior nasal cavity. The purposes of this review are to summarize comparative neuroanatomy and to introduce recent progress in neurobiological studies of the VNO. Five types of VNOs can be identifiable in terms of anatomical organization; snakes possess the most complex one. Sensory cells in the VNO, vomeronasal receptor neurons (VRNs), are located in its neuroepithelium, vomeronassal sensory epithelium. The VRNs retain the characteristic of epithelial cells in that they are born continuously from progenitor cells. They contain two prominent subcellular structures: microvilli and extraordinarily large amounts of smooth endoplasmic reticulum and a few unique glycoconjugates. The VRNs express two types of G‐protein ‐subunits: Giα2 and Goα and each of them is coupled with putative pheromone receptors, V1Rs and V2Rs, respectively. Recent physiological and biochemical studies have demonstrated that pheromones depolarize the V1R‐Giα2 and V2R‐Goα VRNs via IP3‐mediated mechanisms. The VRNs do not show adaptation and are ultrasensitive to putative pheromones. Other than being a chemosensory organ, the VNO and its primordium might play important roles for brain development; hypothalamic neurons that produce gonadotropin‐releasing hormone are born in the VNO primordium and a few other neuron‐like cells may be born in the VNO primordium and VNO. In human fetuses, anatomical findings strongly suggest that their VNOs contain a neuroepithelium. By contrast, it is unlikely that adult human VNO serves as a chemosensory organ. Microsc. Res. Tech. 58:228–250, 2002. © 2002 Wiley‐Liss, Inc.
Morphological aspects of particle uptake by lung phagocytes
Authors: Geiser Marianne
Published: October 2002

Macrophages residing on the inner epithelial surfaces of airways and alveoli are the only lung phagocytes exposed directly to the environment. Their phagocytic and microbicidal activities are essential for maintaining this organ in a clean and sterile state. The morphology of these phagocytes can be investigated in situ only after implementing special techniques, which involve intravascular triple‐perfusion of aqueous fixatives or instillation of nonpolar ones. Such studies have revealed the engulfment of particles by these cells to be rapid, the process being essentially complete within a day. Particles are entrapped within phagosomes and the host cells eventually transported out of the lungs by mucociliary action, macrophages with higher loads being more rapidly eliminated than those with lower ones. Very small particles or those persisting on the epithelial surfaces may be taken up by the eponymous cells. Translocation of particles into the underlying connective tissue and their subsequent phagocytosis by interstitial macrophages prolongs their retention time in the lungs. The still poorly studied pleural macrophages might be involved in cell‐mediated immune responses within the pleural space. Intravascular pulmonary macrophages figure largely in the phagocytosis of circulating particles. The role played by dendritic cells in particle uptake by the lungs is not well understood. Airway and alveolar macrophages are the primary phagocytes of the lung. In nonoverload situations and for particles >1 μm, a small proportion of those recruited suffices to remove material from the epithelial surface before other phagocytes, with an apparently greater immunological potential, gain access to it. Microsc. Res. Tech. 57:512–522, 2002. © 2002 Wiley‐Liss, Inc.
Behavior of graft and host cells in underlying subchondral bone after transplantation of osteochondral autograft
Authors: Oshima Yasushi , Watanabe Nobuyoshi , Matsuda Ken‐Ichi , Takenaka Nobuyuki , Kawata Mitsuhiro , Takai Shinro
Published: October 2002

Transplantation of osteochondral autograft is widely used as a therapeutic strategy for the defect of articular cartilage. In the repair process, although underlying subchondral bone becomes necrotic and then is followed by bone reconstruction, the fate of graft and host cells during remodeling of underlying subchondral bone has not been elucidated. The objectives of this study were to establish a method to follow graft and host cells after transplantation of osteochondral autograft, and to elucidate the fate of both graft and host cells during remodeling of underlying subchondral bone. For these purposes, autologous transplantation models employing transgenic rats and wild‐type rats, which were genetically identical to each other except for transgenes, were used. Two transplantation models were designed so that either the graft or the host cells had transgenes. Model I: transgenic rats were the donor, and wild‐type rats were the recipient; model II: conversely, wild‐type rats were the donor, and transgenic rats were the recipient. The grafted bone marrow cells and osteocytes in the trabeculae survived in the graft at 3 weeks after transplantation. Invasion of the host bone marrow cells into the graft was also found. Thus, bone marrow cells in the host as well as both bone marrow cells and osteocytes in the graft could potentially participate in the remodeling of underlying subchondral bone. Furthermore, the interface between graft and host was consisted with both graft and host derived cells. Since new bone formation was found in this space, both graft and host cells could have the potential to contribute to remodeling of underlying subchondral bone. The two models of the transplantations using the transgenic rats were found to be beneficial in following graft cells as well as host cells and in understanding their function on healing after autologous transplantation. Microsc. Res. Tech. 58:19–24, 2002. © 2002 Wiley‐Liss, Inc.
Response of donor and recipient cells after transplantation of cells to the ligament and tendon
Authors: Hildebrand Kevin A. , Jia Fengyan , Woo Savio L.‐Y.
Published: October 2002

The mechanical properties of healing ligaments and tendons are not comparable to those of normal tissue. To improve the quality of the ligament healing, therapeutic strategies include gene transfer or placement of mesenchymal stem cells at the healing site. Studies show that marker genes, growth factors, and antisense oligonucleotides can be delivered to both normal and healing ligaments and tendons by gene transfer. Cells with and without genetic modification have been successfully transplanted to ligaments and tendons and remain viable. Tendon healing can be improved using collagen gel implants seeded with autologous mesenchymal stem cells. Even though these early results are encouraging, more work is required regarding the response of the recipient site to donor cells or vectors. Microsc. Res. Tech. 58:34–38, 2002. © 2002 Wiley‐Liss, Inc.