bluuebunny/crossref_metadata_2025 huggingface dataset:
Defective insulin signaling in skeletal muscle of the hypertensive TG(mREN2)27 rat
Authors: Sloniger Julie A. , Saengsirisuwan Vitoon , Diehl Cody J. , Dokken Betsy B. , Lailerd Narissara , Lemieux Andrew M. , Kim John S. , Henriksen Erik J.
Published: January 2005

Essential hypertension is frequently associated with insulin resistance of skeletal muscle glucose transport, with a potential role of angiotensin II in the pathogenesis of both conditions. The male heterozygous TG(mREN2)27 rat harbors the mouse transgene for renin, exhibits local elevations in angiotensin II, and is an excellent model of both hypertension and insulin resistance. The present study was designed to investigate the potential cellular mechanisms for insulin resistance in this hypertensive animal model, including an assessment of elements of the insulin-signaling pathway. Compared with nontransgenic, normotensive Sprague-Dawley control rats, male heterozygous TG(mREN2)27 rats displayed elevated ( P < 0.05) fasting plasma insulin (74%), an exaggerated insulin response (108%) during an oral glucose tolerance test, and reduced whole body insulin sensitivity. TG(mREN2)27 rats also exhibited decreased insulin-mediated glucose transport and glycogen synthase activation in both the type IIb epitrochlearis (30 and 46%) and type I soleus (22 and 64%) muscles. Importantly, there were significant reductions (∼30–50%) in insulin stimulation of tyrosine phosphorylation of the insulin receptor β-subunit and insulin receptor substrate-1 (IRS-1), IRS-1 associated with the p85 subunit of phosphatidylinositol 3-kinase, Akt Ser473phosphorylation, and Ser9phosphorylation of glycogen synthase kinase-3β in epitrochlearis and soleus muscles of TG(mREN2)27 rats. Soleus muscle triglyceride concentration was 25% greater in the transgenic group compared with nontransgenic animals. Collectively, these data provide the first evidence that the insulin resistance of the hypertensive male heterozygous TG(mREN2)27 rat can be attributed to specific defects in the insulin-signaling pathway in skeletal muscle.
Calcium-sensing receptor activation induces nitric oxide production in H-500 Leydig cancer cells
Authors: Tfelt-Hansen Jacob , Ferreira Ana , Yano Shozo , Kanuparthi Deephti , Romero Jose R. , Brown Edward M. , Chattopadhyay Naibedya
Published: January 2005

Nitric oxide (NO) is a versatile second messenger. NO is produced by Leydig cells, where NO is a negative regulator of steroidogenesis. In cancer cells, NO is thought to have mutagenic and proliferative effects. We have previously shown that the calcium-sensing receptor (CaR) has promalignant effects in rat H-500 Leydig cancer cells, a model for humoral hypercalcemia of malignancy. Calcium, the major physiological ligand of the CaR, is a recognized intracellular cofactor in the process of NO production by virtue of its positive modulation of neuronal and endothelial nitric oxide synthase (NOS), but importantly, not of inducible (i) NOS activity. iNOS activity is regulated by changes in its expression level. Therefore, we investigated whether CaR activation changes iNOS expression. We found that high extracellular calcium (Ca[Formula: see text]) upregulates the level of mRNA for iNOS, whereas no change was seen in neuronal or endothelial NOS, as assessed by microarray and real-time PCR, respectively. The high Ca[Formula: see text]-induced iNOS upregulation was also detected by Northern and Western blotting. By quantitative real-time PCR, we showed that calcium maximally upregulates iNOS at 18 h. The effect of calcium was abolished by overexpression of a dominant-negative CaR (R185Q), confirming that the effect of Ca[Formula: see text] was mediated by the CaR. Cells treated with high calcium had higher NO production than those treated with low calcium, as detected with the NO-specific DAF2-AM dye. This was confirmed in single-cell fluorescence determinations using confocal microscopy. In conclusion, high calcium upregulates the levels of iNOS mRNA and protein as well as NO production in H-500 cells, and the effect of Ca[Formula: see text] on iNOS expression is mediated by the CaR.
Arginine synthesis does not occur during first-pass hepatic metabolism in the neonatal piglet
Authors: Urschel Kristine L. , Shoveller Anna K. , Pencharz Paul B. , Ball Ronald O.
Published: January 2005

We have shown that first-pass intestinal metabolism is necessary for ∼50% of whole body arginine synthesis from its major precursor proline in neonatal piglets. Furthermore, the intestine is not the site of increased arginine synthesis observed during dietary arginine deficiency. Primed constant intravenous (iv) and intraportal (ip) infusions of l-[U-14C]proline, and iv infusion of either l-[ guanido-14C]arginine or l-[4,5-3H]arginine were used to measure first-pass hepatic arginine synthesis in piglets enterally fed either deficient (0.20 g·kg−1·day−1) or generous (1.80 g·kg−1·day−1) quantities of arginine for 5 days. Conversion of arginine to other urea cycle intermediates and arginine recycling were also calculated for both dietary treatments. Arginine synthesis (g·kg−1·day−1) from proline was greater in piglets ( P < 0.05) fed the deficient arginine diet in both the presence (generous: 0.07; deficient: 0.17; pooled SE = 0.01) and absence (generous: 0.06; deficient: 0.20; pooled SE = 0.01) of first-pass hepatic metabolism. There was no net arginine synthesis from proline during first-pass hepatic metabolism regardless of arginine intake. Arginine conversion to urea, citrulline, and ornithine was significantly greater ( P < 0.05) in piglets fed the generous arginine diet. Calculated arginine fluxes were significantly lower ( P = 0.01) for [4,5-3H]arginine than for [ guanido-14C]arginine, and the discrepancy between the values was greater in piglets fed the deficient arginine diet (35% vs. 20%). Collectively, these findings show that first-pass hepatic metabolism is not a site of net arginine synthesis and that piglets conserve dietary arginine in times of deficiency by decreasing hydrolysis and increasing recycling.
Contraction- and hypoxia-stimulated glucose transport is mediated by a Ca2+-dependent mechanism in slow-twitch rat soleus muscle
Authors: Wright David C. , Geiger Paige C. , Holloszy John O. , Han Dong-Ho
Published: January 2005

Increases in contraction-stimulated glucose transport in fast-twitch rat epitrochlearis muscle are mediated by AMPK- and Ca2+/calmodulin-dependent protein kinase (CAMK)-dependent signaling pathways. However, recent studies provide evidence suggesting that contraction-stimulated glucose transport in slow-twitch skeletal muscle is mediated through an AMPK-independent pathway. The purpose of the present study was to test the hypothesis that contraction-stimulated glucose transport in rat slow-twitch soleus muscle is mediated by an AMPK-independent/Ca2+-dependent pathway. Caffeine, a sarcoplasmic reticulum (SR) Ca2+-releasing agent, at a concentration that does not cause muscle contractions or decreases in high-energy phosphates, led to an ∼2-fold increase in 2-deoxyglucose (2-DG) uptake in isolated split soleus muscles. This increase in glucose transport was prevented by the SR calcium channel blocker dantrolene and the CAMK inhibitor KN93. Conversely, 5-aminoimidazole-4-carboxamide-1-β-d-ribofuranoside (AICAR), an AMPK activator, had no effect on 2-DG uptake in isolated split soleus muscles yet resulted in an ∼2-fold increase in the phosphorylation of AMPK and its downstream substrate acetyl-CoA carboxylase. The hypoxia-induced increase in 2-DG uptake was prevented by dantrolene and KN93, whereas hypoxia-stimulated phosphorylation of AMPK was unaltered by these agents. Tetanic muscle contractions resulted in an ∼3.5-fold increase in 2-DG uptake that was prevented by KN93, which did not prevent AMPK phosphorylation. Taken in concert, our results provide evidence that hypoxia- and contraction-stimulated glucose transport is mediated entirely through a Ca2+-dependent mechanism in rat slow-twitch muscle.
A SAGE-based comparison between glomerular and aortic endothelial cells
Authors: Sengoelge Gürkan , Luo Wensheng , Fine Derek , Perschl Agnes M. , Fierlbeck Wolfgang , Haririan Abdolreza , Sorensson Jenny , Rehman Tausif-Ur , Hauser Peter , Trevick Jacob S. , Kulak Stephen C. , Wegner Binytha , Ballermann Barbara J.
Published: January 2005

Endothelial cells have many characteristics in common, but significant morphological and functional differences exist between endothelial cells from different anatomic sites. The specific glomerular endothelial (GEn) cell transcript repertoire is unknown. We sought to determine whether endothelial cells derived from bovine glomeruli display a distinct transcriptional profile compared with bovine aortic endothelium (BAE) under identical conditions. Serial analysis of gene expression (SAGE), which includes known and unknown transcripts, was used to make the comparison. The GEn and BAE SAGE libraries contain 36,844 and 26,452 total tag sequences, respectively. Among 6,524 unique tag sequences represented at least 2 times in the 2 libraries, 2,094 (32%) were matched to well-characterized bovine cDNA sequences (358 tags) or expressed sequence tags (EST). Identification of the human homolog was achieved for 1,035 of these tags. Forty-two tags were differentially expressed in GEn. For 25 of these, the bovine cDNA or EST, and for 17 the human homolog was identified. Among all transcripts with a known bovine and human tag, seven were expressed at levels more than 10-fold higher in cultured GEn cells compared with all other SAGE libraries. The transcript “DKFZp564B076” was localized by in situ hybridization to glomerular endothelium in vivo and was shown by real-time RT-PCR to be highly abundant in glomeruli compared with aortic intima. This work supports the concept that differences in the transcriptional profile of endothelial cells from distinct origins are observed under otherwise equivalent conditions. Furthermore, we have identified the first known transcript predominant in glomerular endothelium in vivo.
Interacting genetic loci cause airway hyperresponsiveness
Authors: Ackerman Kate G. , Huang Hailu , Grasemann Hartmut , Puma Chris , Singer Jonathan B. , Hill Annie E. , Lander Eric , Nadeau Joseph H. , Churchill Gary A. , Drazen Jeffrey M. , Beier David R.
Published: January 2005

Airway hyperresponsiveness (AHR) is a key physiological component of asthma, and the genetic basis of this complex trait has remained elusive. We created recombinant congenic mice with increased naive AHR by serially backcrossing A/J mice (which have elevated naive AHR) with C57BL/6J mice and selecting for mice with an elevated naive AHR phenotype. The seventh backcross-generation hyperresponsive mice retained A/J loci in three regions. Quantitative trait linkage (QTL) analysis of 123 unselected N8 progeny demonstrated that the AHR phenotype was not associated with any single locus but was significantly associated with an interaction of loci on chromosomes 2 and 6. These findings were confirmed in an independent analysis of chromosome substitution strain mice. The identification of genomic regions containing loci causally associated with AHR and the demonstration that this trait requires their interaction have important implications for the dissection of the genetic etiology of asthma in humans.
‘To the Other Side’: Construction of Evil and Fear of Liberation in Mark 5.1-20
Authors: Burdon Christopher
Published: January 2005

Narratives, like the establishment of identities, proceed by oppositions and the construction of what is ‘other’. In the present global situation, alertness to such constructions and their dangers is vital, especially when they derive from canonical texts. After an examination of the case for Mark’s Gospel as liberating story, the article analyses the construction of evil as foreignness in the story of the Gerasene demoniac and its subsequent subversion—first by the revelation of the demons’ name and its political reference, then by the local people’s rejection of Jesus, and finally by the healed man’s proclamation. Jesus’ crossing ‘to the other side’ is seen as a paradigm of his own and the implied readers’ continuing transition to engagement with the Other.
‘The Commandment which is for Life’ (Romans 7.10): Sin’s Use of the Obedience of Faith
Authors: Jervis L. Ann
Published: January 2005

Chapter 7 of Romans has been the focus of a vigorous debate over whether Paul’s discourse is focused on the pre-Christ or the post-Christ experience. This discussion has not extended to the interpretation of 7.9-11, however. Scholars on both sides of the debate appeal to Gen. 2 and 3 to explain these verses. At the same time, despite the fact that the Genesis story takes place well before the giving of Torah, scholars understand the ‘commandment’ to which Paul refers in these verses as a commandment of Torah. This convoluted but common reading is here called into question and a new proposal advanced: the commandment to which Paul refers in Rom 7.9-12 is the commandment inherent to life in Christ.
Condom Use Predictors for Low-Income African American Women
Authors: Dancy Barbara L. , Berbaum Michael L.
Published: January 2005

The purpose was to investigate whether an HIV-prevention curriculum and a health maintenance curriculum produced different rates of change in reported consistent condom use and to explore what mediating variables predicted reported consistent condom use over time. A longitudinal crossover research design with extended posttest observations was used with a sample of 279 African American women. After pretesting, women received the designated curriculum and were posttested at completion, 3, 6, and 9 months. After the 9-month posttest, the curriculum was switched, and the above procedure was repeated. Using SAS macro GLIMMIX, the data revealed that the HIV curriculum yielded higher consistent condom use than did the health maintenance curriculum and that the mediating variables that predicted consistent condomuse over time were self-efficacy for low-risk HIV behavior, HIV-related community behavior, and social norms. Enhancing consistent condom use over time may require the promotion and reinforcement of these mediating variables.
Who are the Princes of Persia and Greece (Daniel 10)? Pointers Towards the Danielic Vision of Earth and Heaven
Authors: Meadowcroft Tim
Published: January 2005

An examination of the nature of the ‘princes’ of Persia and Greece in Daniel 10 suggests that these figures could just as easily be the temporal leaders of those kingdoms as angelic or heavenly figures of some sort. This is indicative of an apocalyptic cosmology of permeability between earth and heaven that has not always been well appreciated. This conclusion is supported by a number of features of the narratives in chs. 7-9 and also chs. 10-12. It is also in tune with the nature of the book of Daniel as a whole, with its juxtaposition of court tales and heavenly visions. The significance of this for contemporary missiology and theology, as well as pastoral practice, is explored in an Appendix to the article
Extending Point-sensor Performance by Incorporating Distributed-sensors and Window Functions
Authors: Hsu Yu-Hsiang , Lee Chih-Kung
Published: January 2005

By integrating the methodologies of window functions and the method of image, the performance of the traditional piezoelectric point and distributed sensors, such as accelerometers, can be tailored by modifying their transfer functions in the spatial domain. The approach used in extending the sensor performance consists of developing a series of methodologies that can tailor the gain of the sensor transfer function while keeping the phase of the sensor transfer function intact. We can show that these spatially introduced design methodologies bypass the Bode gain-phase theorem, which states that gain and phase are interrelated for all minimum phase systems. The effects of adopting these sensors to flexible structure control and point sensors are examined in detail. It can also be shown that a series of low-pass filters, which exerts autonomous behavior between the gain and the phase of the sensor transfer function, can be introduced to significantly influence the performance of the sensing or controlling loops that incorporates these sensors. In addition, variables such as the power of the window functions adopted, the desired corner frequency, the length of the sensor structure, etc., all can be shown to have a decisive impact on the performance of the newly invented sensors. Both theoretical and experimental results of the underlying principles, design methodologies, and implementation process of these newly invented sensors are detailed.
Contraception and Heterosex: An Intimate Relationship
Authors: Lowe Pam
Published: January 2005

Whilst the importance of contraception within heterosex has long been accepted, particularly in relation to the prevention of HIV/AIDS, the way in which the use, or non-use, of contraception re/constructs heterosexual encounters themselves has had far less attention. The embodied nature of both the risk of pregnancy, and most contraceptive technologies leads women to assert a right to bodily autonomy. Yet this assertion conflicts with their expectation of equitable coupledom within heterosexuality and their routine consideration of men’s preferences. This article will argue that the use of contraception is an intricate part of heterosexual practices, and shows how normative ideas about heterosexuality leave men as appearing as an absent presence within women’s contraceptive decisions.
The magnitude and breadth of hepatitis C virus–specific CD8+ T cells depend on absolute CD4+ T-cell count in individuals coinfected with HIV-1
Authors: Kim Arthur Y. , Lauer Georg M. , Ouchi Kei , Addo Marylyn M. , Lucas Michaela , Wiesch Julian Schulze zur , Timm Joerg , Boczanowski Melinda , Duncan Jared E. , Wurcel Alysse G. , Casson Deborah , Chung Raymond T. , Draenert Rika , Klenerman Paul , Walker Bruce D.
Published: January 2005

CD8+ T-cell responses are an essential antiviral host defense in persistent viral infections, and their sustained effectiveness is thought to be critically dependent on CD4+ T-helper cells. To determine the relationship between HIV-1–induced CD4+ T-cell depletion and hepatitis C virus (HCV)–specific CD8+ T-cell responses during viral persistence, we studied 103 persons positive for HCV, 74 coinfected with HIV-1. CD8+ T-cell responses to the entire HCV polyprotein were determined by using an interferon-γ enzyme-linked immunospot (ELISpot) assay. Although HIV-1 infection by itself was not associated with a diminished HCV-specific response, HIV-1–associated CD4+ depletion was associated with significantly lower HCV-specific CD8+ T cells (R = 0.48, P < .0001). In contrast, declining CD4+ counts over the same range were not associated with diminished Epstein-Barr virus (EBV)– (R = 0.19, P = .31) or HIV-1–specific (R = –0.13, P = .60) CD8+ T-cell responses in persons infected with all viruses. These data indicate that frequencies of circulating HCV-specific CD8+ T-cell responses are sensitive to absolute CD4+ T-cell counts and provide a possible explanation for the accelerated HCV disease course in persons coinfected with HIV-1 and HCV.
Cross-recognition of human alloantigen by cytomegalovirus glycoprotein-specific CD4+ cytotoxic T lymphocytes: implications for graft-versus-host disease
Authors: Elkington Rebecca , Khanna Rajiv
Published: January 2005

Presence of the HLA-DR7 allele in patients who receive transplants has been proposed as a risk factor for human cytomegalovirus (HCMV)–associated complications; however, the precise mechanism of this increased risk remains unresolved. Here we show that HLA-DR7–restricted HCMV-specific CD4+ cytotoxic T lymphocytes (CTLs) can display an unusual dual specificity toward a glycoprotein-B (gB) epitope and the alloantigen HLA-DR4. However, no HLA-DR4–specific alloreactivity was observed when the gB-specific CTLs were generated from virus carriers expressing both HLA-DR7 and DR4 alleles. This most likely demonstrates the clonal inactivation of potentially self-reactive T cells in humans. Fine specificity analysis showed that gB-specific CTLs from HLA-DR7+/DR4- individuals displayed a distinct pattern of recognition when compared with CTLs from HLA-DR7+/DR4+ individuals, presumably evading an area of the epitope that mimics a structure presented on HLA-DR4. These data illustrate a possible mechanism for the clinical association between HCMV and graft-versus-host disease.
Identification of a human mutation of DMT1 in a patient with microcytic anemia and iron overload
Authors: Mims Martha P. , Guan Yongli , Pospisilova Dagmar , Priwitzerova Monika , Indrak Karel , Ponka Prem , Divoky Vladimir , Prchal Josef T.
Published: January 2005

Divalent metal transporter 1 (DMT1) is a transmembrane protein crucial for duodenal iron absorption and erythroid iron transport. DMT1 function has been elucidated largely in studies of the mk mouse and the Belgrade rat, which have an identical single nucleotide mutation of this gene that affects protein processing, stability, and function. These animals exhibit hypochromic microcytic anemia due to impaired intestinal iron absorption, and defective iron utilization in red cell precursors. We report here the first human mutation of DMT1 identified in a female with severe hypochromic microcytic anemia and iron overload. This homozygous mutation in the ultimate nucleotide of exon 12 codes for a conservative E399D amino acid substitution; however, its pre-dominant effect is preferential skipping of exon 12 during processing of pre–messenger RNA (mRNA). The lack of full-length mRNA would predict deficient iron absorption in the intestine and deficient iron utilization in erythroid precursors; however, unlike the animal models of DMT1 mutation, the patient is iron overloaded. This does not appear to be due to up-regulation of total DMT1 mRNA. DMT1 protein is easily detectable by immunoblotting in the patient's duodenum, but it is unclear whether the protein is properly processed or targeted.
The effect of first-line imatinib interim therapy on the outcome of allogeneic stem cell transplantation in adults with newly diagnosed Philadelphia chromosome–positive acute lymphoblastic leukemia
Authors: Lee Seok , Kim Yoo-Jin , Min Chang-Ki , Kim Hee-Je , Eom Ki-Sung , Kim Dong-Wook , Lee Jong-Wook , Min Woo-Sung , Kim Chun-Choo
Published: January 2005

Previously, we suggested that imatinib incorporation into conventional chemotherapy as an alternative (imatinib interim therapy) might be a useful strategy for bridging the time to allogeneic stem cell transplantation (SCT) for newly diagnosed Philadelphia chromosome–positive acute lymphoblastic leukemia (Ph+ ALL). Here, we provide an updated report on this strategy in 29 patients. At the time of enrollment, 23 patients (79.3%) achieved complete remission (CR). After the first imatinib cycle, the median breakpoint cluster region–Abelson oncogene locus (BCR-ABL)/ABL ratios decreased by 0.77 log in 25 (86.2%) responders, and their BCR-ABL/ABL ratios decreased further by 0.34 log after the second imatinib cycle, which included 7 molecular CR. One patient (4.3%) relapsed during the imatinib therapy. The remaining 3 patients were primarily refractory to both imatinib and chemotherapy. Twenty-five (86.2%) of the 29 patients received transplants in first CR. With a median follow-up duration of 25 months after SCT, the 3-year estimated probabilities of relapse, nonrelapse mortality, disease-free survival, and overall survival were 3.8%, 18.7%, 78.1%, and 78.1%, respectively. In comparison to our historical control data, first-line imatinib interim therapy appears to provide a good quality of CR and a survival advantage for patients with Ph+ ALL. Further long-term follow-up is needed to validate the results of this study.
Modelling the correlation between the activities of adjacent genes in drosophila
Authors: Thygesen Helene H , Zwinderman Aeilko H
Published: January 2005

Background

Correlation between the expression levels of genes which are located close to each other on the genome has been found in various organisms, including yeast, drosophila and humans. Since such a correlation could be explained by several biochemical, evolutionary, genetic and technological factors, there is a need for statistical models that correspond to specific biological models for the correlation structure.

Results

We modelled the pairwise correlation between the expressions of the genes in a Drosophila microarray experiment as a normal mixture under Fisher's z-transform, and fitted the model to the correlations of expressions of adjacent as well as non-adjacent genes. We also analyzed simulated data for comparison. The model provided a good fit to the data. Further, correlation between the activities of two genes could, in most cases, be attributed to either of two factors: the two genes both being active in the same age group (adult or embryo), or the two genes being in proximity of each other on the chromosome. The interaction between these two factors was weak.

Conclusions

Correlation between the activities of adjacent genes is higher than between non-adjacent genes. In the data we analyzed, this appeared, for the most part, to be a constant effect that applied to all pairs of adjacent genes.
Genome-scale analysis of positional clustering of mouse testis-specific genes
Authors: Li Quan , Lee Bernett TK , Zhang Louxin
Published: January 2005

Background

Genes are not randomly distributed on a chromosome as they were thought even after removal of tandem repeats. The positional clustering of co-expressed genes is known in prokaryotes and recently reported in several eukaryotic organisms such as Caenorhabditis elegans, Drosophila melanogaster, and Homo sapiens. In order to further investigate the mode of tissue-specific gene clustering in higher eukaryotes, we have performed a genome-scale analysis of positional clustering of the mouse testis-specific genes.

Results

Our computational analysis shows that a large proportion of testis-specific genes are clustered in groups of 2 to 5 genes in the mouse genome. The number of clusters is much higher than expected by chance even after removal of tandem repeats.

Conclusion

Our result suggests that testis-specific genes tend to cluster on the mouse chromosomes. This provides another piece of evidence for the hypothesis that clusters of tissue-specific genes do exist.
Upregulated expression of human neutrophil peptides 1, 2 and 3 (HNP 1-3) in colon cancer serum and tumours: a biomarker study
Authors: Albrethsen Jakob , Bøgebo Rikke , Gammeltoft Steen , Olsen Jesper , Winther Benny , Raskov Hans
Published: January 2005

Background

Molecular markers for localized colon tumours and for prognosis following therapy are needed. Proteomics research is currently producing numerous biomarker studies with clinical potential. We investigate the protein composition of plasma and of tumour extracts with the aim of identifying biomarkers for colon cancer.

Methods

By Surface Enhanced Laser Desorption/Ionisation – Time Of Flight / Mass spectrometry (SELDI-TOF/MS) we compare the protein profiles of colon cancer serum with serum from healthy individuals and the protein profiles of colon tumours with normal colon tissue. By size exclusion chromatography, we investigate the binding of HNP 1-3 to high mass plasma proteins. By microflow we investigate the effect of HNP 1-3 on mammalian cells.

Results

Human Neutrophil Peptides -1, -2 and -3 (HNP 1-3), also known as alfa-defensin-1, -2 and -3, are present in elevated concentrations in serum from colon cancer patients and in protein extracts from colon tumours. A fraction of HNP 1-3 in serum is bound to unidentified high mass plasma proteins. HNP 1-3 purified from colon tumours are lethal to mammalian cells.

Conclusions

HNP 1-3 may serve as blood markers for colon cancer in combination with other diagnostic tools. We propose that HNP 1-3 are carried into the bloodstream by attaching to high mass plasma proteins in the tumour microenvironment. We discuss the effect of HNP 1-3 on tumour progression.
Adaptogenic and nootropic activities of aqueous extract of Vitis vinifera (grape seed): an experimental study in rat model
Authors: Sreemantula Satyanarayana , Nammi Srinivas , Kolanukonda Rajabhanu , Koppula Sushruta , Boini Krishna M
Published: January 2005

Background

The aerial parts of Vitis vinifera (common grape or European grape) have been widely used in Ayurveda to treat a variety of common and stress related disorders. In the present investigation, the seed extract of V. vinifera was evaluated for antistress activity in normal and stress induced rats. Furthermore, the extract was studied for nootropic activity in rats and in-vitro antioxidant potential to correlate its antistress activity.

Methods

For the evaluation of antistress activity, groups of rats (n = 6) were subjected to forced swim stress one hour after daily treatment of V. vinifera extract. Urinary vanillylmandelic acid (VMA) and ascorbic acid were selected as non-invasive biomarkers to assess the antistress activity. The 24 h urinary excretion of vanillylmandelic acid (VMA) and ascorbic acid were determined by spectrophotometric methods in all groups under normal and stressed conditions. The nootropic activity of the extract as determined from acquisition, retention and retrieval in rats was studied by conditioned avoidance response using Cook's pole climbing apparatus. The in vitro antioxidant activity was determined based on the ability of V. vinifera to scavenge hydroxyl radicals.

Results

Daily administration of V. vinifera at doses of 100, 200 and 300 mg/kg body weight one hour prior to induction of stress inhibited the stress induced urinary biochemical changes in a dose dependent manner. However, no change in the urinary excretion of VMA and ascorbic acid was observed in normal animals at all the doses studied. The cognition, as determined by the acquisition, retention and recovery in rats was observed to be dose dependent. The extract also produced significant inhibition of hydroxyl radicals in comparison to ascorbic acid in a dose dependent manner.

Conclusion

The present study provides scientific support for the antistress (adaptogenic), antioxidant and nootropic activities of V. vinifera seed extract and substantiate the traditional claims for the usage of grape fruits and seeds in stress induced disorders.
Differential effects of IL-10 on prostaglandin H synthase-2 expression and prostaglandin E2 biosynthesis between spleen and bone marrow macrophages
Authors: Shibata Yoshimi , Nishiyama Akihito , Ohata Hiroyoshi , Gabbard Jon , Myrvik Quentin N , Henriksen Ruth Ann
Published: January 2005

Different populations of mononuclear phagocytes (MØ) show considerable diversity of cellular function including prostaglandin E2 (PGE2) biosynthesis. Certain bacterial components enhance PGE2 biosynthesis differentially in selected populations of MØ. Interleukin (IL)-10 is proposed to inhibit modulation of PGE2 biosynthesis by down-regulating prostaglandin G/H synthase-2 (PGHS-2) expression. To assess whether IL-10 regulates PGE2 biosynthesis and PGHS-2 expression, splenic and bone marrow MØ were isolated from IL-10-deficient (IL-10−/−), C57Bl/6 [wild-type (WT) control], and Balb/c (comparison control) mice and were treated with lipopolysaccharide (LPS) and/or interferon-γ (IFN-γ) as a model of bacterial inflammation. LPS-induced PGHS-2 expression was similar for splenic MØ isolated from the three strains of mice. However, PGE2 released by LPS-treated splenic MØ was significantly higher in IL-10−/− and Balb/c than in WT cells. In the presence of LPS and IFN-γ, PGHS-2 expression and PGE2 release by IL-10−/− and Balb/c splenic MØ were enhanced compared with stimulation with LPS alone or IFN-γ alone. However, there was no significant increase in PGE2 release from WT splenic MØ treated with LPS plus IFN-γ despite increased PGHS-2 expression. In sharp contrast, PGHS-2 expression and PGE2 release by bone marrow MØ were greatly enhanced in IL-10−/− cells compared with control cells. Our results indicate that IL-10 regulation of MØ PGE2 biosynthesis and PGHS-2 expression is compartment-dependent and that PGE2 production is not linked directly to PGHS-2 levels. Furthermore, our findings emphasize strain-specific differences between C57Bl/6 and Balb/c mice, and Balb/c appears more similar to the IL-10−/− than to the C57Bl/6 with respect to prostanoid production.
The Vascular Endothelial Growth Factor‐Induced Disruption of Gap Junctions Is Relayed by an Autocrine Communication via ATP Release in Coronary Capillary Endothelium
Authors: THURINGER DOMINIQUE
Published: January 2005

Abstract: Little is known concerning how the coordination of Ca2+ signaling aids in capillary endothelial cell (CEC) functions, such as microvascular permeability and angiogenesis. Previous reports support the major involvement of gap junction (GJ) channels. However, the cell‐to‐cell communication may not be straightforward, especially if we consider the participation of active molecules released by CEC. In this study, short‐term effects of vascular endothelial growth factor (VEGF‐165) were compared with those of bradykinin (BK) on gap junction coupling (GJC) and remodeling of connexin‐43 (Cx43) and then analyzed for intercellular Ca2+ signal in primary cultures of coronary CEC. Dye‐coupling experiments revealed that BK or VEGF completely blocked GJC. These effects correlated with the rapid internalization of Cx43 and its tyrosine phosphorylation in part via the phosphatidylinositol 3‐kinase/Akt pathway. GJC slowly recovered with BK but not with VEGF in the following hour. In control conditions, mechanical stimulation of a single cell within a confluent monolayer triggered an intercellular Ca2+ wave that was partially inhibited by GJC blockers or purinergic inhibitors. No wave propagation was observed after blockage of both GJC and purinergic receptors. Cell treatment with VEGF also reduced propagation of the Ca2+ wave, which was totally prevented by applying a purinergic receptor antagonist but not with a GJC blocker. That excludes purine efflux through Cx hemichannels. We conclude that VEGF‐induced disruption of GJC via Cx43 remodeling is relayed by an autocrine communication via secretion of ATP to preserve intercellular Ca2+ signaling in capillary endothelium.
The Cyclooxygenase Inhibitor Flurbiprofen Reduces Radiation‐Induced Angiogenic Growth Factor Secretion of Squamous Cell Carcinoma Cell Lines
Authors: BRIEGER JÜRGEN , SCHROEDER PETRA , GOSEPATH JAN , MANN WOLF J.
Published: January 2005

Abstract: Surgical intervention and radiotherapy still represent the gold standard in the therapy of head and neck squamous cell carcinoma (SCC), although often with unsatisfactory results. Radiation might induce the expression and secretion of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) by unknown mechanisms. These two highly active proangiogenic and cytoprotective factors might contribute to a limited therapeutic success by promoting revascularization and cytoprotection of the radiated tumor. The aim of the present study was to analyze the potential of the cyclooxygenase inhibitor flurbiprofen to reduce radiation‐induced increase of VEGF and bFGF secretion of tumor cells. We analyzed the expression of VEGF and bFGF at 72 h after radiation with 30 Gy in four SCC cell lines (De‐pt, Hun, Lau, and A549) in cell culture with or without added flurbiprofen. Controls were not exposed to radiation and were analyzed at the same time after culture in the same media. We observed increased VEGF levels in all and increased bFGF levels in three of four lines after radiation. In irradiated cultures with flurbiprofen, VEGF was reduced between 13% and 26% and bFGF was reduced between 84% and 93% compared with radiated cultures without flurbiprofen. We found no reduction of VEGF and bFGF secretion in the unirradiated cultures despite added flurbiprofen. We conclude that flurbiprofen is able to alter the radiation‐induced secretion of these two growth factors and might be useful in decreasing the resistance of SCC to radiation.
Design and Characterization of a New Class of Inhibitors of Ras Activation
Authors: COLOMBO SONIA , PERI FRANCESCO , TISI RENATA , NICOTRA FRANCESCO , MARTEGANI ENZO
Published: January 2005

Abstract: The Ras proteins, which regulate intracellular signaling by a cyclic process involving interconversion between active GTP‐bound and inactive GDP‐bound states, play an essential role in controlling the activity of several crucial signaling pathways regulating normal cellular proliferation. Mutational activation of RAS genes can induce cancer in humans and other mammals. About 30% of human tumors contain an altered oncogenic Ras; therefore, inhibitors of Ras activation are potentially antineoplastic drugs. In this work we describe original molecules acting as Ras inhibitors. Recently a new class of inhibitors of the Ras nucleotide exchange process was described by Taveras et al. These molecules are able to form a noncovalent complex with Ras‐GDP, inhibiting the GDP‐GTP nucleotide exchange. We synthesized molecule SCH‐53870 and we found that it inhibits p21‐hRas nucleotide exchange in vitro, but it has very low solubility in water and undergoes rapid degradation at room temperature when dissolved in water‐DMSO mixtures. This chemical instability could prejudice pharmacological activity in vivo. With the aim to improve solubility and chemical stability, we designed and synthesized other original bioactive molecules that have been characterized in vitro using purified human and yeast Ras proteins and in vivo using suitable Saccharomyces cerevisiae strains. In the long term we hope that the knowledge we derive from these compounds will help in the development of an alternative therapy targeting Ras for a specific inhibition of transformed cell proliferation.
Epidermal Growth Factor Receptor as a Novel Therapeutic Target in Anaplastic Thyroid Carcinomas
Authors: ENSINGER C , SPIZZO G , MOSER P , TSCHOERNER I , PROMMEGGER R , GABRIEL M , MIKUZ G , SCHMID K W
Published: January 2005

Abstract: Anaplastic thyroid carcinoma (ATC) is one of the most aggressive human malignancies, with a median survival of up to 6 months. Such a bad prognosis under the present treatment procedures suggests the need for novel approaches in the management of this disease. Since some epidermal growth factor receptor (EGFR) inhibitors are now in clinical trials and few data are available concerning EGFR expression in anaplastic thyroid carcinomas, we tried to estimate a possible overexpression of this receptor in a larger tumor series. Twenty‐five ATCs, including 3 ATCs with poorly differentiated thyroid carcinoma (PDTC) parts, were immunohistochemically investigated with a mouse monoclonal antibody directed against EGFR (EGFR pharmDX kit). The tumors revealed primarily a distinct membranous staining pattern, and in several tumor cells an additional cytoplasmic reactivity could be observed. The anaplastic carcinomas presented with 5 of 25 (20%) without EGFR reaction, 10 of 25 (40%) with reactivity, and 10 of 25 (40%) with overexpression of the receptor. All ATCs with PDTC parts (100%) showed EGFR overexpression. Cytoplasmic reactivity was observed in 56% of all ATCs. A significant correlation was calculated for EGFR overexpression and cytoplasmic staining (P= 0.036). Concerning receptor overexpression, ATCs were significantly different from ATCs with PDTC parts (P= 0.023). For the first time, we present EGFR overexpression in ATC in a larger tumor series, demonstrating that EGFR overexpression is a common finding in ATC. For at least one‐third of all anaplastic thyroid carcinomas, EGFR seems to be a promising agent for the targeted molecular therapy of these extraordinarily aggressive tumors.
Analysis of the Effects of Different Alcohols on MCF‐7 Human Breast Cancer Cells
Authors: ETIQUE NICOLAS , CHARDARD DOMINIQUE , CHESNEL AMAND , FLAMENT STEPHANE , GRILLIER‐VUISSOZ ISABELLE
Published: January 2005

Abstract: Alcohol consumption is known to be an increased risk factor for breast cancer, but the underlying molecular mechanisms are not well understood. We have recently shown that the exposure of MCF‐7 breast cancer cells to 0.1% ethanol enhanced their proliferation and increased their content in both estrogen receptor‐α (ERα) and aromatase. The aim of the present work was to determine if the effects of ethanol could be mimicked by other short‐chain aliphatic alcohols such as methanol and 1‐butanol. Our results show that these compounds do not stimulate MCF‐7 cell proliferation. An increase in ERα content was observed by Western blot in methanol‐treated cells, but this parameter was not affected in butanol‐treated cells. Neither of these two alcohols induced an increase in aromatase mRNA level. So despite a similarity in molecular structure, these primary alcohols do not exert the same effects. Taken together, these results suggest that the increase in aromatase expression might be a key event required for the enhanced proliferation observed in the presence of ethanol.
Enhancement of Tumor Response by Farnesyltransferase Inhibitor in C3H/HeJ Hepatocarcinoma
Authors: KIM JIYOUNG , SEONG JINSIL , KIM SUNG HEE
Published: January 2005

Abstract: Farnesyltransferase inhibitor (FTI) acts on ras, which can ultimately enhance radiosensitivity. The objective of this study was to explore whether FTI could potentiate the antitumor efficacy of radiation in vivo, particularly in radio‐resistant hepatocarcinomas (HCa‐I) syngeneic to C3H/HeJ mice. The presence of ras mutations was examined by PCR and DNA sequencing. C3H/HeJ mice, bearing HCa‐I, were treated with FTI, LB42907, and 25 Gy radiation. FTI was orally administered, 60 mg/kg, twice daily for 30 days. The expression of regulating molecules was analyzed by Western blotting for p53, p21WAF1/CIP1, and the Bcl‐2 family, such as Bcl‐2, Bax, and Bcl‐XL/s. In HCa‐I, no ras mutations were detected. Downregulation of ras by FTI was most prominent at 4 h after treatment. In a tumor growth delay assay, FTI increased the effect of the tumor's radioresponse, with an enhancement factor of 1.32. Combined irradiation and FTI increased radiation‐induced apoptosis; the peak apoptotic index was 3.6% with irradiation alone and with the drug alone but 7.1% in the combined treatment group. The analysis of apoptosis‐regulating molecules by Western blotting showed upregulation of p53 and p21WAF1/CIP1 in the combined treatment group compared with those in either of the single treatment groups, but the Bcl‐2 family remained unchanged. FTI, in combination with radiation therapy, may have potential benefits in cancer treatment even if there are no ras mutations. FTI could inhibit ras activity but may also affect any protein that requires farnesylation for its activity.
Three‐Dimensional Bioreactor Cultures: A Useful Dynamic Model for the Study of Cellular Interactions
Authors: KONSTANTINOV SPIRO M. , MINDOVA MINA M. , GOSPODINOV PANAYOT T. , GENOVA PENKA I.
Published: January 2005

Abstract: The ex vivo expansion of hematopoietic cells is a developing area with emphasis on bioreactor systems for amelioration of culture conditions. A rational design of bioreactors, especially those allowing microgravity, could permit the production of stem cells and will offer new approaches for studying the mechanisms of proliferation, differentiation, and signal transduction of cultured cells. The efficacy of two commercially available bioreactors (rotating‐vessel miniPERM and static INTEGRA CL 350) to support long‐term bone marrow cell cultures (LTBMCC) and three‐dimensional growth of Hodgkin's lymphoma HD‐MY‐Z cells was investigated. In the miniPERM system, the growth of LTBMCC spheroids (containing 30‐40 cells) was obtained. An essentially higher content of hematopoietic precursor cells (colony‐forming units‐granulocyte macrophage) was registered in the rotating‐vessel system. In this bioreactor, a growth of large HD‐MY‐Z spheroids (containing 100‐200 cells) was achieved. The composed mathematical models of the physicomechanical behavior of spheroids enabled the evaluation of the revolution frequency increase schedule. The differential equations took into account all inertial effects caused by the production module rotation movement as well as those caused by the relative movement of the spheroid in the fluid. The models aimed at the optimization of the rotation frequency increase schedule for different types of cells to reduce shear stress, augment productivity, and tolerate the growth of large spheroids. The models were numerically tested using MATLAB‐SIMULINK software, and the trajectories of prestained HD‐MY‐Z spheroids were filmed. The coincidence of the theoretical and experimental trajectories was sufficient.
Role of the Hedgehog/Patched Signaling Pathway in Oncogenesis: A New Polymorphism in the PTCH Gene in Ovarian Fibroma
Authors: LEVANAT SONJA , MUSANI VESNA , KOMAR ARIJANA , OREŠKOVIĆ S
Published: January 2005

Abstract: We compared the expression of target genes of Hedgehog/Patched signaling in ovarian fibromas and ovarian dermoids. We noted that high levels of SHH appear almost regularly, especially in dermoids, usually accompanied by increased expression of SMO. GLI overexpression does not coincide with that of PTCH. Loss of heterozygosity findings in the PTCH locus and increased expression of several genes in the pathway strongly suggest that the pathway is involved in both ovarian fibroma and dermoids.
Effects of Oxalate on IMCD Cells: A Line of Mouse Inner Medullary Collecting Duct Cells
Authors: MARONI PAUL D. , KOUL SWEATY , MEACHAM RANDALL B. , CHANDHOKE PARAMJIT S. , KOUL HARI K.
Published: January 2005

Abstract: Oxalate, a metabolic end product and a major constituent of the majority of renal stones, has been shown to be toxic to renal epithelial cells of cortical origin. However, it is unknown whether inner medullary collecting duct (IMCD) cells that are physiologically exposed to higher concentrations of oxalate also behave in a similar manner. In the present study, we examined the effects of oxalate on IMCD cells. IMCD cells from the mouse were maintained in DMEM/F12 media supplemented with fetal bovine serum and antibiotics. Exposure of IMCD cells to oxalate produced time‐ and concentration‐dependent changes in the light microscopic appearance of the cells. Long‐term exposure to oxalate resulted in alterations in cell viability, with net cell loss after exposure to concentrations of 2 mM or greater. The production of free radicals was directly related to the exposure time and the concentration of oxalate. Crystal formation occurred in less than 1 h and cells in proximity to crystals would lose membrane integrity. Compared with IMCD cells, LLC‐PK1 cells as well as HK‐2 cells showed significant toxicity starting at lower oxalate concentrations (0.4 mM or greater). These results provide the first direct demonstration of toxic effects of oxalate in IMCD cells, a line of renal epithelial cells of the inner medullary collecting duct, and suggest that the cells lining the collecting duct are relatively resistant to oxalate toxicity.