bluuebunny/crossref_metadata_2025 huggingface dataset:
Molecular and Functional Signature of Heart Hypertrophy During Pregnancy
Authors: Eghbali Mansoureh , Deva Rupal , Alioua Abderrahmane , Minosyan Tamara Y. , Ruan Hongmei , Wang Yibin , Toro Ligia , Stefani Enrico
Published: May 2005

During pregnancy, the heart develops a reversible physiological hypertrophic growth in response to mechanical stress and increased cardiac output; however, underlying molecular mechanisms remain unknown. Here, we investigated pregnancy-related changes in heart structure, function, and gene expression of known markers of pathological hypertrophy and cell stretching in mice hearts. In late pregnancy, hearts show eccentric hypertrophy, as expected for a response to volume overload, with normal left ventricular diastolic function and a moderate reduction in systolic function. Pregnancy-related physiological heart hypertrophy does not induce expression changes of known markers of pathological hypertrophy like: α- and β-myosin heavy chain, atrial natriuretic factor, phospholamban, and sarcoplasmic reticulum Ca
2+
-ATPase. Instead, it induces the remodeling of Kv4.3 channel and increased c-Src tyrosine kinase activity, a stretch-responsive kinase. Cardiac Kv4.3 channel gene expression was downregulated by ≈3- to 5-fold, both at the mRNA and protein levels, and was paralleled by a reduction in transient outward K
+
currents, a longer action potential and by prolongation of the QT interval. Downregulation of cardiac Kv4.3 transcripts was mimicked by estrogen treatment in ovariectomized mice, and was prevented by the estrogen receptor antagonist ICI 182,780. c-Src activity increased by ≈2-fold in late pregnancy and after estrogen treatment. We propose that, in addition to mechanical stress, the rise of estrogen toward the end of pregnancy contributes to pregnancy-related heart hypertrophy by increased c-Src activity and that the rise of estrogen is one factor that down regulates cardiac Kv4.3 gene expression providing a molecular correlate for a longer QT interval in pregnancy.
COX-2–Derived Prostacyclin Modulates Vascular Remodeling
Authors: Rudic R. Daniel , Brinster Derek , Cheng Yan , Fries Susanne , Song Wen-Liang , Austin Sandra , Coffman Thomas M. , FitzGerald Garret A.
Published: May 2005

Suppression of prostacyclin (PGI
2
) biosynthesis may explain the increased incidence of myocardial infarction and stroke which has been observed in placebo controlled trials of cyclooxygenase (COX)-2 inhibitors. Herein, we examine if COX-2–derived PGI
2
might condition the response of the vasculature to sustained physiologic stress in experimental models that retain endothelial integrity. Deletion of the PGI
2
receptor (IP) or suppression of PGI
2
with the selective COX-2 inhibitor, nimesulide, both augment intimal hyperplasia while preserving luminal geometry in mouse models of transplant arteriosclerosis or flow-induced vascular remodeling. Moreover, nimesulide or IP deletion augments the reduction in blood flow caused by common carotid artery ligation in wild-type mice. Generation of both thromboxane (Tx)A
2
and the isoprostane, 8, 12 –
iso
iPF
2α
-VI, are increased in the setting of flow reduction and the latter increases further on administration of nimesulide. Deletion of the TxA
2
receptor (TP) reduces the hyperplastic response to nimesulide and carotid ligation, despite further augmentation of TP ligand production. Suppression of COX-2–derived PGI
2
or deletion of IP profoundly influences the architectural response of the vasculature to hemodynamic stress. Mechanism based vascular remodeling may interact with a predisposition to hypertension and atherosclerosis in contributing to the gradual transformation of cardiovascular risk during extended periods of treatment with selective inhibitors of COX-2.
Proinflammatory Activation of Macrophages by Basic Calcium Phosphate Crystals via Protein Kinase C and MAP Kinase Pathways
Authors: Nadra Imad , Mason Justin C. , Philippidis Pandelis , Florey Oliver , Smythe Cheryl D.W. , McCarthy Geraldine M. , Landis Robert C. , Haskard Dorian O.
Published: May 2005

Basic calcium phosphate (BCP) crystal deposition underlies the development of arterial calcification. Inflammatory macrophages colocalize with BCP deposits in developing atherosclerotic lesions and in vitro can promote calcification through the release of TNF alpha. Here we have investigated whether BCP crystals can elicit a proinflammatory response from monocyte-macrophages. BCP microcrystals were internalized into vacuoles of human monocyte-derived macrophages in vitro. This was associated with secretion of proinflammatory cytokines (TNFα, IL-1β and IL-8) capable of activating cultured endothelial cells and promoting capture of flowing leukocytes under shear flow. Critical roles for PKC, ERK1/2, JNK, but not p38 intracellular signaling pathways were identified in the secretion of TNF alpha, with activation of ERK1/2 but not JNK being dependent on upstream activation of PKC. Using confocal microscopy and adenoviral transfection approaches, we determined a specific role for the PKC-alpha isozyme. The response of macrophages to BCP crystals suggests that pathological calcification is not merely a passive consequence of chronic inflammatory disease but may lead to a positive feed-back loop of calcification and inflammation driving disease progression.
Markers of Endothelial and Hemostatic Activation and Progression of Cerebral White Matter Hyperintensities
Authors: Markus Hugh S. , Hunt Beverley , Palmer Kiran , Enzinger Christian , Schmidt Helena , Schmidt Reinhold
Published: May 2005

Background and Purpose—

The pathogenesis of cerebral small vessel disease (SVD) is poorly understood, but endothelial activation and dysfunction may play a causal role. Cross-sectional studies have found increased circulating markers of endothelial activation, but this study design cannot exclude causality from secondary elevations. Confluent white matter hyperintensities (WMHs) on magnetic resonance imaging (MRI) appear to represent asymptomatic cerebral SVD. In a prospective study, we determined whether circulating markers of endothelial activation predicted progression of WMH.

Methods—

In the community-based Austrian Stroke Prevention Study, MRI was performed at baseline in 296 subjects and repeated at 3 and 6 years. The following were measured on baseline plasma samples: intercellular adhesion molecule (ICAM), thrombomodulin, tissue factor plasma inhibitor, prothrombin fragments 1 and 2, and D-dimers.

Results—

ICAM was associated with age- and gender-adjusted WMH lesion progression at both 3 and 6 years, respectively; (odds ratio [OR], 1.007; 95% confidence interval [CI], 1.002 to 1.012;
P
=0.004; and OR, 1.004; 95% CI, 1.000 to 1.009 per ng/mL;
P
=0.057). After multivariate analysis controlling for other cardiovascular risk factors and C-reactive protein, 3-year OR was 1.010 (95% CI, 1.004 to 1.017;
P
=0.001) and 6-year OR was 1.008 (1.002 to 1.014 per ng/mL;
P
=0.006). Baseline log lesion volume was a strong independent predictor of progression but associations remained after controlling for this (3-year OR, 1.011; 95% CI, 1.002 to 1.020;
P
=0.013; and 6-year OR, 1.009; 95% CI, 1.000 to 1.017;
P
=0.039 per ng/mL). There was no association between WMH progression and other markers.

Conclusions—

ICAM levels are related to progression of WMH on MRI. The prospective study design increases the likelihood that this association is causal and supports a role of endothelial cell activation in disease pathogenesis. In contrast, we found no evidence for coagulation activation being important.
The Safety of Rosuvastatin as Used in Common Clinical Practice
Authors: Alsheikh-Ali Alawi A. , Ambrose Marietta S. , Kuvin Jeffrey T. , Karas Richard H.
Published: May 2005

Background—

Statins are currently the mainstay of dyslipidemia management for the primary and secondary prevention of cardiovascular disease. Controversial concerns about the safety of the newly marketed statin rosuvastatin have been raised on the basis of premarketing studies and a few postmarketing reports.

Methods and Results—

We reviewed rosuvastatin-associated adverse events reported to the US Food and Drug Administration over its first year of marketing. On the basis of prescription data obtained from IMS Health, rates of adverse event reports (AERs) per million prescriptions were calculated. Rates of rosuvastatin-associated AERs over its first year of marketing were compared with those seen with atorvastatin, simvastatin, and pravastatin over the concurrent timeframe and during their respective first years of marketing. Comparison was also made to the first year of marketing of cerivastatin. The primary analysis examined the composite end point of AERs of rhabdomyolysis, proteinuria, nephropathy, or renal failure. With either timeframe comparison, rosuvastatin was significantly more likely to be associated with the composite end point of rhabdomyolysis, proteinuria, nephropathy, or renal failure AERs. Reported cases of rhabdomyolysis, proteinuria, or renal failure tended to occur early after the initiation of therapy and at relatively modest doses of rosuvastatin. The increased rate of rosuvastatin-associated AERs relative to other widely used statins was also observed in secondary analyses when other categories of AERs were examined, including adverse events with serious outcomes, liver toxicity, and muscle toxicity without rhabdomyolysis.

Conclusions—

The present analysis supports concerns about the relative safety of rosuvastatin at the range of doses used in common clinical practice in the general population.
Auf die Schiffe, ihr Pädagogen! Ein einführender Textkommentar zu Nietzsches Aphorismensammlung Die fröhliche Wissenschaft
Authors: Niemeyer Christian
Published: May 2005

Not only does Nietzsche anticipate the doctrine of the Eternal Recurrence and the diagnosis of God's death in his collection of aphorisms "The Gay Science" (1882), but he also suggests what is later exposed more explicitly in Beyond Good and Evil (1886) and in "On the Genealogy of Morals" (1887): the project of an anti-metaphysical human science with a strong psychological focus and the task for 'new philosophers' to discover and reclaim 'another world' of knowledge and life. In this respect, "The Gay Science" has not been paid adequate attention and has been underestimated so far, in particular by German-speaking educationalists.
Rainfall Estimation with a Polarimetric Prototype of WSR-88D
Authors: Ryzhkov Alexander V. , Giangrande Scott E. , Schuur Terry J.
Published: May 2005

As part of the Joint Polarization Experiment (JPOLE), the National Severe Storms Laboratory conducted an operational demonstration of the polarimetric utility of the Norman, Oklahoma (KOUN), Weather Surveillance Radar-1988 Doppler (WSR-88D). The capability of the KOUN radar to estimate rainfall is tested on a large dataset representing different seasons and different types of rain. A dense gauge network—the Agricultural Research Service (ARS) Micronet—is used to validate different polarimetric algorithms for rainfall estimation. One-hour rain totals are estimated from the KOUN radar using conventional and polarimetric algorithms and are compared with hourly accumulations measured by the gauges. Both point and areal rain estimates are examined. A new “synthetic” rainfall algorithm has been developed for rainfall estimation. The use of the synthetic polarimetric algorithm results in significant reduction in the rms errors of hourly rain estimates when compared with the conventional nonpolarimetric relation: 1.7 times for point measurements and 3.7 times for areal rainfall measurements.
Small peptide inhibitors of the CXCR4 chemokine receptor (CD184) antagonize the activation, migration, and antiapoptotic responses of CXCL12 in chronic lymphocytic leukemia B cells
Authors: Burger Meike , Hartmann Tanja , Krome Myriam , Rawluk Justyna , Tamamura Hirokazu , Fujii Nobutaka , Kipps Thomas J. , Burger Jan A.
Published: May 2005

Growth and survival of chronic lymphocytic leukemia (CLL) B cells are favored by interactions between CLL and nontumoral accessory cells. CLL cells express CXCR4 chemokine receptors that direct leukemia cell chemotaxis. Marrow stromal cells or nurselike cells constitutively secrete CXCL12, the ligand for CXCR4, thereby attracting and rescuing CLL B cells from apoptosis in a contact-dependent fashion. Therefore, the CXCR4-CXCL12 axis represents a potential therapeutic target in CLL. We evaluated the most active CXCR4-specific antagonists (T140, TC14012, TN14003) for their capacity to inhibit CXCL12 responses in CLL cells. T140, or its analogs, inhibited actin polymerization, chemotaxis, and migration of CLL cells beneath stromal cells. CXCL12-induced phosphorylation of p44/42 mitogen-activated protein kinase (MAPK) and signal transducer and activator of transcription 3 (STAT3) was abolished by CXCR4 antagonists. TC14012 and TN14003 antagonized the antiapoptotic effect of synthetic CXCL12 and stromal cell-mediated protection of CLL cells from spontaneous apoptosis. Furthermore, we found that stromal cells protected CLL cells from chemotherapy-induced apoptosis. Treatment with CXCR4 antagonists resensitized CLL cells cultured with stromal cells to fludarabine-induced apoptosis. These findings demonstrate that CXCR4 blocking agents effectively antagonize CXCL12-induced migratory and signaling responses and stromal protection of CLL cells from spontaneous or fludarabine-induced apoptosis. As such, small molecular CXCR4 antagonists may have activity in the treatment of patients with this disease. (Blood. 2005;106:1824-1830)
Gene expression and thioguanine nucleotide disposition in acute lymphoblastic leukemia after in vivo mercaptopurine treatment
Authors: Zaza Gianluigi , Cheok Meyling , Yang Wenjian , Panetta John C. , Pui Ching-Hon , Relling Mary V. , Evans William E.
Published: May 2005

To elucidate interpatient variability in thioguanine nucleotide (TGN) concentrations in acute lymphoblastic leukemia (ALL) cells, we determined the TGN concentrations in leukemic blasts from 82 children with newly diagnosed ALL after intravenous administration of mercaptopurine (MP). Patients treated with MP alone achieved higher TGN concentrations than those treated with the combination of methotrexate plus mercaptopurine (MTX + MP). Analysis of the expression of approximately 9600 genes in ALL cells obtained at diagnosis identified 60 gene probes significantly associated with TGN accumulation in patients treated with MP alone and 75 gene probes in patients treated with MTX + MP, with no overlap between the 2 sets of genes. Genes significantly associated with intracellular TGN accumulation after MP alone included those encoding MP metabolic enzymes and transporters (eg, SLC29A1). Inhibition of SLC29A1 by nitrobenzylmercaptopurine ribonucleoside (NBMPR) caused a 33% to 45% reduction of TGN in ALL cells in vitro (P < .006), consistent with the gene expression findings. Genes associated with TGN concentration after combination therapy included those involved in protein and adenosine triphosphate (ATP)-biosynthesis. Together, these in vivo and in vitro data provide new insight into the genomic basis of interpatient differences in intracellular TGN accumulation and reveal significant differences between treatment with MP alone and treatment with MP and MTX. (Blood. 2005;106:1778-1785)
Early proliferation of CCR5+ CD38+++ antigen-specific CD4+ Th1 effector cells during primary HIV-1 infection
Authors: Zaunders John J. , Munier Mee Ling , Kaufmann Daniel E. , Ip Susanna , Grey Pat , Smith Don , Ramacciotti Tim , Quan Dick , Finlayson Robert , Kaldor John , Rosenberg Eric S. , Walker Bruce D. , Cooper David A. , Kelleher Anthony D. ,   on behalf of the PHAEDRA Study Team
Published: May 2005

We investigated whether HIV-1 antigen-specific CD4+ T cells expressed the viral coreceptor CCR5 during primary HIV-1 infection (PHI). In the peripheral blood of subjects with very early PHI (< 22 days after onset of symptoms), there was a 10- to 20-fold increase in the proportion of highly activated (CD38+++) and proliferating (Ki-67+) CD4+ T cells that expressed CCR5+, and were mostly T-cell intracellular antigen-1 (TIA-1)+ perforin+ granzyme B+. Inthe same patient samples, CD4+ T cells producing interferon (IFN)–γ in response to HIV group-specific antigen (Gag) peptides were readily detected (median, 0.58%) by intracellular cytokine assay—these cells were again predominantly CD38+++, Ki-67+, and TIA-++, as well as Bcl-2low. On average, 20% of the Gag-specific CD4+ T cells also expressed interleukin-2 (IL-2) and were CD127 (IL-7R)+. Taken together, these results suggest that Gag-specific T-helper 1 (Th1) effector cells express CCR5 during the primary response and may include precursors of long-term self-renewing memory cells. However, in PHI subjects with later presentation, antigen-specific CD4+ T cells could not be readily detected (median, 0.08%), coinciding with a 5-fold lower level of the CCR5+CD38+++ CD4+ T cells. These results suggest that the antiviral response to HIV-1 infection includes highly activated CCR5+CD4+ cytotoxic effector cells, which are susceptible to both apoptosis and cytopathic infection with HIV-1, and rapidly decline.
FADD and caspase-8 are required for cytokine-induced proliferation of hemopoietic progenitor cells
Authors: Pellegrini Marc , Bath Sue , Marsden Vanessa S. , Huang David C. S. , Metcalf Donald , Harris Alan W. , Strasser Andreas
Published: May 2005

The role of caspase-8 and its adaptor Fas-associated death domain (FADD) in lymphocyte apoptosis is well defined, but their functions in other hemopoietic lineages are not clear. We were unable to generate transgenic mice expressing dominant inhibitors of FADD or caspase-8 in hemopoietic cells, possibly because their expression may have precluded production of vital hemopoietic cells. When using a retroviral gene delivery system, fetal liver stem cells expressing a dominant-negative mutant of FADD (FADD-DN) were unable to generate myeloid or lymphoid cells upon transplantation into lethally irradiated mice. However, fetal liver stem cells expressing very low levels of the caspase-8 inhibitor cytokine response modifier A (CrmA) could reconstitute the hemopoietic system. This level of CrmA expression provided some protection against Fas ligand (FasL)–induced apoptosis and promoted accumulation of myeloid cells in the bone marrow, but it did not inhibit mitogen-induced proliferation of B or T lymphocytes. Using an in vitro colony formation assay, we found that fetal liver stem cells expressing FADD-DN, CrmA, or a dominant-negative mutant of caspase-8 could not proliferate in response to cytokine stimulation. These data demonstrate that the enzymatic activity of caspase-8 and its adaptor FADD are required for cytokine-induced proliferation of hemopoietic progenitor cells.
The heparin-binding site of antithrombin is crucial for antiangiogenic activity
Authors: Zhang Weiqing , Swanson Richard , Izaguirre Gonzalo , Xiong Yan , Lau Lester F. , Olson Steven T.
Published: May 2005

The heparin-binding site of antithrombin is shown here to play a crucial role in mediating the antiangiogenic activity of conformationally altered cleaved and latent forms of the serpin. Blocking the heparin-binding site of cleaved or latent antithrombin by complexation with a high-affinity heparin pentasaccharide abolished the serpin's ability to inhibit proliferation, migration, capillary-like tube formation, basic fibroblast growth factor (bFGF) signaling, and perlecan gene expression in bFGF-stimulated human umbilical vein endothelial cells. Mutation of key heparin binding residues, when combined with modifications of Asn-linked carbohydrate chains near the heparin-binding site, also could abrogate the anti-proliferative activity of the cleaved serpin. Surprisingly, mutation of Lys114, which blocks anticoagulant activation of antithrombin by heparin, caused the native protein to acquire antiproliferative activity without the need for conformational change. Together, these results indicate that the heparin-binding site of antithrombin is of crucial importance for mediating the serpin's antiangiogenic activity and that heparin activation of native antithrombin constitutes an antiangiogenic switch that is responsible for turning off the antiangiogenic activity of the native serpin.
Unresolved questions, changing definitions, and novel paradigms for defining endothelial progenitor cells
Authors: Ingram David A. , Caplice Noel M. , Yoder Mervin C.
Published: May 2005

The field of vascular biology has been stimulated by the concept that circulating endothelial progenitor cells (EPCs) may play a role in neoangiogenesis (postnatal vasculogenesis). One problem for the field has been the difficulty in accurately defining an EPC. Likewise, circulating endothelial cells (CECs) are not well defined. The lack of a detailed understanding of the proliferative potential of EPCs and CECs has contributed to the controversy in identifying these cells and understanding their biology in vitro or in vivo. A novel paradigm using proliferative potential as one defining aspect of EPC biology suggests that a hierarchy of EPCs exists in human blood and blood vessels. The potential implications of this view in relation to current EPC definitions are discussed.
Effect of increased convective clearance by on-line hemodiafiltration on all cause and cardiovascular mortality in chronic hemodialysis patients – the Dutch CONvective TRAnsport STudy (CONTRAST): rationale and design of a randomised controlled trial [ISRCTN38365125]
Authors: Penne E Lars , Blankestijn Peter J , Bots Michiel L , van den Dorpel Marinus A , Grooteman Muriel P , Nubé Menso J , van der Tweel Ingeborg , ter Wee Piet M ,   the CONTRAST study group
Published: May 2005

Background

The high incidence of cardiovascular disease in patients with end stage renal disease (ESRD) is related to the accumulation of uremic toxins in the middle and large-middle molecular weight range. As online hemodiafiltration (HDF) removes these molecules more effectively than standard hemodialysis (HD), it has been suggested that online HDF improves survival and cardiovascular outcome. Thus far, no conclusive data of HDF on target organ damage and cardiovascular morbidity and mortality are available. Therefore, the CONvective TRAnsport STudy (CONTRAST) has been initiated.

Methods

CONTRAST is a Dutch multi-center randomised controlled trial. In this trial, approximately 800 chronic hemodialysis patients will be randomised between online HDF and low-flux HD, and followed for three years. The primary endpoint is all cause mortality. The main secondary outcome variables are fatal and non-fatal cardiovascular events.

Conclusion

The study is designed to provide conclusive evidence whether online HDF leads to a lower mortality and less cardiovascular events as compared to standard HD.
Detection of nuclei in 4D Nomarski DIC microscope images of early Caenorhabditis elegans embryos using local image entropy and object tracking
Authors: Hamahashi Shugo , Onami Shuichi , Kitano Hiroaki
Published: May 2005

Background

The ability to detect nuclei in embryos is essential for studying the development of multicellular organisms. A system of automated nuclear detection has already been tested on a set of four-dimensional (4D) Nomarski differential interference contrast (DIC) microscope images of Caenorhabditis elegans embryos. However, the system needed laborious hand-tuning of its parameters every time a new image set was used. It could not detect nuclei in the process of cell division, and could detect nuclei only from the two- to eight-cell stages.

Results

We developed a system that automates the detection of nuclei in a set of 4D DIC microscope images of C. elegans embryos. Local image entropy is used to produce regions of the images that have the image texture of the nucleus. From these regions, those that actually detect nuclei are manually selected at the first and last time points of the image set, and an object-tracking algorithm then selects regions that detect nuclei in between the first and last time points. The use of local image entropy makes the system applicable to multiple image sets without the need to change its parameter values. The use of an object-tracking algorithm enables the system to detect nuclei in the process of cell division. The system detected nuclei with high sensitivity and specificity from the one- to 24-cell stages.

Conclusion

A combination of local image entropy and an object-tracking algorithm enabled highly objective and productive detection of nuclei in a set of 4D DIC microscope images of C. elegans embryos. The system will facilitate genomic and computational analyses of C. elegans embryos.
Conserved genomic organisation of Group B Sox genes in insects.
Authors: McKimmie Carol , Woerfel Gertrud , Russell Steven
Published: May 2005

Background

Soxdomain containing genes are important metazoan transcriptional regulators implicated in a wide rage of developmental processes. The vertebrate B subgroup contains theSox1,Sox2 and Sox3genes that have early functions in neural development. Previous studies show thatDrosophilaGroup B genes have been functionally conserved since they play essential roles in early neural specification and mutations in theDrosophila DichaeteandSoxNgenes can be rescued with mammalianSoxgenes. Despite their importance, the extent and organisation of the Group B family inDrosophilahas not been fully characterised, an important step in usingDrosophilato examine conserved aspects of Group BSoxgene function.

Results

We have used the directed cDNA sequencing along with the output from the publicly-available genome sequencing projects to examine the structure of Group BSoxdomain genes inDrosophila melanogaster,Drosophila pseudoobscura, Anopheles gambiaeandApis mellifora. All of the insect genomes contain four genes encoding Group B proteins, two of which are intronless, as is the case with vertebrate group B genes. As has been previously reported and unusually for Group B genes, two of the insect group B genes,Sox21aandSox21b, contain introns within their DNA-binding domains. We find that the highly unusual multi-exon structure of theSox21bgene is common to the insects. In addition, we find that three of the group BSoxgenes are organised in a linked cluster in the insect genomes. Byin situhybridisation we show that the pattern of expression of each of the four group B genes during embryogenesis is conserved betweenD. melanogasterandD. pseudoobscura.

Conclusion

The DNA-binding domain sequences and genomic organisation of the group B genes have been conserved over 300 My of evolution since the last common ancestor of the Hymenoptera and the Diptera. Our analysis suggests insects have two Group B1 genes,SoxNandDichaete, and two Group B2 genes. The genomic organisation ofDichaeteand another two Group B genes in a cluster, suggests they may be under concerted regulatory control. Our analysis suggests a simple model for the evolution of group B Sox genes in insects that differs from the proposed evolution of vertebrate Group B genes.
Control of gene expression during T cell activation: alternate regulation of mRNA transcription and mRNA stability
Authors: Cheadle Chris , Fan Jinshui , Cho-Chung Yoon S , Werner Thomas , Ray Jill , Do Lana , Gorospe Myriam , Becker Kevin G
Published: May 2005

Background

Microarray technology has become highly valuable for identifying complex global changes in gene expression patterns. The effective correlation of observed changes in gene expression with shared transcription regulatory elements remains difficult to demonstrate convincingly. One reason for this difficulty may result from the intricate convergence of both transcriptional and mRNA turnover events which, together, directly influence steady-state mRNA levels.

Results

In order to investigate the relative contribution of gene transcription and changes in mRNA stability regulation to standard analyses of gene expression, we used two distinct microarray methods which individually measure nuclear gene transcription and changes in polyA mRNA gene expression. Gene expression profiles were obtained from both polyA mRNA (whole-cell) and nuclear run-on (newly transcribed) RNA across a time course of one hour following the activation of human Jurkat T cells with PMA plus ionomycin. Comparative analysis revealed that regulation of mRNA stability may account for as much as 50% of all measurements of changes in polyA mRNA in this system, as inferred by the absence of any corresponding regulation of nuclear gene transcription activity for these groups of genes. Genes which displayed dramatic elevations in both mRNA and nuclear run-on RNA were shown to be inhibited by Actinomycin D (ActD) pre-treatment of cells while large numbers of genes regulated only through altered mRNA turnover (both up and down) were ActD-resistant. Consistent patterns across the time course were observed for both transcribed and stability-regulated genes.

Conclusion

We propose that regulation of mRNA stability contributes significantly to the observed changes in gene expression in response to external stimuli, as measured by high throughput systems.
Identification, characterization and metagenome analysis of oocyte-specific genes organized in clusters in the mouse genome
Authors: Paillisson Amélie , Dadé Sébastien , Callebaut Isabelle , Bontoux Martine , Dalbiès-Tran Rozenn , Vaiman Daniel , Monget Philippe
Published: May 2005

Background

Genes specifically expressed in the oocyte play key roles in oogenesis, ovarian folliculogenesis, fertilization and/or early embryonic development. In an attempt to identify novel oocyte-specific genes in the mouse, we have used an in silico subtraction methodology, and we have focused our attention on genes that are organized in genomic clusters.

Results

In the present work, five clusters have been studied: a cluster of thirteen genes characterized by an F-box domain localized on chromosome 9, a cluster of six genes related to T-cell leukaemia/lymphoma protein 1 (Tcl1) on chromosome 12, a cluster composed of a SPErm-associated glutamate (E)-Rich (Speer) protein expressed in the oocyte in the vicinity of four unknown genes specifically expressed in the testis on chromosome 14, a cluster composed of the oocyte secreted protein-1 (Oosp-1) gene and two Oosp-related genes on chromosome 19, all three being characterized by a partial N-terminal zona pellucida-like domain, and another small cluster of two genes on chromosome 19 as well, composed of a TWIK-Related spinal cord K+ channel encoding-gene, and an unknown gene predicted in silico to be testis-specific. The specificity of expression was confirmed by RT-PCR and in situ hybridization for eight and five of them, respectively. Finally, we showed by comparing all of the isolated and clustered oocyte-specific genes identified so far in the mouse genome, that the oocyte-specific clusters are significantly closer to telomeres than isolated oocyte-specific genes are.

Conclusion

We have studied five clusters of genes specifically expressed in female, some of them being also expressed in male germ-cells. Moreover, contrarily to non-clustered oocyte-specific genes, those that are organized in clusters tend to map near chromosome ends, suggesting that this specific near-telomere position of oocyte-clusters in rodents could constitute an evolutionary advantage. Understanding the biological benefits of such an organization as well as the mechanisms leading to a specific oocyte expression in these clusters now requires further investigation.
Detection of a highly prevalent and potentially virulent strain of Pseudomonas aeruginosa from nosocomial infections in a medical center
Authors: Matar Ghassan M , Chaar Mira H , Araj George F , Srour Zaher , Jamaleddine Ghassan , Hadi Usamah
Published: May 2005

Background

We correlated genotypes, virulence factors and antimicrobial susceptibility patterns of nosocomially identified Pseudomonas aeruginosa isolates from clinical specimens to those of environmental isolates encountered in the same units of a medical center. Antibiotic susceptibility testing, RAPD analysis and detection of enzymatic activities of extracellular virulence factors, were done on these isolates.

Results

Data showed that most of the clinical and environmental isolates were susceptible to tested antimicrobial agents. RAPD analysis determined the presence of 31 genotypes, with genotype 1 detected in 42% of the clinical isolates and 43% of the environmental isolates. Enzymatic activity testing showed that genotype 1 produced all virulence factors tested for.

Conclusion

In conclusion, our data demonstrated the predominant prevalence of a potentially virulent P. aeruginosa genotype, circulating in a number of units of the medical center and emphasize the need to reinforce infection control measures.
Light-induced morphological alteration in anthocyanin-accumulating vacuoles of maize cells
Authors: Irani Niloufer G , Grotewold Erich
Published: May 2005

Background

Plant pigmentation is affected by a variety of factors. Light, an important plant developmental signal, influences the accumulation of anthocyanins primarily through the activation of the transcription factors that regulate the flavonoid biosynthetic pathway. In this study, we utilized maize Black Mexican Sweet (BMS) cells expressing the R and C1 regulators of anthocyanin biosynthesis from a light-insensitive promoter as a means to investigate the existence of additional levels of control of pigmentation by light.

Results

BMS cells expressing the R and C1 regulators from theCaMV 35Sconstitutive promoter accumulate anthocyanins when grown in complete darkness, suggesting that the transcription factors R and C1 are sufficient for the transcription of the genes corresponding to the structural enzymes of the pathway, with no requirement for additional light-induced regulators. Interestingly, light induces a "darkening" in the color of the purple anthocyanin pigmentation of transgenic BMS cells expressing R and C1. This change in the pigment hue is not associated with a variation in the levels or types of anthocyanins present, or with an alteration of the transcript levels of several flavonoid biosynthetic genes. However, cytological observations show that light drives unexpected changes in the morphology and distribution of the anthocyanins-containing vacuolar compartments.

Conclusion

By uncoupling the effect of light on anthocyanin accumulation, we have found light to induce the fusion of anthocyanin-containing vacuoles, the coalescence of anthocyanic vacuolar inclusion (AVI)-like structures contained, and the spread of anthocyanins from the inclusions into the vacuolar sap. Similar light-induced alterations in vacuolar morphology are also evident in the epidermal cells of maize floral whorls accumulating anthocyanins. Our findings suggest a novel mechanism for the action of light on the vacuolar storage of anthocyanin.
Prognostic value of interleukin-1 receptor antagonist gene polymorphism and cytomegalovirus seroprevalence in patients with coronary artery disease
Authors: Rothenbacher Dietrich , Brenner Hermann , Mertens Thomas , Hoffmann Michael M , Hoffmeister Albrecht , Koenig Wolfgang
Published: May 2005

Background

Chronic inflammatory stimuli such as cytomegalovirus (CMV) infection and various genetic polymorphisms determining the inflammatory response are assumed to be important risk factors in atherosclerosis. We investigated whether patients with stable coronary artery disease (CAD) and homozygous for allele 2 of the interleukin 1 receptor antagonist (IL-1RA) gene and seropositive for CMV represent a group particular susceptible for recurrent cardiovascular events.

Methods

In a series of 300 consecutive patients with angiographically defined CAD a prospective follow-up was conducted (mean age 57.9 years, median follow-up time 38.2 months).

Results

No statistically significant relationship was found between CMV serostatus and IL-1RN*2 (alone or in combination) and risk for future cardiovascular events (CVE). The hazard ratio (HR) for a CVE given positive CMV-serology and IL-1RN*2 was 1.07 (95% confidence interval (CI) 0.32–3.72) in the fully adjusted model compared to seronegative CMV patients not carrying the IL-1RN*2 allele. In this prospective cohort study involving 300 patients with angiographically defined CAD at baseline, homozygousity for allele 2 of the IL-1 RA and seropositivity to CMV alone and in combination were not associated with an increased risk for cardiovascular events during follow-up; in addition, combination of the CMV-seropositivity and IL-1RN*2 allele were not associated with a proinflammatory response

Conclusion

Our study suggests that seropositivity to CMV and IL-1RA*2 genotype alone or in combination might not be a strong risk factor for recurrent cardiovascular events in patients with manifest CAD, and is not associated with levels of established inflammatory markers.
A sensitive flow cytometric methodology for studying the binding of L. chagasito canine peritoneal macrophages
Authors: Gonçalves Ricardo , Vieira Etel R , Melo Maria N , Gollob Kenneth J , Mosser David M , Tafuri Wagner L
Published: May 2005

Background

The Leishmania promastigote-macrophage interaction occurs through the association of multiple receptors on the biological membrane surfaces. The success of the parasite infection is dramatically dependent on this early interaction in the vertebrate host, which permits or not the development of the disease. In this study we propose a novel methodology using flow cytometry to study this interaction, and compare it with a previously described "in vitro" binding assay.

Methods

To study parasite-macrophage interaction, peritoneal macrophages were obtained from 4 dogs and adjusted to 3 × 106 cells/mL. Leishmania (Leishmania) chagasi parasites (stationary-phase) were adjusted to 5 × 107 cells/mL. The interaction between CFSE-stained Leishmania chagasi and canine peritoneal macrophages was performed in polypropylene tubes to avoid macrophage adhesion. We carried out assays in the presence or absence of normal serum or in the presence of a final concentration of 5% of C5 deficient (serum from AKR/J mice) mouse serum. Then, the number of infected macrophages was counted in an optical microscope, as well as by flow citometry. Macrophages obtained were stained with anti-CR3 (CD11b/CD18) antibodies and analyzed by flow citometry.

Results

Our results have shown that the interaction between Leishmania and macrophages can be measured by flow cytometry using the fluorescent dye CFSE to identify the Leishmania, and measuring simultaneously the expression of an important integrin involved in this interaction: the CD11b/CD18 (CR3 or Mac-1) β2 integrin.

Conclusion

Flow cytometry offers rapid, reliable and sensitive measurements of single cell interactions with Leishmania in unstained or phenotypically defined cell populations following staining with one or more fluorochromes.
Pregnancy-induced hypertension and infant growth at 28 and 42 days postpartum
Authors: Baulon Emmanuelle , Fraser William D , Piedboeuf Bruno , Buekens Pierre , Xiong Xu
Published: May 2005

Background

No previous studies have examined the effect of pregnancy-induced hypertension (PIH) on early infant growth. The objective was to study infant growth patterns of babies born to mothers with PIH at 28 and 42 days postpartum.

Methods: Design

We conducted a population-based retrospective cohort study of 16,936 pregnancies delivered between January 1, 1989 through December 31, 1990 in Suzhou, China. PIH was classified as gestational hypertension, preeclampsia and severe preeclampsia. Infant Growth Percentage (IGP) was calculated as the weight gain from birth to infant weight at 28 or 42 days postpartum divided by the birth weight. Univariate analysis and multivariate linear regression were performed to compare the infant weight as well as IGP at 28 and 42 days postpartum between various types of PIH and the normotensive group.

Results

Infant weights at 28 and 42 days postpartum were significantly lower in severe preeclampsia (e.g., 4679.9 g at 42 days) and preeclampsia (e.g., 4763.8 g at 42 days) groups than in the normotensive group (e.g., 4869.1 g at 42 days, p < 0.01). However, there were no differences in IGP between groups. After stratifying by intrauterine growth restriction (IUGR) status, if babies were not intrauterine growth restricted, none of the PIH types showed a significantly lower weight at 28 and 42 days postpartum and their IGPs were similar to those of the reference group. When babies were growth restricted, all PIH groups showed significantly lower weights but higher IGP at 28 and 42 days postpartum as compared to the normotensive group.

Conclusion

Infants born to mothers with PIH but without IUGR have normal early infant growth. IUGR secondary to PIH is associated with significant catch-up growth at 28 and 42 days postpartum.
SSRI'S and other antidepressant use during pregnancy and potential neonatal adverse effects: Impact of a public health advisory and subsequent reports in the news media
Authors: Einarson A , Schachtschneider AK , Halil R , Bollano E , Koren G
Published: May 2005

Background

On Aug 9th 2004 Health Canada released an advisory, which followed a similar one from the FDA regarding the use of SSRI's and other antidepressants during pregnancy and potential adverse effects on newborns. In neither advisory was it stated that women should discontinue their antidepressant. In the seven days following the release of this advisory, The Motherisk Program received 49 calls from anxious women in response to the media reporting of this information.

Objective

To examine the impact of the advisory and subsequent reporting in the media, on the decision-making of women, currently taking an antidepressant, who called The Motherisk Program after becoming aware of this information.

Methods

We attempted to follow up all the women who had called us who were alarmed by this advisory and asked them to complete a specially designed questionnaire.

Results

We were able to complete 43/49 (88%) follow-ups of the women who contacted us. All of the callers reported that the messages in the media caused a great deal of anxiety. Seven misunderstood the advisory, ie their children were more than 1 year old, five had discontinued their antidepressant (3 abruptly (2 later restarted after speaking with Motherisk counsellors)and 2 with some form of tapering off) and(6) were considering discontinuation, but decided to continue following reassurance from Motherisk

Conclusion

Medical information regarding fetal and infant safety, disseminated in the public domain, should be transferred in a way that does not influence a pregnant woman to make decisions that may not be in the best interest of hers or her child's health.
Maspin overexpression modulates tumor cell apoptosis through the regulation of Bcl-2 family proteins
Authors: Zhang Weiguo , Shi Heidi Y , Zhang Ming
Published: May 2005

Background

Maspin is a member of serpin family with tumor suppressing activity. Recent studies of maspin in animal models strongly support maspin's role as an inhibitor against the growth of primary tumor sand the process of metastasis. However, the molecular mechanism underlying this inhibition has not been fully elucidated. In this report, we analyze the effect of maspin on tumor cell apoptosis under several stress conditions.

Methods

Stable clones overexpressing maspin are established in the mouse mammary tumor TM40D cells. They are treated with staurosporine, TNF-alpha, and serum starvation. The rates of cell apoptosis are analyzed by TUNEL assay. Inhibitors against caspase 8 and 9 are used in the apoptosis assay. Western blot analysis and ribonuclease protection assay (RPA) are performed to examine the expression of Bcl2 family genes.

Results

We report that maspin expressing tumor cells have increased rate of apoptosis when they are treated with staurosporine and serum starvation. The effect is not through extracellular maspin. Maspin-mediated apoptosis is partially blocked by caspase 8 and 9 inhibitors, and is accompanied by changes in the Bcl-2 family proteins. Maspin-expressing tumor cells have a reduced level of anti-apoptotic protein Bcl-2, and an increased level of pro-apoptotic protein Bax. The regulation is not controlled at the transcriptional level but is through selective control of Bcl-2 and Bax protein stability.

Conclusion

Maspin overexpression modulates tumor cell apoptosis through the regulation of Bcl2 family proteins. Such change results in an increased release of cytochrome c from mitochondria, thus the increased apoptosis in maspin-expressing cells. This evidence strongly suggests that the induction of apoptosis in maspin-overexpressing cells represents a major mechanism by which maspin inhibits breast tumor progression.
Vitrectomy with complete posterior hyaloid removal for ischemic central retinal vein occlusion: Series of cases
Authors: Leizaola-Fernández Carlos , Suárez-Tatá Luis , Quiroz-Mercado Hugo , Colina-Luquez Juner , Fromow-Guerra J , Jiménez-Sierra Juan M , Guerrero-Naranjo Jose L , Morales-Cantón Virgilio
Published: May 2005

Background

Central retinal vein occlusion (CRVO) is a common retinal vascular disorder with potentially complications: (1) persistent macular edema and (2) neovascular glaucoma. No safe treatment exists that promotes the return of lost vision. Eyes with CRVO may be predisposed to vitreous degeneration. It has been suggested that if the vitreous remains attached to the macula owing to a firm vitreomacular adhesion, the resultant vitreous traction can cause inflammation with retinal capillary dilation, leakage and subsequent edema6. The roll of vitrectomy in ischemic CRVO surgical procedures has not been evaluated.

Case presentation

This is a non comparative, prospective, longitudinal, experimental and descriptive series of cases. Ten eyes with ischemic CRVO. Vitrectomy with complete posterior hyaloid removal was performed. VA, rubeosis, intraocular pressure (IOP), and macular edema were evaluated clinically. Multifocal ERG (m-ERG), fluorescein angiography (FAG) and optic coherence tomography (OCT) were performed. Follow-up was at least 6 months. Moderate improvement of visual acuity was observed in 60% eyes and stabilized in 40%. IOP changed from 15.7 ± 3.05 mmHg to 14.9 ± 2.69 mmHg post-operative and macular edema from 976 ± 196 μm to 640 ± 191 μm to six month. The P1 wave amplitude changed from 25.46 ± 12.4 mV to 20.54 ± 11.2 mV.

Conclusion

A solo PPV with posterior hyaloid removal may help to improve anatomic and functional retina conditions in some cases. These results should be considered when analyzing other surgical maneuvers.
Organisation and financing of the health care systems of Bulgaria and Greece – what are the parallels?
Authors: Exadaktylos Nikolaos M
Published: May 2005

Background

The Bulgarian and Greek Medical Care systems have been reformated the last fifteen years. The aim of this study was an examination and comparison of the Bulgarian and Greek Medical Care Systems.

Methods

This study was prepared by using all the published data related to both Bulgarian and Greek Medical Care systems. Besides, personal communications with related offices such as administration offices of hospitals and Ministries of Health were made.

Results

In both countries, besides the compulsory insurance there is also additional voluntary insurance which is provided by private companies. The most important difference is the family doctor (specialist in general medicine) existing in Bulgaria. Every insured person needs a 'referral form' completed by the family doctor before visiting a hospital for medical attention (except emergencies). In contrast, in Greece an insured person can directly visit any hospital without needing any forms and independent of the severity of their health problem. An important disadvantage of the Greek health system is the low number of hospitals (139), in relation to population. In contrast, there are 211 hospitals in Bulgaria, although its population is lower than in Greece.

Conclusion

In both Greek and Bulgarian health systems changes must be done to solve the problems related to informal payments, limited financing, large debts, lack of appropriate investment policy, lack of an objective method for the costing of medical activities and inefficient management.