bluuebunny/crossref_metadata_2025 huggingface dataset:
Peroxisome Proliferator-Activated Receptor γ Ligands Inhibit Rho/Rho Kinase Pathway by Inducing Protein Tyrosine Phosphatase SHP-2
Authors: Wakino Shu , Hayashi Koichi , Kanda Takeshi , Tatematsu Satoru , Homma Koichiro , Yoshioka Kyoko , Takamatsu Ichiro , Saruta Takao
Published: August 2004

Although peroxisome proliferator-activated receptor γ (PPARγ) ligands have an antihypertensive effect in vivo, the precise mechanism has not been fully elucidated. We examined their effects on Rho/Rho kinase pathway, a key regulator of vascular tone. In cultured rat aortic smooth muscle cells (RASMC), Rho kinase stimulated by angiotensin II was suppressed by the pretreatment with pioglitazone and troglitazone, and these effects were explained by the inhibition of the Rho translocation to the cell membrane. We evaluated the role of Vav, a GTP/GDP exchange factor upregulating Rho kinase activity, and Src homology region 2–containing protein tyrosine phosphatase-2 (SHP-2), a protein tyrosine phosphatase that dephosphorylated Vav and subsequently inactivated Rho kinase. Both pioglitazone and troglitazone upregulated SHP-2, particularly in the cytosolic fraction, and the SHP-2-bound Vav, and reduced the phosphorylation of Vav. Furthermore, 4-week treatment with pioglitazone lowered systolic blood pressure in spontaneously hypertensive rats (SHR) and suppressed the Rho/Rho kinase activity in aortic tissues isolated from SHR. Consistently, the expression of SHP-2 was upregulated in vascular tissues from pioglitazone-treated SHR. The phosphorylated Vav was increased in SHR, compared with that in normotensive Wistar–Kyoto rats (WKY), which was mitigated by pioglitazone. Finally, both basal and angiotensin II–stimulated levels of Rho kinase activity were greater in RASMC from SHR than those from WKY, and the enhanced Rho kinase activity was blocked by pioglitazone or troglitazone in both strains. Collectively, PPARγ ligands inhibit the Rho/Rho kinase pathway through upregulation of cytosolic SHP-2 expression and inactivation of Vav, and may contribute to the hemodynamic, in addition to metabolic, action in hypertensive metabolic syndrome. The full text of this article is available online at http://circres.ahajournals.org.
Serum S100B Predicts a Malignant Course of Infarction in Patients With Acute Middle Cerebral Artery Occlusion
Authors: Foerch Christian , Otto Bettina , Singer Oliver C. , Neumann-Haefelin Tobias , Yan Bernard , Berkefeld Joachim , Steinmetz Helmuth , Sitzer Matthias
Published: August 2004

Background and Purpose—

Early predictors of infarct volume may improve therapeutic decisions in patients with acute cerebral ischemia. We investigated whether measurements of serum astroglial protein S100B can predict a malignant course of infarction in acute middle cerebral artery (MCA) occlusion.

Methods—

We included 51 patients (24 women, mean age 69.1±12.4 years) admitted within 6 hours after stroke symptom onset caused by proximal MCA occlusion, as shown by magnetic resonance angiography (n=39), intra-arterial angiography (n=4), or transcranial duplex sonography (n=8). Blood samples were drawn at hospital admission and 8, 12, 16, 20, and 24 hours after symptom onset. Serum S100B concentrations were determined using a fully automated immunoluminometric assay. A malignant course of infarction was defined as the occurrence of clinical signs of cerebral herniation within the first 7 days of treatment or the clinical decision to perform decompressive hemicraniectomy caused by critical space-occupying swelling as detected by repeated neuroimaging.

Results—

Sixteen patients developed malignant infarction (31%). Beginning with the 12-hour value, mean S100B serum concentrations were significantly higher in patients with a malignant course compared with those without (12 hours 1.23±1.24 versus 0.29±0.45 μg/L; 16 hours 1.80±1.65 versus 0.38±0.53 μg/L; 20 hours 1.90±1.53 versus 0.44±0.48 μg/L; and 24 hours 2.41±1.59 versus 0.57±0.66 μg/L; all
P
<0.001). A 12-hour S100B value >0.35 μg/L predicted malignant infarction with 0.75 sensitivity and 0.80 specificity. A 24-hour value >1.03 μg/L provided 0.94 sensitivity and 0.83 specificity.

Conclusions—

The serum marker S100B can predict a malignant course of infarction in proximal MCA occlusion. This finding may improve the identification and monitoring of patients at particularly high risk for herniation.
Association of Polymorphisms and Haplotypes in the Elastin Gene in Dutch Patients With Sporadic Aneurysmal Subarachnoid Hemorrhage
Authors: Ruigrok Y.M. , Seitz U. , Wolterink S. , Rinkel G.J.E. , Wijmenga C. , Urbán Z.
Published: August 2004

Background and Purpose—

A locus containing the elastin gene has been linked to familial intracranial aneurysms in 2 distinct populations. We investigated the association of single-nucleotide polymorphisms (SNPs) and haplotypes of SNPs in the elastin gene with the occurrence of subarachnoid hemorrhage (SAH) from sporadic aneurysms in the Netherlands.

Methods—

We genotyped 167 SAH patients and 167 matching controls for 18 exonic and intronic SNPs in the elastin gene. A Bonferroni correction was applied for multiple comparisons with all novel associations, with a correction factor derived from the number of SNPs tested (
P
value after Bonferroni correction [
P
corr
]).

Results—

SAH was statistically significant associated with an SNP in exon 22 of the elastin gene (minor allele frequency was 0.000 in patients and 0.028 in controls; odds ratio [OR], 0.0; 95% CI, 0.0 to 0.7;
P
=0.004;
P
corr
=0.05) and possibly with an SNP in intron 5 (minor allele frequency was 0.062 in patients and 0.128 in controls; OR, 0.5; 95% CI, 0.2 to 0.8;
P
=0.007;
P
corr
=0.08). Haplotypes of intron 5/exon 22 (
P
corr
=0.002), intron 4/exon 22 (
P
corr
=0.02), and intron 4/intron 5/exon 22 (
P
=9.0×10
−9
) were also associated with aneurysmal SAH.

Conclusions—

Variants and haplotypes within the elastin gene are associated with the risk of sporadic SAH in Dutch patients. Gradual increase of statistical power with the inclusion of 2 or 3 SNPs in the studied haplotypes supports the validity of our conclusion that the elastin gene is a susceptibility locus for SAH.
Fasting Plasma Glucose and Risk of Incident Ischemic Stroke or Transient Ischemic Attacks
Authors: Tanne David , Koren-Morag Nira , Goldbourt Uri
Published: August 2004

Background and Purpose—

Diabetes and impaired fasting glucose are diagnosed based on an elevated plasma glucose level after an overnight fast. The diagnostic cutpoint of diabetes arises from the threshold for development of microvascular complications. Our aim was to examine the associations between clinical relevant categories of fasting glucose levels and the risk of incident ischemic stroke.

Methods—

Patients with documented coronary heart disease who were screened for inclusion in a secondary prevention clinical trial (n=13 999) were followed-up. At baseline, medical histories were obtained and plasma glucose and lipids assessed at a central study laboratory. During a 6- to 8-year follow-up period 1037 cases were identified with ischemic cerebrovascular disease, of which, after reviewing hospital records with diagnoses of cerebrovascular disease, 576 cases were verified to have had ischemic stroke or transient ischemic attacks.

Results—

Increasing fasting glucose level categories were positively associated with increasing age, male gender, body mass index, hypertension, total cholesterol, and triglycerides, and were inversely associated with high-density lipoprotein cholesterol and percent high-density lipoprotein of total cholesterol. In comparison with patients with fasting glucose levels of 90 to 99 mg/dL (n=3706) who constitute the largest category, the odds ratios of ischemic cerebrovascular disease, adjusting for potential confounders, were 1.47 (95% CI, 1.07 to 2.02) for fasting glucose <80, 1.22 (0.98 to 1.52) for 80 to 89, 1.27 (1.02 to 1.60) for 100 to 109, 1.60 (1.26 to 2.03) for 110 to 125, 1.82 (1.33 to 2.49) for 126 to 140, and 2.82 (2.32 to 3.43) for >140 mg/dL. Similar J-shaped associations were observed in analysis excluding patients with known diagnosis of diabetes mellitus.

Conclusions—

The association between fasting plasma glucose and incident ischemic cerebrovascular events in patients with pre-existing atherothrombotic disease is J-shaped. Rates increase for fasting plasma glucose levels >100 mg/dL and also for those with low fasting glucose levels. These findings may carry important implications for prevention strategies.
Culture Contact and Valuation: Early German Buddhists and the Creation of a ‘Buddhism in Protestant Shape’
Authors: Baumann Martin
Published: August 2004

This paper handles the question concerning the factors that control the degree of adaptability of a transplanted religion spread in a culturally alien context. It will be argued that the assumed superiority of both one's religion and one's culture are decisive factors for the willingness to adapt or to refuse adaptation. The theoretical issues will be illustrated by the adoption of Buddhism by its early German followers. Thus, the paper gives a brief survey of the historical development of the adoption of Buddhism in Germany. Characteristics of the early phases will be outlined as well as the state of affairs of Buddhism in Germany in the 1990's. Most remarkable is Buddhism's rapid growth which increased the number of Buddhist centres and groups fivefold since the mid 1970's.On the basis of this historic description a particular line of interpreting Buddhist teachings, that of a rational understanding, is outlined. The analysis of this adoption of Buddhism seeks to show that early German Buddhists interpreted and moulded Buddhist teachings in such a way as to present it as being in high conformity with Western morals and culture. This high degree of adapting Buddhist teachings led to an interpretation which can be characterized as a ‘Buddhism in Protestant shape.’ Buddhism was used as a means of protest against the dominant religion, that of Christianity, but at the same time its proponents took over many forms and characteristics of the religion criticized most heavily.
The Iconoclasm of Obeisance: Protestant Images of Chinese Religion and the Catholic Church
Authors: Reinders Eric
Published: August 2004

Western studies of Buddhism emphasize doctrine and meditation, but almost completely ignore devotional practice. Yet, obeisance to Buddha is the primary religious practice of the majority of Asian Buddhists. To account for this disparity, I explore the history of Protestant attitudes towards bowing. In English and German anti-Catholic polemics (and Catholic responses), Chinese and Catholic obeisance are conflated, the lowness of their prostrations emphasized, in contrast to the erectness of Protestant posture in worship. I survey two important encyclopedias of religion (Hastings' of 1914 and Eliade's of 1987), and the work of one of the founders of Sociology, Herbert Spencer, to show the persistance of these perspectives on obeisance.Eighteenth and nineteenth-century Protestants worked to challenge the Jesuit representation of China as enlightened and originally monotheistic. Chinese religiosity was depicted as passive, lazy, infantile, and mindless, lacking any coherent doctrinal system. At times, the Protestant narrative of Christian history (from original pure community to institutional degeneration into idolatry) was superimposed on Chinese history. Obeisance itself was taken as sufficient proof of idolatry, the deceptive “holy mummeries” of Chinese/Catholic ritual.These tensions came to a head when King George III of England sent Lord Macartney to have an audience with emperor Qianlong of China, and Macartney refused to bow. A brief analysis of this well-documented mission reveals the confluence of religious, political, bodily, and gender dimensions. Recent treatments of that mission have missed the Protestant/Catholic dimensions of the issue.Finally I suggest possible extentions of the theoretical concerns of this paper.
Histology of the Torn Meniscus: A Comparison of Histologic Differences in Meniscal Tissue between Tears in Anterior Cruciate LigamentIntact and Anterior Cruciate LigamentDeficient Knees
Authors: Meister Keith , Indelicato Peter A. , Spanier Suzanne , Franklin John , Batts Joel
Published: August 2004

Purpose

The purpose of this case control study was to evaluate possible preexisting structural differences between torn menisci in anterior cruciate ligament–intact and anterior cruciate ligament–deficient knees.

Materials and Methods

Subjects were prospectively enrolled into the study from new patient referrals to the orthopaedic clinic. Forty-four meniscal specimens were retrieved during routine arthroscopy. The anterior cruciate ligament–deficient group included 24 patients (15 men and 9 women, average age of 26.5 years, SD = 9.5) with 24 acute, displaced, longitudinal, bucket-handle tears of the medial meniscus in unstable, anterior cruciate ligament–deficient knees. The anterior cruciate ligament–intact group included 20 patients (14 men and 6 women, average age of 30.4 years, SD = 13.4) with similar tears in anterior cruciate ligament–intact knees. Longitudinal and transverse section specimens were stained with hematoxylin and eosin and safranin O, divided into zones based on proximity to the tear, and graded on safranin O uptake or tissue composition.

Results

Descriptive statistics and χ2 analyses were used to assess differences between groups within each zone. Significant differences (P < .05) were observed between anterior cruciate ligament–deficient and anterior cruciate ligament–intact specimens stained with hematoxylin and eosin in zone 3 for both transverse and longitudinal cuts. Significant differences were not found between anterior cruciate ligament–deficient and anterior cruciate ligament–intact specimens stained with safranin O.

Conclusion

Longitudinal meniscal tears occurring in anterior cruciate ligament–intact knees may result from early degenerative disease processes. Attempted repair of this diseased tissue may fail to have a positive effect on long-term preservation of the meniscus.
Differential regulation of P-selectin ligand expression in naive versus memory CD4+ T cells: evidence for epigenetic regulation of involved glycosyltransferase genes
Authors: Syrbe Uta , Jennrich Silke , Schottelius Arndt , Richter Anne , Radbruch Andreas , Hamann Alf
Published: August 2004

Lymphocytes are targeted to inflamed sites by specific “homing” and chemokine receptors. Most of them, including ligands for P- and E-selectin, are absent from naive CD4+ T cells and become induced after activation and differentiation in effector/memory cells. Polarized effector cells are characterized by the rapid production of distinct cytokines upon restimulation. Their cytokine memory is in part controlled by epigenetic imprinting during differentiation. Here we ask whether a similar mechanism could regulate selectin ligand expression, mediating entry into inflamed sites, notably within the skin. We report that acquisition of selectin ligands by naive but not memory CD4+ cells depends on progression through the G1/S phase of the cell cycle—a phase susceptible to modification of the chromatin structure. Cell-cycle arrest prevented transcriptional activation of glycosyltransferases involved in the generation of selectin ligands, suggesting that progression through the cell cycle is required to unlock their genes. Artificial DNA demethylation strongly increased the frequency of selectin ligand-expressing cells, suggesting that DNA methylation keeps transferase genes inaccessible in naive T cells. Due to these findings we propose that selectin-dependent inflammation-seeking properties are imprinted by epigenetic modifications upon T-cell differentiation into effector cells.
Epinephrine acts through erythroid signaling pathways to activate sickle cell adhesion to endothelium via LW-αvβ3 interactions
Authors: Zennadi Rahima , Hines Patrick C. , De Castro Laura M. , Cartron Jean-Pierre , Parise Leslie V. , Telen Marilyn J.
Published: August 2004

The possible role of physiologic stress hormones in enhancing adhesion of sickle erythrocytes (SS RBCs) to endothelial cells (ECs) in sickle cell disease (SCD) has not been previously explored. We have now found that up-regulation of intracellular cyclic adenosine monophosphate (cAMP)–dependent protein kinase A (PKA) by epinephrine significantly increased sickle but not normal erythrocyte adhesion to both primary and immortalized ECs. Inhibition of serine/threonine phosphatases also enhanced sickle erythrocyte adhesion at least partially through a PKA-dependent mechanism. Adhesion was mediated through LW (intercellular adhesion molecule-4 [ICAM-4], CD242) blood group glycoprotein, and immunoprecipitation studies showed that LW on sickle but not on normal erythrocytes undergoes increased PKA-dependent serine phosphorylation as a result of activation. The major counter receptor for LW was identified as the αvβ3 integrin on ECs. These data suggest that adrenergic hormones such as epinephrine may initiate or exacerbate vaso-occlusion and thus contribute to the association of vaso-occlusive events with physiologic stress.
Absence of clinical GVHD and the in vivo induction of regulatory T cells after transplantation of facilitating cells
Authors: Colson Yolonda L. , Christopher Kenneth , Glickman Jonathan , Taylor Kendra N. , Wright Renee , Perkins David L.
Published: August 2004

Graft-versus-host disease (GVHD) and failure of engraftment limit clinical bone marrow transplantation (BMT) to patients with closely matched donors. Engraftment failure of purified allogeneic hematopoietic stem cells (HSCs) has been decreased in various BMT models by including donor BM–derived CD8+/αβγδTCR- facilitating cells (FCs) or CD8+/αβTCR+ T cells in the BM inoculum. To aggressively investigate the GVHD potential of these donor CD8+ populations, a purified cell model of lethal GVHD was established in a murine semiallogeneic parent → F1 combination. Lethally irradiated recipients were reconstituted with purified donor HSCs alone or in combination with splenic T cells (TSP), BM-derived T cells (TBM), or the FC population. In marked contrast to the lethal GVHD present in recipients of HSCs plus TSP or CD8+ TBM, recipients of donor HSC+FC inocula did not exhibit significant clinical or histologic evidence of GVHD. Instead, HSC+FC recipients were characterized by increased splenocyte expression of transforming growth factor-β (TGF-β) and the induction of the regulatory T-cell genes CTLA4, GITR, and FoxP3. These findings suggest that the FCs, which express a unique FCp33-TCRβ heterodimer in place of αβTCR, permits HSC alloengraftment and prevents GVHD through the novel approach of regulatory T-cell induction in vivo.
Antiproliferative activity of a humanized anti-CD74 monoclonal antibody, hLL1, on B-cell malignancies
Authors: Stein Rhona , Qu Zhengxing , Cardillo Thomas M. , Chen Susan , Rosario Adriane , Horak Ivan D. , Hansen Hans J. , Goldenberg David M.
Published: August 2004

The humanized anti-CD74 monoclonal antibody (mAb) hLL1 is under evaluation as a therapeutic agent. The effects of hLL1—at times in comparison with the CD20 mAb rituximab—were assessed on non-Hodgkin lymphoma (NHL) and multiple myeloma (MM) cell lines and in tumor-bearing SCID mice. In vitro, hLL1 caused growth inhibition and induction of apoptosis in B-cell lines when cross-linked with an antihuman immunoglobulin G (IgG) second antibody. The sensitivity profile of the cell lines was different for hLL1 and rituximab, and antiproliferative activity was augmented when the 2 mAbs were combined. Unlike rituximab, hLL1 did not induce antibody-dependent cellular cytotoxicity or complement-mediated cytotoxicity. In xenograft models of NHL and MM, treatment with hLL1 yielded significant survival benefits without cross-linking agents. Efficacy was greater in the MM model, in which median survival time was increased more than 4.5-fold. Thus, hLL1 has therapeutic potential as a naked mAb for B-cell malignancies because of high antigen expression on malignant cells, specifically MM, with limited expression on normal tissue, and because of its antiproliferative activity. Further, hLL1 may be a therapeutic candidate for rituximab-resistant disease because the 2 antibodies apparently act through distinct mechanisms and exhibit different expression and sensitivity profiles, and activity can be augmented when the mAbs are combined.
Distinct types of primary cutaneous large B-cell lymphoma identified by gene expression profiling
Authors: Hoefnagel Juliette J. , Dijkman Remco , Basso Katia , Jansen Patty M. , Hallermann Christian , Willemze Rein , Tensen Cornelis P. , Vermeer Maarten H.
Published: August 2004

In the European Organization for Research and Treatment of Cancer (EORTC) classification 2 types of primary cutaneous large B-cell lymphoma (PCLBCL) are distinguished: primary cutaneous follicle center cell lymphomas (PCFCCL) and PCLBCL of the leg (PCLBCL-leg). Distinction between both groups is considered important because of differences in prognosis (5-year survival > 95% and 52%, respectively) and the first choice of treatment (radiotherapy or systemic chemotherapy, respectively), but is not generally accepted. To establish a molecular basis for this subdivision in the EORTC classification, we investigated the gene expression profiles of 21 PCLBCLs by oligonucleotide microarray analysis. Hierarchical clustering based on a B-cell signature (7450 genes) classified PCLBCL into 2 distinct subgroups consisting of, respectively, 8 PCFCCLs and 13 PCLBCLsleg. PCLBCLs-leg showed increased expression of genes associated with cell proliferation; the proto-oncogenes Pim-1, Pim-2, and c-Myc; and the transcription factors Mum1/IRF4 and Oct-2. In the group of PCFCCL high expression of SPINK2 was observed. Further analysis suggested that PCFCCLs and PCLBCLs-leg have expression profiles similar to that of germinal center B-cell–like and activated B-cell–like diffuse large B-cell lymphoma, respectively. The results of this study suggest that different pathogenetic mechanisms are involved in the development of PCFCCLs and PCLBCLs-leg and provide molecular support for the subdivision used in the EORTC classification.
Mechanisms of WASp-mediated hematologic and immunologic disease
Authors: Burns Siobhan , Cory Giles O. , Vainchenker William , Thrasher Adrian J.
Published: August 2004

The Wiskott-Aldrich syndrome protein (WASp) is a key regulator of actin polymerization in hematopoietic cells. The dynamic nature of cytoskeletal changes during a variety of cellular processes demands complex mechanisms for coordinated integration of input signals, precise localization within the cell, and regulated activation of the Arp2/3 complex. Mutations in the Wiskott-Aldrich syndrome gene either inhibit or dysregulate normal WASp function, resulting in clinical diseases with complex and disparate phenotypes. This review highlights recent advances that have enhanced our understanding of the mechanisms by which these molecular defects cause hematologic and immunologic disease.
Adoptive immunotherapy of BCR-ABL–induced chronic myeloid leukemia–like myeloproliferative disease in a murine model
Authors: Krause Daniela S. , Van Etten Richard A.
Published: August 2004

Donor leukocyte infusion (DLI) can induce graft-versus-leukemia (GvL) reactions in patients with chronic myeloid leukemia (CML) relapsing after allogeneic bone marrow transplantation (BMT), but the mechanisms of the antileukemic effect of DLI are unknown, and the procedure is complicated by graft-versus-host disease (GvHD) and graft failure. Here, we adapted a murine retroviral BMT model of Philadelphia+ leukemia by combining allogeneic bone marrow (BM) from C57Bl/6 (H-2b) mice with BCR-ABL–transduced Balb/c (H-2d) BM, inducing mixed chimerism and myeloproliferative disease in recipients resembling relapse of CML following allogeneic BMT. Infusions of allogeneic splenocytes eliminated BCR-ABL–induced CML-like disease in the majority of mixed chimeras, with significant GvL effects mediated by both CD4+ and CD4- cells. BCR-ABL–induced acute B-lymphoblastic leukemia was also eradicated by DLI in major histocompatibility complex (MHC)–mismatched chimeras. Most DLI-treated mice converted to full allogeneic chimerism but succumbed frequently to GvHD or graft failure. When MHC-matched B10.D2 (H-2d) mice were the allogeneic donors, CML-like disease was more resistant to DLI. These results suggest that depletion of CD8+ cells from DLI could impair GvL against CML, while increased MHC disparity between donor and recipient may improve the responsiveness of Philadelphia+ B-lymphoblastic leukemia to DLI.
Design, implementation and evaluation of a practical pseudoknot folding algorithm based on thermodynamics
Authors: Reeder Jens , Giegerich Robert
Published: August 2004

Background

The general problem of RNA secondary structure prediction under the widely used thermodynamic model is known to be NP-complete when the structures considered include arbitrary pseudoknots. For restricted classes of pseudoknots, several polynomial time algorithms have been designed, where the O(n6)time and O(n4) space algorithm by Rivas and Eddy is currently the best available program.

Results

We introduce the class of canonical simple recursive pseudoknots and present an algorithm that requires O(n4) time and O(n2) space to predict the energetically optimal structure of an RNA sequence, possible containing such pseudoknots. Evaluation against a large collection of known pseudoknotted structures shows the adequacy of the canonization approach and our algorithm.

Conclusions

RNA pseudoknots of medium size can now be predicted reliably as well as efficiently by the new algorithm.
P2 receptor mRNA expression profiles in human lymphocytes, monocytes and CD34+ stem and progenitor cells
Authors: Wang Lingwei , Jacobsen Sten Eirik W , Bengtsson Anders , Erlinge David
Published: August 2004

Background

Extracellular nucleotides (ATP, ADP, UTP and UDP) exert a wide range of biological effects in blood cells mediated by multiple ionotropic P2X receptors and G protein-coupled P2Y receptors. Although pharmacological experiments have suggested the presence of several P2 receptor subtypes on monocytes and lymphocytes, some results are contradictory. Few physiological functions have been firmly established to a specific receptor subtype, partly because of a lack of truly selective agonists and antagonists. This stimulated us to investigate the expression of P2X and P2Y receptors in human lymphocytes and monocytes with a newly established quantitative mRNA assay for P2 receptors. In addition, we describe for the first time the expression of P2 receptors in CD34+ stem and progenitor cells implicating a potential role of P2 receptors in hematopoietic lineage and progenitor/stem cell function.

Results

Using a quantitative mRNA assay, we assessed the hypothesis that there are specific P2 receptor profiles in inflammatory cells. The P2X4 receptor had the highest expression in lymphocytes and monocytes. Among the P2Y receptors, P2Y12 and P2Y2 had highest expression in lymphocytes, while the P2Y2 and P2Y13 had highest expression in monocytes. Several P2 receptors were expressed (P2Y2, P2Y1, P2Y12, P2Y13, P2Y11, P2X1, P2X4) in CD34+ stem and progenitor cells.

Conclusions

The most interesting findings were the high mRNA expression of P2Y12 receptors in lymphocytes potentially explaining the anti-inflammatory effects of clopidogrel, P2Y13 receptors in monocytes and a previously unrecognised expression of P2X4 in lymphocytes and monocytes. In addition, for the first time P2 receptor mRNA expression patterns was studied in CD34+ stem and progenitor cells. Several P2 receptors were expressed (P2Y2, P2Y1, P2Y12, P2Y13, P2Y11, P2X1, P2X4), indicating a role in differentiation and proliferation. Thus, it is possible that specific antibodies to P2 receptors could be used to identify progenitors for monocytes, lymphocytes and megakaryocytes.
Elevated expression of MMP-13 and TIMP-1 in head and neck squamous cell carcinomas may reflect increased tumor invasiveness
Authors: Culhaci Nil , Metin Kubilay , Copcu Eray , Dikicioglu Emel
Published: August 2004

Background

Matrix metalloproteinases [MMPs], which degrade the extracellular matrix, play an important role in the invasion and metastasis of squamous cell carcinomas. One MMP, MMP-13, is thought to play a central role in MMP activation. The purpose of this study was to investigate MMP-13 and TIMP-1 expression in squamous cell carcinomas of the head and neck and to relate these levels of expression to histologic patterns of invasion.

Methods

This study included T1 lesions obtained via biopsy from the larynx, tongue, and skin/mucosa of 78 patients with head and neck squamous cell carcinomas. The relationship between expression of MMP-13 and TIMP-1 and the mode of tumor invasion [MI] was evaluated immunohistochemically, using breast carcinoma tissue as a positive control.

Results

Increased expression was observed in highly invasive tumors, as reflected by the significant correlation between the degree of staining for MMP-13 or TIMP-1 and MI grade [p < 0.05]. There was no significant relationship between the degree of staining for MMP-13 or TIMP-1 and patient age, sex, tumor site, or tumor histologic grade. In addition, levels of staining for MMP-13 did not correlate with levels of staining for TIMP-1.

Conclusion

The expression of MMP-13 and TIMP-1 appears to play an important role in determining the invasive capacity of squamous cell carcinomas of the head and neck. Whereas additional studies are needed to confirm these findings, evaluating expression of these MMPs in small biopsy samples may be useful in determining the invasive capacity of these tumors at an earlier stage.
Corneal topographic changes following retinal surgery
Authors: Sinha Rajesh , Sharma Namrata , Verma Lalit , Pandey RM , Vajpayee Rasik B
Published: August 2004

Background

To study the effect of retinal/ vitreoretinal surgeries on corneal elevations.

Methods

Patients who underwent retinal/ vitreoretinal surgeries were divided into 3 groups. Scleral buckling was performed in 11 eyes (Group 1). In 8 (25%) eyes, vitreoretinal surgery was performed along with scleral buckling (Group 2). In 12 eyes, pars plana vitrectomy was performed for vitreous hemorrhage (Group 3). An encircling element was used in all the eyes. The parameters evaluated were best-corrected visual acuity (BCVA), change in axial length, and corneal topographic changes on Orbscan topography system II, preoperative and at 12 weeks following surgery.

Results

There was a statistically significant increase in anterior corneal elevation in all the three groups after surgery (p = 0.003, p = 0.008 & p = 0.003 respectively). The increase in posterior corneal elevation was highly significant in all the three groups after surgery (p = 0.0000, p = 0.0001 & p = 0.0001 respectively). The increase in the posterior corneal elevation was more than the increase in the anterior elevation and was significant statistically in all the three groups (group I: p = 0.02; group II: p = 0.01; group III: p = 0.008).

Conclusions

Retinal/ vitreoretinal surgeries cause a significant increase in the corneal elevations and have a greater effect on the posterior corneal surface.
Fitness benefits of trypsin proteinase inhibitor expression in Nicotiana attenuata are greater than their costs when plants are attacked.
Authors: Zavala Jorge A , Baldwin Ian T
Published: August 2004

Background

The commonly invoked cost-benefit paradigm, central to most of functional biology, explains why one phenotype cannot be optimally fit in all environments; yet it is rarely tested. Trypsin proteinase inhibitors (TPIs) expression in Nicotiana attenuata is known to decrease plant fitness when plants compete with unattacked conspecifics that do not produce TPIs and also to decrease the performance of attacking herbivores.

Results

In order to determine whether the putative benefits of TPI production outweigh its cost, we transformed N. attenuata to silence endogenous TPI production or restore it in a natural mutant that was unable to produce TPIs. We compared the lifetime seed production of N. attenuata genotypes of the same genetic background with low or no TPI to that of genotypes with high TPI levels on which M. sexta larvae were allowed to feed freely. Unattacked low TPI-producing genotypes produced more seed capsules than did plants with high TPI levels. Caterpillar attack reduced seed capsule production in all genotypes and reversed the pattern of seed capsule production among genotypes. M. sexta larvae attacking genotypes with high TPI activity consumed more TPI, less protein, and move later to the young leaves. Larval masses were negatively correlated (R2 = 0.56) with seed capsule production per plant.

Conclusions

Our results demonstrate that the fitness benefits of TPI production outweigh their costs in greenhouse conditions, when plants are attacked and that despite the ongoing evolutionary interactions between plant and herbivore, TPI-mediated decreases in M. sexta performance translates into a fitness benefit for the plant.
Racial variations in processes of care for patients with community-acquired pneumonia
Authors: Mortensen Eric M , Cornell John , Whittle Jeff
Published: August 2004

Background

Patients hospitalized with community acquired pneumonia (CAP) have a substantial risk of death, but there is evidence that adherence to certain processes of care, including antibiotic administration within 8 hours, can decrease this risk. Although national mortality data shows blacks have a substantially increased odds of death due to pneumonia as compared to whites previous studies of short-term mortality have found decreased mortality for blacks. Therefore we examined pneumonia-related processes of care and short-term mortality in a population of patients hospitalized with CAP.

Methods

We reviewed the records of all identified Medicare beneficiaries hospitalized for pneumonia between 10/1/1998 and 9/30/1999 at one of 101 Pennsylvania hospitals, and randomly selected 60 patients at each hospital for inclusion. We reviewed the medical records to gather process measures of quality, pneumonia severity and demographics. We used Medicare administrative data to identify 30-day mortality. Because only a small proportion of the study population was black, we included all 240 black patients and randomly selected 720 white patients matched on age and gender. We performed a resampling of the white patients 10 times.

Results

Males were 43% of the cohort, and the median age was 76 years. After controlling for potential confounders, blacks were less likely to receive antibiotics within 8 hours (odds ratio with 95% confidence interval 0.6, 0.4–0.97), but were as likely as whites to have blood cultures obtained prior to receiving antibiotics (0.7, 0.3–1.5), to have oxygenation assessed within 24 hours of presentation (1.6, 0.9–3.0), and to receive guideline concordant antibiotics (OR 0.9, 0.6–1.7). Black patients had a trend towards decreased 30-day mortality (0.4, 0.2 to 1.0).

Conclusion

Although blacks were less likely to receive optimal care, our findings are consistent with other studies that suggest better risk-adjusted survival among blacks than among whites. Further study is needed to determine why this is the case.
Attenuation of dengue virus infection by adeno-associated virus-mediated siRNA delivery
Authors: Zhang Weidong , Singam Rajeswari , Hellermann Gary , Kong Xiaoyuan , Juan Homero San , Lockey Richard F , Wu Shuen-Ju , Porter Kevin , Mohapatra Shyam S
Published: August 2004

Background

The need for safe and effective treatment of dengue virus (DEN), a class A agent that causes dengue hemorrhagic fever/dengue shock syndrome, has been a critical global priority. An effective vaccine for DEN is not yet available. In this study the possibility of attenuating DEN infection using adeno-associated virus (AAV)-encoded short interfering RNAs (siRNA) was examined in Vero cells and human dendritic cells (DCs).

Methods

A cassette encoding siRNA targeted to a 3' untranslated sequence common to all DEN serotypes was designed and tested for its ability to attenuate DEN infection by use of AAV delivery.

Results

Vero cells or DCs infected with AAV-siRNA showed a significant, dose-dependent reduction in DEN infection. Treatment of DCs with AAV-siRNA also decreased the DEN-induced apoptosis of DCs and did not induce significant inflammation.

Conclusion

These results demonstrate that AAV-mediated siRNA delivery is capable of reducing DEN infection in cells and may be useful in decreasing DEN replication in humans.
Conflicts of interest in translational research
Authors: Parks Malcolm R , Disis Mary L
Published: August 2004

Translational research requires a team approach to scientific inquiry and product development. Translational research teams consist of basic and clinical scientists who can be members of both academic and industrial communities. The conception, pre-clinical testing, and clinical evaluation of a diagnostic or therapeutic approach demands an intense interaction between investigators with diverse backgrounds. As the barriers between industry and academia are removed, issues of potential conflict of interest become more complex. Translational researchers must become aware of the situations which constitute conflict of interest and understand how such conflicts can impact their research programs. Finally, the translational research community must participate in the dialogue ongoing in the public and private sectors and help shape the rules that will govern conflicts that arise during the evolution of their research programs.
Discovery of estrogen receptor α target genes and response elements in breast tumor cells
Authors: Lin Chin-Yo , Ström Anders , Vega Vinsensius Berlian , Li Kong Say , Li Yeo Ai , Thomsen Jane S , Chan Wan Ching , Doray Balraj , Bangarusamy Dhinoth K , Ramasamy Adaikalavan , Vergara Liza A , Tang Suisheng , Chong Allen , Bajic Vladimir B , Miller Lance D , Gustafsson Jan-Åke , Liu Edison T
Published: August 2004

Background

Estrogens and their receptors are important in human development, physiology and disease. In this study, we utilized an integrated genome-wide molecular and computational approach to characterize the interaction between the activated estrogen receptor (ER) and the regulatory elements of candidate target genes.

Results

Of around 19,000 genes surveyed in this study, we observed 137 ER-regulated genes in T-47D cells, of which only 89 were direct target genes. Meta-analysis of heterogeneous in vitro and in vivo datasets showed that the expression profiles in T-47D and MCF-7 cells are remarkably similar and overlap with genes differentially expressed between ER-positive and ER-negative tumors. Computational analysis revealed a significant enrichment of putative estrogen response elements (EREs) in the cis-regulatory regions of direct target genes. Chromatin immunoprecipitation confirmed ligand-dependent ER binding at the computationally predicted EREs in our highest ranked ER direct target genes, NRIP1, GREB1 and ABCA3. Wider examination of the cis-regulatory regions flanking the transcriptional start sites showed species conservation in mouse-human comparisons in only 6% of predicted EREs.

Conclusions

Only a small core set of human genes, validated across experimental systems and closely associated with ER status in breast tumors, appear to be sufficient to induce ER effects in breast cancer cells. That cis-regulatory regions of these core ER target genes are poorly conserved suggests that different evolutionary mechanisms are operative at transcriptional control elements than at coding regions. These results predict that certain biological effects of estrogen signaling will differ between mouse and human to a larger extent than previously thought.
Septopreoptic μ Opioid Receptor Mediation of Hindbrain Glucoprivic Inhibition of Reproductive Neuroendocrine Function in the Female Rat
Authors: Singh Sushma R. , Briski Karen P.
Published: August 2004

Central glucostasis is a critical monitored variable in neuroendocrine regulation of pituitary LH secretion. Glucoprivic signals originating within the caudal hindbrain suppress LH. Septopreoptic μ opioid receptors (μ-R) function within neural pathways maintaining basal LH levels and mediate the effects of diverse physiological stimuli on hormone release. To identify potential sites in the septopreoptic area where ligand neuromodulatory actions may occur in response to hindbrain glucoprivic signaling, the present studies evaluated the distribution of μ-R-immunoreactive (-ir) neurons in the septopreoptic area that are genomically activated in response to caudal fourth ventricular (CV4) delivery of the glucose antimetabolite, 5-thioglucose (5TG). The effects of lateral ventricular pretreatment with the selective μ-R antagonist, d-Phe-Cys-Tyr-d-Trp-Orn-Thr-Pen-Thr-NH2 (CTOP), on LH secretory and GnRH neuronal transcriptional responses to hindbrain glucoprivation were also evaluated. Estradiol benzoate- and progesterone-primed, ovariectomized female rats were treated by CV4 administration of 5TG or the vehicle, saline, at the onset of the afternoon LH surge. The inhibitory effects of hindbrain glucoprivation on mean plasma LH levels as well as colabeling of rostral preoptic GnRH neurons for Fos-ir were attenuated in animals pretreated by lateral ventricular delivery of CTOP. Dual immunocytochemical labeling for septopreoptic μ-R-ir and Fos-ir demonstrated a robust induction of Fos expression by receptor-positive neurons within discrete septopreoptic sites in response to CV4 5TG, a genomic response that was diminished by CTOP pretreatment. The current studies provide novel evidence for the transcriptional activation of neuroanatomically characterized, μ-R-expressing neurons by decreased hindbrain glucose utilization and show that the functional status of μ-R is critical for maximal induction of the Fos stimulus-transcription cascade in these cells by central glucoprivic signaling. The finding that receptor antagonist-mediated suppression of this genomic response is correlated with increased reproductive neuroendocrine output supports a role for these discrete μ-R-expressing neuron populations as substrates for ligand regulatory effects on the GnRH-pituitary LH axis during neuroglucopenia.
Identification and Characterization of the Zebrafish and Fugu Genes Encoding Tuberoinfundibular Peptide 39
Authors: Papasani Madhusudhan R. , Gensure Robert C. , Yan Yi-Lin , Gunes Yasemin , Postlethwait John H. , Ponugoti Bhaskar , John Markus R. , Jüppner Harald , Rubin David A.
Published: August 2004

Although the PTH type 2 receptor (PTH2R) has been isolated from mammals and zebrafish, only its mammalian agonist, tuberoinfundibular peptide 39 (TIP39), has been characterized thus far. To determine whether zebrafish TIP39 (zTIP39) functions similarly with the zebrafish PTHR (zPTH2R) and human PTH2Rs and to determine its tissue-specific expression, fugu (Takifugu rubripes) and zebrafish (Danio rerio) genomic databases were screened with human TIP39 (hTIP39) sequences. A single TIP39 gene was identified for each fish species, which showed significant homology to mammalian TIP39. Using standard molecular techniques, we isolated cDNA sequences encoding zTIP39. The fugu TIP39 precursor was encoded by a gene comprising at least three exons. It contained a hydrophobic signal sequence and a predicted prosequence with a dibasic cleavage site, similar to that found in mammalian TIP39 ligands. Phylogenetic analyses suggested that TIP39 forms the basal group from which PTH and PTHrP have been derived. Functionally, subtle differences in potency could be discerned between hTIP39 and zTIP39. The human PTH2R and zPTH2R were stimulated slightly better by both hTIP39 and zTIP39, whereas zTIP39 had a higher potency at a previously isolated zPTH2R splice variant. Whole-mount in situ hybridization of zebrafish revealed strong zTIP39 expression in the region of the hypothalamus and in the heart of 24- and 48-h-old embryos. Similarly, zPTH2R expression was highly expressed throughout the brain of 48- and 72-h-old embryos. Because the mammalian PTH2R was also most abundantly expressed in these tissues, the TIP39-PTH2R system may serve conserved physiological roles in mammals and fishes.
Inhibition of Hepatic Gluconeogenesis and Enhanced Glucose Uptake Contribute to the Development of Hypoglycemia in Mice Bearing Interleukin-1β- Secreting Tumor
Authors: Metzger Shulamit , Nusair Samir , Planer David , Barash Varda , Pappo Orit , Shilyansky Joel , Chajek-Shaul Tova
Published: August 2004

Mice bearing IL-1β-secreting tumor were used to study the chronic effect of IL-1β on glucose metabolism. Mice were injected with syngeneic tumor cells transduced with the human IL-1β gene. Serum IL-1β levels increased exponentially with time. Secretion of IL-1β from the developed tumors was associated with decreased food consumption, reduced body weight, and reduced blood glucose levels. Body composition analysis revealed that IL-1β caused a significant loss in fat tissue without affecting lean body mass and water content. Hepatic phosphoenolpyruvate carboxykinase and glucose-6-phosphatase activities and mRNA levels of these enzymes were reduced, and 2-deoxy-glucose uptake by peripheral tissues was enhanced. mRNA levels of glucose transporters (Gluts) in the liver were determined by real-time PCR analysis. Glut-3 mRNA levels were up-regulated by IL-1β. Glut-1 and Glut-4 mRNA levels in IL-1β mice were similar to mRNA levels in pair-fed mice bearing nonsecreting tumor. mRNA level of Glut-2, the major Glut of the liver, was down-regulated by IL-1β. We concluded that both decreased glucose production by the liver and enhanced glucose disposal lead to the development of hypoglycemia in mice bearing IL-1β-secreting tumor. The observed changes in expression of hepatic Gluts that are not dependent on insulin may contribute to the increased glucose uptake.
Free Fatty Acids and Cytokines Induce Pancreatic β-Cell Apoptosis by Different Mechanisms: Role of Nuclear Factor-κB and Endoplasmic Reticulum Stress
Authors: Kharroubi Ilham , Ladrière Laurence , Cardozo Alessandra K. , Dogusan Zeynep , Cnop Miriam , Eizirik Décio L.
Published: August 2004

Apoptosis is probably the main form of β-cell death in both type 1 diabetes mellitus (T1DM) and T2DM. In T1DM, cytokines contribute to β-cell destruction through nuclear factor-κB (NF-κB) activation. Previous studies suggested that in T2DM high glucose and free fatty acids (FFAs) are β-cell toxic also via NF-κB activation. The aims of this study were to clarify whether common mechanisms are involved in FFA- and cytokine-induced β-cell apoptosis and determine whether TNFα, an adipocyte-derived cytokine, potentiates FFA toxicity through enhanced NF-κB activation. Apoptosis was induced in insulinoma (INS)-1E cells, rat islets, and fluorescence-activated cell sorting-purified β-cells by oleate, palmitate, and/or cytokines (IL-1β, interferon-γ, TNFα). Palmitate and IL-1β induced a similar percentage of apoptosis in INS-1E cells, whereas oleate was less toxic. TNFα did not potentiate FFA toxicity in primary β-cells. The NF-κB-dependent genes inducible nitric oxide synthase and monocyte chemoattractant protein-1 were induced by IL-1β but not by FFAs. Cytokines activated NF-κB in INS-1E and β-cells, but FFAs did not. Moreover, FFAs did not enhance NF-κB activation by TNFα. Palmitate and oleate induced C/EBP homologous protein, activating transcription factor-4, and immunoglobulin heavy chain binding protein mRNAs, X-box binding protein-1 alternative splicing, and activation of the activating transcription factor-6 promoter in INS-1E cells, suggesting that FFAs trigger an endoplasmic reticulum (ER) stress response. We conclude that apoptosis is the main mode of FFA- and cytokine-induced β-cell death but the mechanisms involved are different. Whereas cytokines induce NF-κB activation and ER stress (secondary to nitric oxide formation), FFAs activate an ER stress response via an NF-κB- and nitric oxide-independent mechanism. Our results argue against a unifying hypothesis for the mechanisms of β-cell death in T1DM and T2DM.