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Publication
Journal: Theoretical And Applied Genetics
April/7/2004
Abstract
Two populations of single chromosome recombinant lines were used to map genes controlling flowering time on chromosome 5B of wheat, and one of the populations was also used to map a new frost resistance gene. Genetic maps were developed, mainly using microsatellite markers, and QTL analysis was applied to phenotypic data on the performance of each population collected from growth-room tests of flowering time and frost tolerance. Using a recombinant substitution-line mapping population derived from a cross between the substitution-line 'Chinese Spring' ('Cheyenne' 5B) and 'Chinese Spring' (CS), the gene Vrn-B1, affecting vernalization response, an earliness per se locus, Eps-5BL1, and a gene, Fr-B1, affecting frost resistance, were mapped. Using a 'Hobbit Sib' ('Chinese Spring' 5BL) x 'Hobbit Sib' recombinant substitution line mapping population, an earliness per se locus, Eps-5BL2 was mapped. The Vrn-B1 locus was mapped on the distal portion of the long arm of chromosome 5B, to a region syntenous with the segments of chromosomes 5A and 5D containing Vrn-A1 and Vrn-D1 loci, respectively. The two Eps-5BL loci were mapped close to the centromere with a 16-cM distance from each other, one in agreement with the position of a homoeologous locus previously mapped on chromosome 5H of barley, and suggested by the response of 'Chinese Spring' deletion lines. The Fr-B1 gene was mapped on the long arm of chromosome 5B, 40 cM from the centromeric marker. Previous comparative mapping data with rice chromosome 9 would suggest that this gene could be orthologous to the other Fr genes mapped previously by us on chromosomes 5A or 5D of wheat, although in a more proximal position. This study completes the mapping of these homoeoallelic series of vernalization requirement genes and frost resistance genes on the chromosomes of the homoeologous group 5 in wheat.
Publication
Journal: Molecular Plant-Microbe Interactions
February/3/2009
Abstract
In order to enter symbiosis with its legume partner, Sinorhizobium meliloti requires regulatory systems for the appropriate responses to its environment. For example, motility is required for the chemotactic movement of bacteria toward the compounds released by its host, and exopolysaccharides (EPS) are required for bacterial attachment to the root or for invasion of the infection thread. Previous research has shown that ExoR/ExoS/ChvI as well as the ExpR/Sin quorum-sensing system inversely regulate both motility and EPS production, although the regulation mechanisms were unknown. We were able to attribute the ExpR-mediated regulation of motility to the ability of ExpR to bind a DNA sequence upstream of visN when activated by N-acyl-homoserine lactone. Furthermore, MucR, previously characterized as a regulator of EPS production, also affected motility. MucR inhibited expression of rem encoding an activator of motility gene expression and, consequently, the expression of Rem-regulated genes such as flaF and flgG. Binding of MucR to the rem promoter region was demonstrated and a sequence motif similar to the previously identified MucR binding consensus was identified within this region. The swarming ability of S. meliloti Rm2011 was shown to depend on a functional ExpR/Sin quorum-sensing system and the production of both flagella and EPS. Finally, we propose a model for the coordination of motility and EPS synthesis in S. meliloti.
Publication
Journal: Journal of Immunology
June/20/2005
Abstract
Although PGE(2) is a potent inhibitor of fibroblast function, PGE(2) levels are paradoxically elevated in murine lungs undergoing fibrotic responses. Pulmonary fibroblasts from untreated mice expressed all four E prostanoid (<em>EP</em>) receptors for PGE(2). However, following challenge with the fibrogenic agent, bleomycin, fibroblasts showed loss of <em>EP</em>2 expression. Lack of <em>EP</em>2 expression correlated with an inability of fibroblasts from bleomycin-treated mice to be inhibited by PGE(2) in assays of proliferation or collagen synthesis and blunted cAMP elevations in response to PGE(2). PGE(2) was similarly unable to suppress proliferation or collagen synthesis in fibroblasts from <em>EP</em>2(-/-) mice despite expression of the other <em>EP</em> receptors. <em>EP</em>2(-/-), but not <em>EP</em>1(-/-) or <em>EP</em>3(-/-) mice, showed exaggerated fibrotic responses to bleomycin administration in vivo as compared with wild-type controls. <em>EP</em>2 loss on fibroblasts was verified in a second model of pulmonary fibrosis using FITC. Our results for the first time link <em>EP</em>2 receptor loss on fibroblasts following fibrotic lung injury to altered suppression by PGE(2) and thus identify a novel fibrogenic mechanism.
Publication
Journal: Cell Metabolism
September/19/2013
Abstract
Adult humans have about 25 trillion red blood cells (RBCs), and each second we recycle about 5 million RBCs by erythrophagocytosis (EP) in macrophages of the reticuloendothelial system. Despite the central role for EP in mammalian iron metabolism, the molecules and pathways responsible for heme trafficking during EP remain unknown. Here, we show that the mammalian homolog of HRG1, a transmembrane heme permease in C. elegans, is essential for macrophage iron homeostasis and transports heme from the phagolysosome to the cytoplasm during EP. HRG1 is strongly expressed in macrophages of the reticuloendothelial system and specifically localizes to the phagolysosomal membranes during EP. Depletion of Hrg1 in mouse macrophages causes attenuation of heme transport from the phagolysosomal compartment. Importantly, missense polymorphisms in human HRG1 are defective in heme transport. Our results reveal HRG1 as the long-sought heme transporter for heme-iron recycling in macrophages and suggest that genetic variations in HRG1 could be modifiers of human iron metabolism.
Publication
Journal: Science
April/19/2000
Abstract
Virulence of Vibrio cholerae depends on secretion of cholera toxin (CT), which is encoded within the genome of a filamentous phage, CTXphi. Release of CT is mediated by the extracellular protein secretion (eps) type II secretion system. Here, the outer membrane component of this system, EpsD, was shown to be required for secretion of the phage as well. Thus, EpsD plays a role both in pathogenicity and in horizontal transfer of a key virulence gene. Genomic analysis suggests that additional filamentous phages also exploit chromosome-encoded outer membrane channels.
Publication
Journal: Proceedings of the National Academy of Sciences of the United States of America
April/18/2001
Abstract
Trypanosoma brucei, the protozoan parasite causing sleeping sickness, is transmitted by a tsetse fly vector. When the tsetse takes a blood meal from an infected human, it ingests bloodstream form trypanosomes that quickly differentiate into procyclic forms within the fly's midgut. During this process, the parasite loses the 10(7) molecules of variant surface glycoprotein that formed its surface coat, and it develops a new coat composed of several million procyclin molecules. Procyclins, the products of a small multigene family, are glycosyl phosphatidylinositol-anchored proteins containing characteristic amino acid repeats at the C terminus [either <em>EP</em> (<em>EP</em> procyclin, a form of procyclin rich in Glu-Pro repeats) or GPEET (GPEET procyclin, a form of procyclin rich in Glu-Pro-Glu-Glu-Thr repeats)]. We have used a sensitive and accurate mass spectrometry method to analyze the appearance of different procyclins during the establishment of midgut infections in tsetse flies. We found that different procyclin gene products are expressed in an orderly manner. Early in the infection (day 3), GPEET2 is the only procyclin detected. By day 7, however, GPEET2 disappears and is replaced by several isoforms of glycosylated <em>EP</em>, but not the unglycosylated isoform <em>EP</em>2. Unexpectedly, we discovered that the N-terminal domains of all procyclins are quantitatively removed by proteolysis in the fly, but not in culture. These findings suggest that one function of the protease-resistant C-terminal domain, containing the amino acid repeats, is to protect the parasite surface from digestive enzymes in the tsetse fly gut.
Publication
Journal: Journal of Studies on Alcohol and Drugs
March/28/2007
Abstract
OBJECTIVE
The purpose of this study was to identify developmental trajectories of problem drinking from adolescence into young adulthood and to determine if alcohol use initiation experiences and family history of alcoholism, as well as their interactions, would predict trajectory group membership.
METHODS
Five waves of data were collected from respondents who were 12 years old at the time of recruitment to the Rutgers Health and Human Development Project and followed until age 31 (n = 438). A standardized measure of problem drinking (Rutgers Alcohol Problem Index) was used to develop trajectories with growth-mixture modeling. Differences across groups in first- use experience (age of onset, pleasantness of the experience, and feeling intoxicated), a family history of alcoholism, and gender were analyzed with chi-square and analysis of variance tests, and logistic regression analyses were used to estimate the odds of group membership.
RESULTS
Three trajectory groups of drinkers were identified: no or low problem (66.2%), adolescence-limited problem (ALP; 21.6%), and escalating problem (EP; 12.1%) drinkers. Age at drinking onset, feeling drunk during the first alcohol experience, and family history of alcoholism were associated with significantly greater odds of being in a problem trajectory group relative to the no or low problem trajectory. Early experiences did not differentiate the ALP and EP trajectories. None of the interactions was significantly associated with membership in any of the groups.
CONCLUSIONS
The levels and patterns of problem drinking during early to mid-adolescence point to a need for secondary prevention efforts that target problematic users in addition to the current emphasis on primary prevention of alcohol consumption. Prevention-based research may benefit from special focus on the meaning and consequences of self-perception of drunkenness when alcohol is first used.
Publication
Journal: Experimental Cell Research
November/4/2003
Abstract
Aberrant upregulation of COX-2 enzyme resulting in accumulation of PGE2 in a cancer cell environment is a marker for progression of many cancers, including breast cancer. Four subtypes of cell surface receptors (<em>EP</em>1, <em>EP</em>2, <em>EP</em>3, and <em>EP</em>4), which are coupled with different G-proteins, mediate PGE2 actions. Since migration is an essential step in invasion and metastasis, in the present study we defined the expression of <em>EP</em> receptors and their roles in migratory function of breast cancer cells of murine (C3L5) and human (MDA-MB-231 and MCF-7) origin. Highly metastatic C3L5 and MDA-MB-231 cells, found to be highly migratory in a Transwell migration assay, were shown to accumulate much higher levels of PGE2 in culture media in comparison with nonmetastatic and poorly migrating MCF-7 cells; the levels of PGF2alpha and 6-keto-PGF1alpha were low in all cases. The elevated PGE2 production by metastatic cancer cells was due to COX-2 activity since dual COX-1/2 inhibitor indomethacin and selective COX-2 inhibitor NS-398 equally suppressed both basal and inducible (by IFN-gamma/LPS or Ca2+-ionophores) PGE2 accumulation. RT-PCR analysis revealed that murine C3L5 cells expressed mRNA of <em>EP</em>1, <em>EP</em>3, and <em>EP</em>4 but not <em>EP</em>2 receptors. On the other hand, human MDA-MB-231 and MCF-7 cells expressed all the above receptors. High levels of expression of functional <em>EP</em>4 receptors coupled with Gs-protein was confirmed in C3L5 cells by biochemical assay showing a dose-dependent increase of intracellular cAMP synthesis in response to PGE2. <em>EP</em> receptor antagonists SC-19220, AH-6809, and AH-23848B, having highest affinity for <em>EP</em>1, <em>EP</em>1/<em>EP</em>2/DP, and <em>EP</em>4 receptors, respectively, variably inhibited migration of metastatic breast cancer cells. An autocrine PGE2-mediated migratory activity of these cells appeared to be associated predominantly with <em>EP</em>4 receptor-mediated signaling pathway, which uses cAMP as a second messenger. This conclusion is based on several observations: (1) selective <em>EP</em>4 antagonist AH-23848B effectively inhibited migration of both C3L5 and MDA-MB-231 cells in a dose-dependent manner; (2) exogenous PGE2 and <em>EP</em>4 agonist PGE1 alcohol increased migration of C3L5 cells; (3) forskolin, a potent activator of adenylate cyclase, as well as membrane-permeable analogues of cAMP (8-bromo-cAMP, dibutyryl-cAMP) stimulated migration of C3L5 cells; and (4) Rp-cAMPS, a selective protein kinase A inhibitor, reduced migration of C3L5 cells. Migration of poorly migratory MCF-7 cells remained unaffected with either PGE2 or <em>EP</em>4 antagonist. These findings are relevant for designing therapeutic strategies against breast cancer metastasis.
Publication
Journal: Biochemical Journal
April/14/2008
Abstract
Tissue macrophages play an essential role in iron recycling through the phagocytosis of senescent RBCs (red blood cells). Following haem catabolism by HO1 (haem oxygenase 1), they recycle iron back into the plasma through the iron exporter Fpn (ferroportin). We previously described a cellular model of EP (erythrophagocytosis), based on primary cultures of mouse BMDMs (bone-marrow-derived macrophages) and aged murine RBCs, and showed that EP induces changes in the expression profiles of Fpn and HO1. In the present paper, we demonstrate that haem derived from human or murine RBCs or from an exogenous source of haem led to marked transcriptional activation of the Fpn and HO1 genes. Iron released from haem catabolism subsequently stimulated the Fpn mRNA and protein expression associated with localization of the transporter at the cell surface, which probably promotes the export of iron into the plasma. These findings highlight a dual mechanism of Fpn regulation in BMDMs, characterized by early induction of the gene transcription predominantly mediated by haem, followed by iron-mediated post-transcriptional regulation of the exporter.
Publication
Journal: Journal of applied physiology: respiratory, environmental and exercise physiology
September/9/1982
Abstract
Six well-trained endurance athletes were studied to determine if submaximal treadmill exercise results in increased plasma levels of beta-endorphin/beta-lipotropin (Bh-Ep/Bh-LPH) immunoreactivity. Bh-Ep/Bh-LPH immunoreactivity was measured by radio immunoassay in plasma from six experienced runners before and after 30-min treadmill runs at a self-selected pace, 60 and 80% VO2 max, and a control experiment of 30 min rest. All tests were randomized and occurred during the same time of day for a given subject (0600--1500 h). Preexercise Bh-Ep/Bh-LPH values averaged between 10 and 20 pg/ml and increased two- to fivefold after each run. The increase was statistically significant (P less than 0.05) only after the 60% run when Bh-Ep/Bh-LPH increased to a mean of 58.3 pg/ml. A large individual variation in the Bh-Ep/Bh-LPH response to running was noted. Mood state and perceptual data were also collected, and no significant relationship with Bh-Ep/Bh-LPH was evident. These data suggest that the stress of treadmill running acts as a stimulus to greater Bh-Ep/Bh-LPH secretion, a reduction in its degradation, or a combination of these, which leads to increased levels of these ligands in venous blood. The physiological significance of these increased plasma levels is not clear.
Publication
Journal: Journal of Virology
June/10/2008
Abstract
In vivo electroporation (EP) has been shown to augment the immunogenicity of plasmid DNA vaccines, but its mechanism of action has not been fully characterized. In this study, we show that in vivo EP augmented cellular and humoral immune responses to a human immunodeficiency virus type 1 Env DNA vaccine in mice and allowed a 10-fold reduction in vaccine dose. This enhancement was durable for over 6 months, and re-exposure to antigen resulted in anamnestic effector and central memory CD8(+) T-lymphocyte responses. Interestingly, in vivo EP also recruited large mixed cellular inflammatory infiltrates to the site of inoculation. These infiltrates contained 45-fold-increased numbers of macrophages and 77-fold-increased numbers of dendritic cells as well as 2- to 6-fold-increased numbers of B and T lymphocytes compared to infiltrates following DNA vaccination alone. These data suggest that recruiting inflammatory cells, including antigen-presenting cells (APCs), to the site of antigen production substantially improves the immunogenicity of DNA vaccines. Combining in vivo EP with plasmid chemokine adjuvants that similarly recruited APCs to the injection site, however, did not result in synergy.
Publication
Journal: American Journal of Clinical Nutrition
February/7/1994
Abstract
In nutrition-intervention research, it is important to consider the sensitivity of dietary assessment instruments to the changes in nutrient intake or dietary behavior under study. This presentation describes a measure called "responsiveness," an index of an instrument's sensitivity to change. Illustrations of this measure are from two randomized dietary-intervention trials that targeted reductions in fat intake: the Women's Health Trial (WHT), a trial to test whether fat reduction would reduce the risk of breast cancer, and the Eating Patterns Study (EPS), a trial to evaluate a self-help booklet to promote dietary change. In the WHT, a 4-d diet record (FDDR) was only slightly more responsive to dietary change than was a food-frequency questionnaire (FFQ). In the EPS, a fat-related diet-habits questionnaire was most responsive, followed by an FDDR and an FFQ. These data suggest that short, inexpensive measures such as FFQs or questionnaires that assess dietary habits can be as responsive as multiple-day diet records. More research is needed on the relative responsiveness of dietary assessment tools. Intervention studies should include at least two types of dietary assessment tools and the relative validity, reliability, and responsiveness of these tools should be reported as part of the study outcome.
Publication
Journal: British Journal of Pharmacology
May/13/1986
Abstract
The agonist activities of a range of prostaglandin analogues on smooth muscle preparations sensitive to prostaglandin E2 (PGE2) have been investigated. When necessary thromboxane-like activity was eliminated using the thromboxane receptor antagonists EP 045 and EP 092. On the bullock iris sphincter, rat stomach fundus and guinea-pig trachea, (+/-) omega-tetranor-16-p-chlorophenoxy PGE2 (ICI 80205) and 16,16-dimethyl PGE2 were more active contractile agents than PGE2, whereas for relaxant activity on the cat trachea, guinea-pig trachea and dog hind limb arterial vessels in vivo the order of potency was reversed. 11-Deoxy PGE1 exhibited greater relaxant than contractile activity when compared to PGE2. Iloprost and 6a-carba-delta 6,6aPGI1 (potent mimetics of PGI2) showed high contractile activity on the PGE-sensitive preparations. PGI2 was less active and another potent PGI2 mimetic, ZK 96480, showed only very weak activity. When tested, the dibenzoxazepines SC 19220 and SC 25191 blocked the contractile actions of iloprost and 6a-carba-delta 6,6aPGI1 and those of PGE2 and 16,16-dimethyl PGE2 to similar extents. Each of the PGI2 analogues showed weak activity on the relaxant systems. On the proximal portion of the ascending colon of the rat, PGI2, iloprost, 6a-carba-delta 6,6aPGI1 and ZK 96480 always inhibited spontaneous activity at nanomolar concentrations. PGE2 and PGE1 showed weak contractile activity. The distal portion of the ascending colon was more responsive to the contractile action of PGE analogues: both iloprost and 6a-carba-delta 6,6aPGI1 showed evidence of contractile activity, whereas PGI2 and ZK 96480 always inhibited spontaneous activity. Evidence was obtained that the rat stomach fundus also contains a PGF receptor; (+/-) omega-tetranor-16-m-trifluoromethylphenoxy PGF2 alpha (ICI 81008) acted as a specific agonist. PGF2 alpha and its omega-tetranor-16-p-fluorophenoxy analogue produced a higher maximum response that ICI 81008 probably due to their additional agonist action at the PGE receptor. The data support the hypothesis that there are two subtypes of the PGE receptor. ZK 96480 has minimal activity on both receptor subtypes and appears to be a highly specific PGI2 mimetic.
Publication
Journal: Schizophrenia Research
February/28/2005
Abstract
Atypical antipsychotics (AAP) have been widely used for the management of patients with schizophrenia and other psychotic disorders since they were introduced during the past decade. AAP, as a class, have demonstrated a significant advantage over conventional antipsychotics in clinical efficacy and lower incidence of extrapyramidal symptoms (EPS) and tardive dyskinesia (TD). However, there have been numerous case reports, retrospective studies, epidemiological and clinical data suggesting that certain AAP may be associated with a greater risk of metabolic abnormalities than others, including weight gain, hyperlipidemia, and new-onset type 2 diabetes mellitus (DM) or diabetic ketoacidosis (DKA). In this article, we review and evaluate recent findings addressing the issue of glucose dysregulation associated with AAP therapy along with the recommendations with a recent consensus conference on this issue. Rational patient monitoring guidelines are also elucidated, particularly for high-risk populations that need more intensive scrutiny during treatment of AAP.
Publication
Journal: Psychopharmacology
February/12/2004
Abstract
BACKGROUND
Alcohol stimulates the release of dopamine in the nucleus accumbens (NACB) of rats, mice and humans. There is evidence to suggest that the activation of beta-endorphin (beta-EP) in the mesolimbic pathway by alcohol and other drugs of abuse may be associated with the rise in dopamine levels in the NACB.
OBJECTIVE
The present studies investigate whether the release of beta-EP in the NACB is (1) dependent on the dose of alcohol that is administered, and (2) associated with changes in the extracellular concentrations of the catecholamines dopamine and norepinephrine, and the dopamine metabolites 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA), in the NACB.
METHODS
Male Sprague-Dawley rats were implanted with a microdialysis probe positioned in the shell region of the NACB. Artificial cerebrospinal fluid was pumped at a rate of 2.3 microl/min in awake and freely moving animals and the dialysate was collected at 30-min intervals. After a baseline period, rats were injected intraperitoneally with either physiological saline or one of three doses of alcohol: 0.8, 1.6, or 2.4 g ethanol/kg body weight. The dialysates collected were analyzed with radioimmunoassay, to estimate the content of beta-EP; and high performance liquid chromatography, to estimate the content of dopamine, norepinephrine, DOPAC and HVA.
RESULTS
Alcohol induced a dose-dependent increase in the extracellular levels of beta-EP and dopamine. However, elevations in the extracellular levels of norepinephrine, DOPAC and HVA did not reach significance. The largest increase in beta-EP and dopamine was observed with the 2.4 g/kg dose.
CONCLUSIONS
The alcohol-induced release of beta-EP and dopamine in the NACB is dose-dependent, where the highest dose resulted in more pronounced concentrations in the dialysate. Furthermore, the increase in the extracellular levels of dopamine appeared to occur at an earlier time point following alcohol administration, than for beta-EP. These results suggest that alcohol stimulates dopamine and beta-EP in the NACB, but probably does so via independent mechanisms.
Publication
Journal: Journal of Leukocyte Biology
June/25/2003
Abstract
We have reported previously that PGE(2) inhibits dendritic cells (DC) functions. Because E prostanoid receptor (EPR) subtypes involved in this action are unknown, expression and functions of these receptors were examined in DC. Western blot and flow cytometry analyses showed that all EPRs were coexpressed in DC. In a dose-dependent manner, lipopolysaccharide (LPS) enhanced EP(2)R/EP(4)R but not EP(1)R/EP(3)R expressions. NS-398, a cyclooxygenase (COX)-2-selective inhibitor, suppressed LPS-enhanced EP(2)R/EP(4)R expression, suggesting that COX-2-issued prostaglandin E(2) (PGE(2)) modulates DC function through stimulation of specific EPR subtypes. Using selective agonists, we found that butaprost, an EP(2)R agonist, and PGE(1) alcohol, an EP(2)R and EP(2)R/EP(4)R agonist, inhibited major histocompatibility complex class II expression and enhanced interleukin-10 production from DC. However, no effect was observed with sulprostone and 17-phenyl-omega-trinor-PGE(2), selective agonists for EP(1)R and EP(1)R/EP(3)R, respectively. Treatment of DC with dibutyryl cyclic adenosine monophosphate (cAMP), an analog of cAMP, mimics PGE(2)-induced, inhibitory effects. Taken together, our data demonstrate that EP(2)R/EP(4)R are efficient for mediating PGE(2)-induced modulation of DC functions.
Publication
Journal: Hepatology
January/22/2007
Abstract
Hepatic progenitor/oval cells appear in injured livers when hepatocyte proliferation is impaired. These cells can differentiate into hepatocytes and cholangiocytes and could be useful for cell and gene therapy applications. In this work, we studied progenitor/oval cell surface markers in the liver of rats subjected to 2-acetylaminofluorene treatment followed by partial hepatectomy (2-AAF/PH) by using rat genome 230 2.0 Array chips and subsequent RT-PCR, immunofluorescent (IF), immunohistochemical (IHC) and in situ hybridization (ISH) analyses. We also studied expression of the identified novel cell surface markers in fetal rat liver progenitor cells and FAO-1 hepatoma cells. Novel cell surface markers in adult progenitor cells included tight junction proteins, integrins, cadherins, cell adhesion molecules, receptors, membrane channels and other transmembrane proteins. From the panel of 21 cell surface markers, 9 were overexpressed in fetal progenitor cells, 6 in FAO-1 cells and 6 are unique for the adult progenitors (CD133, claudin-7, cadherin 22, mucin-1, ros-1, Gabrp). The specificity of progenitor/oval cell surface markers was confirmed by ISH and double IF analyses. Moreover, study of progenitor cells purified with Ep-CAM antibodies from D-galactosamine injured rat liver, a noncarcinogenic model of progenitor cell activation, verified that progenitor cells expressed these markers.
CONCLUSIONS
We identified novel cell surface markers specific for hepatic progenitor/oval cells, which offers powerful tool for their identification, isolation and studies of their physiology and pathophysiology. Our studies also reveal the mesenchymal/epithelial phenotype of these cells and the existence of species diversity in the hepatic progenitor cell identity.
Publication
Journal: Journal of Urology
September/25/2003
Abstract
OBJECTIVE
Chronic prostatitis has been traditionally characterized by inflammation and/or infection of the prostate gland, objectively categorized by white blood cells and cultured bacteria in prostate specific specimens. We compared leukocyte counts and localization rates for bacterial cultures of segmented urine samples (VB1, VB2, VB3), expressed prostatic secretion (EPS) and semen in men diagnosed with chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) to men without pelvic pain (controls).
METHODS
A total of 463 men enrolled in the National Institutes of Health Chronic Prostatitis Cohort study and 121 age matched men without urinary symptoms had leukocyte counts performed and 5-day bacterial cultures on specimens obtained from a standard 4-glass test (VB1, VB2, EPS, VB3) and semen. All risk factor comparisons between case and control analyses were tested using generalized Mantel-Haenszel methods, and multivariable models were developed using logistic regression methods, adjusting for clustering by clinical center within both methods.
RESULTS
Men with CP/CPPS had statistically higher leukocyte counts in all segmented urine samples and EPS, but not in semen compared to asymptomatic control men. However, the control population also had a high prevalence of leukocytes. Of the men with CP/CPPS 50% and 32% had 5 or more, or 10 or more white blood cells (WBCs) per high power field, respectively, in EPS compared to 40% and 20% of the control population. Similarly, 32% and 14% of the patients with CP/CPPS had 5 or more, or 10 or more WBCs per high power field in VB3 compared to 19% and 11% in the control population. Localization of uropathogenic bacteria in EPS, VB3 and/or semen was similar in men with CP/CPPS (8.0%) and asymptomatic men (8.3%).
CONCLUSIONS
Men with CP/CPPS have significantly higher leukocyte counts in all segmented urine samples and EPS but not in semen as compared to controls. There is no difference in rates of localization of bacterial cultures for men with CP/CPPS compared to control men. The high prevalence of WBCs and positive bacterial cultures in the asymptomatic control population raises questions about the clinical usefulness of the standard 4-glass test as a diagnostic tool in men with CP/CPPS.
Publication
Journal: Immunobiology
March/7/2011
Abstract
OBJECTIVE
High mobility group box chromosomal protein 1 (HMGB1) is a lately discovered candidate molecule identified as an important extracellular mediator in systemic inflammation. Systemic inflammation results in endothelial cell activation and microvascular injury. In the present study, we investigated the effects of HMGB1 on the activation of human umbilical vein endothelial cells (HUVECs) and defined pathways activated by HMGB1.
METHODS
HUVECs obtained by collagenase treatment of umbilical cord veins were stimulated in vitro with HMGB1. The activation of HUVECs was studied regarding (i) the kinetics of tumor necrosis factor-α (TNF-α) production in HUVECs, (ii) HMGB1-induced up-regulation of receptor for advanced glycation end products (RAGE), (iii) HMGB1-induced nuclear translocation of nuclear factor kappa B (NF-κB) in HUVECs, (iv) the activation of signalling transduction pathways.
RESULTS
HUVECs activation was stimulated by HMGB1 partially in a RAGE-dependent manner. Additionally, the HMGB1-induced activation of HUVECs was significantly inhibited by anti-RAGE monoclonal antibody and Ethyl pyruvate (EP) that had been shown to be an effective anti-inflammatory agent. Short-term prestimulation of HUVECs with HMGB1 caused a time-dependent increase in the secretion of TNF-α and expression of RAGE. Furthermore, HMGB1 stimulation resulted in nuclear translocation of transcription factor NF-κB. Most importantly, pretreatment with anti-RAGE monoclonal antibody significantly decreased the amounts of TNF-α and inhibited the nuclear translocation of NF-κB. Additionally in HUVECs cultures, EP specifically inhibited activation of NF-κB signaling pathway that are critical for TNF-α release.
CONCLUSIONS
In conclusion, Our data present a link between HMGB1and RAGE function of endothelial cells and demonstrate the pathway activated by HMGB1. These findings may provide a novel therapeutic strategy to improve the endothelial cells function.
Publication
Journal: Journal of Microbiological Methods
August/27/2002
Abstract
Fluorescently labelled lectins were used in combination with epifluorescence microscopy and confocal laser scanning microscopy to allow the visualization and characterization of carbohydrate-containing extracellular polymeric substances (EPS) in biofilms of Pseudomonas aeruginosa. A mucoid strain characterized by an overproduction of the exopolysaccharide alginate, and an isogenic, non-mucoid strain were used. Model biofilms grown on polycarbonate filters were treated with lectins concanavalin A (ConA) and wheat germ agglutinin (WGA) that were fluorescently labelled with fluorescein isothiocyanate or tetramethyl rhodamine isothiocyanate. Fluorescently labelled ConA yielded cloud-like regions that were heterogeneously distributed within mucoid biofilms, whereas these structures were only rarely present in biofilms of the non-mucoid strain. The bacteria visualized with the fluorochrome SYTO 9 were localized both within and between the ConA-stained regions. In WGA-treated biofilms, the lectin was predominantly associated with bacterial cells. Alginate seemed to be involved in the interaction of ConA with the EPS matrix, since (i) pre-treatment of biofilms with an alginate lyase resulted in a loss of ConA biofilm staining, and (ii) using an enzyme-linked lectinsorbent assay (ELLA), ConA was shown to bind to purified alginate, but not to alginate that was degraded by alginate lyase. The application of fluorescently labelled lectins in combination with ELLA was found to be useful for the visualization and characterization of extracellular polysaccharide structures in P. aeruginosa biofilms.
Publication
Journal: Journal of Proteome Research
February/25/2013
Abstract
Biofilms are surface-associated bacteria that are embedded in a matrix of self-produced polymeric substances (EPSs). The EPS is composed of nucleic acids, polysaccharides, lipids, and proteins. While polysaccharide components have been well studied, the protein content of the matrix is largely unknown. Here we conducted a comprehensive proteomic study to identify proteins associated with the biofilm matrix of Pseudomonas aeruginosa PAO1 (the matrix proteome). This analysis revealed that approximately 30% of the identified matrix proteins were outer membrane proteins, which are also typically found in outer membrane vesicles (OMVs). Electron microscopic inspection confirmed the presence of large amounts of OMVs within the biofilm matrix, supporting previous notions that OMVs are abundant constituents of P. aeruginosa biofilms. Our results demonstrate that while some proteins associated with the P. aeruginosa matrix are derived from secreted proteins and lysed cells, the large majority of the matrix proteins originate from OMVs. Furthermore, we demonstrate that the protein content of planktonic and biofilm OMVs is surprisingly different and may reflect the different physiological states of planktonic and sessile cells.
Publication
Journal: Journal of the American College of Cardiology
September/20/2006
Abstract
OBJECTIVE
The purpose of this study was to determine quality of life (QOL) and exercise performance (EP) in patients with persistent atrial fibrillation (AF) converted to sinus rhythm (SR) compared with those remaining in or reverting to AF.
BACKGROUND
Restoration of SR in patients with AF improving QOL and EP remains controversial.
METHODS
Patients with persistent AF were randomized double-blind to amiodarone, sotalol, or placebo. Those not achieving SR at day 28 were cardioverted and classified into SR or AF groups at 8 weeks (n = 624) and 1 year (n = 556). The QOL (SF-36), symptom checklist (SCL), specific activity scale (SAS), AF severity scale (AFSS), and EP were assessed.
RESULTS
Favorable changes were seen in SR patients at 8 weeks in physical functioning (p < 0.001), physical role limitations (p = 0.03), general health (p = 0.002), and vitality (p < 0.001), and at 1 year in general health (p = 0.007) and social functioning (p = 0.02). Changes in the scores for SCL severity (p = 0.01), functional capacity (p = 0.003), and AFSS symptom burden (p < 0.001) at 8 weeks and in SCL severity (p < 0.01) and AF symptom burden (p < 0.001) at 1 year showed significant improvements in SR versus AF. Symptomatic patients were more likely to have improvement. The EP in SR versus AF was greater from baseline to 8 weeks (p = 0.01) and to 1 year (p = 0.02). The EP correlated with physical functioning and functional capacity except in the AF group at 1 year.
CONCLUSIONS
In patients with persistent AF, restoration and maintenance of SR was associated with improvements in QOL measures and EP. There was a strong correlation between QOL measures and EP.
Publication
Journal: Environmental Microbiology
September/12/2005
Abstract
Concepts from previous biofilm models were integrated to create a framework for the implementation of multidimensional (2D and 3D) multispecies biofilm models. The framework is here described at three levels: (i) mathematical representation of the processes involved in biofilm formation, (ii) numerical implementation into a computer program (freely available from our website http://www.biofilms.bt.tudelft.nl/frameworkMaterial) and (iii) using the program for the creation of biofilm models with multiple bacterial and solute species. An improved version of the individual-based modelling (IbM) that allows structured biomass was used. In this approach biomass composition may be discriminated into any number of particulate species, including extracellular polymeric substances (EPS) for which specific functionality was included. Detachment is also included, described as occurring at the biofilm surface with variable local rates derived from functions of state variables. The application of this modelling framework to a multispecies system with structured biomass is illustrated in a case study where the competition between an organism capable of accumulating polyhydroxybutyrate (PHB, an internal storage compound) and an EPS-producing organism in a two-species biofilm is analysed. Results illustrate that biofilms enriched in PHB-producing organisms may be obtained by supplying substrate intermittently in feast/famine cycles.
Publication
Journal: International Journal of Neuropsychopharmacology
January/14/2014
Abstract
Because early treatment choice is critical in first-episode schizophrenia-spectrum disorders (FES), this meta-analysis compared efficacy and tolerability of individual second-generation antipsychotics (SGAs) with first-generation antipsychotics (FGAs) in FES. We conducted systematic literature search (until 12 December 2010) and meta-analysis of acute, randomized trials with ≥1 FGA vs. SGA comparison; patients in their first episode of psychosis and diagnosed with schizophrenia-spectrum disorders; available data for psychopathology change, treatment response, treatment discontinuation, adverse effects, or cognition. Across 13 trials (n = 2509), olanzapine (seven trials) and amisulpride (one trial) outperformed FGAs (haloperidol: 9/13 trials) in 9/13 and 8/13 efficacy outcomes, respectively, risperidone (eight trials) in 4/13, quetiapine (one trial) in 3/13 and clozapine (two trials) and ziprasidone (one trial) in 1/13, each. Compared to FGAs, extrapyramidal symptom (EPS)-related outcomes were less frequent with olanzapine, risperidone and clozapine, but weight gain was greater with clozapine, olanzapine and risperidone. Pooled SGAs were similar to FGAs regarding total psychopathology change, depression, treatment response and metabolic changes. SGAs significantly outperformed FGAs regarding lower treatment discontinuation, irrespective of cause, negative symptoms, global cognition and less EPS and akathisia, while SGAs increased weight more (p < 0.05-0.01). Results were not affected by FGA dose or publication bias, but industry-sponsored studies favoured SGAs more than federally funded studies. To summarize, in FES, olanzapine, amisulpride and, less so, risperidone and quetiapine showed superior efficacy, greater treatment persistence and less EPS than FGAs. However, weight increase with olanzapine, risperidone and clozapine and metabolic changes with olanzapine were greater. Additional FES studies including broader-based SGAs and FGAs are needed.
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