bluuebunny/crossref_metadata_2025 huggingface dataset:
Enforced expression of miR-125b affects myelopoiesis by targeting multiple signaling pathways
Authors: Surdziel Ewa , Cabanski Maciej , Dallmann Iris , Lyszkiewicz Marcin , Krueger Andreas , Ganser Arnold , Scherr Michaela , Eder Matthias
Published: March 2011

MicroRNAs (miRNAs) are small, noncoding RNAs that regulate gene expression by sequence-specific targeting of multiple mRNAs. Although lineage-, maturation-, and disease-specific miRNA expression has been described, miRNA-dependent phenotypes and miRNA-regulated signaling in hematopoietic cells are largely unknown. Combining functional genomics, biochemical analysis, and unbiased and hypothesis-driven miRNA target prediction, we show that lentivirally over-expressed miR-125b blocks G-CSF–induced granulocytic differentiation and enables G-CSF–dependent proliferation of murine 32D cells. In primary lineage-negative cells, miR-125b over-expression enhances colony-formation in vitro and promotes myelopoiesis in mouse bone marrow chimeras. We identified Stat3 and confirmed Bak1 as miR-125b target genes with approximately 30% and 50% reduction in protein expression, respectively. However, gene-specific RNAi reveals that this reduction, alone and in combination, is not sufficient to block G-CSF–dependent differentiation. STAT3 protein expression, DNA-binding, and transcriptional activity but not induction of tyrosine-phosphorylation and nuclear translocation are reduced upon enforced miR-125b expression, indicating miR-125b–mediated reduction of one or more STAT3 cofactors. Indeed, we identified c-Jun and Jund as potential miR-125b targets and demonstrated reduced protein expression in 32D/miR-125b cells. Interestingly, gene-specific silencing of JUND but not c-JUN partially mimics the miR-125b over-expression phenotype. These data demonstrate coordinated regulation of several signaling pathways by miR-125b linked to distinct phenotypes in myeloid cells.
HIV-1–related Hodgkin lymphoma in the era of combination antiretroviral therapy: incidence and evolution of CD4+ T-cell lymphocytes
Authors: Bohlius Julia , Schmidlin Kurt , Boué François , Fätkenheuer Gerd , May Margaret , Caro-Murillo Ana Maria , Mocroft Amanda , Bonnet Fabrice , Clifford Gary , Paparizos Vassilios , Miro Jose M. , Obel Niels , Prins Maria , Chêne Geneviève , Egger Matthias ,   Collaboration of Observational HIV Epidemiological Research Europe
Published: March 2011

The risk of Hodgkin lymphoma (HL) is increased in patients infected with HIV-1. We studied the incidence and outcomes of HL, and compared CD4+ T-cell trajectories in HL patients and controls matched for duration of combination antiretroviral therapy (cART). A total of 40 168 adult HIV-1–infected patients (median age, 36 years; 70% male; median CD4 cell count, 234 cells/μL) from 16 European cohorts were observed during 159 133 person-years; 78 patients developed HL. The incidence was 49.0 (95% confidence interval [CI], 39.3-61.2) per 100 000 person-years, and similar on cART and not on cART (P = .96). The risk of HL declined as the most recent (time-updated) CD4 count increased: the adjusted hazard ratio comparing more than 350 with less than 50 cells/μL was 0.27 (95% CI, 0.08-0.86). Sixty-one HL cases diagnosed on cART were matched to 1652 controls: during the year before diagnosis, cases lost 98 CD4 cells (95% CI, −159 to −36 cells), whereas controls gained 35 cells (95% CI, 24-46 cells; P < .0001). The incidence of HL is not reduced by cART, and patients whose CD4 cell counts decline despite suppression of HIV-1 replication on cART may harbor HL.
Heparin promotes platelet responsiveness by potentiating αIIbβ3-mediated outside-in signaling
Authors: Gao Cunji , Boylan Brian , Fang Juan , Wilcox David A. , Newman Debra K. , Newman Peter J.
Published: March 2011

Unfractionated heparin (UFH) is a widely used anticoagulant that has long been known to potentiate platelet responses to subthreshold doses of platelet agonists. UFH has been reported to bind and induce modest conformational changes in the major platelet integrin, αIIbβ3, and induce minor changes in platelet morphology. The mechanism by which UFH elicits these platelet-activating effects, however, is not well understood. We found that both human and murine platelets exposed to UFH, either in solution or immobilized onto artificial surfaces, underwent biochemical and morphologic changes indicative of a potentiated state, including phosphorylation of key cytosolic signaling molecules and cytoskeletal changes leading to cell spreading. Low molecular weight heparin and the synthetic pentasaccharide, fondaparinux, had similar platelet-potentiating effects. Human or mouse platelets lacking functional integrin αIIbβ3 complexes and human platelets pretreated with the fibrinogen receptor antagonists eptifibatide or abciximab failed to become potentiated by heparin, demonstrating that heparin promotes platelet responsiveness via its ability to initiate αIIbβ3-mediated outside-in signaling. Taken together, these data provide novel insights into the mechanism by which platelets become activated after exposure to heparin and heparin-coated surfaces, and suggest that currently used glycoprotein IIb-IIIa inhibitors may be effective inhibitors of nonimmune forms of heparin-induced platelet activation.
Inhibition of mTOR blocks the anti-inflammatory effects of glucocorticoids in myeloid immune cells
Authors: Weichhart Thomas , Haidinger Michael , Katholnig Karl , Kopecky Chantal , Poglitsch Marko , Lassnig Caroline , Rosner Margit , Zlabinger Gerhard J. , Hengstschläger Markus , Müller Mathias , Hörl Walter H. , Säemann Marcus D.
Published: March 2011

A central role for the mammalian target of rapamycin (mTOR) in innate immunity has been recently defined by its ability to limit proinflammatory mediators. Although glucocorticoids (GCs) exert potent anti-inflammatory effects in innate immune cells, it is currently unknown whether the mTOR pathway interferes with GC signaling. Here we show that inhibition of mTOR with rapamycin or Torin1 prevented the anti-inflammatory potency of GC both in human monocytes and myeloid dendritic cells. GCs could not suppress nuclear factor-κB and JNK activation, the expression of proinflammatory cytokines, and the promotion of Th1 responses when mTOR was inhibited. Interestingly, long-term activation of monocytes with lipopolysaccharide enhanced the expression of TSC2, the principle negative regulator of mTOR, whereas dexamethasone blocked TSC2 expression and reestablished mTOR activation. Renal transplant patients receiving rapamycin but not those receiving calcineurin inhibitors displayed a state of innate immune cell hyper-responsiveness despite the concurrent use of GC. Finally, mTOR inhibition was able to override the healing phenotype of dexamethasone in a murine lipopolysaccharide shock model. Collectively, these data identify a novel link between the glucocorticoid receptor and mTOR in innate immune cells, which is of considerable clinical importance in a variety of disorders, including allogeneic transplantation, autoimmune diseases, and cancer.
Accumulation and transport of microbial-size particles in a pressure protected model burn unit: CFD simulations and experimental evidence
Authors: Beauchêne Christian , Laudinet Nicolas , Choukri Firas , Rousset Jean-Luc , Benhamadouche Sofiane , Larbre Juliette , Chaouat Marc , Benbunan Marc , Mimoun Maurice , Lajonchère Jean-Patrick , Bergeron Vance , Derouin Francis
Published: March 2011

Background

Controlling airborne contamination is of major importance in burn units because of the high susceptibility of burned patients to infections and the unique environmental conditions that can accentuate the infection risk. In particular the required elevated temperatures in the patient room can create thermal convection flows which can transport airborne contaminates throughout the unit. In order to estimate this risk and optimize the design of an intensive care room intended to host severely burned patients, we have relied on a computational fluid dynamic methodology (CFD).

Methods

The study was carried out in 4 steps: i) patient room design, ii) CFD simulations of patient room design to model air flows throughout the patient room, adjacent anterooms and the corridor, iii) construction of a prototype room and subsequent experimental studies to characterize its performance iv) qualitative comparison of the tendencies between CFD prediction and experimental results. The Electricité De France (EDF) open-source software Code_Saturne
® (http://www.code-saturne.org) was used and CFD simulations were conducted with an hexahedral mesh containing about 300 000 computational cells. The computational domain included the treatment room and two anterooms including equipment, staff and patient. Experiments with inert aerosol particles followed by time-resolved particle counting were conducted in the prototype room for comparison with the CFD observations.

Results

We found that thermal convection can create contaminated zones near the ceiling of the room, which can subsequently lead to contaminate transfer in adjacent rooms. Experimental confirmation of these phenomena agreed well with CFD predictions and showed that particles greater than one micron (i.e. bacterial or fungal spore sizes) can be influenced by these thermally induced flows. When the temperature difference between rooms was 7°C, a significant contamination transfer was observed to enter into the positive pressure room when the access door was opened, while 2°C had little effect. Based on these findings the constructed burn unit was outfitted with supplemental air exhaust ducts over the doors to compensate for the thermal convective flows.

Conclusions

CFD simulations proved to be a particularly useful tool for the design and optimization of a burn unit treatment room. Our results, which have been confirmed qualitatively by experimental investigation, stressed that airborne transfer of microbial size particles via thermal convection flows are able to bypass the protective overpressure in the patient room, which can represent a potential risk of cross contamination between rooms in protected environments.
Structural analysis of heme proteins: implications for design and prediction
Authors: Li Ting , Bonkovsky Herbert L , Guo Jun-tao
Published: March 2011

Background

Heme is an essential molecule and plays vital roles in many biological processes. The structural determination of a large number of heme proteins has made it possible to study the detailed chemical and structural properties of heme binding environment. Knowledge of these characteristics can provide valuable guidelines in the design of novel heme proteins and help us predict unknown heme binding proteins.

Results

In this paper, we constructed a non-redundant dataset of 125 heme-binding protein chains and found that these heme proteins encompass at least 31 different structural folds with all-α class as the dominating scaffold. Heme binding pockets are enriched in aromatic and non-polar amino acids with fewer charged residues. The differences between apo and holo forms of heme proteins in terms of the structure and the binding pockets have been investigated. In most cases the proteins undergo small conformational changes upon heme binding. We also examined the CP (cysteine-proline) heme regulatory motifs and demonstrated that the conserved dipeptide has structural implications in protein-heme interactions.

Conclusions

Our analysis revealed that heme binding pockets show special features and that most of the heme proteins undergo small conformational changes after heme binding, suggesting the apo structures can be used for structure-based heme protein prediction and as scaffolds for future heme protein design.
Time-course of sFlt-1 and VEGF-A release in neutropenic patients with sepsis and septic shock: a prospective study
Authors: Alves Brunna E , Montalvao Silmara AL , Aranha Francisco JP , Lorand-Metze Irene , De Souza Carmino A , Annichino-Bizzacchi Joyce M , De Paula Erich V
Published: March 2011

Background

Septic shock is the most feared complication of chemotherapy-induced febrile neutropenia. So far, there are no robust biomarkers that can stratify patients to the risk of sepsis complications. The VEGF-A axis is involved in the control of microvascular permeability and has been involved in the pathogenesis of conditions associated with endothelial barrier disruption such as sepsis. sFlt-1 is a soluble variant of the VEGF-A receptor VEGFR-1 that acts as a decoy receptor down-regulating the effects of VEGF-A. In animal models of sepsis, sFlt-1 was capable to block the barrier-breaking negative effects of VEGF-A and to significantly decrease mortality. In non-neutropenic patients, sFlt-1 has been shown to be a promising biomarker for sepsis severity.

Methods

We prospectively evaluated concentrations of sFlt-1 and VEGF-A at different time-points during febrile neutropenia, and evaluated the association of these levels with sepsis severity and septic shock development.

Results

Neutropenic patients that evolved with septic shock (n = 10) presented higher levels of sFlt-1 and VEGF-A measured 48 hours after fever onset than patients with non-complicated sepsis (n = 31) and levels of these biomarkers correlated with sepsis severity scores. Estimation of the diagnostic accuracy of sFlt-1 levels for the discrimination of patients that evolved to septic shock yielded promising results in our study population.

Discussion

Our data suggest that sFlt-1 and VEGF-A could be useful biomarkers for sepsis severity in patients with febrile neutropenia. In addition, the kinetics of sFlt-1 release in patients that evolve to septic shock suggest that the sFlt-1 could be a salvage compensatory mechanism in patients with septic shock, but that the magnitude of the sFlt-1 release observed in human sepsis is not sufficient to reproduce the beneficial anti-VEGF-A effects observed in animal models of sepsis.
Chemical characterization of extra layers at the interfaces in MOCVD InGaP/GaAs junctions by electron beam methods
Authors: Frigeri Cesare , Shakhmin Alexey Aleksandrovich , Vinokurov Dmitry Anatolievich , Zamoryanskaya Maria Vladimirovna
Published: March 2011

Electron beam methods, such as cathodoluminescence (CL) that is based on an electron-probe microanalyser, and (200) dark field and high angle annular dark field (HAADF) in a scanning transmission electron microscope, are used to study the deterioration of interfaces in InGaP/GaAs system with the GaAs QW on top of InGaP. A CL emission peak different from that of the QW was detected. By using HAADF, it is found that the GaAs QW does not exist any longer, being replaced by extra interlayer(s) that are different from GaAs and InGaP because of atomic rearrangements at the interface. The nature and composition of the interlayer(s) are determined by HAADF. Such changes of the nominal GaAs QW can account for the emission observed by CL.
Insulin-like growth factor-I gene delivery to astrocytes reduces their inflammatory response to lipopolysaccharide
Authors: Bellini Maria J , Hereñú Claudia B , Goya Rodolfo G , Garcia-Segura Luis M
Published: March 2011

Background

Insulin-like growth factor-I (IGF-I) exerts neuroprotective actions in the central nervous system that are mediated at least in part by control of activation of astrocytes. In this study we have assessed the efficacy of exogenous IGF-I and IGF-I gene therapy in reducing the inflammatory response of astrocytes from cerebral cortex.

Methods

An adenoviral vector harboring the rat IGF-I gene and a control adenoviral vector harboring a hybrid gene encoding the herpes simplex virus type 1 thymidine kinase fused toAequorea victoriaenhanced green fluorescent protein were used in this study. Primary astrocytes from mice cerebral cortex were incubated for 24 h or 72 h with vehicle, IGF-I, the IGF-I adenoviral vector, or control vector; and exposed to bacterial lipopolysaccharide to induce an inflammatory response. IGF-I levels were measured by radioimmunoassay. Levels of interleukin 6, tumor necrosis factor-α, interleukin-1β and toll-like receptor 4 mRNA were assessed by quantitative real-time polymerase chain reaction. Levels of IGF-I receptor and IGF binding proteins 2 and 3 were assessed by western blotting. The subcellular distribution of nuclear factor κB (p65) was assessed by immunocytochemistry. Statistical significance was assessed by one way analysis of variance followed by the Bonferroni pot hoc test.

Results

IGF-I gene therapy increased IGF-I levels without affecting IGF-I receptors or IGF binding proteins. Exogenous IGF-I, and IGF-I gene therapy, decreased expression of toll-like receptor 4 and counteracted the lipopolysaccharide-induced inflammatory response of astrocytes. In addition, IGF-I gene therapy decreased lipopolysaccharide-induced translocation of nuclear factor κB (p65) to the cell nucleus.

Conclusion

These findings demonstrate efficacy of exogenous IGF-I and of IGF-I gene therapy in reducing the inflammatory response of astrocytes. IGF-I gene therapy may represent a new approach to reduce inflammatory reactions in glial cells.
Newly recognized mosquito-associated viruses in mainland China, in the last two decades
Authors: Liu Hong , Gao Xiaoyan , Liang Guodong
Published: March 2011

There are four principal arboviruses in mainland China. Two kinds of them are mosquito-borne viruses, namely Japanese encephalitis virus and dengue virus, which lead to Japanese encephalitis, and dengue fever/dengue hemorrhagic fever respectively; the other two are tick-borne viruses, namely tick-borne encephalitis virus and Crimean-Congo hemorrhagic fever virus (also known as Xinjiang hemorrhagic fever virus), which contribute to tick-borne encephalitis and Xinjiang hemorrhagic fever respectively. With exception of these four main arboviruses, many other mosquito-associated viruses have been isolated and identified in recent years. These newly isolated and identified mosquito-associated viruses are probably responsible for human and animal infections and diseases. The purpose of this review is to describe the newly isolated mosquito-associated viruses in mainland China which belong to five viral families, including their virological properties, phylogenetic relationships, serological evidence, as well as to appeal the public health concentration worldwide.
Intravaginal cytomegalovirus (CMV) challenge elicits maternal viremia and results in congenital transmission in a guinea pig model
Authors: Olejniczak Megan J , Choi K Yeon , McVoy Michael A , Cui Xiaohong , Schleiss Mark R
Published: March 2011

Background

The objective of this study was to compare intravaginal (ivg) and subcutaneous (sc) administration of the guinea pig cytomegalovirus (GPCMV) in pregnant and non-pregnant guinea pigs. These studies tested the hypotheses that ivg infection would elicit immune responses, produce maternal viremia, and lead to vertical transmission, with an efficiency similar to the traditionally employed sc route.

Results

Four groups of age- and size-matched guinea pigs were studied. Two groups were pregnant, and two groups were not pregnant. Animals received 5x105 plaque-forming units (PFU) of a GPCMV reconstituted from an infectious bacterial artificial chromosome (BAC) construct containing the full-length GPCMV genome. Seroconversion was compared by IgG ELISA, and viremia (DNAemia) was monitored by PCR. In both pregnant and non-pregnant animals, sc inoculation resulted in significantly higher serum ELISA titers than ivg inoculation at 8 and 12 weeks post-infection. Patterns of viremia (DNAemia) were similar in animals inoculated by either sc or ivg route. However, in pregnant guinea pigs, animals inoculated by both routes experienced an earlier onset of DNAemia than did non-pregnant animals. Neither the percentage of dead pups nor the percentage of GPCMV positive placentas differed by inoculation route.

Conclusions

In the guinea pig model of congenital CMV infection, the ivg route is as efficient at causing congenital infection as the conventional but non-physiologic sc route. This finding could facilitate future experimental evaluation of vaccines and antiviral interventions in this highly relevant animal model.
Occult HBV infection among Egyptian hepatocellular carcinoma patients
Authors: Hassan Zeinab K , Hafez Mohamed M , Mansor Tarek M , Zekri Abdel N Rahman
Published: March 2011

Background

Occult HBV infection accelerates the progression of liver fibrosis, cirrhosis, and finally leading to hepatocellular carcinoma (HCC). This study analyzed the occult HBV-genotypes in HCC patients.

Methods

To achieve our objective, matched serum and tissue samples were collected from 40 HCC patients. Three sets of primers were used for the HBV-DNA detection by nested-PCR, which cover the HBV-genome; Core, Surface and X genes. Genotyping system based on PCR using type-specific primers was applied on HBV-DNA positive samples.

Results

Intrahepatic occult HBV-DNA was detected in 62.5%, whereas; Serum occult HBV-DNA were detected in only 22.5% of HCC patients. In patients' positive for both anti-HBs and anti-HBc, 10% had occult HBV in serum. In serologically negative HCV patients, 63% had intrahepatic HBV-DNA, and 21% had HBV-DNA in serum samples. HBV-genotype D (32%) and B (24%) attributed predominantly to intrahepatic HBV infections in HCC patients, whereas HBV-genotype A (4%) and C (8%) infections were the least observed.

Conclusion

This is the first study to show the genotypes of occult HBV infection in HCC Patients. We suggest that B or D may influence the outcome of HBV infection which may lead to the development of HCC.
Cytotoxicity and oxidative stress induced by different metallic nanoparticles on human kidney cells
Authors: Pujalté Igor , Passagne Isabelle , Brouillaud Brigitte , Tréguer Mona , Durand Etienne , Ohayon-Courtès Céline , L'Azou Béatrice
Published: March 2011

Background

Some manufactured nanoparticles are metal-based and have a wide variety of applications in electronic, engineering and medicine. Until now, many studies have described the potential toxicity of NPs on pulmonary target, while little attention has been paid to kidney which is considered to be a secondary target organ. The objective of this study, on human renal culture cells, was to assess the toxicity profile of metallic nanoparticles (TiO2, ZnO and CdS) usable in industrial production. Comparative studies were conducted, to identify whether particle properties impact cytotoxicity by altering the intracellular oxidative status.

Results

Nanoparticles were first characterized by size, surface charge, dispersion and solubility. Cytotoxicity of NPs was then evaluated in IP15 (glomerular mesangial) and HK-2 (epithelial proximal) cell lines. ZnO and CdS NPs significantly increased the cell mortality, in a dose-dependent manner. Cytotoxic effects were correlated with the physicochemical properties of NPs tested and the cell type used. Analysis of reactive oxygen species and intracellular levels of reduced and oxidized glutathione revealed that particles induced stress according to their composition, size and solubility. Protein involved in oxidative stress such as NF-κb was activated with ZnO and CdS nanoparticles. Such effects were not observed with TiO2 nanoparticles.

Conclusion

On glomerular and tubular human renal cells, ZnO and CdS nanoparticles exerted cytotoxic effects that were correlated with metal composition, particle scale and metal solubility. ROS production and oxidative stress induction clearly indicated their nephrotoxic potential.
Reliable transgene-independent method for determining Sleeping Beauty transposon copy numbers
Authors: Kolacsek Orsolya , Krízsik Virág , Schamberger Anita , Erdei Zsuzsa , Apáti Ágota , Várady György , Mátés Lajos , Izsvák Zsuzsanna , Ivics Zoltán , Sarkadi Balázs , Orbán Tamás I
Published: March 2011

Background

The transposon-based gene delivery technique is emerging as a method of choice for gene therapy. The Sleeping Beauty (SB) system has become one of the most favored methods, because of its efficiency and its random integration profile. Copy-number determination of the delivered transgene is a crucial task, but a universal method for measuring this is lacking. In this paper, we show that a real-time quantitative PCR-based, transgene-independent (qPCR-TI) method is able to determine SB transposon copy numbers regardless of the genetic cargo.

Results

We designed a specific PCR assay to amplify the left inverted repeat-direct repeat region of SB, and used it together with the single-copy control gene RPPH1 and a reference genomic DNA of known copy number. The qPCR-TI method allowed rapid and accurate determination of SB transposon copy numbers in various cell types, including human embryonic stem cells. We also found that this sensitive, rapid, highly reproducible and non-radioactive method is just as accurate and reliable as the widely used blotting techniques or the transposon display method. Because the assay is specific for the inverted repeat region of the transposon, it could be used in any system where the SB transposon is the genetic vehicle.

Conclusions

We have developed a transgene-independent method to determine copy numbers of transgenes delivered by the SB transposon system. The technique is based on a quantitative real-time PCR detection method, offering a sensitive, non-radioactive, rapid and accurate approach, which has a potential to be used for gene therapy.
New horizons in Biophysics
Authors: Moylan Elizabeth C
Published: March 2011

This editorial celebrates the re-launch of PMC Biophysics previously published by PhysMath Central, in its new format as BMC Biophysics published by BioMed Central with an expanded scope and Editorial Board. BMC Biophysics will fill its own niche in the BMC series alongside complementary companion journals including BMC Bioinformatics, BMC Medical Physics, BMC Structural Biology and BMC Systems Biology.
Diffusion and association processes in biological systems: theory, computation and experiment
Authors: Mereghetti Paolo , Kokh Daria , McCammon J Andrew , Wade Rebecca C
Published: March 2011

Macromolecular diffusion plays a fundamental role in biological processes. Here, we give an overview of recent methodological advances and some of the challenges for understanding how molecular diffusional properties influence biological function that were highlighted at a recent workshop, BDBDB2, the second Biological Diffusion and Brownian Dynamics Brainstorm.
Brownian dynamics simulation of analytical ultracentrifugation experiments
Authors: Díez AI , Ortega A , Garcia de la Tore J
Published: March 2011

Background

We have devised a protocol for the Brownian dynamics simulation of an analytical ultracentrifugation experiment that allows for an accurate and efficient prediction of the time-dependent concentration profiles, c(r, t) in the ultracentrifuge cell. The procedure accounts for the back-diffusion, described as a Brownian motion that superimposes to the centrifugal drift, and considers the sector-shaped geometry of the cell and the boundaries imposed by the meniscus and bottom.

Results

Simulations are carried out for four molecules covering a wide range of the ratio of sedimentation and diffusion coefficients. The evaluation is done by extracting the molecular parameters that were initially employed in the simulation by analyzing the profiles with an independent tool, the well-proved SEDFIT software. The code of simulation algorithm has been parallelized in order to take advantage of current multi-core computers.

Conclusions

Our Brownian dynamics simulation procedure may be considered as an alternative to other predictors based in numerical solutions of the Lamm equation, and its efficiency could make it useful in the most relevant, inverse problem, which is that of extracting the molecular parameters from experimentally determined concentration profiles.
Human β-defensin-2 enhances IFN-γ and IL-10 production and suppresses IL-17 production in T cells
Authors: Kanda Naoko , Kamata Masahiro , Tada Yayoi , Ishikawa Takeko , Sato Shinichi , Watanabe Shinichi
Published: March 2011

Psoriasis is an inflammatory dermatosis with enhanced expression of hBD-2 in keratinocytes and infiltration of cytokine-producing T cells, which in turn, up- or down-regulate hBD-2 expression. We determined the serum levels of hBD-2 and cytokines in psoriasis patients and analyzed the effects of hBD-2 on cytokine production in human peripheral blood T cells. Serum hBD-2 levels in patients were higher than those in controls and correlated with PASI, serum IFN-γ, and IL-10 levels and correlated inversely with serum IL-17 levels. IFN-γ, IL-17, IL-22, TNF-α, IL-1β, and IL-6 enhanced, and IL-10, IL-4, and IL-13 suppressed hBD-2 secretion from keratinocytes. hBD-2 enhanced secretion and mRNA levels of IFN-γ, TNF-α, IL-10, IL-1β, IL-6, and IL-22 and reduced those of IL-17 in CD3/28-stimulated T cells. These effects of hBD-2 were counteracted by PTX. hBD-2 induced phosphorylation of JNK, ERK, and Akt in T cells. Inhibitors of these signals attenuated hBD-2-induced production of IFN-γ, TNF-α, IL-10, IL-1β, IL-6, and IL-22. hBD-2 suppressed phosphorylation of STAT3 and enhanced expression of SOCS3 in CD3/28-stimulated T cells. siRNA against SOCS3 reversed hBD-2-induced suppression of IL-17 production and STAT3 phosphorylation. JNK and MEK inhibitors suppressed hBD-2-induced expression of SOCS3. In conclusion, hBD-2 may bind PTX-sensitive GPCR(s) on T cells and act as a stimulator by enhancing IFN-γ, TNF-α, IL-1β, IL-6, and IL-22 production via JNK, MEK/ERK, and PI3K/Akt and as a regulator by suppressing IL-17 production via SOCS3 or by stimulating IL-10 production.
Complementary and contrasting roles of NK cells and T cells in pediatric umbilical cord blood transplantation
Authors: Merindol Natacha , Charrier Emily , Duval Michel , Soudeyns Hugo
Published: March 2011

UCBT has been used for almost 25 years to treat a variety of malignant and nonmalignant childhood diseases. The biological properties of NK cells and T cells and their implication in engraftment, immune reconstitution, OIs, leukemic relapse, and GvHD have been explored in the context of UCBT. These studies have established that lymphocytes have a major impact on the outcome of UCBT and that NK cells and T cells play complementary and contrasting roles in immune reconstitution and the GvL effect. Therefore, novel strategies to improve the outcome of UCBT recipients, including immunotherapeutic regimens, should be based on key immunologic features of UCB T lymphocytes and NK cells.
The CD40/CD40 ligand interactions exert pleiotropic effects on bone marrow granulopoiesis
Authors: Mavroudi Irene , Papadaki Vassiliki , Pyrovolaki Katerina , Katonis Pavlos , Eliopoulos Aristides G , Papadaki Helen A
Published: March 2011

CD40 is a member of the TNFR family and upon interaction with its cognate ligand (CD40L), induces diverse biologic responses related to cell survival/growth. As altered CD40/CD40L interactions have been associated with neutropenia, we investigated the role of CD40/CD40L on human granulopoiesis using immunomagnetically sorted CD34+, CD34–/CD33+, and CD34–/CD33–/CD15+ BM cells, which represent sequential stages of the granulocytic development, the KG-1 cells that constantly express CD34 and CD33, and LTBMCs that mimic the BM microenvironment. CD40 and CD40L were minimally expressed on CD34+, CD34–/CD33+, and CD34–/CD33–/CD15+ cells, but CD40 was substantially induced in the presence of TNF-α. Cross-linking of CD40 in the above cell populations resulted in induction of apoptosis that was enhanced further in the presence of FasL. CD40 activation in primary as wells as in KG-1 cells resulted in Fas up-regulation, providing a mechanism for the CD40-mediated apoptosis. Addition of CD40L in clonogenic assays resulted in a significant decrease in the colony-forming capacity of BMMCs from patients with chronic neutropenia, presumably expressing high levels of CD40 in the progenitor cells, and this effect was reversed upon CD40 blockade. CD40 was constitutively expressed on LTBMC stromal cells and upon activation, resulted in an increase in G-CSF and GM-CSF production. These data show that CD40/CD40L interactions may promote granulopoiesis under steady-state conditions by inducing the stromal release of granulopoiesis-supporting cytokines, whereas under inflammatory conditions, they may affect the granulocytic progenitor/precursor cell survival by accelerating the Fas-mediated apoptosis.
Unreplaced Sex Steroid Deficiency, Corticotropin Deficiency, and Lower IGF-I Are Associated with Lower Bone Mineral Density in Adults with Growth Hormone Deficiency: A KIMS Database Analysis
Authors: Tritos Nicholas A. , Greenspan Susan L. , King Donna , Hamrahian Amir , Cook David M. , Jönsson Peter J. , Wajnrajch Michael P. , Koltowska-Häggstrom Maria , Biller Beverly M. K.
Published: March 2011

Context:

GH deficiency (GHD) is associated with low bone mineral density (BMD). Risk factors for lower BMD in this GHD population have not been fully elucidated. In particular, there are limited published data in GH-naïve subjects.

Objective:

The objective of the study was to identify endocrine correlates of low BMD in treatment-naïve adult GHD subjects.

Design:

This was a retrospective analysis of data extracted from the (Pfizer International Metabolic Study) KIMS database.

Setting:

The study was an international epidemiological survey of more than 15,000 adult GHD patients from 31 countries.

Patients:

A total of 1218 subjects with stringently defined GHD of adult onset (641 women and 577 men) who were GH naïve and had BMD measured in the posterior anterior lumbar spine and femoral neck by dual-energy X-ray absorptiometry.

Main Outcome Measures:

Variables associated with standardized BMD (sBMD) in adult-onset GHD were examined.

Results:

In the LS, body mass index (r = 0.13, P < 0.01), unreplaced sex steroid deficiency (r = −0.17, P < 0.0001), and corticotropin deficiency (r = −0.11, P < 0.01) were independently associated with sBMD. In the FN, age (r = −0.19, P < 0.0001), female gender (r = −0.18, P < 0.0001), body mass index (r = 0.21, P < 0.0001), and decreased IGF-I sd scores (r = 0.10, P < 0.001) were independently associated with sBMD.

Conclusions:

Hormone variables associated with lower sBMD in patients with adult-onset GHD include unreplaced sex steroid deficiency and corticotropin deficiency in the LS and lower IGF-I SDS in the FN.
Diagnosis and Treatment of Subclinical Hypercortisolism
Authors: Chiodini Iacopo
Published: March 2011

Context:

Subclinical hypercortisolism (SH) is a condition of biochemical cortisol excess without the classical signs or symptoms of overt hypercortisolism. It is thought to be present in the 5–30% of patients with incidentally discovered adrenal mass (adrenal incidentalomas), which in turn are found in 4–7% of the adult population. Therefore, SH has been suggested to be present in 0.2–2.0% of the adult population. Some studies suggested that this condition is present in 1–10% of patients with diabetes or established osteoporosis. The present manuscript reviews the literature on diagnostic procedures and the metabolic effect of the recovery from SH.

Evidence Acquisition:

A PubMed search was used to identify the available studies. The most relevant studies from 1992 to November 2010 have been included in the review.

Evidence Synthesis:

The available data suggest that SH may be associated with chronic complications, such as hypertension, diabetes mellitus, overweight/obesity, and osteoporosis. The available intervention studies suggest that the recovery from SH may lead to the improvement of hypertension and diabetes mellitus. A retrospective study suggests that this beneficial effect could be predicted before surgery.

Conclusions:

SH is suggested to be associated with some chronic complications of overt cortisol excess. Recovery from this condition seems to improve these complications. However, a large, prospective, randomized study is needed to confirm this hypothesis and to establish the best diagnostic approach to identify patients with adrenal incidentalomas who can benefit from surgery.
Sox9 sustains chondrocyte survival and hypertrophy in part through Pik3ca-Akt pathways
Authors: Ikegami Daisuke , Akiyama Haruhiko , Suzuki Akira , Nakamura Takashi , Nakano Toru , Yoshikawa Hideki , Tsumaki Noriyuki
Published: March 2011

During endochondral bone formation, Sox9 expression starts in mesenchymal progenitors, continues in the round and flat chondrocyte stages at high levels, and ceases just prior to the hypertrophic chondrocyte stage. Sox9 is important in mesenchymal progenitors for their differentiation into chondrocytes, but its functions post-differentiation have not been determined. To investigate Sox9 function in chondrocytes, we deleted mouse Sox9 at two different steps after chondrocyte differentiation. Sox9 inactivation in round chondrocytes resulted in a loss of Col2a1 expression and in apoptosis. Sox9 inactivation in flat chondrocytes caused immediate terminal maturation without hypertrophy and with excessive apoptosis. Inactivation of Sox9 in the last few cell layers resulted in the absence of Col10a1 expression, suggesting that continued expression of Sox9 just prior to hypertrophy is necessary for chondrocyte hypertrophy. SOX9 knockdown also caused apoptosis of human chondrosarcoma SW1353 cells. These phenotypes were associated with reduced Akt phosphorylation. Forced phosphorylation of Akt by Pten inactivation partially restored Col10a1 expression and cell survival in Sox9floxdel/floxdel mouse chondrocytes, suggesting that phosphorylated Akt mediates chondrocyte survival and hypertrophy induced by Sox9. When the molecular mechanism of Sox9-induced Akt phosphorylation was examined, we found that expression of the PI3K subunit Pik3ca (p110α) was decreased in Sox9floxdel/floxdel mouse chondrocytes. Sox9 binds to the promoter and enhances the transcriptional activities of Pik3ca. Thus, continued expression of Sox9 in differentiated chondrocytes is essential for subsequent hypertrophy and sustains chondrocyte-specific survival mechanisms by binding to the Pik3ca promoter, inducing Akt phosphorylation.
Clonal analysis by distinct viral vectors identifies bona fide neural stem cells in the adult zebrafish telencephalon and characterizes their division properties and fate
Authors: Rothenaigner Ina , Krecsmarik Monika , Hayes John A. , Bahn Brigitte , Lepier Alexandra , Fortin Gilles , Götz Magdalena , Jagasia Ravi , Bally-Cuif Laure
Published: March 2011

Neurogenesis is widespread in the zebrafish adult brain through the maintenance of active germinal niches. To characterize which progenitor properties correlate with this extensive neurogenic potential, we set up a method that allows progenitor cell transduction and tracing in the adult zebrafish brain using GFP-encoding retro- and lentiviruses. The telencephalic germinal zone of the zebrafish comprises quiescent radial glial progenitors and actively dividing neuroblasts. Making use of the power of clonal viral vector-based analysis, we demonstrate that these progenitors follow different division modes and fates: neuroblasts primarily undergo a limited amplification phase followed by symmetric neurogenic divisions; by contrast, radial glia are capable at the single cell level of both self-renewing and generating different cell types, and hence exhibit bona fide neural stem cell (NSC) properties in vivo. We also show that radial glial cells predominantly undergo symmetric gliogenic divisions, which amplify this NSC pool and may account for its long-lasting maintenance. We further demonstrate that blocking Notch signaling results in a significant increase in proliferating cells and in the numbers of clones, but does not affect clone composition, demonstrating that Notch primarily controls proliferation rather than cell fate. Finally, through long-term tracing, we illustrate the functional integration of newborn neurons in forebrain adult circuitries. These results characterize fundamental aspects of adult progenitor cells and neurogenesis, and open the way to using virus-based technologies for stable genetic manipulations and clonal analyses in the zebrafish adult brain.
Strigolactones regulate protonema branching and act as a quorum sensing-like signal in the moss Physcomitrella patens
Authors: Proust Hélène , Hoffmann Beate , Xie Xiaonan , Yoneyama Kaori , Schaefer Didier G. , Yoneyama Koichi , Nogué Fabien , Rameau Catherine
Published: March 2011

Strigolactones are a novel class of plant hormones controlling shoot branching in seed plants. They also signal host root proximity during symbiotic and parasitic interactions. To gain a better understanding of the origin of strigolactone functions, we characterised a moss mutant strongly affected in strigolactone biosynthesis following deletion of the CAROTENOID CLEAVAGE DIOXYGENASE 8 (CCD8) gene. Here, we show that wild-type Physcomitrella patens produces and releases strigolactones into the medium where they control branching of protonemal filaments and colony extension. We further show that Ppccd8 mutant colonies fail to sense the proximity of neighbouring colonies, which in wild-type plants causes the arrest of colony extension. The mutant phenotype is rescued when grown in the proximity of wild-type colonies, by exogenous supply of synthetic strigolactones or by ectopic expression of seed plant CCD8. Thus, our data demonstrate for the first time that Bryophytes (P. patens) produce strigolactones that act as signalling factors controlling developmental and potentially ecophysiological processes. We propose that in P. patens, strigolactones are reminiscent of quorum-sensing molecules used by bacteria to communicate with one another.
Effects of an oral supplementation of germinated barley foodstuff on serum tumour necrosis factor-α, interleukin-6 and -8 in patients with ulcerative colitis
Authors: Faghfoori Zeinab , Navai Lida , Shakerhosseini Rahebeh , Somi Mohammad Hossein , Nikniaz Zeinab , Norouzi Mohammad Fahmideh
Published: March 2011

Background

The efficacy of germinated barley foodstuff (GBF) on tumour necrosis factor-alpha (TNF- α), interleukin-6 (IL-6) and -8 (IL-8) in patients with ulcerative colitis (UC) has not yet been examined. The aim of the present study was to determine the effect of administration of GBF on serum TNF- α, IL-6 and -8 levels in UC patients in remission.

Methods

Forty-one patients with UC were divided into two groups, namely control and GBF group. Twenty-one patients in the control group received standard treatment while 20 patients in the GBF group received 30 g of GBF daily by oral administration during two months of the study along with standard drug therapy.

Results

Levels of TNF- α, IL-6 and -8 all decreased in the GBF group compared with baseline during the two-month study, while in the control group all values rose. For IL-6 and -8 this effect was significant, P = 0.034 and 0.013, respectively.

Conclusions

The results of the present study showed that the consumption of GBF may reduce the level of serum TNF- α, IL-6 and -8 in patients with UC. This investigation was designed as a pilot study and the results may provide a basis for more future clinical trials.
Measurement of serum lanthanum in patients treated with lanthanum carbonate by inductively coupled plasma-mass spectrometry
Authors: Handley S A , Raja K B , Sharpe C , Flanagan R J
Published: March 2011

Background

Lanthanum carbonate is used as a phosphate binder in patients with stage V chronic kidney disease (CKD). While well tolerated in clinical trials, with no toxicity reported as regards bone and liver metabolism, and cognitive function, concerns remain over possible toxicity. Published methods for the measurement of lanthanum ion in biological samples include aggressive and complicated sample preparation steps that are unsuitable for routine use. A simple method has been developed and validated for the measurement of serum lanthanum.

Method

A ThermoFisher Scientific XSERIES-II inductively coupled plasma-mass spectrometer was used to monitor 139La. Validation was undertaken using internal quality control solutions containing lanthanum ion (0.20, 0.70 and 4.00 μg/L). Lanthanum was measured in patients (number = 20) with CKD prescribed lanthanum carbonate (500–1500 mg/d) and patients undergoing haemodialysis not prescribed lanthanum carbonate (number = 20).

Results

Accuracy and imprecision were >95% and <5%, respectively. Calibration was linear (range 0.1–5 μg/L, R2 = 0.99). The lower limit of quantification (LLoQ) was 0.1 μg/L lanthanum ion. In patients with CKD not prescribed lanthanum carbonate, serum lanthanum was below the LLoQ. Out of 20 CKD patients prescribed lanthanum carbonate, serum lanthanum was measurable in only 12 (range 0.11–0.60 μg/L lanthanum ion). There was no apparent relationship between dose and serum lanthanum in these patients.

Conclusions

A lack of relationship between the dose of lanthanum carbonate and the serum lanthanum concentration may have been due to poor adherence to the treatment regimen. However the concentrations measured were close to the LLoQ.
Clinical quality indicators in laboratory medicine: a survey of current practice in the UK
Authors: Barth Julian H
Published: March 2011

Background

Clinical outcomes are the current paradigm for assessing the performance of health institutions. In contrast, clinical laboratories are assessed on largely operational criteria.

Methods

An invitation to an online questionnaire was sent to all members of the Association for Clinical Biochemistry in the UK and Eire. All data were normalized to the total number of respondents irrespective of how many respondents answered each question.

Results

A total of 335 individuals responded to the survey. A further six responses were discarded as the respondents worked outside clinical laboratories. Overall responses showed that of the selected quality indicators, responses ranged from 7% to 84%. In general, although most laboratories provided an advisory and interpretative service, there was little evaluation and audit of this component of the service. The majority of respondents reported a written critical (alert) list and a hospital point-of-care committee.

Conclusion

This survey has explored clinical quality indicators in the preanalytical, analytical and postanalytical phases of laboratory practice. This should act as a template for laboratory assessment and clinical quality improvement.
Measuring carbonic anhydrase IX as a hypoxia biomarker: differences in concentrations in serum and plasma using a commercial enzyme-linked immunosorbent assay due to influences of metal ions
Authors: Wind Tobias C , Messenger Michael P , Thompson Douglas , Selby Peter J , Banks Rosamonde E
Published: March 2011

Background

There is increasing interest in measuring the soluble forms of carbonic anhydrase IX (CA IX) in blood as a marker of hypoxia for prognostic purposes or for predictive use in therapeutic trials in various cancers. Following our initial observations of marked differences in the measured concentrations of CA IX in EDTA plasma versus serum, we sought to investigate these further in order to determine their effects on results in published studies and to ensure accurate measurement in future studies.

Methods

Serum and EDTA plasma samples from healthy controls and patients with renal cancer were used in the validation of two commercially available enzyme-linked immunosorbent assays (ELISAs) for CA IX with examination of recovery, parallelism and specificity and comparison of paired plasma and serum.

Results

Successful validation of one of the ELISAs was not achieved with particular problems with parallelism and marked differences in measured CA IX concentrations between EDTA plasma and serum. This appeared to be due to a metal ion-dependent epitope on CA IX recognized by the detection antibody in this assay. The other commercially available ELISA examined was successfully validated and showed no difference in CA IX between EDTA plasma and serum.

Conclusions

These results have important consequences for published studies using this assay where the conclusions drawn from the measurements made may be invalid. This study highlights the need for stringent validation of commercially available assays, including examination of various sample types, before use in research studies.