Cloning and functional characterization of LCR-F1: a bZIP transcription factor that activates erythroid-specific,human globin gene expression.

DNase I hypersensitive site 2 (HS 2) of the human beta-globin Locus Control Region (LCR) directs high level expression of the beta-globin gene located 50 kilobases downstream. Experiments in cultured cells and in transgenic mice demonstrate that duplicated AP1-like sites in HS 2 are required for this powerful enhancer activity. A cDNA clone encoding a basic, leucine-zipper protein that binds to these sites was isolated and designated Locus Control Region-Factor 1 (LCR-F1). This protein is a member of a new family of regulatory factors that contain a 63 amino acid ''CNC domain'' overlapping the basic region. This domain is approximately 70% identical in the Drosophila Cap N Collar (CNC) protein, NF-E2 and LCR-F1. LCR-F1 transactivates an HS 2/gamma-globin reporter gene over 170-fold in transient transfection experiments specifically in erythroid cells. These results suggest that LCR-F1 may be a critical factor involved in LCR-mediated, human globin gene expression.     

Immunity to type XI collagen in mice. Evidence that the alpha 3(XI) chain of type XI collagen and the alpha 1(II) chain of type II collagen share arthritogenic determinants and induce arthritis in DBA/1 mice.

To determine whether native bovine type XI collagen (BXI) is arthritogenic, five strains of inbred mice were immunized with BXI/CFA. Arthritis was not observed in any of these strains, though it was prevalent in DBA/1 and B10.RIII controls immunized with bovine type II collagen (BII). Antisera from BXI-immunized mice reacted with mouse type XI collagen (MsXI), weakly with the alpha-chains of BXI, and minimally with mouse type II collagen (MsII). However, antisera to BII reacted with MsII and MsXI, indicating antibodies to conformation-independent epitopes shared by alpha 1(II) and alpha 3(XI). Mice immunized with BXI containing a small amount of BII developed arthritis much like those immunized with BII; sera from these mice reacted with MsXI and MsII. Delayed-type hypersensitivity responses differed from IgG responses, i.e., BXI elicited responses to alpha 1(XI), alpha 2(XI), alpha 3(XI), and alpha 1(II); BII, to alpha 3(XI) and alpha 1(II) exclusively. To determine whether alpha 1(XI), alpha 2(XI), alpha 3(XI), and alpha 1(II) are arthritogenic, DBA/1J mice were immunized with each alpha-chain. Arthritis was seen in mice injected with alpha 3(XI) or alpha 1(II). Sera to both alpha-chains reacted similarly with MsII and peptide fragment alpha 1(II)-CB11. Epitope mapping using polyclonal and mAb to type II collagen revealed that all polyclonal and 11 of 14 mAb reacted with alpha 3(XI) and alpha 1(II), whereas three mAb reacted only with alpha 1(II). In conclusion, BXI is immunogenic but not arthritogenic in five strains of mice, whereas alpha 3(XI) and alpha 1(II) are arthritogenic and immunogenic in DBA/1 mice and share greater than or equal to 11 epitopes recognized by autoantibody.     

Inhibition of dopamine beta-hydroxylase by bidentate chelating agents

1-2H-Phthalazine hydrazone (hydralazine; HYD), 2-1H-pyridinone hydrazone (2-hydrazinopyridine; HP), 2-quinoline-carboxylic acid (QCA), 1-isoquinolinecarboxylic acid (IQCA), 2,2'-bi-1H-imidazole (2,2'-biimidazole; BI), and 1H-imidazole-4-acetic acid (imidazole-4-acetic acid; IAA) directly and reversibly inhibit homogeneous soluble bovine dopamine beta-hydroxylase (3,4-dihydroxyphenethylamine, ascorbate:oxygen oxidoreductase (beta-hydroxylating), EC 1.14.17.1). HYD, QCA and IAA show competitive allosteric inhibition of dopamine beta-hydroxylase with respect to ascorbate (Kis = 5.7(+/- 0.9) microM, 0.14(+/- 0.03) mM, 0.80(+/- 0.20) mM; nH = 1.4(+/- 0.1), 1.8(+/- 0.4), 2.8(+/- 0.6), respectively). HYD and IAA show slope and intercept mixed-type allosteric inhibition of dopamine beta-hydroxylase with respect to tyramine. QCA shows allosteric uncompetitive inhibition of dopamine beta-hydroxylase with respect to tyramine. HP, BI and IQCA all show linear competitive inhibition (Kis = 1.9(+/- 0.3) microM, 21(+/- 6) microM, and 0.9(+/- 0.3) microM, respectively) with respect to ascorbate. HP and BI show linear mixed-type while IQCA shows linear uncompetitive inhibition of dopamine beta-hydroxylase with respect to tyramine. In the presence of HP, HYD or IAA intersecting double-reciprocal plots of the initial velocity as a function of tyramine concentration at differing fixed levels of ascorbate are observed. These findings are consistent with a uni-uni-ping-pong-ter-bi kinetic mechanism for dopamine beta-hydroxylase that involves a ternary enzyme-ascorbate-tyramine-oxygen complex. The results for HYD, QCA and IAA are the first examples of allosteric inhibitor interactions with dopamine beta-hydroxylase.     

Amylase polymorphism: studies of sera and duodenal aspirates in normal individuals and in cystic fibrosis.

Prior genetic studies of the human pancreatic amylase (Amy2) locus have been directed principally to the electrophoretic analysis of serum and urine, on the assumption that these fluids receive negligible contributions from the salivary (Amy 1) locus. In support of that assumption was the observation that the isozyme bands were lacking in patients with cystic fibrosis and in a postpancreatectomy patient. We have examined the sera of 97 patients having cystic fibrosis and find normal levels of serum amylase. On electrophoresis, three-quarters of the cystic fibrosis patients have a pattern (F-pattern) not observed in normal sera. The pattern is characterized by the absence of Pa 1. Comparative electrophoresis and mixing experiments indicate that the F-pattern is of salivary origin and is unmasked in cystic fibrosis by the absence of a pancreatic contribution. The normal serum pattern is considered to be an admixture of salivary and pancreatic amylase. On the assumption that duodenal fluids might more closely reflect the pancreatic (Amy 2) locus, electrophoretic studies were performed on 148 normal individuals and 37 individuals with cystic fibrosis. Electrophoretic phenotypes in duodenal aspirates are more complex than previously reported in studies of urine and serum; presumably because of the higher concentrations of amylase in the aspirates. Comparative electrophoresis and mixing experiments indicate that the phenotypes observed in duodenal aspirates also reflect admixture of pancreatic and salivary amylase. This recognition of pancreatic and salivary admixture in sera fortunately does not alter our prior understanding of the genetics of the Amy 2 polymorphism. The extensive studies which led to the delineation of the Amy 2 polymorphism were essentially based on the presence or absence of a variant band which proves now to be outside the zone of admixture.     

Breast MRI in nonpalpable breast lesions: a randomized trial with diagnostic and therapeutic outcome – MONET – study

Background

In orthodontic treatment, anchorage control is a fundamental aspect. Usually conventional mechanism for orthodontic anchorage control can be either extraoral or intraoral that is headgear or intermaxillary elastics. Their use are combined with various side effects such as tipping of occlusal plane or undesirable movements of teeth. Especially in cases, where key-teeth are missing, conventional anchorage defined as tooth-borne anchorage will meet limitations. Therefore, the use of endosseous implants for anchorage purposes are increasingly used to achieve positional stability and maximum anchorage.

Methods/Design

The intended study is designed as a prospective, multicenter randomized controlled trial (RCT), comparing and contrasting the effect of early loading of palatal implant therapy versus implant loading after 12 weeks post implantation using the new ortho-implant type II anchor system device (Orthosystem Straumann, Basel, Switzerland). 124 participants, mainly adult males or females, whose diagnoses require temporary stationary implant-based anchorage treatment will be randomized 1:1 to one of two treatment groups: group 1 will receive a loading of implant standard therapy after a healing period of 12 week (gold standard), whereas group 2 will receive an early loading of orthodontic implants within 1 week after implant insertion. Participants will be at least followed for 12 months after implant placement. The primary endpoint is to investigate the behavior of early loaded palatal implants in order to find out if shorter healing periods might be justified to accelerate active orthodontic treatment. Secondary outcomes will focus e.g. on achievement of orthodontic treatment goals and quantity of direct implant-bone interface of removed bone specimens. As tertiary objective, a histologic and microtomography evaluation of all retrieved implants will be performed to obtain data on the performance of the SLA surface in human bone evaluation of all retrieved implants. Additionally, resonance frequency analysis (RFA, Osstell? mentor) will be used at different times for clinically monitoring the implant stability and for histological comparison in order to measure the reliability of the resonance frequency measuring device.

Trial registration

Current Controlled Trials ISRCTN97142521.     

The development of new bicyclic pyrazole-based cytokine synthesis inhibitors

4-Aryl-5-pyrimidyl-based cytokine synthesis inhibitors of TNF-alpha production, which contain a novel bicyclic pyrazole heterocyclic core, are described. Many of these inhibitors showed low nanomolar activity against LPS-induced TNF-alpha production in a THP-1 cell-based assay and against human p38 alpha MAP kinase in an isolated enzyme assay. The X-ray crystal structure of a bicyclic pyrazole inhibitor co-crystallized with mutated p38 (mp38) is presented.     

Nitric oxide-dependent generation of reactive species in sickle cell disease. Actin tyrosine induces defective cytoskeletal polymerization

The intermittent vascular occlusion occurring in sickle cell disease (SCD) leads to ischemia-reperfusion injury and activation of inflammatory processes including enhanced production of reactive oxygen species and increased expression of inducible nitric-oxide synthase (NOS2). Appreciating that impaired nitric oxide-dependent vascular function and the concomitant formation of oxidizing and nitrating species occur in concert with increased rates of tissue reactive oxygen species production, liver and kidney NOS2 expression, tissue 3-nitrotyrosine (NO(2)Tyr) formation and apoptosis were evaluated in human SCD tissues and a murine model of SCD. Liver and kidney NOS2 expression and NO(2)Tyr immunoreactivity were significantly increased in SCD mice and humans, but not in nondiseased tissues. TdT-mediated nick end-label (TUNEL) staining showed apoptotic cells in regions expressing elevated levels of NOS2 and NO(2)Tyr in all SCD tissues. Gas chromatography mass spectrometry analysis revealed increased plasma protein NO(2)Tyr content and increased levels of hepatic and renal protein NO(2)Tyr derivatives in SCD (21.4 +/- 2.6 and 37.5 +/- 7.8 ng/mg) versus wild type mice (8.2 +/- 2.2 and 10 +/- 1.2 ng/mg), respectively. Western blot analysis and immunoprecipitation of SCD mouse liver and kidney proteins revealed one principal NO(2)Tyr-containing protein of 42 kDa, compared with controls. Enzymatic in-gel digestion and MALDI-TOF mass spectrometry identified this nitrated protein as actin. Electrospray ionization and fragment analysis by tandem mass spectrometry revealed that 3 of 15 actin tyrosine residues are nitrated (Tyr(91), Tyr(198), and Tyr(240)) at positions that significantly modify actin assembly. Confocal microscopy of SCD human and mouse tissues revealed that nitration led to morphologically distinct disorganization of filamentous actin. In aggregate, we have observed that the hemoglobin point mutation of sickle cell disease that mediates hemoglobin polymerization defects is translated, via inflammatory oxidant reactions, into defective cytoskeletal polymerization.     

Successful immunotherapy with matrix metalloproteinase-derived peptides in adjuvant arthritis depends on the timing of peptide administration

We have recently found that matrix metalloproteinases (MMPs) are targets for T-cell and B-cell reactivity in experimental arthritis. In the present article, we investigate whether modulation of MMP-specific T-cell responses could influence the course of adjuvant arthritis (AA). Lewis rats were treated nasally with MMP peptides prior to or after AA induction. Administration of the MMP-10 or the MMP-16 peptide prior to AA induction reduced the arthritic symptoms. In contrast, administration of the MMP-10 peptide after AA induction aggravated the arthritic symptoms. The present study shows the possible usefulness of MMP peptides for immunotherapy. However, a clear understanding of proper timing of peptide administration is crucial for the development of such therapies.     

Rapid Genotyping of Mice with Hemoglobinopathies and Globin Transgenes

The hematology of the laboratory mouse has beenwell characterized. Normal genetic differences at thealpha- and beta-globin gene loci serve as useful markersfor a wide variety of types of experimental studies. There are a number of naturallyoccurring or induced mutations that disrupt globinexpression and produce thalassemic phenotypes. Inaddition, much has been learned of the workings of theglobin locus control region from studies of transgenicmice, including those with mutations induced by targetedsite-specific modifications. After a new mutation ortransgene has been created, it must be maintained in living mice, and the genotypes of theoffspring must be ascertained. While it is possible todetermine genotypes by DNA analyses, such assays aretime consuming and relatively expensive. An osmoticchallenge test -- originally developed for thegenotyping of large-deletion alpha-thalassemia mutationsin mice -- has proven useful in detecting bothsevere and milder alpha- and beta-thalassemias, as wellas some transgenic genotypes in mice carrying human globin genes.Reliable genotyping can, in some cases, be completedwithin a few minutes with minimal expense.Quantification of red cell fragility for a variety ofthalassemic and transgenic mice is described here, alongwith a simplified test suitable for rapid, routinegenotyping. The osmotic challenge test is perfectlyreliable for distinguishing genotypes that causesignificantly decreased release of hemoglobin from the redcells, but it is also useful for some of the conditionsin which overall erythrocyte osmotic fragility isessentially normal.