Three-compartment wrist arthrography: use of a low-iodine-concentration contrast agent to decrease study time

To decrease examination time, the authors used a contrast agent with a low iodine concentration for three-compartment (radiocarpal joint, distal radioulnar joint, midcarpal compartment) wrist arthrography. The material was used in 24 patients. Many patients demonstrated dissipation of contrast material in the radiocarpal joint by 30 minutes after injection. By 45 minutes, all patients demonstrated sufficient dissipation to permit the second injection. The technique produces diagnostic images and reduces the time required for the study.     

复方鱼腥草口服液质控项目的研究

目的：建立复方鱼腥草口服液质量控制项目。方法：用聚酰胺薄层色谱法对口服液中的主要成分之一绿原酸进行定性鉴别。用ＲＰ－ＨＰＬＣ法对黄芩苷进行含量测定。采用ＯＤＳ柱,流动相为甲醇－０．２％磷酸水溶液（５２：４８）。结果：线性范围０．１６２４～１．６２４ｕｇ。平均回收率为１０１．６％,ＲＳＤ＝１．２％。结论：上述方法简便、重复性好。可用于本品的质量控制。     

Genome-wide association with select biomarker traits in the Framingham Heart Study

Background

Systemic biomarkers provide insights into disease pathogenesis, diagnosis, and risk stratification. Many systemic biomarker concentrations are heritable phenotypes. Genome-wide association studies (GWAS) provide mechanisms to investigate the genetic contributions to biomarker variability unconstrained by current knowledge of physiological relations.

Methods

We examined the association of Affymetrix 100K GeneChip single nucleotide polymorphisms (SNPs) to 22 systemic biomarker concentrations in 4 biological domains: inflammation/oxidative stress; natriuretic peptides; liver function; and vitamins. Related members of the Framingham Offspring cohort (n = 1012; mean age 59 ± 10 years, 51% women) had both phenotype and genotype data (minimum-maximum per phenotype n = 507–1008). We used Generalized Estimating Equations (GEE), Family Based Association Tests (FBAT) and variance components linkage to relate SNPs to multivariable-adjusted biomarker residuals. Autosomal SNPs (n = 70,987) meeting the following criteria were studied: minor allele frequency ≥ 10%, call rate ≥ 80% and Hardy-Weinberg equilibrium p ≥ 0.001.

Results

With GEE, 58 SNPs had p < 10^-6: the top SNPs were rs2494250 (p = 1.00*10^-14) and rs4128725 (p = 3.68*10^-12) for monocyte chemoattractant protein-1 (MCP1), and rs2794520 (p = 2.83*10^-8) and rs2808629 (p = 3.19*10^-8) for C-reactive protein (CRP) averaged from 3 examinations (over about 20 years). With FBAT, 11 SNPs had p < 10^-6: the top SNPs were the same for MCP1 (rs4128725, p = 3.28*10^-8, and rs2494250, p = 3.55*10^-8), and also included B-type natriuretic peptide (rs437021, p = 1.01*10^-6) and Vitamin K percent undercarboxylated osteocalcin (rs2052028, p = 1.07*10^-6). The peak LOD (logarithm of the odds) scores were for MCP1 (4.38, chromosome 1) and CRP (3.28, chromosome 1; previously described) concentrations; of note the 1.5 support interval included the MCP1 and CRP SNPs reported above (GEE model). Previous candidate SNP associations with circulating CRP concentrations were replicated at p < 0.05; the SNPs rs2794520 and rs2808629 are in linkage disequilibrium with previously reported SNPs. GEE, FBAT and linkage results are posted at http://www.ncbi.nlm.nih.gov/projects/gap/cgi-bin/study.cgi?id=phs000007.

Conclusion

The Framingham GWAS represents a resource to describe potentially novel genetic influences on systemic biomarker variability. The newly described associations will need to be replicated in other studies.

     

Mapping of monoclonal antibodies to human factor IX

We used recombinant DNA techniques to map a panel of six monoclonal antibodies (MoAbs) to regions of the human factor IX molecule. A-2 maps to 17 amino acids at the amino terminus of the heavy chain of IXa; 2D5, an inhibitor of clotting, is defined to 36 amino acids of the first EGF- like domain of human factor IX. A-4, A-5, C10D, and FXC008 all map to a region of the heavy chain containing amino acids 180 through 310, suggesting an immunodominant site. FXC008 has been reported to interfere with binding of factor IXa to factor VIII:Ca.     

Complement-induced vesiculation and exposure of membrane prothrombinase sites in platelets of paroxysmal nocturnal hemoglobinuria

Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired stem-cell disorder in which the glycolipid-anchored membrane proteins, including the cell-surface complement inhibitors, CD55 and CD59, are partially or completely deleted from the plasma membranes of mature blood cells. To gain insight into the pathogenesis of thrombosis that is frequently observed in this disorder, the procoagulant responses of PNH platelets exposed to the human terminal complement proteins C5b-9 were investigated. C5b-9 complexes were assembled on gel-filtered platelets by incubation with purified C5b6, C7, C9, and limiting amounts of C8. Platelet microparticle formation and exposure of plasma membrane- binding sites for coagulation factor Va were then analyzed by flow cytometry. PNH platelets exhibiting undetectable levels of surface CD59 antigen showed an approximately 10-fold increase in sensitivity to C5b- 9-stimulated expression of membrane-binding sites for factor Va when compared with platelets from normal controls. Expression of catalytic surface for the prothrombinase complex (VaXa) paralleled the exposure of factor Va-binding sites; the rate of prothrombin conversion by C5b-9- treated PNH platelets exceeded that of C5b-9-treated normal controls by approximately 10-fold at the maximal input of C8 tested (500 ng/mL). These data indicate that PNH platelets deficient in plasma membrane CD59 antigen are exquisitely sensitive to C5b-9-induced expression of prothrombinase activity, and suggest that the tendency toward thrombosis in these patients may be due, at least in part, to the deletion of this complement inhibitor from the platelet plasma membrane.     

Effect of low-dose prednisone (with calcium and calcitriol supplementation) on calcium and bone metabolism in healthy volunteers

The administration of moderate to high doses of corticosteroids is associated with bone loss. This probably results from the uncoupling of bone formation (decreased) and bone resorption (unchanged or increased). We examined the effect of low-dose (10 mg/day) prednisone (LDP) and the possible mitigating effects of calcium and 1.25 (OH)2 vitamin D (calcitriol) on calcium and bone metabolism in eight healthy, young male volunteers. The study consisted of four observation periods: in the first period, LDP was prescribed during 1 week; in the second, third and fourth periods, calcium (500 mg/day), calcitriol (0.5 micrograms b.i.d.) and calcium in combination with calcitriol, respectively, were added to LDP. Bone formation was measured by means of serum osteocalcin, carboxy-terminal propeptide of type 1 procollagen (P1CP) and alkaline phosphatase, bone resorption by means of urinary excretion of calcium, hydroxyproline, (free and total) pyridinoline, (free and total) deoxypyridinoline and serum carboxy-terminal cross- linked telopeptide of type 1 collagen (1CTP). Dietary calcium and sodium intake were maintained at a stable level during the entire study period. Treatment with LDP led to a decrease in osteocalcin, P1CP and alkaline phosphatase (all P < 0.01). Urinary excretion of pyridinolines, hydroxyproline and serum 1CTP did not increase, but remained unchanged or slightly reduced (P < 0.05), depending on the time of measurement and the marker of bone resorption. Parathyroid hormone (PTH) (insignificantly) increased during LDP (+19%) and LDP plus calcium (+14%), but decreased during supplementation with calcitriol (-16%) and calcium/calcitriol (-44%; P < 0.01). Urinary excretion of calcium increased during treatment with LDP and calcitriol (P < 0.05) and calcium/calcitriol (P < 0.05). It is concluded that LDP has a negative effect on bone metabolism, since bone formation decreased while bone resorption remained unchanged or decreased slightly. The increase in PTH during LDP could be prevented by calcitriol combined with calcium supplementation.      

Signaling and induction of enhanced cytoadhesiveness via the hematopoietic progenitor cell surface molecule CD34

The transmembrane glycoprotein CD34 shows a highly restricted expression on a crucial subset of hematopoietic cells. We show here that engagement of particular determinants of CD34 can lead to signal transduction and to enhanced adhesiveness of CD34+ hematopoietic cells. Monoclonal antibodies (MoAbs) directed against O-sialoglycoprotease- sensitive epitopes of CD34 (QBEND10, ICH3, BI.3C5, MY10) but not MoAbs against O-sialoglycoprotease-resistant epitopes (9F2, 8G12) induce actin polymerization in KG-1a and KG-1 cells and strongly enhanced cytoadhesiveness. The capacity to induce adhesion requires cellular energy, divalent cations, and intact cytoskeleton but not de novo protein synthesis. The observed cytoadhesion seems at least in part to be caused by a concomitant activation of the beta 2 integrin cytoadhesion pathway. It can be significantly inhibited with lymphocyte function-associated antigen-1 and intercelluar adhesion molecule-1 antibodies. Protein kinase inhibition analyses suggest that the pathways initiated by engagement of the CD34 molecule with certain CD34 MoAbs involves protein tyrosine kinases but that protein kinase C is not critically involved.     

Generation of CD4+ cytotoxic T-lymphocyte clones from a patient with severe graft-versus-host disease after allogeneic bone marrow transplantation: implications for graft-versus-leukemia reactivity

HLA-identical bone marrow transplantation (BMT) is associated with both graft-versus-host disease (GVHD) and graft-versus-leukemia (GVL) reactivity. Different T-cell subsets from the bone marrow (BM) graft may be responsible for GVHD and GVL reactivity after BMT. In the etiology of GVHD, not only CD8+ but also CD4+ donor T lymphocytes may play an important role. Here we report a patient with chronic myeloid leukemia (CML) who was transplanted with the BM from his HLA- genotypically identical sister. After BMT there was complete engraftment, but the patient died because of acute GVHD grade III-IV in complete remission. Cytotoxic T-lymphocyte (CTL) lines were generated after BMT using the irradiated leukemic cells from the patient as stimulator cells and the donor-originated peripheral blood mononuclear cells, procured from the patient after BMT, as responder cells. The generated CTL lines showed specific lysis of the recipient lymphocytes and leukemic cells in a 51Cr release assay. Two types of CTL clones could be established from these CTL lines, both phenotypically CD4+. Clone type I showed male-specific HLA-DQ5-restricted lysis of the recipient lymphocytes, but not of the circulating relatively mature leukemic cells from the patient. This may be explained by the low HLA- DQ5 expression of the more mature CML cells. Clone type II showed HLA- DR2-restricted minor histocompatibility antigen-specific lysis of the recipient lymphocytes and leukemic cells. Both types of CTL clones showed antigen-specific cell-mediated growth inhibition of the recipient clonogenic leukemic precursor cells. These CD4+ CTL clones produced several activating cytokines including tumor necrosis factor alpha, interferon gamma, granulocyte-macrophage colony-stimulating factor (GM-CSF), and macrophage CSF. Our results illustrate that these CD4+ CTL clones may have induced GVHD directly by cytolysis and indirectly by activating cytokines. Because both types of CTL clones recognized the recipient leukemic progenitor cells, they may also contribute to GVL reactivity after BMT.