Transfusion errors in New York State: an analysis of 10 years' experience

BACKGROUND

While public focus is on the risk of infectious disease from the blood supply, transfusion errors also contribute significantly to adverse outcomes. This study characterizes such errors.

STUDY DESIGN AND METHODS

The New York State Department of Health mandates the reporting of transfusion errors by the approximately 256 transfusion services licensed to operate in the state. Each incident from 1990 through 1998 that resulted in administration of blood to other than the intended patient or the issuance of blood of incorrect ABO or Rh group for transfusion was analyzed.

RESULTS

Erroneous administration was observed for 1 of 19, 000 RBC units administered. Half of these events occurred outside the blood bank (administration to the wrong recipient, 38%; phlebotomy errors, 13%). Isolated blood bank errors, including testing of the wrong specimen, transcription errors, and issuance of the wrong unit, were responsible for 29 percent of events. Many events (15%) involved multiple errors; the most common was failure to detect at the bedside that an incorrect unit had been issued.

CONCLUSION

Transfusion error continues to be a significant risk. Most errors result from human actions and thus may be preventable. The majority of events occur outside the blood bank, which suggests that hospitalwide efforts at prevention may be required.

Central role of immunoglobulin (Ig) E in the induction of lung eosinophil infiltration and T helper 2 cell cytokine production: inhibition by a non-anaphylactogenic anti-IgE antibody

Elevated levels of immunoglobulin (Ig) E are associated with bronchial asthma, a disease characterized by eosinophilic inflammation of the airways. Activation of antigen-specific T helper (Th) 2 cells in the lung with the subsequent release of interleukin (IL) 4 and IL-5 is believed to play an important role in the pathogenesis of this disease. In this study, we have used a non-anaphylactogenic anti-mouse-IgE antibody to investigate the relationship between IgE, airway eosinophil infiltration, and the production of Th2 cytokines. Immunization of mice with house dust mite antigen increased serum levels of IgE and IgG. Antigen challenge of immunized but not control mice induced an infiltration of eosinophils in the bronchoalveolar lavage associated with the production of IL-4 and IL-5 from lung purified Thy1.2+ cells activated through the CD3-T cell receptor complex. Administration of the anti-IgE monoclonal antibody (mAb) 6h before antigen challenge neutralized serum IgE but not IgG and inhibited the recruitment of eosinophils into the lungs and the production of IL-4 and IL-5 but not interferon gamma. Studies performed using an anti-CD23 mAb, CD23 deficient and mast cell deficient mice suggest that anti-IgE mAb suppresses eosinophil infiltration and Th2 cytokine production by inhibiting IgE-CD23-facilitated antigen presentation to T cells. Our results demonstrate that IgE-dependent mechanisms are important in the induction of a Th2 immune response and the subsequent infiltration of eosinophils into the airways. Neutralization of IgE, for example, non-anaphylactogenic anti-IgE mAbs may provide a novel therapeutic approach to the treatment of allergic airway disease.

Nitric oxide prevents cardiovascular disease and determines survival in polyglobulic mice overexpressing erythropoietin

Nitric oxide (NO) induces vasodilatatory, antiaggregatory, and antiproliferative effects in vitro. To delineate potential beneficial effects of NO in preventing vascular disease in vivo, we generated transgenic mice overexpressing human erythropoietin. These animals induce polyglobulia known to be associated with a high incidence of vascular disease. Despite hematocrit levels of 80%, adult transgenic mice did not develop hypertension or thromboembolism. Endothelial NO synthase levels, NO-mediated endothelium-dependent relaxation and circulating and vascular tissue NO levels were markedly increased. Administration of the NO synthase inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME) led to vasoconstriction of peripheral resistance vessels, hypertension, and death of transgenic mice, whereas wild-type siblings developed hypertension but did not show increased mortality. L-NAME-treated polyglobulic mice revealed acute left ventricular dilatation and vascular engorgement associated with pulmonary congestion and hemorrhage. In conclusion, we here unequivocally demonstrate that endothelial NO maintains normotension, prevents cardiovascular dysfunction, and critically determines survival in vivo under conditions of increased hematocrit.

Histone acetylation and chromatin remodeling

Chromatin represents a repressive barrier to the process of transcription. This molecular obstacle is a highly dynamic structure, able to compact the DNA of the entire genome into the confines of a nucleus, and yet it allows access to the genetic information held within. The acetylation of histones has emerged as a regulatory mechanism capable of modulating the properties of chromatin and thus the competence of the DNA template for transcriptional activation. The role of acetylation in chromatin remodeling is therefore of paramount importance to our understanding of gene regulation in vivo.

DNA condensation in two dimensions

We have found that divalent electrolyte counterions common in biological cells (Ca(2+), Mg(2+), and Mn(2+) ) can condense anionic DNA molecules confined to two-dimensional cationic surfaces. DNA-condensing agents in vivo include cationic histones and polyamines spermidine and spermine with sufficiently high valence (Z) 3 or larger. In vitro studies show that electrostatic forces between DNA chains in bulk aqueous solution containing divalent counterions remain purely repulsive, and DNA condensation requires counterion valence Z >/= 3. In striking contrast to bulk behavior, synchrotron x-ray diffraction and optical absorption experiments show that above a critical divalent counterion concentration the electrostatic forces between DNA chains adsorbed on surfaces of cationic membranes reverse from repulsive to attractive and lead to a chain collapse transition into a condensed phase of DNA tethered by divalent counterions. This demonstrates the importance of spatial dimensionality to intermolecular interactions where nonspecific counterion-induced electrostatic attractions between the like-charged polyelectrolytes overwhelm the electrostatic repulsions on a surface for Z = 2. This new phase, with a one-dimensional counterion liquid trapped between DNA chains at a density of 0.63 counterions per DNA bp, represents the most compact state of DNA on a surface in vitro and suggests applications in high-density storage of genetic information and organo-metallic materials processing.

The effect of interferon beta-1b treatment on MRI measures of cerebral atrophy in secondary progressive multiple sclerosis. European Study Group on Interferon beta-1b in secondary progressive multiple sclerosis

The recently completed European trial of interferon beta-1b (IFNbeta-1b) in patients with secondary progressive multiple sclerosis (SP multiple sclerosis) has given an opportunity to assess the impact of treatment on cerebral atrophy using serial MRI. Unenhanced T(1)-weighted brain imaging was acquired in a subgroup of 95 patients from five of the European centres; imaging was performed at 6-month intervals from month 0 to month 36. A blinded observer measured cerebral volume on four contiguous 5 mm cerebral hemisphere slices at each time point, using an algorithm with a high level of reproducibility and automation. There was a significant and progressive reduction in cerebral volume in both placebo and treated groups, with a mean reduction of 3.9 and 2.9%, respectively, by month 36 (P = 0.34 between groups). Exploratory subgroup analyses indicated that patients without gadolinium (Gd) enhancement at the baseline had a greater reduction of cerebral volume in the placebo group (mean reduction at month 36: placebo 5.1%, IFNbeta-1b 1.8%, P < 0.05) whereas those with Gd-enhancing lesions showed a trend to greater reduction of cerebral volume if the patient was on IFNbeta-1b (placebo 2.6%, IFNbeta-1b 3.7%; P > 0.05). These results are consistent with ongoing tissue loss in both arms of this study of secondary progressive multiple sclerosis. This finding is concordant with previous observations that disease progression, although delayed, is not halted by IFNbeta. The different pattern seen in patients with and without baseline gadolinium enhancement suggests that part of the cerebral volume reduction observed in IFNbeta-treated patients may be due to the anti-inflammatory/antioedematous effect of the drug. Longer periods of observation and larger groups of patients may be needed to detect the effects of treatment on cerebral atrophy in this population of patients with advanced disease.

In Vivo Killing Capacity of Cytotoxic T Cells Is Limited and Involves Dynamic Interactions and T Cell Cooperativity

According to in vitro assays, T cells are thought to kill rapidly and efficiently, but the efficacy and dynamics of cytotoxic T lymphocyte (CTL)-mediated killing of virus-infected cells in vivo remains elusive. We used two-photon microscopy to quantify CTL-mediated killing in mice infected with herpesviruses or poxviruses. On average, one CTL killed 2–16 virus-infected cells per day as determined by real-time imaging and by mathematical modeling. In contrast, upon virus-induced MHC class I downmodulation, CTLs failed to destroy their targets. During killing, CTLs remained migratory and formed motile kinapses rather than static synapses with targets. Viruses encoding the calcium sensor GCaMP6s revealed strong heterogeneity in individual CTL functional capacity. Furthermore, the probability of death of infected cells increased for those contacted by more than two CTLs, indicative of CTL cooperation. Thus, direct visualization of CTLs during killing of virus-infected cells reveals crucial parameters of CD8⁺ T cell immunity.

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Two-photon imaging indicates that CTLs kill 2–16 virus-infected cells per day

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CTLs form kinapses rather than stable synapses when killing virus-infected cells

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Some CTL contacts trigger long-lasting calcium fluxes in virus-infected cells

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CTLs can cooperate during killing of virus-infected cells

Constitutive expression of the granulocyte-macrophage colony-stimulating factor gene in acute myeloblastic leukemia

Expression of the granulocyte-macrophage colony-stimulating factor (GM-CSF) gene was studied by Northern blot analysis in normal human hematopoietic cells and a series of leukemias. GM-CSF messenger (m)RNA was detected in activated T cells, but not in normal bone marrow cells, monocytes, or nonactivated T cells. In contrast, leukemic cells from 11 of 22 cases of acute myeloblastic leukemia expressed GM-CSF transcripts. Biologically active CSF was detected in supernatant conditioned by 6 of these 11 leukemias. Expression of the GM-CSF gene was not detected in "common" (pre-B cell) acute lymphoblastic leukemia (11 cases tested) or chronic myeloid leukemia (4 cases tested). These results show that the GM-CSF gene is constitutively expressed in a subset of patients with AML, and further suggest that expression of this gene could contribute to the abnormal growth properties characteristic of AML.

Olanzapine versus placebo in the treatment of adolescents with bipolar mania

OBJECTIVE

The purpose of this study was to evaluate the efficacy and safety of olanzapine for the treatment of acute manic or mixed episodes associated with bipolar disorder in adolescents.

METHOD

A 3-week multicenter, parallel, double-blind, randomized placebo-controlled trial was conducted at 24 sites in the United States and two sites in Puerto Rico. The participants were outpatient and inpatient male and female adolescents 13-17 years of age with an acute manic or mixed episode. Subjects received either olanzapine (2.5-20 mg/day [N=107]) or placebo (N=54). The mean change from baseline to endpoint in the Young Mania Rating Scale total score was the primary outcome measure.

RESULTS

The mean baseline-to-endpoint change in the Young Mania Rating Scale total score was significantly greater for patients receiving olanzapine relative to patients receiving placebo, and a greater proportion of olanzapine-treated patients met response and remission criteria (44.8% versus 18.5% and 35.2% versus 11.1%, respectively). The mean baseline-to-endpoint weight change was significantly greater for patients receiving olanzapine relative to patients receiving placebo (3.7 kg versus 0.3 kg), and the incidence of treatment-emergent weight gain > or =7% of baseline was higher for olanzapine-treated patients (41.9% versus 1.9%). The mean baseline-to-endpoint changes in prolactin, fasting glucose, fasting total cholesterol, uric acid, and the hepatic enzymes aspartate transaminase and alanine transaminase were significantly greater in patients treated with olanzapine relative to patients receiving placebo.

CONCLUSIONS

Olanzapine was effective in the treatment of bipolar mania in adolescent patients. Patients treated with olanzapine, however, had significantly greater weight gain and increases in the levels of hepatic enzymes, prolactin, fasting glucose, fasting total cholesterol, and uric acid.

Maternal methylation imprints on human chromosome 15 are established during or after fertilization

Prader-Willi syndrome (PWS) is a neurogenetic disorder that results from the lack of transcripts expressed from the paternal copy of the imprinted chromosomal region 15q11-q13 (refs. 1,2). In some patients, this is associated with a deletion of the SNURF-SNRPN exon 1 region inherited from the paternal grandmother and the presence of a maternal imprint on the paternal chromosome. Assuming that imprints are reset in the germ line, we and others have suggested that this region constitutes part of the 15q imprinting center (IC) and is important for the maternal to paternal imprint switch in the male germ line. Here we report that sperm DNA from two males with an IC deletion had a normal paternal methylation pattern along 15q11-q13. Similar findings were made in a mouse model. Our results indicate that the incorrect maternal methylation imprint in IC deletion patients is established de novo after fertilization. Moreover, we found that CpG-rich regions in SNURF-SNRPN and NDN, which in somatic tissues are methylated on the maternal allele, are hypomethylated in unfertilized human oocytes. Our results indicate that the normal maternal methylation imprints in 15q11-q13 also are established during or after fertilization.

Immunolocalization of type X collagen in normal fetal and adult osteoarthritic cartilage with monoclonal antibodies

For studies on processing and tissue distribution of type X collagen, monoclonal antibodies were prepared against human recombinant collagen type X (hrCol X) and tested by ELISA, immunoblotting and immunohistology. Forty-two clones were obtained which were grouped into four different subsets based on their reactivity against native and denatured hrCol X, pepsin-treated hrCol X, and the C-terminal NC-1 domain. Here we present results obtained with four monoclonal antibodies: Clone X 53, a representative of group I, binds with high affinity to both native and pepsin-digested hrCol X but with low affinity to the NC-1 dimer; monoclonal antibodies of group II and III recognized native and denatured hrCol X but not NC-1; antibodies of group II, but not III, reacted to some extent with pepsin treated hrCol X; one antibody (X 34) was obtained that reacted strongly with the isolated NC-1 dimer and native hrCol X but not with the NC-1 monomer or pepsin-digested hrCol X (group IV). Antibodies of all groups stained specifically the hypertrophic zone of fetal human epiphyseal cartilage. Mab X 53 stained the peri- and extracellular matrix of hypertrophic chondrocytes in the lower hypertrophic zone and in the calcified cartilage core in endochondral bone trabecules, while clone X 34 stained intracellularly and the pericellular matrix. All other tissues or cells of the epiphysis were negative. Antibody X 53 reacted also with canine, murine and guinea pig hypertrophic cartilage in tissue sections, but not with bovine or porcine type X collagen. In sections of osteoarthritic cartilage, clusters of hypertrophic chondrocytes in the deep zone were stained, confirming previous observations on enhanced chondrocyte hypertrophy and type X collagen expression in osteoarthritic articular cartilage.

Oxygen status of lung granulomas in Mycobacterium tuberculosis-infected mice

It is often assumed that Mycobacterium tuberculosis (Mtb)-induced granulomatous lesions, particularly those undergoing central caseation, are anoxic, and that the survival of Mtb in these lesions requires the integrity of its non-oxidative respiratory pathways. Using the hypoxia marker pimonidazole, we now provide immunohistochemical evidence that in the most frequently used animal model system of inbred mice Mtb-induced granulomas, even after more than one year of aerogenic infection, are not severely hypoxic. In contrast, chronic aerosol infection with M. avium strain TMC724 was associated with hypoxia surrounding necrotizing granuloma centres. Direct measurements of oxygen tension with a flexible microelectrode in mouse lungs chronically infected with Mtb disclosed a wide range of oxygen partial pressures in different parts of the lungs which, however, rarely approached the anoxic conditions consistently found in necrotizing tumours. We further show that an Mtb mutant, defective in nitrate reductase (narG) necessary for survival under anaerobic conditions in vitro, can persist in the lungs of chronically infected mice to a similar extent as wild-type Mtb. These findings have important implications for the use of the mouse model of Mtb infection in developing eradication chemotherapy and for evaluating putative mechanisms of chronic persistence and latency of Mtb.

Medial (hamate) facet of the lunate

One hundred sixty-five cadaveric wrists were dissected to assess the incidence of a medial (hamate) facet on the lunate and any associated pathologic conditions. Forty-seven of these specimens and 137 clinical patients' radiographs were reviewed to attempt to recognize and further assess the incidence of a medial (hamate) facet on the lunate. Two types of lunate were identified. Type I, in which there was no medial facet, was evident in 34.5% of the dissected specimens and type II, in which there was a medial facet, was evident in 65.5% of the dissected specimens. The medial facets in the type II lunates ranged from a shallow 1 mm facet to a deep 6 mm facet. Significant cartilage erosion with exposed subchondral bone at the proximal pole of the hamate, which was not identifiable by radiograph, was evident at dissection in 44.4% of the type II lunates, while none (0%) of the type I lunates had such associated hamate pathologic conditions. This type II lunate, with the high incidence of associated hamate pathology, may be an unidentified cause of wrist pain on the ulnar side.

Disruption of a novel gene (IMMP2L) by a breakpoint in 7q31 associated with Tourette syndrome

Gilles de la Tourette syndrome (GTS) is a complex neuropsychiatric disorder characterized by multiple motor and phonic tics. We identified a male patient with GTS and other anomalies. It was determined that he carried a de novo duplication of the long arm of chromosome 7 [46,XY,dup(7)(q22.1-q31.1)]. Further molecular analysis revealed that the duplication was inverted. The distal chromosomal breakpoint occurred between the two genetic markers D7S515 and D7S522, which define a region previously shown to be disrupted in a familiar case of GTS. Yeast and bacterial artificial chromosome clones spanning the breakpoints were identified by means of FISH analysis. To further characterize the distal breakpoint for a role in GTS, we performed Southern blot hybridization analysis and identified a 6.5-kb SacI junction fragment in the patient's genomic DNA. The DNA sequence of this fragment revealed two different breaks in 7q31 within a region of approximately 500 kb. IMMP2L, a novel gene coding for the apparent human homologue of the yeast mitochondrial inner membrane peptidase subunit 2, was found to be disrupted by both the breakpoint in the duplicated fragment and the insertion site in 7q31. The cDNA of the human IMMP2L gene was cloned, and analysis of the complete 1,522-bp transcript revealed that it encompassed six exons spanning 860 kb. The possible role of IMMP2L and several other candidate genes within the region of chromosomal rearrangement, including NRCAM, Leu-Rch Rep, and Reelin, is discussed. The 7q31 breakpoint interval has also been implicated in other neuropsychiatric diseases that demonstrate some clinical overlap with GTS, including autism and speech-language disorder.

The incidence and significance of hemostatic abnormalities in patients with head injuries

Abnormal coagulation and fibrinolysis is a frequent complication in patients with head injury. This complication can be severe enough to lead to hemorrhage or thrombosis. A study was undertaken to determine if the hemostatic abnormalities are reliable indicators of outcome. Hemostasis in 269 patients with head injuries alone was screened using platelet count (PC), prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin clotting time (TCT), fibrinogen assay (FIB), level of fibrin-fibrinogen degradation products (FDP), and disseminated intravascular coagulation (DIC) score in the first 24 hours after injury. Test results were compared with the outcome (discharged or dead) in the entire group and in subgroups divided on the basis of the severity of injury as determined by the Glasgow coma score (GCS). Increased consumptive coagulopathy at admission, as reflected in the DIC score, predicts the outcome of head-injured patients with a high degree of accuracy. The degree of increase of the initial FDP level and prolongation of TCT also correlated positively with the outcome. Prolongation of the APTT correlated strongly with unfavorable outcome in a large group of patients, and in a small group, markedly accelerated APTT also predicted death. Stepwise logistic regression analysis demonstrated that GCS, FDP level, and DIC score predicted outcome. Other tests did not provide additional predictive value. Abnormal hemostasis frequently complicates the course of patients with head injuries. This study demonstrates that hemostasis tests are predictors of outcome in these patients.

Recurrent genetic aberrations in thymoma and thymic carcinoma

Apart from single reported aberrant karyotypes, genetic alterations in thymic epithelial neoplasms have not been investigated so far. In this study, 12 World Health Organization classification type A thymomas (medullary thymomas), 16 type B3 thymomas (well-differentiated thymic carcinomas), and nine type C thymomas, all of them primary thymic squamous cell carcinomas, were analyzed by comparative genomic hybridization and fluorescence in situ hybridization. With the exception of one single case, type A thymomas did not reveal chromosomal gains or losses in comparative genomic hybridization. In contrast, all type B3 thymomas showed chromosomal imbalances, with gain of 1q, loss of chromosome 6, and loss of 13q occurring in 11 (69%), six (38%), and five (31%) of 16 cases, respectively. In primary thymic squamous cell carcinoma, the most frequent chromosomal losses were observed for 16q (six of nine cases, 67%), 6 (4 of 9, 44%), and 3p and 17p (three of nine each, 33%), whereas recurrent gains of chromosomal material were gains of 1q (5 of 9, 56%), 17q, and 18 (three of nine each, 33%). This study shows that the distinct histological thymoma types A and B3 exhibit distinct genetic phenotypes, whereas type B3 thymoma and primary thymic squamous cell carcinoma partially share genetic aberrations. In addition to the possible tumorigenic role, the deletion in type B3 thymoma of chromosome 6, harboring the HLA locus, might play a role in the pathogenesis of paraneoplastic autoimmunity characteristic of thymoma.

Simultaneous production of interleukin 2, interleukin 4 and interferon-gamma by activated human blood lymphocytes

The production of interleukin 2 (IL 2), IL 4 and interferon-gamma (IFN-gamma) by in vitro activated unselected human blood mononuclear cells was studied at a single-cell level. Individual lymphokine-synthesizing cells were identified by intracellular immunofluorescent staining using cytokine-specific monoclonal or polyclonal antibodies. Cultures from adult blood donors revealed a biphasic kinetic production pattern for IL 2 and IFN-gamma with peaks occurring 4-6 and 24-30 h after initiation of the cultures. Approximately 20%-40% of the lymphocytes produced IL 2 and IFN-gamma. In contrast, only 1%-3% of the lymphocytes synthesized IL 4 with maximal frequency after 6 h of culture. CD4+ as well as CD8+ T cells contributed to the synthesis of all three lymphokines studied. CD4+CD45R- T cells were the major producers of IL 2 and IL 4, while CD8+CD45R- T cells were the most common phenotype of IFN-gamma-synthesizing cells. By performing two-color immunofluorescence studies we observed that among IL 4-producing cells every second one made simultaneously IL 2 and every fourth one made IFN-gamma. Mononuclear cells from umbilical cord blood could be stimulated to make IL 2 to the same extent as cells from adult blood donors. No IL 4 production and a strikingly reduced frequency of IFN-gamma producers were noted in cell cultures from neonates. IL 2, IL 4 and IFN-gamma accumulated in the Golgi system, which resulted in a characteristic morphology of the staining, eliminating problems with evaluation of background signals.

Adaptive optical networks using photorefractive crystals

The capabilities of photorefractive crystals as media for holographic interconnections in neural networks are examined. Limitations on the density of interconnections and the number of holographic associations which can be stored in photorefractive crystals are derived. Optical architectures for implementing various neural schemes are described. Experimental results are presented for one of these architectures.

Protein mapping by two-dimensional high performance liquid chromatography

Current developments in drug discovery in the pharmaceutical industry require highly efficient analytical systems for protein mapping providing high resolution, robustness, sensitivity, reproducibility and a high throughput of samples. The potential of two-dimensional (2D) HPLC as a complementary method to 2D-gel electrophoresis is investigated, especially in view of speed and repeatability. The method will be applied for proteins of a molecular mass <20 000 which are not well resolved in 2D-gel electrophoresis. The 2D-HPLC system described in this work consisted of anion- or cation-exchange chromatography in the first dimension and reversed-phase chromatography in the second dimension. We used a comprehensive two-dimensional approach based on different separation speeds. In the first dimension 2.5 microm polymeric beads bonded with diethylaminoethyl and sulfonic acid groups, respectively, were applied as ion exchangers and operated at a flow-rate of 1 ml/min. To achieve very high-speed and high-resolution separations in the second dimension, short columns of 14 x 4.6 mm I.D. with 1.5 microm n-octadecyl bonded, non-porous silica packings were chosen and operated at a flow-rate of 2.5 ml/min. Two reversed-phase columns were used in parallel in the second dimension. The analyte fractions from the ion-exchange column were transferred alternatively to one of the two reversed-phase columns using a 10-port switching valve. The analytes were deposited in an on-column focusing mode on top of one column while the analytes on the second column were eluted. Proteins, which were not completely resolved in the first dimension can, in most cases, be baseline-separated in the second dimension. The total value of peak capacity was calculated to 600. Fully unattended overnight runs for repeatability studies proved the applicability of the system. The values for the relative standard deviation (RSD) of the retention times of proteins were less than 1% (n = 15), while the RSDs of the peak areas were less than 15% (n = 15) on average. The limit of detection was 300 ng of protein on average and decreased to 50 ng for ovalbumin. The 2D-HPLC system offered high-resolution protein separations with a total analysis time of less than 20 min, equivalent to the run time of the first dimension.

Inhibition of anti-inflammatory drugs of prostaglandin production in cultured macrophages

1. A sensitive, simple, reproducible, and economical assay for structure-activity investigations of non-steroidal anti-inflammatory drugs (NSAID) is lacking. This has prompted us to investigate the advantages and limitations of defining for that purpose the potency of NSAID's as inhibitors of tumour promoter-induced prostaglandin (PG) release from mouse peritoneal macrophages in culture. 2. These cells release mainly PGE2 and PGI2 (measured as its stable hydrolysis product 6-keto-PGF1 alpha) upon stimulation with the tumour promoter 12-O-tetradecanoylphorbol-13-acetate (TPA). 3. The PG release was dose-dependently inhibited by a variety of NSAID's. Their inhibitory potency was dependent on the culture conditions employed. The widely used acidic NSAID's were more potent when assayed under serum free culture conditions at low pH. 4. Dose response curves for acidic NSAID tested under serum free conditions allowed for the definition of IC50 values being reproducible within their 95% confidence limits. 5. The IC50 values obtained for different standard acidic NSAID's varied within 4 orders of magnitude. They corresponded favourably to their clinical potency and their potency in a variety of standard tests for anti-inflammatory drugs. 6. IC50 values of five congeners of indomethacin differed up to 2 orders of magnitude in agreement with in vivo observations indicating the applicability of this assay for structure-activity investigations.

Epigenetic alteration at the DLK1-GTL2 imprinted domain in human neoplasia: analysis of neuroblastoma, phaeochromocytoma and Wilms' tumour

Epigenetic alterations in the 11p15.5 imprinted gene cluster are frequent in human cancers and are associated with disordered imprinting of insulin-like growth factor (IGF)2 and H19. Recently, an imprinted gene cluster at 14q32 has been defined and includes two closely linked but reciprocally imprinted genes, DLK1 and GTL2, that have similarities to IGF2 and H19, respectively. Both GTL2 and H19 are maternally expressed RNAs with no protein product and display paternal allele promoter region methylation, and DLK1 and IGF2 are both paternally expressed. To determine whether methylation alterations within the 14q32 imprinted domain occur in human tumorigenesis, we investigated the status of the GTL2 promoter differentially methylated region (DMR) in 20 neuroblastoma tumours, 20 phaeochromocytomas and, 40 Wilms' tumours. Hypermethylation of the GTL2 promoter DMR was detected in 25% of neuroblastomas, 10% of phaeochromocytoma and 2.5% of Wilms' tumours. Tumours with GTL2 promoter DMR hypermethylation also demonstrated hypermethylation at an upstream intergenic DMR thought to represent a germline imprinting control element. Analysis of neuroblastoma cell lines revealed that GTL2 DMR hypermethylation was associated with transcriptional repression of GTL2. These epigenetic findings are similar to those reported in Wilms' tumours in which H19 repression and DMR hypermethylation is associated with loss of imprinting (LOI, biallelic expression) of IGF2. However, a neuroblastoma cell line with hypermethylation of the GTL2 promoter and intergenic DMR did not show LOI of DLK1 and although treatment with a demethylating agent restored GTL2 expression and reduced DLK1 expression. As described for IGF2/H19, epigenetic changes at DLK1/GTL2 occur in human cancers. However, these changes are not associated with DLK1 LOI highlighting differences in the imprinting control mechanisms operating in the IGF2-H19 and DLK1-GTL2 domains. GTL2 promoter and intergenic DMR hypermethylation is associated with the loss of GTL2 expression and this may contribute to tumorigenesis in a subset of human cancers.

Sequential changes of biochemical bone parameters after kidney transplantation

BACKGROUND

Persistent hyperparathyroidism after renal transplantation (Rtx) has been reported in several studies. However these studies evaluated biochemical bone parameters either only during a short time period (up to 6 months) or for a longer time period, but with long intervals in between. Therefore, we prospectively evaluated biochemical bone parameters of kidney-transplant recipients at short intervals for 2 years after surgery.

METHODS

Biochemical bone parameters were prospectively investigated in 129 patients 2, 3, 5, 8, 12, 18 and 24 months after Rtx. All patients received prednisone and cyclosporin A as immunosuppressive therapy, and 75 patients also received azathioprine. None of the patients was treated with calcium, phosphorus, or vitamin D preparations.

RESULTS

Serum creatinine levels decreased from 166.8 +/- 5.4 mumol/l to 140.0 +/- 4.9 two years after Rtx; (data are expressed as mean +/- s.e.m.). Serum phosphorus levels increased slightly from 0.9 +/- 0.022 mmol/l to 0.98 +/- 0.025 (12 m), but remained within the lower normal range. We observed a rise in total and albumin adjusted calcium concentrations 3 months after Rtx. 52% of all patients had serum calcium levels above 2.62 mmol/l (upper normal limit in our laboratory) 3 months after renal transplantation with a gradual decrease thereafter. There was no correlation of calcium and PTH levels. We observed a significant rise in biochemical bone parameters from 2 to 5 months after renal transplantation (P < 0.001): alkaline phosphatase (AP) increased from 164.3 +/- 9.4 to 236 +/- 12.7 U/l (normal 50-180), bone specific alkaline phosphatase (BAP) rose from 17.7 +/- 1.36 to 23.2 +/- 1.7 ng/ml (normal:4-20) and osteocalcin (OC) increased from 20.2 +/- 1.5 to 26.7 +/- 1.9 ng/ml (normal 4-12). AP and BAP levels values normalized 12 months after renal transplantation, whereas OC was still above normal throughout the study period. Patients were subdivided into two groups: those with good and those with impaired graft functions. Patients with good graft function had stable serum creatinine levels (< or = 132 mumol/l or < or = 1.5 mg/dl) well below the mean serum creatinine concentration during the study period. The significant changes in AP, BAP, and OC occurred irrespective of renal function. However, patients with impaired graft function (n = 65) had significantly higher PTH-levels (70 pg/ml higher) than patients with good graft function (n = 64), P < 0.01. PTH was positively correlated with serum creatinine (r = 0.81, P < 0.001). Moreover, patients with low 25 (OH) vitamin D levels (n = 63) had significantly higher PTH concentrations (between 40 and 80 pg/ml, P < 0.01) throughout the study period compared to patients (n = 66) with a sufficient 25(OH)D supply irrespective of graft function. There was a negative correlation of 25 (OH)D levels and PTH; (r = -0.49, P < 0.001). 1,25(OH)2D3 (evaluated in 24 patients) levels increased from 46.5 +/- 6.6 to 76.9 +/- 7.6 pg/ml (normal:35-90) at 12 months.

CONCLUSION

Hypercalcaemia is a common phenomenon in the early period after kidney transplantation and occurs in the presence of low normal phosphorus levels. It is most probably related to improved PTH action and 1-hydroxylation of vitamin D. The rise in biochemical bone parameters between 3 and 5 months occurs irrespective of graft function and normalization is only achieved 1 year after transplantation. PTH is constantly elevated for up to 2 years after kidney transplantation and is most probably related (a) to impaired graft function and (b) to suboptimal 25 OH vitamin D supply.

A stress-induced early innate response causes multidrug tolerance in melanoma

Acquired drug resistance constitutes a major challenge for effective cancer therapies with melanoma being no exception. The dynamics leading to permanent resistance are poorly understood but are important to design better treatments. Here we show that drug exposure, hypoxia or nutrient starvation leads to an early innate cell response in melanoma cells resulting in multidrug resistance, termed induced drug-tolerant cells (IDTCs). Transition into the IDTC state seems to be an inherent stress reaction for survival toward unfavorable environmental conditions or drug exposure. The response comprises chromatin remodeling, activation of signaling cascades and markers implicated in cancer stemness with higher angiogenic potential and tumorigenicity. These changes are characterized by a common increase in CD271 expression concomitantly with loss of differentiation markers such as melan-A and tyrosinase, enhanced aldehyde dehydrogenase (ALDH) activity and upregulation of histone demethylases. Accordingly, IDTCs show a loss of H3K4me3, H3K27me3 and gain of H3K9me3 suggesting activation and repression of differential genes. Drug holidays at the IDTC state allow for reversion into parental cells re-sensitizing them to the drug they were primarily exposed to. However, upon continuous drug exposure IDTCs eventually transform into permanent and irreversible drug-resistant cells. Knockdown of CD271 or KDM5B decreases transition into the IDTC state substantially but does not prevent it. Targeting IDTCs would be crucial for sustainable disease management and prevention of acquired drug resistance.

Productivity, Machinery and Skills in a Sample of British and German Manufacturing Plants

On the basis of interviews with management and factory floor employees at 45 matched firms in Britain and West Germany, this article examines the roles of machinery and workforce skills in explaining comparative produc tivity performance. The average age of British machinery was not very different from that found in German plants, but it was less technically advanced, was subject to more frequent breakdowns and breakdowns took longer to correct. Productivity was higher in Germany in each of our matched product groups and the importance of skills at all levels was apparent.

GARP: a key receptor controlling FOXP3 in human regulatory T cells

Recent evidence suggests that regulatory pathways might control sustained high levels of FOXP3 in regulatory CD4(+)CD25(hi) T (T(reg)) cells. Based on transcriptional profiling of ex vivo activated T(reg) and helper CD4(+)CD25(-) T (T(h)) cells we have identified GARP (glycoprotein-A repetitions predominant), LGALS3 (lectin, galactoside-binding, soluble, 3) and LGMN (legumain) as novel genes implicated in human T(reg) cell function, which are induced upon T-cell receptor stimulation. Retroviral overexpression of GARP in antigen-specific T(h) cells leads to an efficient and stable re-programming of an effector T cell towards a regulatory T cell, which involves up-regulation of FOXP3, LGALS3, LGMN and other T(reg)-associated markers. In contrast, overexpression of LGALS3 and LGMN enhance FOXP3 and GARP expression, but only partially induced a regulatory phenotype. Lentiviral down-regulation of GARP in T(reg) cells significantly impaired the suppressor function and was associated with down-regulation of FOXP3. Moreover, down-regulation of FOXP3 resulted in similar phenotypic changes and down-regulation of GARP. This provides compelling evidence for a GARP-FOXP3 positive feedback loop and provides a rational molecular basis for the known difference between natural and transforming growth factor-beta induced T(reg) cells as we show here that the latter do not up-regulate GARP. In summary, we have identified GARP as a key receptor controlling FOXP3 in T(reg) cells following T-cell activation in a positive feedback loop assisted by LGALS3 and LGMN, which represents a promising new system for the therapeutic manipulation of T cells in human disease.