Repeat sizes at CAG/CTG loci CTG18.1, ERDA1 and TGC13-7a in schizophrenia

A number of studies using the repeat expansion detection (RED) technique have suggested an association between unknown large CAG/CTG repeats and schizophrenia. The polymorphic CAG/CTG repeat loci CTG18.1 and ERDA1 have been reported to account for a high proportion (approximately 90%) of the large repeats detected by RED and may therefore be responsible for the cited association. The recently described locus TGC13-7a contains a highly polymorphic CTA/TAG and CAG/CTG composite repeat, and is thus another authentic candidate. In the present investigation, each locus was analysed for association with schizophrenia in a sample of 206 patients and 219 group-matched controls. No evidence for association of CTG18.1, ERDA1 and/or TGC13-7a with schizophrenia was found. The combined data accounted for only 54% of the CAG/CTG arrays of > 40 repeats found in our previous RED analysis.     

Clinical,hematologic, and immunologic effects of interleukin-10 in humans

We conducted a double-blind, placebo-controlled study to investigate the safety, pharmacokinetics, and immunological properties of interleukin-10 (IL-10) administration in healthy humans. Volunteers received a single intravenous bolus injection of recombinant human IL-10 (1, 10, or 25g/kg) or placebo. Cytokine production in whole blood and peripheral blood mononuclear cells (PBMC) was assessed before and 3, 6, 24, and 48 hr after the injection. Peak serum concentrations of IL-10 (15±1.1, 208±20.1, and 505±22.3 ng/ml) occurred after 2–5 min for 1, 10, and 25g/kg IL-10, respectively. The terminal-phase half-life was 3.18 hr. A transient leukocytosis (24–63% above baseline) was observed 6 hr after injection, which coincided with a dose-dependent decrease (12–24%) in neutrophil superoxide generation. There was a marked inhibition (60–95%) of endotoxin-induced IL-6 production from whole blood in each group receiving IL-10. Production of IL-8 in endotoxin-stimulated blood was reduced in the 10g/kg group. In PBMC stimulated with phytohemagglutinin and phorbol ester, there was a decrease (72–87%) in interferon- (IFN) production 6 hr after IL-10 with a return to pre-IL-10 levels after 24 hr. This reduction was only partially associated with a decrease in the number of CD2-bearing cells. We conclude that IL-10 administration into humans is without significant side effects, and a single injection reducesex vivo production of IL-6, IL-8, and IFN.     

Automated Recognition of Lateral from PA Chest Radiographs: Saving Seconds in a PACS Environment

Images acquired in a two-view digital chest examination are frequently not electronically distinguishable. As a result the lateral and posterioanterio (PA) images are often improperly positioned on a PACS work station. A series of 1998 chest radiographs (999 lateral, 999 PA or AP) were used to develop a neural network classifier. The images were down-sampled to 16 × 16 matrices, and a feed-forward neural network was trained and tested using the leave-one-out method. Using five nodes in the hidden layer, the neural network correctly identified 987 of the 999 test cases (98.8%) (average of six runs). The simple architecture and speed of this technique suggests that it would be a useful addition to PACS work station software. The accumulated time saved by correctly positioning the lateral and PA chest images on the work station monitors in accordance with each radiologists hanging protocols was estimated to be about 1 week of radiologist time per year.     

Randomized controlled trial assessing the effect of vitamin A supplementation on maternal morbidity during pregnancy and postpartum among HIV-infected women

OBJECTIVE: To determine whether low-cost treatment of HIV using vitamin A would be beneficial, we examined the effect of vitamin A supplementation on morbidity of HIV-1 infected women. METHODS: We conducted a randomized, double blind placebo-controlled trial at King Edward VIII Hospital, in Durban, South Africa. In total, 312 HIV-seropositive pregnant women between 28 and 32 weeks' gestation were recruited into this trial. Patients were randomized to receive placebo or 5,000 IU retinyl palmitate and 30 mg beta-carotene daily. At delivery of their children, patients received placebo or 200,000 IU retinyl palmitate. The main outcome measures were pre- and postnatal report of HIV-related symptoms. RESULTS: Vitamin A did not confer any significant beneficial effect on the report of either HIV or pregnancy-related symptoms during the pre- or postnatal period. CONCLUSION: In this study of HIV-infected pregnant women, vitamin A supplementation given in doses designed to decrease mother-to-infant transmission did not result in significant beneficial effect on reported symptoms pre- or postnatally. Further investigation with larger number of participants, tailoring supplementation for specific clinical conditions, outside the context of pregnancy, is required to help clarify the possible clinical benefits of vitamin A.     

Cost comparison of genetic and clinical screening in families with hereditary hemorrhagic telangiectasia

Endoglin (ENG) and ALK-1 mutations cause hereditary hemorrhagic telangiecstasia (HHT), an autosomal dominant disorder leading to vascular dysplasia in the form of mucocutaneous telangiectasia and visceral arteriovenous malformations (AVMs). We proposed to compare two alternative strategies for management of HHT: screening HHT families with molecular diagnostic tests followed by targeted clinical screening versus conventional clinical screening. A decision analytic model was constructed to compare screening strategies for a hypothetical HHT family. The family consists of 1 index case and 13 relatives. The clinical screening protocol in use at the Canadian HHT Center in Toronto was assumed to be the standard of care. Unit costs for clinical screening (in Canadian dollars) were obtained from the 2003 Ontario Health Insurance Schedule of Benefits. Genetic screening costs were estimated for quantitative multiplex PCR and sequencing of Endoglin (ENG) and ALK-1 genes, as performed at HHT Solutions, Toronto. The genetic screening strategy resulted in a net cost of $4,060 per individual versus $5,975 for the clinical screening strategy. The genetic screening strategy would save $1,915 per family member or $26,810 saved per family. Sensitivity analyses revealed that the genetic screening strategy was cost saving over all plausible ranges of input variables for all hypothetical families tested. We concluded that a genetic screening strategy with targeted clinical screening is more economically attractive than conventional clinical screening and results in a reduction in the number of clinical tests for family members who do not have HHT.     

The effects of meiosis activating sterol on in-vitro maturation and fertilization of human oocytes from stimulated and unstimulated ovaries

The object of this study was to assess functional maturation in vitro by obtaining data on the fertilization and embryonic competence of human oocytes with or without exposure to meiosis activating sterol (MAS) during maturation in vitro. Immature oocytes were either collected from unstimulated patients with polycystic ovaries (PCO) during gynaecological surgery, or were donated by patients undergoing a cycle of intracytoplasmic sperm injection (ICSI) treatment including ovarian stimulation with gonadotrophins. PCO oocytes had variable cumulus cover, which was retained during culture while those from ICSI patients were cultured without cumulus. The study included 119 oocytes from PCO patients and 72 from ICSI patients. The oocytes were allowed to mature in vitro for up to 46 h in the presence or absence of MAS. Mature oocytes were inseminated by ICSI with fertile donor spermatozoa and embryo development was monitored in vitro. MAS (30 microg/ml) significantly increased the survival of oocytes from PCO patients (P < 0.01) but did not significantly affect the proportion completing maturation in vitro. For the ICSI patients, >90% of oocytes survived in all culture groups, regardless of MAS addition, however MAS (10 or 30 microg/ml) significantly increased the proportion of oocytes maturing in vitro (P < 0.05). The apparent tendency towards improved subsequent development in vitro will require larger numbers of oocytes for evaluation. Oocytes from ICSI patients matured more rapidly in vitro than those from PCO patients. Our results show positive effects of MAS on human oocytes, confirming previous data in mice. This work may have implications for the future clinical application of IVM.     

HBME-1 and antithrombomodulin in the differential diagnosis of malignant mesothelioma of pleura.

AIMS: To determine the usefulness of antibodies HBME-1 and antithrombomodulin in the differential diagnosis of malignant mesothelioma of the pleura. METHODS: Using microwave antigen retrieval and streptavidin-biotin complex horseradish peroxidase immunohistochemistry the above antibodies were used to stain sections of 57 malignant mesotheliomas, 17 reactive pleural hyperplasias, 23 cases of carcinoma metastatic in pleura, 20 primary ovarian cell carcinomas, and 20 primary renal cell carcinomas. RESULTS: Eighty six per cent of mesotheliomas and 82% of reactive mesothelial hyperplasias stained strongly with HBME-1. However, 48% of carcinomas metastatic to pleura also stained, as did all serous ovarian carcinomas. Seventy two per cent of mesotheliomas and 24% of reactive mesothelial hyperplasias stained strongly with the antithrombomodulin antibody; 86% and 88%, respectively, of these cases showed staining of any type. While 26% of metastatic carcinomas showed some staining with antithrombomodulin, only one third of these (9%) showed strong, yet focal, staining. Of 40 ovarian and renal carcinomas only two (5%) showed any staining with antithrombomodulin. CONCLUSIONS: HBME-1, although a sensitive mesothelial marker, is not sufficiently specific to be useful diagnostically, as almost half of carcinomas metastatic to pleura also stained positive. Antithrombomodulin is also a sensitive mesothelial marker and is sufficiently specific to be a useful discriminator, positively identifying, in appropriate circumstances, the mesothelial nature of a cell population.     

Cloning and expression of the major secreted cathepsin B-like protein from juvenile Fasciola hepatica and analysis of immunogenicity following liver fluke infection

The functions of the cathepsin B-like proteases in liver flukes are unknown and analysis has been hindered by a lack of protein for study, since the protein is produced in small amounts by juvenile flukes. To circumvent this, we isolated and characterized a cDNA encoding the major secreted cathepsin B from Fasciola hepatica. The predicted preproprotein is 339 amino acids in length, with the mature protease predicted to be 254 amino acids long, and shows significant similarity to parasite and mammalian cathepsin B. Only one of the two conserved histidine residues required for cathepsin B exopeptidase activity is predicted to be present. Recombinant preproprotein was produced in yeast, and it was shown that the recombinant proprotein can undergo a degree of self-processing in vitro to the mature form, which is active against gelatin and synthetic peptide substrates. The recombinant protein is antigenic in vaccinated rats, and antibodies to the protein are detected early after infection of rats and sheep with F. hepatica. The kinetics of the response to cathepsin B and cathepsin L after infection of sheep and rats confirm the temporal expression of these proteins during the life cycle of the parasite.     

Altered lymphocyte recognition repertoire during ageing. III. Changes in MHC restriction patterns in parental T lymphocytes and diminution in T suppressor function.

Irradiated C57BL/6 and (C57BL/6 X C3H)F1 mice have been reconstituted with bone marrow prepared from young (2 month) or aged (24 month) C57BL/6 donors. Indirect examination of the T cell receptor for H-2d alloantigens on H-2b splenocytes of these reconstituted mice, using the suppression of the H-2b anti-H-2d response induced by (H-2b X H-2d)F1 anti-(H-2b anti-H-2d) suppressor cells, suggests that the allo-receptor repertoire derived from bone marrow of aged mice is different from that of T cells derived from young bone-marrow precursors. These observations were supported by direct evidence, from rosette formation with murine erythrocytes, for changes in the T cell receptor of these different (radiation-chimaera) sources of H-2b-T cells. Along with these subtle changes in the allo-receptor repertoire of T cells derived from bone marrow of aged mice grown in irradiated F1 hosts, there is a decrease (compared with mice reconstituted with bone marrow from young donors) in the apparent frequency of T cells recognizing antigen in association with the new MHC-restricting elements in these parent F1 chimaeras. Analysis of those cell subsets reported to be involved in the regulation of MLC responses suggests that some of the differences observed between T cell differentiation from bone-marrow stem cells of young or aged donors may in part be explained by a diminution in the production from bone marrow of aged mice of those cells important for homeostasis within the immune system.     

Detection of human immunodeficiency virus type 1 (HIV-1) DNA and RNA sequences in HIV-1 antibody-positive blood donors in Uganda by the Roche AMPLICOR assay.

The ability of commercially available PCR-based assays to accurately detect or quantitate human immunodeficiency virus type 1 (HIV-1) DNA or RNA in individuals predominantly infected with HIV-1 subtypes A and D is not known. Therefore, peripheral leukocytes from 43 individuals in Kampala, Uganda, positive for HIV by the Western blot (immunoblot) assay were tested by using the Roche AMPLICOR HIV-1 assay for the detection of DNA gag sequences. Plasma from these same individuals was tested by using the Roche HIV-1 AMPLICOR MONITOR HIV-1 assay for the quantitation of HIV-1 RNA gag sequences. In addition, peripheral leukocytes were tested for HIV-1 DNA by using a lower annealing temperature or a different primer pair for the HIV-1 pol region. The proportions of individuals with detectable HIV-1 DNA and RNA gag sequences by the Roche assays were 74 and 90%, respectively. The proportions positive for HIV-1 DNA sequences by using a 50 degrees C annealing temperature or the pol primer pair were 71 and 98%, respectively. In summary, the standard Roche assay did not detect HIV-1 DNA sequences in a significant number of HIV-1-infected individuals in Uganda. However, use of a pol primer pair increased the sensitivity of the assay to 98%. The sensitivity of the Roche AMPLICOR MONITOR assay for the detection and quantitation of HIV-1 RNA sequences was significantly higher than that of the DNA-based assay, but the efficiency of the assay, and hence, the accuracy of the values obtained with RNA, is not known. Modifications to existing assays are needed to enhance the sensitivities and accuracies of these commercially available assays for use in developing countries where non-B HIV-1 subtypes predominate.