Genetic susceptibility to invasive meningococcal disease: MBL2 structural polymorphisms revisited in a large case-control study and a systematic review.

AbstractInvasive infection caused by Neisseria meningitidis is a worldwide public health problem. Previous reports have indicated that carriage of common 'defective' structural polymorphisms of the host mannose-binding lectin gene (MBL2) greatly increases an individual's risk of developing the disease. We report the largest case-control study so far to investigate the effect of these polymorphisms in meningococcal disease (296 PCR-positive cases and 5196 population controls, all of European ancestry) and demonstrate that no change in risk is associated with the polymorphisms overall or in any age-defined subgroup. This finding contrasts with two smaller studies that reported an increase in risk. A systematic review of all studies of MBL2 polymorphisms in people of European ancestry published since 1999, including 24 693 individuals, revealed a population frequency of the combined 'defective'MBL2 allele of 0.230 (95% confidence limits: 0.226-0.234). The past reported associations of increased risk of meningococcal disease were because of low 'defective' allele frequencies in their study control populations (0.13 and 0.04) that indicate systematic problems with the studies. The data from our study and all other available evidence indicate that MBL2 structural polymorphisms do not predispose children or adults to invasive meningococcal disease.

Local delivery of chlorhexidine using a tooth-bonded delivery system

Films containing 20% w/w chlorhexidine base (particle size 63-125 mu m) in poly(epsilon-caprolactone), MW 35 000-45 000, were prepared by solvent evaporation and sections attached to the mesio-lingual and mesio-buccal surfaces of the lower first molar in healthy volunteers. Saliva (

Polycrystalline silicon film growth in a SiF4/SiH4/H2 plasma

The growth of polycrystalline silicon (polysilicon) films from SiF4/SiH4/H2 gas mixtures is reported. The polysilicon films have been deposited in a multi process reactor by a PECVD process. The effect of r.f. power, chamber temperature and gas flow ratios on grain size and deposition rate have been determined. The fluorine concentration and the grain sizes of the films have been determined by SIMS and atomic force microscopy (AFM), respectively. Grain sizes in excess of 900 A are reported for layers deposited at 300°C. © 1999 Published by Elsevier Science S.A. All rights reserved.

Incidence of glaucoma in patients with uveitis

Purpose: To evaluate the incidence of glaucoma and elevation of intraocular pressure (IOP) in patients with inflammatory eye disease. Methods: Retrospective review of medical records of 391 consecutive patients with uveitis attending a uveitis clinic of an academic Department of Ophthalmology from January 1999 to August 2002. Demographic, ocular and systemic variables were recorded. The diagnosis and treatment of uveitis were recorded. Uveitis was classified according to standard anatomic, etiological and clinical criteria. "Glaucoma" was defined as elevated IOP (>21 mm Hg) or glaucomatous optic nerve damage requiring medical and/or surgical anti-glaucoma treatment. Kaplan-Maier analysis and log-rank tests were used to evaluate and compare the incidence of glaucoma. Results: The incidence of glaucoma as defined above at 3 and 12 months after acute uveitis was 7.6%. In patients with chronic uveitis (n = 337), the incidence of glaucoma at 1 and 5 years was 6.5% and 11.1%, respectively. There was no statistically significant difference in the incidence of glaucoma between different types of uveitis, idiopathic versus non-idiopathic, and among anterior, intermediate, posterior and panuveitis. Visual loss occurred more frequently in patients with glaucoma than in patients without glaucoma. Conclusion: In patients with chronic inflammatory eye disease, the presence of glaucoma was associated with an increasing risk of visual loss. The incidence of glaucoma increased with time and was similar among the different types of uveitis.

Detection of avian influenza virus by fluorescent DNA barcode-based immunoassay with sensitivity comparable to PCR

In this paper, a coupling of fluorophore-DNA barcode and bead-based immunoassay for detecting avian influenza virus (AIV) with PCR-like sensitivity is reported. The assay is based on the use of sandwich immunoassay and fluorophore-tagged oligonucleotides as representative barcodes. The detection involves the sandwiching of the target AIV between magnetic immunoprobes and barcode-carrying immunoprobes. Because each barcode-carrying immunoprobe is functionalized with a multitude of fluorophore-DNA barcode strands, many DNA barcodes are released for each positive binding event resulting in amplification of the signal. Using an inactivated H16N3 AIV as a model, a linear response over five orders of magnitude was obtained, and the sensitivity of the detection was comparable to conventional RT-PCR. Moreover, the entire detection required less than 2 hr. The results indicate that the method has great potential as an alternative for surveillance of epidemic outbreaks caused by AIV, other viruses and microorganisms.

A light microscopic and autoradiographic study of non-irradiated and irradiated ocular wounds

Focal gamma irradiation was used to limit the intraocular extension of scar tissue which typically occurs after posterior perforating injury to the eye. Standard posterior perforating injuries were created in the right eye of forty-eight rabbits, half of which had the site of perforation focally irradiated using a Cobalt 60 ophthalmic plaque. Non-irradiated wounds healed with profuse formation of highly cellular and vascularised granulation tissue which invaded the vitreous to form contractile vitreo-retinal membranes. In irradiated eyes vitreo-retinal membrane formation was infrequent; the wounds showing only sparse granulation tissue with little or no extension into the vitreous cavity. Autoradiographic studies carried out in a second group of 40 animals showed that the episclera was the main source of the proliferating fibroblasts, and cell counts confirmed that the inflammatory and repair responses in irradiated wounds were both delayed and attenuated.

Genetic variation in the 6p22.3 gene DTNBP1, the human ortholog of the mouse dysbindin gene, is associated with schizophrenia

Prior evidence has supported the existence of multiple susceptibility genes for schizophrenia. Multipoint linkage analysis of the 270 Irish high-density pedigrees that we have studied, as well as results from several other samples, suggest that at least one such gene is located in region 6p24-21. In the present study, family-based association analysis of 36 simple sequence-length-polymorphism markers and of 17 SNP markers implicated two regions, separated by approximately 7 Mb. The first region, and the focus of this report, is 6p22.3. In this region, single-nucleotide polymorphisms within the 140-kb gene DTNBP1 (dystrobrevin-binding protein 1, or dysbindin) are strongly associated with schizophrenia. Uncorrected, empirical P values produced by the program TRANSMIT were significant (P