The effect of body mass index on therapeutic response to bacterial vaginosis in pregnancy.

Am J Perinatol. 2008 Apr;25(4):233-7

Authors: Mastrobattista JM, Klebanoff MA, Carey JC, Hauth JC, Macpherson CA, Ernest J, Cotroneo M, Leveno KJ, Wapner R, Varner M, Iams JD, Moawad A, Sibai BM, Miodovnik M, Dombrowski M, O'Sullivan MJ, Vandorsten JP, Langer O

Our objective was to determine the effect of body mass index (BMI) on response to bacterial vaginosis (BV) treatment. A secondary analysis was conducted of two multicenter trials of therapy for BV and TRICHOMONAS VAGINALIS. Gravida were screened for BV between 8 and 22 weeks and randomized between 16 and 23 weeks to metronidazole or placebo. Of 1497 gravida with asymptomatic BV and preconceptional BMI, 738 were randomized to metronidazole; BMI was divided into categories: < 25, 25 to 29.9, and >/= 30. Rates of BV persistence at follow-up were compared using the Mantel-Haenszel chi square. Multiple logistic regression was used to evaluate the effect of BMI on BV persistence at follow-up, adjusting for potential confounders. No association was identified between BMI and BV rate at follow-up ( P = 0.21). BMI was associated with maternal age, smoking, marital status, and black race. Compared with women with BMI of < 25, adjusted odds ratio (OR) of BV at follow-up were BMI 25 to 29.9: OR, 0.66, 95% CI 0.43 to 1.02; BMI >/= 30: OR, 0.83, 95% CI 0.54 to 1.26. We concluded that the persistence of BV after treatment was not related to BMI. PMID: 18548397 [PubMed - in process]

Lipid raft-dependent uptake, signaling, and intracellular fate of Porphyromonas gingivalis in mouse macrophages.

Cell Microbiol. 2008 Jun 10;

Authors: Wang M, Hajishengallis G

Lipid rafts are cholesterol-enriched microdomains involved in cellular trafficking and implicated as portals for certain pathogens. We sought to determine whether the oral pathogen Porphyromonas gingivalis enters macrophages via lipid rafts, and if so, to examine the impact of raft entry on its intracellular fate. Using J774A.1 mouse macrophages, we found that P. gingivalis colocalizes with lipid rafts in a cholesterol-dependent way. Depletion of cellular cholesterol using methyl-beta-cyclodextrin resulted in about 50% inhibition of P. gingivalis uptake, although this effect was reversed by cholesterol reconstitution. The intracellular survival of P. gingivalis was dramatically inhibited in cholesterol-depleted cells relative to untreated or cholesterol-reconstituted cells, even when infections were adjusted to allow equilibration of the initial intracellular bacterial load. P. gingivalis thus appeared to exploit raft-mediated uptake for promoting its survival. Consistent with this, lipid raft disruption enhanced the colocalization of internalized P. gingivalis with lysosomes. In contrast, raft disruption did not affect the expression of host receptors interacting with P. gingivalis, although it significantly inhibited signal transduction. In summary, P. gingivalis uses macrophage lipid rafts as signaling and entry platforms, which determine its intracellular fate to the pathogen's own advantage. PMID: 18547335 [PubMed - as supplied by publisher]

J Microbiol. 2008 Apr;46(2):174-82

Authors: Lee JW, Nam JH, Kim YH, Lee KH, Lee DH

Succession of bacterial communities during the first 36 h of biofilm formation in coastal water was investigated at 3 approximately 15 h intervals. Three kinds of surfaces (i.e., acryl, glass, and steel substratum) were submerged in situ at Sacheon harbor, Korea. Biofilms were harvested by scraping the surfaces, and the compositions of bacterial communities were analyzed by terminal restriction fragment length polymorphism (T-RFLP), and cloning and sequencing of 16S rRNA genes. While community structure based on T-RFLP analysis showed slight differences by substratum, dramatic changes were commonly observed for all substrata between 9 and 24 h. Identification of major populations by 16S rRNA gene sequences indicated that gamma-Proteobacteria (Pseudomonas, Acinetobacter, Alteromonas, and uncultured gamma-Proteobacteria) were predominant in the community during 0 approximately 9 h, while the ratio of alpha-Proteobacteria (Loktanella, Methylobacterium, Pelagibacter, and uncultured alpha-Proteobacteria) increased 2.6 approximately 4.8 folds during 24 approximately 36 h of the biofilm formation, emerging as the most predominant group. Previously, alpha-Proteobacteria were recognized as the pioneering organisms in marine biofilm formation. However, results of this study, which revealed the bacterial succession with finer temporal resolution, indicated some species of gamma-Proteobacteria were more important as the pioneering population. Measures to control pioneering activities of these species can be useful in prevention of marine biofilm formation. PMID: 18545967 [PubMed - in process]

High throughput production of recombinant human proteins for crystallography.

Methods Mol Biol. 2008;426:221-46

Authors: Gileadi O, Burgess-Brown NA, Colebrook SM, Berridge G, Savitsky P, Smee CE, Loppnau P, Johansson C, Salah E, Pantic NH

This chapter presents in detail the process used in high throughput bacterial production of recombinant human proteins for crystal structure determination. The core principles are: (1) Generating at least 10 truncated constructs from each target gene. (2) Ligation-independent cloning (LIC) into a bacterial expression vector. All proteins are expressed with an N-terminal, TEV protease cleavable fusion peptide. (3) Small-scale test expression to identify constructs producing soluble protein. (4) Liter-scale production in shaker flasks. (5) Purification by Ni-affinity chromatography and gel filtration. (6) Protein characterization and preparation for crystallography. The chapter also briefly presents alternative procedures, to be applied based on specific knowledge of protein families or when the core protocol is unsatisfactory. This scheme has been applied to more than 550 human proteins (>10,000 constructs) and has resulted in the deposition of 112 unique structures. The methods presented do not depend on specialized equipment or robotics; hence, they provide an effective approach for handling individual proteins in a regular research lab. PMID: 18542867 [PubMed - in process]