The lactose operon from Lactobacillus casei is involved in the transport and metabolism of the human milk oligosaccharide core-2 N-acetyllactosamine

The lactose operon (lacTEGF) from Lactobacillus casei strain BL23 has been previously studied. The lacT gene codes for a transcriptional antiterminator, lacE and lacF for the lactose-specific phosphoenolpyruvate: phosphotransferase system (PTSLac) EIICB and EIIA domains, respectively, and lacG for the phospho-β-galactosidase. In this work, we have shown that L. casei is able to metabolize N-acetyllactosamine (LacNAc), a disaccharide present at human milk and intestinal mucosa. The mutant strains BL153 (lacE) and BL155 (lacF) were defective in LacNAc utilization, indicating that the EIICB and EIIA of the PTSLac are involved in the uptake of LacNAc in addition to lactose. Inactivation of lacG abolishes the growth of L. casei in both disaccharides and analysis of LacG activity showed a high selectivity toward phosphorylated compounds, suggesting that LacG is necessary for the hydrolysis of the intracellular phosphorylated lactose and LacNAc. L. casei (lacAB) strain deficient in galactose-6P isomerase showed a growth rate in lactose (0.0293 ± 0.0014 h-1) and in LacNAc (0.0307 ± 0.0009 h-1) significantly lower than the wild-type (0.1010 ± 0.0006 h-1 and 0.0522 ± 0.0005 h-1, respectively), indicating that their galactose moiety is catabolized through the tagatose-6P pathway. Transcriptional analysis showed induction levels of the lac genes ranged from 130 to 320-fold in LacNAc and from 100 to 200-fold in lactose, compared to cells growing in glucose

Treatment response in Kawasaki disease is associated with sialylation levels of endogenous but not therapeutic intravenous immunoglobulin G.

OBJECTIVES: Although intravenous immunoglobulin (IVIG) is highly effective in Kawasaki disease (KD), mechanisms are not understood and 10-20% of patients are treatment-resistant, manifesting a higher rate of coronary artery aneurysms. Murine models suggest that α2-6-linked sialic acid (α2-6Sia) content of IVIG is critical for suppressing inflammation. However, pro-inflammatory states also up-regulate endogenous levels of β-galactoside:α2-6 sialyltransferase-I (ST6Gal-I), the enzyme that catalyzes addition of α2-6Sias to N-glycans. We asked whether IVIG failures correlated with levels of α2-6Sia on infused IVIG or on the patient's own endogenous IgG. METHODS: We quantified levels of α2-6Sia in infused IVIG and endogenous IgG from 10 IVIG-responsive and 10 resistant KD subjects using multiple approaches. Transcript levels of ST6GAL1, in patient whole blood and B cell lines were evaluated by RT-PCR. Plasma soluble (s)ST6Gal-I levels were measured by ELISA. RESULTS: There was no consistent difference in median sialylation levels of infused IVIG between groups. However, α2-6Sia levels in endogenous IgG, ST6GAL1 transcript levels, and ST6Gal-I protein in serum from IVIG-resistant KD subjects were lower than in responsive subjects at both pre-treatment and one-year time points (p <0.001, respectively). CONCLUSIONS: Our data indicate sialylation levels of therapeutic IVIG are unrelated to treatment response in KD. Rather, lower sialylation of endogenous IgG and lower blood levels of ST6GALI mRNA and ST6Gal-I enzyme predict therapy resistance. These differences were stable over time, suggesting a genetic basis. Because IVIG-resistance increases risk of coronary artery aneurysms, our findings have important implications for the identification and treatment of such individuals

Band offsets in complex-oxide thin films and heterostructures of SrTiO3/LaNiO3 and SrTiO3/GdTiO3 by soft and hard X-ray photoelectron spectroscopy

The experimental determination of valence band offsets (VBOs) at interfaces in complex-oxide heterostructures using conventional soft x-ray photoelectron spectroscopy (SXPS, h nu 2000 eV). We demonstrate that the use of HXPS allows one to minimize charging effects and to probe more deeply buried interfaces in heterostructures such as SrTiO3/LaNiO3 and SrTiO3/GdTiO3. The VBO values obtained by HXPS for these interfaces are furthermore found to be close to those determined by first-principles calculations. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4795612]open112223sciescopu

Predictors of recurrence in the management of chordoid meningioma

INTRODUCTION: Management of chordoid meningiomas (CMs) is complicated by high rates of recurrence, particularly following subtotal resection. Optimal management is not established given the paucity of published experience. To identify prognostic factors for recurrence following resection, the authors conducted the largest systematic review of CMs to date. METHODS: A comprehensive search on MEDLINE (OVID and Pubmed), Scopus, Embase, and Web of Science utilizing the search terms “chordoid” AND “meningioma” was performed to identify all reports of pathologically confirmed intracranial CMs. RESULTS: A total of 221 patients were included, comprising 120 females and 101 males. Mean age, MIB-1/Ki67, and tumor size was 45.5 years, 4.3% (range:0.1-26.6%), and 4.1 cm (range: 0.8-10 cm), respectively. 5-, and 10- year progression free survival (PFS) was 67.5%, and 54.4%, respectively. Gross total resection (GTR) and subtotal resection (STR) was achieved in 172 and 48 patients, respectively. Adjuvant radiotherapy (RT) was given to 30 patients. Multivariate analysis found GTR was strongly correlated with decreased recurrence rates (HR 0.04, p =<0.0001), while higher MIB-1 labeling index (≥5% vs <5%) was associated with increased recurrence (HR 7.08; p=0.016). Adjuvant RT, age, gender, and tumor location were not associated with recurrence. CONCLUSION: GTR resection is the strongest predictor of tumor control, and should be the goal to minimize local progression. Additionally, higher MIB-1 labeling was associated with increased rates of tumor recurrence. Tumors that are subtotally resected or demonstrate higher MIB-1 are at greater recurrence and warrant consideration for RT and close long term follow up