Analysis of Derivatized Wall Teichoic Acids Confirms that a Mutation in Phage-Resistant Listeria monocytogenes Impacts Rhamnose Decoration.

Listeria monocytogenes is a Gram-positive foodborne pathogen that causes listeriosis, an illness that may result in serious health consequences or death. Wall teichoic acids (WTAs) are external cell wall glycopolymers that play many biological roles. Here, the WTA composition was determined for several phage-resistant mutant strains of L. monocytogenes. The strains included wild-type (WT) L. monocytogenes 10403S, and three phage-resistant mutant strains derived from 10403S, consisting of two well-characterized strains and one with unknown impact on cell physiology. Several WTA monomers were prepared from WT 10403S, as analytical standards. The WTA monomer fraction was then isolated from the mutant strains and the corresponding per-trimethylsilylated derivatives were analyzed by gas chromatography-flame ionization detection. WTA monomer, GlcNAc-Rha-Rbo, was detected in 10403S, and not detected in the phage-resistant strains known to lack rhamnose and N-acetylglucosamine; although the expected monomers GlcNAc-Rbo and Rha-Rbo were detected, respectively. GlcNAc-Rha-Rbo was also detected in strain UTK P1-0001, which is known to impact phage adsorption through an undetermined mechanism, albeit at a lower intensity than the WT 10403S, which is consistent with partial loss of function through truncation in RmlC protein. WTA monomers were also detected in an unpurified cell pellet, demonstrating that the method employed in this study can be used to rapidly screen L. monocytogenes without laborious WTA purification. This study lays the groundwork for future studies on WTA compositional analysis to support genomic data, and serves as a foundation for the development of new rapid methods for WTA compositional analysis.

Modulation of Brain-Derived Neurotrophic Factor (BDNF) Signaling Pathway by Culinary Sage (Salvia officinalis L.).

Culinary sage (Salvia officinalis L.) is a common spice plant in the mint family (Lamiaceae) well known for its distinctive culinary and traditional medicinal uses. Sage tea has been used traditionally as a brain-enhancing tonic and extracts from sage have been reported to have both cognitive and memory enhancing effects. Brain-derived neurotrophic factor (BDNF) is an endogenous signaling molecule involved in cognition and memory function. In this study, activity-guided fractionation employing preparative reverse-phase high performance liquid chromatography (RP-HPLC) of culinary sage extracts led to the discovery of benzyl 6-O-ß-D-apiofuranosyl-ß-D-glucoside (B6AG) as a natural product that upregulates transcription of neurotrophic factors in C6 glioma cells. Purified B6AG showed a moderate dose response, with upregulation of BDNF and with EC50 at 6.46 µM. To better understand the natural variation in culinary sage, B6AG was quantitated in the leaves of several commercial varieties by liquid chromatography-mass spectrometry (LC-MS). The level of B6AG in dried culinary sage was found to range from 334 ± 14 to 698 ± 65 µg/g. This study provided a foundation for future investigations, including quantitative inquiries on the distribution of B6AG within the different plant organs, explorations in optimizing post-harvest practices, and aid in the development of sage varieties with elevated levels of B6AG.

Safety, efficacy, and durability of laparoscopic adjustable gastric banding in a single surgeon U.S. community practice.

BACKGROUND: Although laparoscopic adjustable gastric banding (LAGB) has been increasing in popularity, controversy is ongoing in regard to its efficacy, safety and durability. Particular concern exists now that this technique is being adapted in the community setting. We report a single surgeon's experience of LAGB in a community practice serving a medium-size Midwest town in the United States. METHODS: From March 30, 2004 to December 2, 2009, 442 patients underwent LAGB (77% women; mean age 47 years, range 18-71; mean body mass index 47 kg/m(2), range 35-78). The maximal number of primary procedures performed in a 12-month period was 105. Follow-up information was available for 94% of patients. RESULTS: The perioperative mortality rate was 0%. The average percentage of excess weight loss was 27% at 6 months (n = 384), 38% at 12 months (n = 301), 44% at 18 months (n = 260), 48% at 24 months (n = 190), 51% at 36 months (n = 135), 58% at 48 months (n = 66), and 60% at 60 months (n = 31). By 60 months, 10% had failed to lose ≥25% of their excess body weight. The explantation rate was 1.8%. Gastric prolapse occurred in 2.0% of patients and erosion in 0.4% of patients. CONCLUSION: LAGB can be done safely in a community setting with acceptable weight loss and low failure rates. LAGB is less technical than other procedures; however, the results depend heavily on meticulous long-term follow-up. We have proposed a strategy that has been effective in the community setting.

Influence of menstrual cycle phase on pulmonary function in asthmatic athletes.

The main aim of this study was to investigate whether there is a relationship between menstrual cycle phase and exercise-induced bronchoconstriction (EIB) in female athletes with mild atopic asthma. Seven eumenorrheic subjects with regular 28-day menstrual cycles were exercised to volitional exhaustion on day 5 [mid-follicular (FOL)] and day 21 [mid-luteal (LUT)] of their menstrual cycle. Pulmonary function tests were conducted pre- and post-exercise. The maximal percentage decline in post-exercise forced expiratory volume in 1 s (FEV(1)) and forced expiratory flow from 25 to 75% of forced vital capacity (FEF(25-75%)) was significantly greater (P<0.05) on day 21 (mid-LUT phase) (-17.35+/-2.32 and -26.28+/-6.04%, respectively), when salivary progesterone concentration was highest, compared to day 5 (mid-FOL phase) (-12.81+/-3.35 and -17.23+/-8.20%, respectively), when salivary progesterone concentration was lowest. The deterioration in the severity of EIB during the mid-LUT phase was accompanied by worsening asthma symptoms and increased bronchodilator use. There was a negative correlation between the percent change in pre- to post-exercise FEV(1) and salivary progesterone concentration. However, no such correlation was found between salivary estradiol and the percentage change in pre- to post-exercise FEV(1). This study has shown for the first time that menstrual cycle phase is an important determinant of the severity of EIB in female athletes with mild atopic asthma. Female asthmatic athletes may need to adjust their training and competition schedules to their menstrual cycle and to consider the potential negative effects of the LUT phase of the menstrual cycle on exercise performance.

Dietary salt, airway inflammation, and diffusion capacity in exercise-induced asthma.

PURPOSE: Recent studies have supported a role for dietary salt as a modifier of the severity of exercise-induced asthma. The main aim of this study was to demarcate a possible mechanism by which dietary salt modification may alter exercise-induced airway narrowing in asthmatic patients. METHODS: Twenty-four patients participated in a randomized, double-blind crossover study. Subjects entered the study on their normal salt diet (NSD) and were then placed on either a low-salt diet (LSD) or high-salt diet (HSD) for 2 wk with a 1-wk washout period occurring between diets. Pre- and postexercise spirometry, pulmonary diffusion capacity (DLCO) and its subdivisions, and induced sputum were obtained on the NSD and at the end of each 2-wk treatment period (LSD and HSD). RESULTS: FEV1 decreased by 7.9 +/- 2.8% on LSD, 18.3 +/- 4.0% on NSD, and 27.4 +/- 3.2% on HSD at 20 min postexercise. The NSD and HSD induced significant reductions (P < 0.05) in DLCO and its subdivisions. However, postexercise pulmonary capillary blood volume significantly increased (P < 0.05) by 6.3 and 9.6 mL on NSD and HSD, respectively, compared with baseline values, with no significant change (P > 0.05) being observed on LSD. Postexercise-induced sputum neutrophil and eosinophil differential cell counts and induced sputum supernatant concentration of eosinophil cationic protein, interleukin (IL)-1beta, IL-8, leukotriene (LT) C(4)-E(4), LTB(4), and prostaglandin D(2) were significantly elevated (P < 0.05) on NSD and HSD compared with LSD. CONCLUSION: Our findings indicate that dietary salt loading enhances airway inflammation following exercise in asthmatic subjects, and that small salt-dependent changes in vascular volume and microvascular pressure might have substantial effects on airway function following exercise in the face of mediator-induced increased vascular permeability.

Comparison of the properties of rare variants of alpha1-proteinase inhibitor expressed in COS-1 cells and assessment of their potential as risk factors in human disease.

Among the more than 75 known variants of alpha(1)-proteinase inhibitor, a sub-population of rare, point mutations causing single amino acid replacements have been identified and classified as "at risk" alleles for development of pulmonary disease. In most cases, it is not clear how the amino acid replacements typical of these variants change the properties of the inhibitor to increase risk of disease in the affected individuals. To begin to address this question, we mutagenized a wild type alpha(1)-proteinase inhibitor cDNA to encode a panel of eight different point mutants reported to be associated with increased risk for development of pulmonary disease. These variants were then expressed in COS-l cells transiently transfected with plasmids containing the altered cDNAs. The effects of the mutations on the rates of secretion, cellular location, intracellular degradation, activity, stability, and tendency to aggregate were determined. Results of these studies show that, in some cases, the mutations affect the rate of secretion, the activity or both of these properties of alpha(1)-proteinase inhibitor in a manner consistent with its designation as an "at-risk" allele. In other cases, the mutations do not significantly change the properties of the inhibitor, suggesting that these may be normal variants and that their expression may not increase the risk of disease.