Comparative analysis of antibiotic resistance, immunofluorescent colony staining, and a transgenic marker (bioluminescence) for monitoring the environmental fate of rhizobacterium

Field releases of the wild-type plant growth-promoting rhizobacterium Pseudomonas fluorescens 89B-27, its bioluminescent derivative GEM-8 (89B-27::Tn4431), and a spontaneous rifampin-resistant variant estimating the wild-type population. Seed and root samples were taken 0, 7, 14, 21, or 28, 35 or 42, and 70 days after planting in each year and processed for enumeration by spiral plating or immunofluorescent colony staining (IFC). In both years, the populations of 89B-27, R34, and GEM-8, as measured by IFC, were not significantly different (P > 0.05) from each other at each sampling time. However, the populations of R34 and GEM-8, as measured by spiral plating and differentiation based on their respective phenotypes, were significantly lower (P < 0.05) than the wild-type populations and their IFC-determined populations. These data indicate that traditional marker systems may underestimate populations and hence the survival and colonization of genetically marked bacteria.     

Randomized, double blind, dose-response trial across four oral doses of dolasetron for the prevention of acute emesis after moderately emetogenic chemotherapy. Oral Dolasetron Dose-Response Study Group

BACKGROUND: This double blind parallel group study assessed the acute antiemetic efficacy of four oral doses of dolasetron mesylate in cancer patients receiving their first course of intravenous chemotherapy with doxorubicin and/or cyclophosphamide. METHODS: Patients were randomized to receive 25, 50, 100, or 200 mg of dolasetron mesylate 30 minutes prior to chemotherapy and were monitored for nausea and emetic episodes for the next 24 hours. RESULTS: Three hundred and nineteen cancer patients at 32 sites completed the study. Most patients were female (81%); of this group, 69% had breast carcinoma. A highly statistically significant linear trend demonstrating improved response with higher doses was detected for complete response (no emetic episodes and no rescue medication) (P < 0.001), for complete plus major response (0-2 emetic episodes and no rescue medication) (P < 0.001), and for patient visual analog scale assessments of nausea (P = 0.001) and general satisfaction with antiemetic therapy (P = 0.001). No serious adverse events were noted. The most frequent adverse event was mild, self-limiting headache, which has been reported with other drugs in this class. CONCLUSIONS: Single oral doses of dolasetron mesylate were found to be effective in preventing acute emesis in cancer patients receiving moderately emetogenic chemotherapy.     

Paraoxonase (PON1) gene in mice: sequencing, chromosomal localization and developmental expression

PURPOSE: To retrospectively examine the optic disc photographs of a glaucoma population for optic disc haemorrhages, vascular occlusions and vascular abnormalities. METHODS: The optic disc photographs of 906 eyes of glaucoma and suspect glaucoma patients were examined. Optic disc photographs were taken annually, where possible, with the follow-up period varying between 1 and 14 years duration (mean, 2.89). Glaucoma patients are regularly reviewed every 4-6 months and glaucoma suspects every 1-2 years, depending on the ophthalmologist. Low-tension glaucoma patients were reviewed more frequently (mean, every 2.6 months). The results of the findings were compared to a control group of 39 subjects with a mean follow-up period of 7 years, using Fisher's exact test. RESULTS: It was found that during the period under review, 7.4% (n = 67) of eyes had optic disc haemorrhages. The highest frequency of optic disc haemorrhages (37.5%) was found in the low tension glaucoma group (P = 0.0001) followed by 11% of primary open-angle glaucoma eyes (P = 0.03). In the normal group there were three eyes with optic disc haemorrhages and one with a disc collateral, which constitutes 5.1% vascular changes in this sub-group. Of the study eyes 2.8% had central retinal vein occlusions, 1.3% branch vein occlusion, 1.2% disc vessel abnormalities (loops) and 1.1% disc collaterals. Discrete nerve fibre layer haemorrhages and microaneurysms were found in 0.8% and 1.8% of eyes, respectively. CONCLUSIONS: A total of 16.8% of the eyes observed in this study had either disc haemorrhages or vascular changes. The underlying trend of vascular and haemorrhagic changes in glaucoma are demonstrated in this sample, which is in general agreement with previous studies. The high percentage of optic disc haemorrhages in low tension glaucoma is highlighted. The presence of microaneurysms and nerve fibre layer haemorrhages is interesting but of unknown significance.     

Photo-polymerisation of composite resins measured by micro-Raman spectroscopy

The micro-Raman spectroscopy was used for measuring the photo-polymerisation of composite resins. The elevated spatial resolution of the technique revealed surface non-homogeneities via the intensity variations of a strong band at 1400 cm⁻¹ and the presence of weak bands around the CC and CO stretching frequencies. Values of the degree of monomer conversion (DC) were determined for samples of Z100 commercial composite irradiated with different wavelength laser beams. Two methods were used for obtaining DC values. The first one exploits band decompositions in the spectral region of interest around 1608 and 1637 cm⁻¹. The non-uniqueness of the decomposition introduces relevant uncertainties, which are amplified by unwanted weak bands. An alternative method, avoiding any fit procedure and exploiting the band shape conservation under irradiation, was found producing more reliable results. The 632 nm line of the He-Ne laser was used as an exciting source. The measurements of the DC versus time are reported for three different wavelengths of the irradiation light. Preliminary studies of the CO stretching bands are also reported. Their intensities decrease under irradiation and there are indications of a behaviour similar to that of the CC aliphatic band.     

Evolution and identification of lactic acid bacteria isolated during the ripening of Sardinian sausages

Lactic acid bacteria (LAB) were isolated during the production and the ripening of Sardinian sausage, a typical Italian dry fermented sausage. Samples were taken at different stages, and 112 strains were isolated. The isolates were characterized using the micromethod proposed by Font de Valdez et al. [Font de Valdez, G., Savoy de Giori, G., Oliver, G., & De Ruiz Holgado, A. P. (1993). Development and optimization of an expensive microsystem for the biochemical characterization of lactobacilli. Microbiologie Aliments Nutrition, 11, 215–219]. Schillinger and Lücke’s [Schillinger, U., & Lücke, F. K. (1987). Identification of lactobacilli from meat and meat products. Food Microbiology. (4), 199–208] scheme and the biochemical patterns given by Bergey’s Manual of Systematic Bacteriology [Bergey’s Manual of Systematic Bacteriology (1986). Baltimore: William and Wilkins] were used for preliminary identification. A PCR-based method was then used to confirm the results. LAB were the dominant flora during ripening. They consisted mainly of homofermentative mesophilic rods. Lactobacillus sakei (43,3%), Lactobacillus plantarum (16,6%) and Lactobacillus curvatus (13,3%) were the main isolates. The results of the biochemical identification methods agreed well with those of PCR-based identification (91% agreement).