Metabolomic profile of milk fermented with Streptococcus thermophilus cocultured with Bifidobacterium animalis ssp. lactis, Lactiplantibacillus plantarum, or both during storage

In this study, the microbial interactions among cocultures of Streptococcus thermophilus (St) with potential probiotics of Bifidobacterium animalis ssp. lactis (Ba) and Lactiplantibacillus plantarum (Lp) in fermented milk were investigated during a storage period of 21 d at 4°C, in terms of acidifying activity (pH and titratable acidity), viable counts, and metabolites. A nontargeted metabolomics approach based on ultra-high-performance liquid chromatography coupled with mass spectrometry was employed for mapping the global metabolite profiles of fermented milk. Probiotic strains cocultured with St accelerated milk acidification, and improved the microbial viability compared with the single culture of St. The St-Ba/Lp treatment manifested a higher bacteria viability and acidification ability in comparison with the St-Ba or the St-Lp treatment. Relative quantitation of 179 significant metabolites was identified, including nucleosides, AA, short peptides, organic acids, lipid derivatives, carbohydrates, carbonyl compounds, and compounds related to energy metabolism. The principal component analysis indicated that St treatment and coculture treatments displayed a complete distinction in metabolite profiles, and Lp had a larger effect than Ba on metabolic profiles of fermented milk produced by cofermentation with St during storage. The heat map in combination with hierarchical cluster analysis showed that the abundance of metabolites significantly varied with the starter cultures over the storage, and high abundance of metabolites was observed in either St or coculture samples. The St-Ba/Lp treatment showed relatively high abundance for the vast majority of metabolites. These findings suggest that the profile of the metabolites characterizing fermented milk samples may depend on the starter cultures, and incorporation of probiotics may considerably influence the metabolomic activities of fermented milks.

Topological nature of the node-arc semimetal PtSn4 probed by de Haas-van Alphen quantum oscillations

Dirac node arc semimetal state is a new topological quantum state which is proposed to exist in PtSn₄ (Wu et al 2016 Dirac node arcs in PtSn₄ Nat. Phys. 12 667-71). We present a systematic de Haas-van Alphen quantum oscillation study on this compound. Two intriguing oscillation branches, i.e. F ₁ and F ₂, are detected in the fast Fourier transformation spectra, both of which are characterized to possess tiny effective mass and ultrahigh quantum mobility. And the F ₂ branch exhibits an angle-dependent nontrivial Berry phase. The features are consistent with the existence of the node arc semimetal state and shed new light on its complicated Fermi surfaces and topological nature.

Effect of optical digitizer selection on the application accuracy of a surgical localization system-a quantitative comparison between the OPTOTRAK and flashpoint tracking systems

Application accuracy is a crucial factor for stereotactic surgical localization systems, in which space digitization camera systems are one of the most critical components. In this study we compared the effect of the OPTOTRAK 3020 space digitization system and the FlashPoint Model 3000 and 5000 3D digitizer systems on the application accuracy for interactive localization of intracranial lesions. A phantom was mounted with several implantable frameless markers which were randomly distributed on its surface. The target point was digitized and the coordinates were recorded and compared with reference points. The differences from the reference points represented the deviation from the "true point." The root mean square (RMS) was calculated to show the differences, and a paired t-test was used to analyze the results. The results with the phantom showed that, for 1-mm sections of CT scans, the RMS was 0.76 +/- 0. 54 mm for the OPTOTRAK system, 1.23 +/- 0.53 mm for the FlashPoint Model 3000 3D digitizer system, and 1.00 +/- 0.42 mm for the FlashPoint Model 5000 system. These preliminary results showed that there is no significant difference between the three tracking systems, and, from the quality point of view, they can all be used for image-guided surgery procedures.

A case of basophilic leukemia bearing simultaneous translocations t(8;21) and t(9;22)

We report a case of basophilic leukemia with simultaneous translocations of t(8;21) and t(9;22). The patient's clinical and hematologic findings were characteristic only of t(9;22) but not of t(8;21). This unusual cytogenetic phenomenon raises a challenge to the current concepts of primary chromosomal abnormalities in cancer.

Fatty acid content of marine oil capsules

The use of dietary omega 3 fatty acid capsules has been associated with a decrease in plasma triglyceride levels. In addition, populations consuming diets rich in fish appear to have a decreased incidence of cardiovascular disease. Eicosapentaenoic acid (EPA, 20:5 omega 3) and docosahexaenoic acid (DHA, 22:6 omega 3) are major fatty acids in fish oils. It is believed that fish oils exert their biologic effect through these fatty acids. Many individuals are currently taking fish oil capsules to lower lipids, increase bleeding time, and possibly decrease cardiovascular risk. These capsules also have been classified as food additives with less stringent controls on content. We assessed the fatty acid, cholesterol, and vitamin A and E content of eight commercially available capsules along with cod liver oil. The content of EPA was found to range from 8.7-26.4% (wt %) with a mean of 17.3% (82.4% of labeled content), and that of DHA from 8.9-17.4% with a mean of 11.5% (90.0% of labeled content) as assessed by capillary column gas-liquid chromatography. The mean content of the polyunsaturated omega 3 fatty acids was 31.9%, and that of the omega 6 fatty acids was 1.4%. The content of saturated fatty acids was 32.0%, and that of monounsaturated fatty acids was 25.1%. Cholesterol content was low, with a range of 0.7-8.3 mg/g, the alpha-tocopherol range was 0.62-2.24 mg/g, and the range of retinyl esters was 0.4-298.4 micrograms/g. Cod liver oil had substantially more retinyl esters (2450.1 micrograms/g) than did fish oil capsules.(ABSTRACT TRUNCATED AT 250 WORDS)

Sequential observation of clinical and karyotypic evolution in a patient with myelodysplastic syndrome

This paper reports an interesting case of myelodysplastic syndrome (MDS), whose bone marrow karyotype at diagnosis was 46, XY, t(16;17) (q12;q25). Fourteen months later, the disease transformed into erythroleukemia, and several correlative clones with hyperdiploid appeared at the same time. Thus, we consider that detecting karyotypic evolution may help evaluate the prognosis of MDS.

Criteria for essential fatty acid deficiency in plasma as assessed by capillary column gas-liquid chromatography

To develop criteria for deficiency of essential fatty acids (EFA), we used capillary-column gas-liquid chromatography to determine fatty acids (percentage of total fatty acids) in plasma obtained in the fasting state from 56 reference subjects and from 10 patients with intestinal fat malabsorption and suspected EFA deficiency. Fatty acid evaluations (percentage of total fatty acids) that allowed for a clear distinction (P less than 0.01) between reference subjects and patients, based on values two standard deviations below or above the reference mean, included values for linoleic acid (18:2w6) below 27%, and values for palmitic acid (16:0), palmitoleic acid (16:1w7), oleic acid (18:1w9), vaccenic acid (18:1w7), and Mead acid (20:3w9) exceeding 21%, 2.6%, 23.3%, 2.1%, and 0.21%, respectively. Ratios of total EFA to total non-EFA of less than 0.60 and of Mead acid to arachidonic acid of greater than 0.025 also served to identify patients, and were not found in reference subjects. Significant inverse correlations between percentages of plasma EFA and plasma mono-unsaturated fatty acids were noted. Our reference-interval data can be used to assess normality of plasma EFA status.