Stable isotope dilution mass spectrometry for the simultaneous determination of cortisol, cortisone, prednisolone and prednisone in plasma.

A capillary gas chromatographic-mass spectrometric method for the simultaneous determination of cortisol, cortisone, prednisolone and prednisone in human plasma is described. [1,1,19,19,19-2H5]Cortisol, [1,1,19,19,19-2H5]cortisone, [1,19,19,19-2H4]prednisolone and [1,19,19,19-2H4]prednisone were used as internal standards. Formation of the bismethylenedioxy-3-heptafluoro-n-butyryl (BMD-HFB) derivatives made possible the separation of the four corticosteroids with good gas chromatographic behaviour. The new double derivatization has been demonstrated to be of value for sensitive and selective quantification by this technique. Detection was performed by monitoring the molecular ion (M+) of the BMD-HFB derivatives for cortisone and prednisolone, the [M - 18]+ ion for cortisol, and the [M - 30]+ ion for prednisone. The method requires no complex corrections for contributions and provides good accuracy and precision.     

Ejection,excitation and decomposition of large clusters from the surface of group II,III and IV elements by excimer laser excitation

Light emission and scattering are analyzed for the plume of vapor produced by laser excitation of the solid target of Group II, III and IV elements. Spectroscopic evidences suggest that the plume consists of microclusters of target elements. The size of microclusters is estimated to be 0.6 nm in diameter.     

Reheating as a surface effect

We describe a new mechanism for reheating the Universe through evaporation of a surface charge of a fragmented inflaton condensate. We show that for a range of Yukawa coupling of the inflaton to the matter sector evaporation gives rise to a much smaller reheat temperature compared to the standard perturbative decay. As a consequence, reheating through a surface effect could solve the gravitino and moduli overproduction problem in inflationary models without fine tuning the Yukawa sector.     

Anomalous resistivity near Néel temperature due to the critical scattering: Antifferomagnet

Critical behaviour of the temperature derivative of the electrical resistivity at the Néel temperature is treated. For a small Fermi wave vector, the divergence is the same as that of the specific heat both above and below the Néel temperature. For a large Fermi wave vector, in paramagnetic region, the contributions from the critical and the other regions of q-space are of the same divergence as the specific heat but of different signs from each other. Below Néel temperature, the gap effect is the main origin of divergence.     

Evidence for a modulated ordering in CeB6 due to the Kondo effect

Neutron diffraction experiments have been performed on CeB₆ single crystals to investigate the magnetic order in zero field. CeB₆ orders anti-ferromagnetically below T_N = 2.8 ± 0.1 K with a second order phase transition. The magnetic order is defined by the two wave vectors $\text{k}{}_1\text{= 〈}\text{1}\text{4}\text{1}\text{4}\text{0〉}$ and $\text{k}{}_2\text{= 〈}\text{1}\text{4}\text{1}\text{4}\text{1}\text{2}\text{〉}$. No magnetic intensity anomaly has been detected at the transition between the phases II and III. This transition is quite original and corresponds only to a phase shift of the modulation. This unusual behaviour can be understood if the effective Kondo effect is the same in both phases. The structure of the low temperature phase III is probably a helical order in (001) planes with moments along the fourfold axes in constrast with the crystal field anisotropy. In phase III there is a homogeneous moment reduction due to the Kondo effect whereas in the phase II it is non-homogeneous with a sequence (+ μ0 - μ0) containing non-magnetic planes.     

Characterization of a mesophilic aliphatic-aromatic copolyester-degrading fungus

We isolated 5 mesophilic microorganisms that form clear zones around the colony on an opaque medium containing the aliphatic-aromatic copolyester poly(60 mol% butylene adipate-co-40 mol% butylene terephthalate) (PBAT). Among all strains, the fungal strain NKCM1712 degraded PBAT at the fastest rate (3.5 ± 0.3 μg cm⁻² h⁻¹). Genetic and morphological analyses revealed that this strain was closely related to Isaria fumosorosea (phylum Ascomycota). Mass spectroscopic analysis revealed that the degradation products were T, AB, TB, BAB, and ABT (T, terephthalic acid unit; A, adipic acid unit; B, 1,4-butanediol unit)] in the culture of the strain that used PBAT as the sole carbon source. Furthermore, the PBAT degradation ability of this strain in terms of BOD suggested that it could utilize the PBAT degradation products as growth substrates. This is the first report of a mesophilic strain that can mineralize an aliphatic-aromatic polyester into carbon dioxide on its own.     

The chemical synthesis of a cyclic oligosaccharide derivative with branching

A cyclic oligosaccharide derivative was synthesized by cationic ring-opening polymerization of an anhydrodisaccharide derivative under high vacuum in dichloromethane with 20 mol% of PF₅ as initiator. Analysis of the spectral results showed that the oligomer chain is composed of only 3 glucose units connected by -1,6 linkages with a glucopyranosyl branching unit at C-4 of each sugar residue in the main chain.     

Fluorous solvent for cell culture

Incubation of mouse melanoma B16 cells in fluorous solvents with low boiling point such as perfluoromethylcyclohexane, 1,1,1,3,3,3-hexafluoro-2-propanol, ethylpentafluoropropionate resulted in cell death. However, cells lived up to 2 days in fluorous alcohols such as 2,2,3,3,4,4,5,5-octafluoro-1-pentanol and 3,3,4,4,5,5,6,6,6-nonafluoro-1-hexanol with relatively higher fluorine content. Remarkably, cells survived deprived of nutrition up to 4 days when incubated in 2,2,3,3,4,4,5,5,6,6,6-undecafluoro-1-hexanol or in 2,2,3,3,4,4,5,5,6,6,7,7-dodecafluoroheptanol that have the most number of fluorine atoms (11 and 12, respectively) among the perfluoroalkyl alcohols used, and with boiling points of 128 °C and 169 °C, respectively.     

Effect of Anomeric Linkage on the Sialylation of Glycosides by Cells

The synthesis of sialylated glycosides using saccharide primers and cells was investigated. α · and β · Saccharide primers were chemically synthesized and introduced into B16 melanoma cells to prime oligosaccharide synthesis. Incorporation of α‐ and β‐dodecyl lactosides into B16 cells resulted in the sialylation of the galactose residue to give GM3‐type oligosaccharides. The β‐dodecyl galactoside primer was sialylated but the α‐dodecyl galactoside primer was not. Both the α‐ and β‐dodecyl glucoside primers were not elongated. In the glycosylation of primers by cells, this research confirmed that sialyl transferases tolerate acceptor modifications and are permissive to primer elongation regardless of the α‐ or β‐linkage to the aglycon unit. However, the presence of the terminal galactose residue that is β‐linked to the adjacent saccharide or aglycon unit is essential for sialylation by cellular enzymes to occur.