Chloride attachment negative-ion mass spectra of sugars by combined liquid chromatography and atmospheric pressure chemical ionization mass spectrometry

A method has been developed for the rapid determination of sugars, including molecular weight measurements, using high-performance liquid chromatography coupled with negative-ion, atmospheric-pressure chemical-ionization mass spectrometry. The chromatography was carried out on a 250 × 4 mm I.D. column packed with 7 μm NH₂-silica. The mobile phase consisted of a high percentage of methanol or acetonitrile with a small amount of chloroform. During the mass spectrometry, a strong base is formed from the polar solvent molecules by corona discharge, followed by ion—molecule reactions in the chemical ionization ion source (e.g. the methoxy anion is formed from methanol). This strong base reacts with the chloroform, generating chloride ions, which in turn react with the neutral sugar molecules as they elute from the chromatograph. The chloride ion and sugar interactions yield chloride-attachment ions, which are further stabilized by successive collisions. In this method, authentic monosaccharides and some oligosaccharides show dominant quasi-molecular ions, [M + Cl]⁻, with little fragmentation, and it is particularly useful for the molecular weight determination of sugars.     

C-terminal sequencing of protein. A novel partial acid hydrolysis and analysis by mass spectrometry.

Peptides or proteins were hydrolyzed by vapors of 90% pentafluoropropionic acid or heptafluorobutyric acid at 90 degrees C for various time periods. The hydrolyzate mixtures analyzed by both fast-atom-bombardment and electrospray ionization mass spectrometry showed a series of C-terminal successive degradation molecular ions. The degradation reaction may be due to the selective formation of an oxazolone ring at the C-terminal amino acid, followed by hydrolytic removal of the C-terminal amino acid. The major side reactions were cleavages of the peptide bonds at the C side of the internal aspartic acid residue and the N side of serine residue.     

Effect of the pH of culture medium on the alkalophilicity of a species of Bacillus

The amino acid incorporation and -aminoisobutyric acid (AIB) uptake of an alkalophilic Bacillus grown at pH 8.2 (the pH 8-bacteria) were much less pH dependent (less alkalophilic) than those of the organisms grown at pH 10.0 (the pH 10-bacteria), respectively. The rate of AIB uptake of the pH 10-bacteria was almost the same as that of the pH 8-bacteria, while the rate of amino acid incorporation of the pH 10-bacteria was higher than that of the pH 8-bacteria in alkaline environments. The colloidal titration with clupein showed that the amount of negative charge on the pH 10-bacteria was greater than that of the pH 8-bacteria in alkaline environments. Considerable difference in protein composition was observed between the membranes of the pH 8-and 10-bacteria, while no difference was observed in phospholipid composition.Abbreviations AIB Amino-isobutyric acid     

Genetic structure of <Emphasis Type="Italic">Cerasus jamasakura</Emphasis>, a Japanese flowering cherry,revealed by nuclear SSRs: implications for conservation

The genetic resources of a particular species of flowering cherry, Cerasus jamasakura, have high conservation priority because of its cultural, ecological and economic value in Japan. Therefore, the genetic structures of 12 natural populations of C. jamasakura were assessed using ten nuclear SSR loci. The population differentiation was relatively low (F _ST, 0.043), reflecting long-distance dispersal of seeds by animals and historical human activities. However, a neighbor-joining tree derived from the acquired data, spatial analysis of molecular variance and STRUCTURE analysis revealed that the populations could be divided into two groups: one located on Kyusyu Island and one on Honshu Island. Genetic diversity parameters such as allelic richness and gene diversity were significantly lower in the Kyushu group than the Honshu group. Furthermore, STRUCTURE analysis revealed that the two lineages were admixed in the western part of Honshu Island. Thus, although the phylogeographical structure of the species and hybridization dynamics among related species need to be evaluated in detail using several marker systems, the Kyusyu Island and Honshu Island populations should be considered as different conservation units, and the islands should be regarded as distinct seed transfer zones for C. jamasakura, especially when rapid assessments are required.     

ALDH2 polymorphism for the risk of cervical carcinogenesis

To investigate the clinical significance of ALDH2 genetic polymorphisms in cervical carcinogenesis. ALDH2 polymorphisms together with human papillomavirus (HPV) types were examined in a total of 195 cervical smear in exfoliated cervical cell samples using Real-Time polymerase chain reaction (PCR) System. The frequency for the AG+AA genotype was seven in the normal group (70.0 %), 16 in the LSIL group (57.1 %), and 27 in the HSIL group (90.0 %). A significant difference was found between the LSIL and HSIL groups (P = 0.0064). Patients with HSIL lesions frequently had high-risk HPV infections and concurrently belonged to the AG+AA group. ALDH2 genotype in cervical cell samples may be associated with more severe precancerous lesions of the cervix in a Japanese population.     

Anti-microtubule ‘plinabulin’ chemical probe KPU-244-B3 labeled both α- and β-tubulin

Plinabulin (1, NPI-2358), a potent microtubule-targeting agent derived from the natural diketopiperazine ‘phenylahistin’ with a colchicine-like tubulin depolymerization activity, is an anticancer agent undergoing Phase II clinical trials in four countries including the United States. In order to understand the precise binding mode of plinabulin with tubulin, a new bioactive biotin-tagged photoaffinity probe 4 (KPU-244-B3) was designed and synthesized. Probe 4 showed significant binding affinity to tubulin in a binding assay, and selectively bound to tubulin in an HT-1080 cell lysate without photo-irradiation. In a tubulin photoaffinity labeling study, probe 4 labeled both α- and β-tubulin subunits and these interactions were competitively inhibited by plinabulin during photo-irradiation. These results suggest that plinabulin binds in the boundary region between α- and β-tubulin near the colchicine binding site, and not inside the colchicine binding cavity.     

Cytology of pleural effusion associated with disseminated infection caused by varicella-zoster virus in an immunocompromised patient. A case report

BACKGROUND: Pleural effusion caused by varicella-zoster virus (VZV) is rare. We report a case of a woman with acute lymphocytic leukemia (ALL) who developed a pleural effusion caused by VZV infection. CASE: A 55-year-old woman with ALL treated with consolidation therapy developed skin vesicles and a pleural effusion. Pleural fluid smears contained numerous mesothelial cells, which had ground-glass nuclei or eosinophilic nuclear inclusions. Some multinucleated giant cells were also seen. Electron microscopic examination revealed intranuclear virus particles, about 150 nm in diameter, in some mesothelial cells. Tissue samples from the skin, lungs, pleura, liver, pancreas, kidneys and gastrointestinal tract, obtained at autopsy, contained many virus-infected cells. They were positive for VZV glyco-protein 1 by immunohistochemistry. CONCLUSION: VZV infection should be considered in the differential diagnosis of an unexplained exudative pleural effusion, especially in immunocompromised hosts.