Changes in phenylalanine ammonia-lyase activity in Satsuraa mandarin fruit during ontogeny

PAL activity in young fruits of Citrus unshiu was initiallyvery high. It decreased gradually as the fruit grew and afterthe "June drop", declined markedly. PAL behavior appears tobe closely related to the tissue differentiation of fruit. Proteincontent of the fruit showed a pattern of change similar to thatof PAL activity. Also, the amount of hesperidine was high inimmature fruit. Accumulation of hesperidine per fruit was greatlyenhanced as growth of the fruit progressed, but after PAL activityhad almost disappeared, the accumulation ceased. ¹Present address: Kozo Keikaku Engineering Incorporation, Nakano,Tokyo, Japan. (Received March 16, 1973; )     

Molecular profiling of Lactobacillus, Streptococcus, and Bifidobacterium species in feces of active racehorses

Diversity and compositions of the Lactobacillus, Streptococcus, and Bifidobacterium group in the feces of six healthy, actively racing horses (Thoroughbreds) were analyzed by using PCR-denaturing gradient gel electrophoresis (DGGE) and real-time PCR with primer sets specific for each group. PCR-DGGE analysis of the feces showed that Lactobacillus equi, Lactobacillus johnsonii, a phylogenetic relative of Lactobacillus salivarius, a phylogenetic relative of Lactobacillus gastricus, and Weissella confusa were predominant in almost all of the feces tested, and Streptococcus bovis/Streptococcus equinus was predominant in the Streptococcus group. The Bifidobacterium group was not detected by single-PCR but atypical species of the group were found in three of the six Thoroughbreds tested by nested-PCR. Calculation and estimation of lactic acid bacteria and bifidobacteria revealed that lactic acid bacteria were predominant in the feces and bifidobacteria were minor. These results indicate that the community of lactic acid bacteria and bifidobacteria in horse feces are unique because of the presence of specific species for horse feces and a minority of the Bifidobacterium group. Repeated tests of the feces from the same horse over 3 months showed that the diversity and composition of lactic acid bacteria and bifidobacteria in the feces was basically stable throughout the test period.     

Stimulation of membrane permeability transition by alpha-lipoic acid and its biochemical characteristics

Mitochondria play an important role in apoptosis by generating reactive oxygen species (ROS) and inducing membrane permeability transition (MPT). Recent studies on alpha-lipoic acid (LA) and its reduced form, dihydrolipoic acid, suggest that these agents (LAs) inhibit apoptosis of cells by means of their antioxidant activity. On the other hand, LAs also stimulate Ca2+-dependent mitochondrial MPT and induce apoptosis of certain cells. Thus, the role of LAs in apoptotic cell death remains obscure. We investigated the mechanism of LA-induced MPT of mitochondria. Biochemical analysis revealed, in the presence of Ca2+, inorganic phosphate and succinate, LA induced uncoupling of oxidative phosphorylation, stimulated oxidation of pyridine nucleotides and enhanced Ca2+-induced MPT, as characterized by decrease in Ca2+ loading, ROS generation, oxidation of thiol groups of adenine nucleotide translocator, membrane depolarization, swelling, and cytochrome c release in an incubation time and concentration dependent manner. LA also stimulated hydroxyl radical-induced MPT in a alpha-tocopherol-inhibitable manner. Cyclosporine A, a potent inhibitor of mitochondrial MPT, inhibited all these events induced by LA. These results indicate that, under certain conditions, LA stimulates Ca2+-induced MPT through the decrease in loading capacity of Ca2+ and that MPT is involved in LA-induced apoptotic cell death. Since fairly high doses of LA have been used as a dietary supplement, the possible occurrence of such side effects, including mitochondrial dysfunction and induction of apoptosis in normal tissues, should be studied.     

Chromosome banding in three species of <Emphasis Type="Italic">Hypsiboas</Emphasis> (Hylidae,Hylinae), with special reference to a new case of B-chromosome in anuran frogs and to the reduction of the diploid number of 2n = 24 to 2n = 22 in the genus

The chromosomes of hylids Hypsiboas albopunctatus, H. raniceps, and H. crepitans from Brazil were analyzed with standard and differential staining techniques. The former species presented 2n = 22 and 2n = 23 karyotypes, the odd diploid number is due to the presence of an extra element interpreted as B chromosome. Although morphologically very similar to the small-sized chromosomes of the A complement, the B was promptly recognized, even under standard staining, on the basis of some characteristics that are usually attributed to this particular class of chromosomes. The two other species have 2n = 24, which is the chromosome number usually found in the species of Hypsiboas karyotyped so far. This means that 2n = 22 is a deviant diploid number, resulted from a structural rearrangement, altering the chromosome number of 2n = 24 to 2n = 22. Based on new chromosome data, some possibilities were evaluated for the origin of B chromosome in Hypsiboas albopunctatus, as well as the karyotypic evolution in the genus, leading to the reduction in the diploid number of 2n = 24 to 2n = 22.     

Effect of Streptococcus salivarius K12 on the in vitro growth of Candida albicans and its protective effect in an oral candidiasis model

Oral candidiasis is often accompanied by severe inflammation, resulting in a decline in the quality of life of immunosuppressed individuals and elderly people. To develop a new oral therapeutic option for candidiasis, a nonpathogenic commensal oral probiotic microorganism, Streptococcus salivarius K12, was evaluated for its ability to modulate Candida albicans growth in vitro, and its therapeutic activity in an experimental oral candidiasis model was tested. In vitro inhibition of mycelial growth of C. albicans was determined by plate assay and fluorescence microscopy. Addition of S. salivarius K12 to modified RPMI 1640 culture medium inhibited the adherence of C. albicans to the plastic petri dish in a dose-dependent manner. Preculture of S. salivarius K12 potentiated its inhibitory activity for adherence of C. albicans. Interestingly, S. salivarius K12 was not directly fungicidal but appeared to inhibit Candida adhesion to the substratum by preferentially binding to hyphae rather than yeast. To determine the potentially anti-infective attributes of S. salivarius K12 in oral candidiasis, the probiotic was administered to mice with orally induced candidiasis. Oral treatment with S. salivarius K12 significantly protected the mice from severe candidiasis. These findings suggest that S. salivarius K12 may inhibit the process of invasion of C. albicans into mucous surfaces or its adhesion to denture acrylic resins by mechanisms not associated with the antimicrobial activity of the bacteriocin. S. salivarius K12 may be useful as a probiotic as a protective tool for oral care, especially with regard to candidiasis.     

Determination of iodide in urine using electrospray ionization tandem mass spectrometry

A rapid and sensitive electrospray ionization (ESI) tandem mass spectrometry (MS–MS) procedure was developed for the determination of iodide (I⁻). A gold (Au) and I⁻ complex was formed immediately after the addition of the chelating agent NaAuCl₄ to I⁻ solution, and was extracted with methyl isobutyl ketone. One to five microliters of the extract were injected directly into an ESI–MS–MS instrument. I⁻ quantification was performed by selecting reaction monitoring of the product ion I⁻ at m/z 127 derived from the precursor ion ¹⁹⁷AuI₂⁻ at m/z 451. I⁻ concentration was measured in the quantification range from 10⁻⁷ to 10⁻⁵ M using 50 μL of solution within 10 min. Iodate was reduced to I⁻ with ascorbic acid and determined. I⁻ concentration in reference urine 2670a was measured after treatments.     

Loss of disability-adjusted life years due to heat-related sleep disturbance in the Japanese

Sleep and Biological Rhythms - The purpose of this study was to quantify the sleep disturbances caused by climate change using disability-adjusted life years (DALY). The revised sleep quality index...