N-Glycosylation contributes to the limited cross-reactivity between hemagglutinin neuraminidase proteins of human parainfluenza virus type 4A and 4B

cDNAs encoding human parainfluenza virus type 4B (hPIV-4B) hemagglutinin neuraminidase (HN) protein were cloned and the nucleotide sequences were determined. A high degree of identity (81.4%) was observed between the nucleotide sequences of hPIV-4A and -4B HN proteins, and an 87.3% identity was found between the deduced amino acid sequences. This degree of identity is considered to be greater than immunological similarity between hPIV-4A and -4B HN proteins determined using monoclonal antibodies. To elucidate the causes of the antigenic difference between HN proteins of hPIV-4A and -4B, we constructed three cDNAs of hPIV-4B HN whose potential N-glycosylation sites were partially or completely the same as in hPIV-4A HN cDNA. We compared the antigenicity of the expressed wild-type and mutant proteins, and found that the antigenicities of the mutant hPIV-4B HN proteins were more similar to the hPIV-4A HN protein than to the non-mutant hPIV-4B HN protein. This study indicated that the antigenic diversity between hPIV-4A and -4B was partly caused by deletion or creation of glycosylation sites, showing that the point mutations resulting in deletion or creation of glycosylation sites is one of the initial steps leading to the division of virus into subtypes. Received: 21 January 2000     

Turtle-chicken chimera: an experimental approach to understanding evolutionary innovation in the turtle.

Turtles have a body plan unique among vertebrates in that their ribs have shifted topographically to a superficial layer of the body and the trunk muscles are greatly reduced. Identifying the developmental factors that cause this pattern would further our understanding of the evolutionary origin of the turtles. As the first step in addressing this question, we replaced newly developed epithelial somites of the chicken at the thoracic level with those of the Chinese soft-shelled turtle Pelodiscus sinensis (P. sinensis somites into a chicken host) and observed the developmental patterning of the grafted somites in the chimera. The P. sinensis somites differentiated normally in the chicken embryonic environment into sclerotomes and dermomyotomes, and the myotomes differentiated further into the epaxial and hypaxial muscles with histological morphology similar to that of normal P. sinensis embryos and not to that of the chicken. Epaxial dermis also arose from the graft. Skeletal components, however, did not differentiate from the P. sinensis sclerotome, except for small fragments of cartilage associated with the host centrum and neural arches. We conclude that chicken and P. sinensis share the developmental programs necessary for the early differentiation of somites and that turtle-specific traits in muscle patterning arise mainly through a cell-autonomous developmental process in the somites per se. However, the mechanism for turtle-specific cartilage patterning, including that of the ribs, is not supported by the chicken embryonic environment.     

Tacrolimus reduces urinary excretion of leukotriene E(4) and inhibits aspirin-induced asthma to threshold dose of aspirin

BACKGROUND: The exact mechanism of aspirin-induced asthma is not clear. It has been postulated that precipitation of asthma attacks by aspirin is linked to inhibition of COX activity and massive release of cysteinyl leukotriene into the airway. Tacrolimus, a macrolide-derived immunosuppressant, is used for immunosuppression in organ transplantation and also for allergic diseases such as atopic dermatitis. OBJECTIVE: We evaluated the effects of tacrolimus in aspirin-induced asthma by using a double-blind, crossover study design. METHODS: Twelve patients with aspirin-induced asthma (male:female, 3:9; mean age +/- SD, 36.7 +/- 7.2 years) received either tacrolimus (0.1 mg/kg) or placebo 2 hours before the threshold dose of oral aspirin. RESULTS: In the placebo arm, oral aspirin significantly decreased FEV 1 concomitant with significant increases in sputum eosinophilic cationic protein and urinary leukotriene E(4) levels. Tacrolimus significantly inhibited bronchoconstriction and abrogated aspirin-induced increase in both sputum eosinophilic cationic protein and urinary leukotriene E(4) levels. CONCLUSION: The current study suggested that tacrolimus inhibited bronchoconstriction to a threshold dose of aspirin by inhibition of cysteinyl leukotriene excretion.     

In vitro and in vivo antifungal activities of FX0685, a novel triazole antifungal agent with potent activity against fluconazole-resistant Candida albicans.

To evaluate the therapeutic potential of FX0685, a new triazole antifungal agent, for the treatment of opportunistic fungal infections, particularly systemic candidiasis and aspergillosis, in vitro and in vivo studies were performed using fluconazole (FLC), itraconazole (ITC) and/or amphotericin B (AMB) as reference drugs. A preliminary in vitro study showed that the antifungal activity of FX0685 against FLC-susceptible Candida albicans, several non-C. albicans Candida species and Cryptococcus neoformans was superior to that of FLC and comparable or superior to those of ITC and AMB, while the anti-Aspergillus fumigatus activity of FX0685 was to varying degrees lower than that of ITC. FX0685 appeared to be comparable to FLC and ITC in the treatment of murine systemic C. albicans and pulmonary A. fumigatus infection, respectively. The biological property of FX0685 was characterized by its potent in vitro and in vivo activity against FLC-resistant C. albicans. Part of this unique property was explained by the finding that it retained potent inhibitory activity against those CYP51 molecules in which amino acid substitutions confer a phenotype of resistance to FLC and some other azole derivatives. All of these results lead to the possibility that FX0685 may be a potential antifungal drug candidate for the treatment of various clinical forms of systemic candidiasis, including those caused by FLC-resistant C. albicans, as well as for the treatment of pulmonary aspergillosis.     

Fermented grain products, production, properties and benefits to health

Fermented foods such as Japanese traditional food “miso (fermented soy bean paste)” have been shown to be rich source of micronutrients with the potential to prevent various human diseases. We have introduced effects of a new dietary supplement of fermented grain foods mixture containing extracts from wheat germ, soybeans, rice bran, tear grass, sesame, wheat, citrus lemon, green tea, green leaf extract and malted rice under the trade name of antioxidant biofactor (AOB). Chemical analysis of AOB shows the presence of various phenolic compounds (catechins, rutin, genistin, daidzin, etc.). AOB has strong antioxidant properties and additional biological effects, which might be of importance in context with the prevention of degenerative diseases. This paper focuses on the effect of supplementing AOB in various animal models and humans.     

Characterization and expression of cDNA encoding coproporphyrinogen oxidase from a patient with hereditary coproporphyria

Hereditary coproporphyria (HCP) is an acute hepatic porphyriawith autosomal dominant inheritance, but with a variable degreeof clinical expression. Molecular cloning, sequencing and expressionof the defective gene for coproporphyrinogen oxidase (CPO) ina patient with HCP were carried out. Enzyme assays revealedthat CPO activity in EBV-transformed lymphoblastoid cells fromthe proband and one of her sisters was     

Astroglial responses against Abeta initially occur in cerebral primary cortical cultures: species differences between rat and cynomolgus monkey.

In the present study, we investigated how amyloid beta (Abeta) peptides initially affect neuronal cells in primary cerebral cortical cultures from rat and cynomolgus monkey. In these cultures, complicated interactions between glial and neuronal cells occur; moreover, synaptic interactions similar to those observed in vivo also occur between neuronal cells in these cultures. In this study, we applied low concentrations of Abeta to these well-characterized primary cultures to investigate how Abeta initially affects neurons or astroglial cells. In both rat and monkey cortical cultures, treatment with low concentrations of Abeta failed to drastically change or damage of neurons. Abeta treatment, however, significantly activated astrocytes, resulting in increased apolipoprotein E (ApoE) production. Rat astrocytes were more sensitive to Abeta than monkey astrocytes, and responded to Abeta via a different mechanism. In monkey astrocyte cultures, only direct treatment with Abeta increased ApoE production. In rat astrocyte cultures, however, treatment with conditioned media from cortical cultures grown with Abeta increased ApoE production, indicating that some sort of neuron-derived soluble factor(s) was also involved in activating rat astrocytes. These species differences suggest that monkey cortical cultures would be more useful as an in vitro model system to understand the details of how Abeta accumulates in the human brain, since monkeys are phylogenetically more similar to humans.     

Neuropsin is essential for early processes of memory acquisition and Schaffer collateral long-term potentiation in adult mouse hippocampus in vivo

Long-term potentiation (LTP) is thought to be particularly important in the acquisition of hippocampus-associated memory, in part because it develops quickly and persists for indefinite periods. Extracellular proteolysis has been hypothesized to contribute to LTP by modifying adhesive relations of synapses and thus the morphology of excitatory synapses. Here we report that neuropsin (NP), an extracellular serine protease, is critically involved in the formation of both the potentiation effect and hippocampus-dependent forms of memory. NP-knockout mice were significantly impaired in the Morris water maze and Y-mazes and failed to exhibit early phase LTP induced by a single tetanus. Potentiation was also impaired or completely blocked by in vivo application of a specific inhibitor or a neutralizing monoclonal antibody for NP. Intriguingly, recombinant (r-) NP alone, without tetanic stimulation, elicited either long-lasting potentiation or depression, depending on the applied dose. The r-NP-elicited potentiation was occluded by prior induction of LTP, while theta-burst-elicited LTP was occluded by application of r-NP alone, suggesting that the two forms of plasticity have a common signalling pathway. r-NP-elicited potentiation and depression increased phosphorylation at different sites on the GluR1 subunit of the AMPA receptor that had previously been associated with LTP or long-term depression. Thus, we conclude that NP is necessary for establishment of LTP and has a significant role in memory acquisition.     

Muscle metabolism during exercise using phosphorus-31 nuclear magnetic resonance spectroscopy in adolescents

Very little has been reported on muscle energetics during exercise in adolescents. This is attributable to the difficulty of subjecting children to muscle biopsy. The purpose of this study was to investigate the characteristics of muscle metabolism during exercisein vivo in adolescents by comparing firstly, with adults and secondly, the differences resulting from physical activity using phosphorus-31 nuclear magnetic resonance (³¹PNMR) spectroscopy. The subjects were boys aged 12 to 15 years, comprising 21 trained boys and 23 control boys, and 6 adults controls. The ratio of phosphocreatine (PCr):(PCr + P_i), where P_i is inorganic phosphate intracellular pH at exhaustion and the time constant of PCr during recovery were measured in all the subjects using³¹PNMR. Both groups of children showed higher values of PCr:(PCr + P_i) and intracellular pH at exhaustion than did the adult control group (P < 0.01 orP < 0.05). However, no significant differences were found between the trained boys and the control boys with respect to PCr:(PCr + P_i) and intracellular pH at exhaustion. On the other hand, we found the same values for PCr time constant in all groups. This result suggested no differences of the muscle oxidative capacity between children and adults. We concluded that the adolescents, aged 12 to 15 years in both the trained and control groups, had less glycolytic ability during exercise than the adults.