Emergence of Pathogenic Coronaviruses in Cats by Homologous Recombination between Feline and Canine Coronaviruses

Type II feline coronavirus (FCoV) emerged via double recombination between type I FCoV and type II canine coronavirus (CCoV). In this study, two type I FCoVs, three type II FCoVs and ten type II CCoVs were genetically compared. The results showed that three Japanese type II FCoVs, M91-267, KUK-H/L and Tokyo/cat/130627, also emerged by homologous recombination between type I FCoV and type II CCoV and their parent viruses were genetically different from one another. In addition, the 3′-terminal recombination sites of M91-267, KUK-H/L and Tokyo/cat/130627 were different from one another within the genes encoding membrane and spike proteins, and the 5′-terminal recombination sites were also located at different regions of ORF1. These results indicate that at least three Japanese type II FCoVs emerged independently. Sera from a cat experimentally infected with type I FCoV was unable to neutralize type II CCoV infection, indicating that cats persistently infected with type I FCoV may be superinfected with type II CCoV. Our previous study reported that few Japanese cats have antibody against type II FCoV. All of these observations suggest that type II FCoV emerged inside the cat body and is unable to readily spread among cats, indicating that these recombination events for emergence of pathogenic coronaviruses occur frequently.     

Persistent Release of IL-1s from Skin Is Associated with Systemic Cardio-Vascular Disease,Emaciation and Systemic Amyloidosis: The Potential of Anti-IL-1 Therapy for Systemic Inflammatory Diseases

The skin is an immune organ that contains innate and acquired immune systems and thus is able to respond to exogenous stimuli producing large amount of proinflammatory cytokines including IL-1 and IL-1 family members. The role of the epidermal IL-1 is not limited to initiation of local inflammatory responses, but also to induction of systemic inflammation. However, association of persistent release of IL-1 family members from severe skin inflammatory diseases such as psoriasis, epidermolysis bullosa, atopic dermatitis, blistering diseases and desmoglein-1 deficiency syndrome with diseases in systemic organs have not been so far assessed. Here, we showed the occurrence of severe systemic cardiovascular diseases and metabolic abnormalities including aberrant vascular wall remodeling with aortic stenosis, cardiomegaly, impaired limb and tail circulation, fatty tissue loss and systemic amyloid deposition in multiple organs with liver and kidney dysfunction in mouse models with severe dermatitis caused by persistent release of IL-1s from the skin. These morbid conditions were ameliorated by simultaneous administration of anti-IL-1α and IL-1β antibodies. These findings may explain the morbid association of arteriosclerosis, heart involvement, amyloidosis and cachexia in severe systemic skin diseases and systemic autoinflammatory diseases, and support the value of anti-IL-1 therapy for systemic inflammatory diseases.     

Simulation of forest carbon dynamics based on a dry-matter production model

A microcomputer model for forest carbon dynamics with five functional comparments (atmosphere, foliage, woody-parts, roots and dead biomass in the soil) is constructed which incorporates dry-matter production processes of trees such as photosynthesis, respiration and allocation of photosynthate. The effect of photosynthesis rate at saturated light and dark respiration rate of a single leaf upon surplus production (P _s) is three-dimensionally illustrated as a function of cumulative leaf area index (LAI) and extinction coefficient of light. Probable values of the physiological parameters in this model are determined by repeated simulation experiments. The successional pattern during a period of 100 years is simulated, demonstrating stable and perpetual occurrence of a tropical rainforest ecosystem composed of three strata. The model is also analyzed in terms of response of relative initial density of trees, thereby displaying the law of constant final yield in a forest ecosystem. The model outputs of carbon fluxes and phytomasses at the steady state agree quite well with field data already obtained from a tropical rainforest at Pasoh.     

Discovery of evocalcet,a next-generation calcium-sensing receptor agonist for the treatment of hyperparathyroidism

The calcium-sensing receptor (CaSR) plays an important role in sensing extracellular calcium ions and regulating parathyroid hormone secretion by parathyroid gland cells, and the receptor is a suitable target for the treatment of hyperparathyroidism. Cinacalcet hydrochloride is a representative CaSR agonist which widely used for the hyperparathyroidism. However, it has several issues to clinical use, such as nausea/vomiting and strong inhibition of CYP2D6. We tried to improve these issues of cinacalcet for a new pharmaceutical agent as a preferable CaSR agonist. Optimization from cinacalcet resulted in the identification of pyrrolidine compounds and successfully led to the discovery of evocalcet as an oral allosteric CaSR agonist. Evocalcet, which exhibited highly favorable profiles such as CaSR agonistic activity and good DMPK profiles, will provide a novel therapeutic option for secondary hyperparathyroidism.     

Proliferation, differentiation and morphogenesis of fetal rat glandular stomach transplanted under the kidney capsule of syngeneic hosts

Undifferentiated glandular stomach tissue fragments from 16.5-day fetal rats were transplanted under the kidney capsule of syngeneic adult rats, and the proliferation, differentiation and morphogenesis of the transplanted tissues were investigated. Gastric epithelial cells began to invaginate 3–4 days after the transplantation and immature glands were formed after 1 week. During the period, there was a gradual increase in the expression of pepsinogen and cathepsin E, markers of cytodifferentiation of the stomach epithelia, both at protein and mRNA levels. Cathepsin E was weakly expressed in undifferentiated gastric epithelial cells at 16.5 days of gestation, and a higher level of the expression was observed in differentiated epithelia of the transplants. In contrast, the pepsinogen-producing cells first appeared around days 3–4 after transplantation and gradually increased in number to about 30% of the epithelial cells and became localized at the bottom of the gland. During the period of the experiment up to 1 month, the pepsinogen-producing cells were all positive for class III mucin and cathepsin E, indicating the immature character of these cells. In addition, no parietal cells were observed. When the tissue fragments were transplanted into adrenalectomized animals, the epithelial differentiation and morphogenesis was suppressed, but its proliferation was enhanced. The observed changes were reversed by hydrocortisone replacement. These results suggest that the development of the 16.5-day fetal stomach is regulated intrinsically to a certain extent by the genetic program of the cells involved and various gastric functions develop in the absence of luminal stimulation, stage-specific systemic hormonal change, neuronal regulation or other systemic influences, and that glucocorticoids modulate the developmental program of the fetal stomach tissues.     

The rapid spread of recombinants during a natural in vitro infection with two human immunodeficiency virus type 1 strains.

We quantified a population of recombinants in a natural in vitro infection, using wild-type viruses without any pressure. It was found that recombinants emerged early after infection and constituted more than 20% of the whole proviral population 15 days after infection. Furthermore, recombinants were isolated as infectious viruses by simple limiting dilution. These results imply that, in addition to the high mutation rate of human immunodeficiency virus type 1 (HIV-1), recombination among HIV-1 strains plays a significant part in the development of the high diversity of HIV-1.     

Sensitive analytical method for the novel H1-receptor antagonist HSR-609 in human plasma and urine by high-performance liquid chromatography with pre-column fluorescent derivatization

A simple and sensitive method for quantitation of HSR-609 (I) in human plasma and urine was developed using HPLC with the fluorescence labelling reagent 4-(N,N-dimethylaminosulfonyl)-7-N-piperazino-2,1,3-benzoxadiazole (DBD-PZ). Compound I was extracted from human plasma and urine, and derivatized by reaction with DBD-PZ in the presence of Mukaiyama reagent A, an equimolar solution of 2,2′-dipyridyl disulfide (DPDS) and triphenylphosphine (TPP) in acetonitrile. The reaction mixture was cleaned up by liquid-liquid extraction following the derivatization. The conjugate was analyzed by ion-pair HPLC with fluorometric detection. The quantitation limits for I were 0.5 ng/ml in plasma and 5 ng/ml in urine. Using this method, plasma concentration and urinary excretion of I were studied after oral administration of I to human volunteers.     

Simulation of forest carbon dynamics based on a dry-matter production model

Effects of dry season upon a tropical rainforest ecosystem are analysed by employing the microcomputer model developed in a previous paper (Oikawa, 1985). Surplus production (P _s) illustrated in a three-dimensional figure linearly decreases with the length of dry season (λ). Simulation experiments demonstrate that all the three strata constituting the tropical rainforest ecosystem model are able to exist stably and perpetually unless λ exceeds four months. However, it is suggested that the dry season lasting five months brings about a transition from a tropical rainforest to a subtropical deciduous forest, because the upper story fails in a stable and perpetual occurrence at λ =5 months. Though the total living phytomass gradually decreases with prolonged dry season within four months, supplementary increase of living phytomass is observed in the middle story. A considerable amount of soil organic dead accumulated is also observed with increasing dry season, so that fairly constant ecosystem biomass including soil organic dead is predicted independent of the length of dry season so long as it is less than five months.     

Pollination in Bruguiera gymnorrhiza (Rhizophoraceae) in Miyara River, Ishigaki Island, Japan, and Phangnga, Thailand

Abstract The bird species Hypsipetes amaurotis and Zosterops palpebrosa var. yonakuni , but no insects, were recorded regularly feeding on flower-nectar of Bruguiera gymnorrhiza in the Miyara River Biological Preserve, Ishigaki Island, Japan, at 7:00-9:15 a.m. during the investigation from December 20, 1987, to January 19, 1988. In contrast, Anthreptes malacensis foraged for nectar from 7:00 a.m. to 17:00 p.m. Oriolus chinensis visited the flowers mainly between 6:30 and 7:30 a.m. in Phangnga, Thailand, during the investigation from November 30 to December 19, 1986. Pollen grains were sprayed onto the birds'faces and bills and into the air. The highest mean volume of 0.24 pollen grains/ l /minute was triggered in calm air by the most frequent nectarivore between 6:45 and 7:00 a.m. at a height of 1.5m under a tree-branch carrying 145 fresh flowers in the Miyara River population, Japan. The highest mean volume of 0.27 pollen grains/ l /minute under the same conditions in the Phangnga population, Thailand. Bruguiera gymnorrhiza is bird-pollinated but with the possibility of some pollination indirectly by wind.