No abstract

Several lines of evidence suggest that micromere signaling plays a key role in endo-mesoderm differentiation along the animal-vegetal (A-V) axis in sea urchin embryos. A recent study has suggested that the activity of micromeres of inducing endoderm differentiation of mesomere descendants is, unexpectedly, maximal at the hatching blastula stage in the echinoids Scaphechinus mirabiris and Hemicentrotus pulcherrimus. In the present study, to confirm the inductive capacity of the micromere descendants in normal development, the timing of initiation of gastrulation and the elongation rate of the archenteron were examined in both micromereless embryos and in micromereless embryos cultured until the hatching blastula stage and then recombined with micromere descendants of the same age. The micromereless embryos consistently exhibited a delay in the initiation of gastrulation and a decrease in elongation rate of the archenteron, as compared with those in controls. In contrast, when the micromereless embryos cultured until the hatching blastula stage were recombined with micromere descendants of the same age, the recombinant embryos exhibited rescue of both the delay in initiation of gastrulation and a decrease in elongation rate of the archenteron. The delayed expression of alkaline phosphatase activity, an endoderm-specific marker, in the micromereless embryos was also rescued in the recombinant embryos. The recombined micromere descendants formed the larval spicules in the same schedule as that observed in the controls. These results indicate that at the hatching blastula stage, micromere descendants emanate a signal(s) required for normal gastrulation of the presumptive endo-mesodermal region.

Acute lower gastrointestinal bleeding is a rare complication of Crohn's disease (CD). Although anti-tumor necrosis factor-alpha (TNF-alpha, infliximab) therapy has been established for patients with inflammatory and fistulous CD, there has been little evidence on whether infliximab is effective for the hemorrhagic type of CD. We report a case of a 31-year-old man with CD who had recurrent sudden-onset bloody stool. After a second surgery, he visited our hospital because of bloody stool. Infusion of infliximab stopped the bleeding and promoted the healing of ulcers in the ileum and ileocolon anastomosis. We suggest that infliximab therapy should be tried to stop acute gastrointestinal bleeding in CD before there is a surgical emergency.

1. After a single oral dose of d-limonene (200-1200 mg/kg) no effects were observed on liver triglyceride, microsomal protein, cytochrome b5, and the drug-metabolizing enzymes. Glycogen content was slightly decreased at doses higher than 800 mg/kg, and cytochrome P-450 and delta-aminolaevulinic acid synthetase activity was slightly increased at 1200 mg/kg. 2. After repeated treatment (400 mg/kg/day) for 30 days, the relative liver weight and hepatic phospholipid content were only slightly increased, and liver and serum cholesterol were decreased 49 and 8%, respectively. Of the phospholipid fatty acids, palmitic, linoleic and arachidonic acids were increased, and stearic acid was decreased. Aminopyrine demethylase and aniline hydroxylase were increased 26 and 22%, respectively, and cytochrome P-450 and b5 were likewise increased 31 and 30%.