A case of chondrosarcoma in a free-flying Great Egret

A free-flying Great Egret (Ardea alba) captured in Gifu, central Japan, in May 2006 had a large mass on the right carpal joint. The tumor was diagnosed as chondrosarcoma by histopathologic examination.     

Phylogenetic analysis of bacteria preserved in a permafrost ice wedge for 25,000 years

Phylogenetic analysis of bacteria preserved within an ice wedge from the Fox permafrost tunnel was undertaken by cultivation and molecular techniques. The radiocarbon age of the ice wedge was determined. Our results suggest that the bacteria in the ice wedge adapted to the frozen conditions have survived for 25,000 years.     

Engineering of a type III rubisco from a hyperthermophilic archaeon in order to enhance catalytic performance in mesophilic host cells

The hyperthermophilic archaeon Thermococcus kodakaraensis harbors a type III ribulose 1,5-bisphosphate carboxylase/oxygenase (Rbc(Tk)). It has previously been shown that Rbc(Tk) is capable of supporting photoautotrophic and photoheterotrophic growth in a mesophilic host cell, Rhodopseudomonas palustris Delta3, whose three native Rubisco genes had been disrupted. Here, we have examined the enzymatic properties of Rbc(Tk) at 25 degrees C and have constructed mutant proteins in order to enhance its performance in mesophilic host cells. Initial sites for mutagenesis were selected by focusing on sequence differences in the loop 6 and alpha-helix 6 regions among Rbc(Tk) and the enzymes from spinach (mutant proteins SP1 to SP7), Galdieria partita (GP1 and GP2), and Rhodospirillum rubrum (RR1). Loop 6 of Rbc(Tk) is one residue longer than those found in the spinach and G. partita enzymes, and replacing Rbc(Tk) loop 6 with these regions led to dramatic decreases in activity. Six mutant enzymes retaining significant levels of Rubisco activity were selected, and their genes were introduced into R. palustris Delta3. Cells harboring mutant protein SP6 displayed a 31% increase in the specific growth rate under photoheterotrophic conditions compared to cells harboring wild-type Rbc(Tk). SP6 corresponds to a complete substitution of the original alpha-helix 6 of Rbc(Tk) with that of the spinach enzyme. Compared to wild-type Rbc(Tk), the purified SP6 mutant protein exhibited a 30% increase in turnover number (k(cat)) of the carboxylase activity and a 17% increase in the k(cat)/K(m) value. Based on these results, seven further mutant proteins were designed and examined. The results confirmed the importance of the length of loop 6 in Rbc(Tk) and also led to the identification of specific residue changes that resulted in an increase in the turnover number of Rbc(Tk) at ambient temperatures.     

Possible role of adrenomedullin in the regulation of Fontan circulation: mature form of plasma adrenomedullin is extracted in the lung in patients with Fontan procedure

OBJECTIVE: We investigated the pathophysiological significance of molecular forms of adrenomedullin (AM) in patients after the Fontan procedure. METHODS: Plasma concentrations of mature AM (AM-m), an active form, glycine-extended AM (AM-Gly), an inactive form, and total AM (AM-T: AM-m+AM-Gly) were measured by specific immunoradiometric assay in the femoral vein, pulmonary artery and femoral artery of 29 consecutive patients after the Fontan procedure. The eleven patients who had history of Kawasaki disease and have normal coronary and hemodynamics served as control. RESULTS: Patients who underwent Fontan procedure had significantly higher venous concentrations of AM-T, AM-Gly, and AM-m than age-matched normal controls (AM-T, 12.0+/-3.3 vs. 9.6+/-2.0; AM-Gly, 10.4+/-3.0 vs. 8.5+/-1.6; AM-m, 1.6+/-0.7 vs. 1.0+/-0.6 pmol/l, each p<0.05). In patients with Fontan procedure, there were no differences in plasma AM-T, AM-Gly or AM-m levels between the femoral vein and pulmonary artery, however, there was a significant step-down in the AM-m levels, but not in plasma AM-T or AM-Gly levels, between the pulmonary artery and femoral artery (1.3+/-0.6 to 1.0+/-0.6, p<0.05). The venous concentrations of AM-m correlated negatively with systemic blood flow (cardiac output) (r=-0.46, p<0.05). CONCLUSIONS: Results suggest that in Fontan circulation plasma AM-m is increased in parallel with those of AM-T and AM-Gly and that AM-m is extracted in the lung. Extracted AM-m may be involved in the regulation of pulmonary arterial tonus, although further studies are necessary to elucidate the exact role of AM in Fontan circulation.     

Fasudil attenuates sympathetic nervous activity in the adrenal medulla of spontaneously hypertensive rats

We investigated the effects of fasudil, a Rho kinase inhibitor, on hypertension in spontaneously hypertensive rats and on the catecholamine synthetic pathway. Ten-week-old male SHR and Wistar-Kyoto rats were administered fasudil (10 mg/kg/day s.c.) for 4 days. Systolic blood pressure was measured using the tail-cuff method. Catecholamine levels were measured with high-performance liquid chromatography-ECD methods. Tyrosine hydroxylase protein levels were measured in Western blot analysis. The tyrosine hydroxylase mRNA level was measured using real-time PCR methods. Fasudil significantly decreased systolic blood pressure in spontaneously hypertensive rats, but not in Wistar-Kyoto rats. Fasudil also significantly decreased catecholamine, tyrosine hydroxylase protein, and tyrosine hydroxylase mRNA levels in the adrenal medulla of spontaneously hypertensive rats. These results suggest that the depressor effects of fasudil on hypertension in spontaneously hypertensive rats may be related to inhibition of the catecholamine synthetic pathway.     

Biotransformation of raspberry ketone and zingerone by cultured cells of Phytolacca americana

The biotransformation of raspberry ketone and zingerone were individually investigated using cultured cells of Phytolacca americana. In addition to (2S)-4-(4-hydroxyphenyl)-2-butanol (2%), (2S)-4-(3,4-dihydroxyphenyl)-2-butanol (5%), 4-[4-(beta-d-glucopyranosyloxy)phenyl]-2-butanone (19%), 4-[(3S)-3-hydroxybutyl]phenyl-beta-d-glucopyranoside (23%), and (2S)-4-(4-hydroxyphenyl)but-2-yl-beta-d-glucopyranoside (20%), two biotransformation products, i.e., 2-hydroxy-4-[(3S)-3-hydroxybutyl]phenyl-beta-d-glucopyranoside (12%) and 2-hydroxy-5-[(3S)-3-hydroxybutyl]phenyl-beta-d-glucopyranoside (11%), were isolated from suspension cells after incubation with raspberry ketone for three days. On the other hand, two compounds, i.e., (2S)-4-(4-hydroxy-3-methoxyphenyl)but-2-yl-beta-d-glucopyranoside (17%) and (2S)-2-(beta-d-glucopyranosyloxy)-4-[4-(beta-d-glucopyranosyloxy)-3-methoxyphenyl]butane (16%), together with (2S)-4-(4-hydroxy-3-methoxyphenyl)-2-butanol (15%), 4-[4-(beta-d-glucopyranosyloxy)-3-methoxyphenyl]-2-butanone (21%), and 4-[(3S)-3-hydroxybutyl]-2-methoxyphenyl-beta-d-glucopyranoside (24%) were obtained upon addition of zingerone. Cultured cells of P. americana can reduce, and regioselectively hydroxylate and glucosylate, these food ingredients to their beta-glycosides.