Incidence of symptomatic vertebral fractures in women of childbearing age newly treated with high-dose glucocorticoid

Background: The treatment and prevention of glucocorticoid (GC)-induced osteoporosis have been controversial in premenopausal women during their childbearing years.Objective: This study assessed the incidence and risk factors for symptomatic vertebral fracture in women of childbearing age newly treated with high-dose GC.Methods: An observational cohort study was conducted at the rheumatic center of Shimoshizu National Hospital in Chiba, Japan, from 1986 to 2006. The prevalence of symptomatic vertebral fractures, as determined by x-rays, was assessed in premenopausal (aged <50 years) women with collagen vascular disease newly treated with high-dose GC (≥20 mg/d prednisolone equivalent) compared with their counterparts who did not receive GC. Differences in the incidences of vertebral fractures were compared between groups by the Kaplan-Meier method and evaluated by the log-rank test. Hazard ratios (HRs) with 95% CIs were estimated using the Cox proportional hazards regression model.Results: A total of 373 women were assessed: 292 patients in the high-dose GC treatment group (mean [SD] initial age, 32.4 [8.2] years; initial dose, 43.8 [14.9] mg/d; follow-up time, 124.2 [75.4] months) and 81 patients in the non-GC control group (initial age, 39.3 [7.8] years; follow-up time, 106.5 [79.7] months). Symptomatic vertebral fractures occurred more frequently in the high-dose GC group (11.3%) than in the non-GC group (1.2%). Using the Cox model, the adjusted HR for the high-dose GC group was 13.96 (95% CI, 1.87–104.22) relative to the non-GC group. In the high-dose GC group, Kaplan-Meier analyses revealed that the incidence of fractures in women in their forties was significantly higher in comparison with those in their twenties (P < 0.001) and thirties (P < 0.05), and that the incidence of fractures in those who consumed alcohol (>80 g/wk of pure alcohol) was significantly higher than in those who did not (P < 0.05). The Cox model also revealed that the risk was independently higher with every 10-year increment of initial age (HR = 2.27; 95% CI, 1.46–3.53), with every GC dose increase (HR = 2.28; 95% CI, 1.58–3.31), and with each 1-gram decrease of cumulative GC dose (HR = 0.95; 95% CI, 0.93–0.98).Conclusions: In this study, high-dose GC use was associated with a significantly high prevalence of symptomatic vertebral fractures in premenopausal women with collagen vascular disease during their childbearing years. However, the fracture risk was relatively low in women of childbearing age, especially those in their twenties and thirties during the early years of treatment.     

Effects of water content on the enantioselectivity of α-chymotrypsin catalysis in organic media

Summary The -chymotrypsin-catalyzed transesterification between N-trifluoroacetyl-DL-phenylalanine trifluoroethyl ester and 1-propanol was carried out in a variety of organic solvents. The addition of small quantities of water enhanced both the rate of reaction and enantioselectivity. A high enantioselectivity was achieved in ethyl acetate (E = 120), diethyl ether (86), or acetonitrile (60). The competing hydrolysis became significant at water content higher than 0.5% (w/w).     

Production of L-aspartic acid from fumaric acid by a fumaric acid-assimilating obligate thermophile,Bacillus stearothermophilus KP 1041

Summary A fumaric acid-assimilating obligate thermophile having a high aspartase activity was isolated from soil. The isolate (KP 1041) that grew at 45 to 68 °C was assigned to a strain of Bacillus stearothermophilus. The cell suspensions produced L-aspartate from fumarate and ammonium ion, with the rapidest initial rate at 65 °C and pH 9.5. The Michaelis constant for fumarate was 0.2 M. The cellular aspartase was relatively stable for 18 h at and below 50 °C over a pH range 6.7–8.3 in the presence of ammonium fumarate; this substance protected the enzyme from heat inactivation. The best yield in L-aspartic acid production was achieved at 6 h incubation at 53 °C and pH 8.5, using 0.88 M fumarate, 3.1 M ammonium ion, and the cells at 53 mg dry weight per ml. In this case, 85% of fumarate added was converted into aspartic acid. The structure of the product was determined from its infrared spectrum, specific rotation, melting point and ultimate analysis.Presented at the Annual Meeting of the Agricultural Chemical Society of Japan, Yokohama, April 2, 1977     

Analyses of absorption and fluorescence spectra of water-soluble chlorophyll proteins,pigment System II particles and chlorophyll a in diethylether solution by the curve-fitting method

Absorption and fluorescence spectra in the red region of water-soluble chlorophyll proteins, Lepidium CP661, CP663 and Brassica CP673, pigment System II particles of spinach chloroplasts and chlorophyll a in diethylether solution at 25°C were analyzed by the curve-fitting method (French, C.S., Brown, J.S. and Lawrence, M.C. (1972) Plant Physiol. 49, 421–429). It was found that each of the chlorophyll forms of the chlorophyll proteins and the pigment System II particles had a corresponding fluorescence band with the Stokes shift ranging from 0.6 to 4.0 nm.The absorption spectrum of chlorophyll a in diethylether solution was analyzed to one major band with a peak at 660.5 nm and some minor bands, while the fluorescence spectrum was analyzed to one major band with a peak at 664.9 nm and some minor bands. A mirror image was clearly demonstrated between the resolved spectra of absorption and fluorescence. The absorption spectrum of Lepidium CP661 was composed of a chlorophyll b form with a peak at 652.8 nm and two chlorophyll a forms with peaks at 662.6 and 671.9 nm. The fluorescence spectrum was analyzed to five component bands. Three of them with peaks at 654.8, 664.6 and 674.6 nm were attributed to emissions of the three chlorophyll forms with the Stokes shift of 2.0–2.7 nm. The absorption spectrum of Brassica CP673 had a chlorophyll b form with a peak at 653.7 nm and four chlorophyll a forms with peaks at 662.7, 671.3, 676.9 and 684.2 nm. The fluorescence spectrum was resolved into seven component bands. Four of them with peaks at 666.7, 673.1, 677.5 and 686.2 nm corresponded to the four chlorophyll a forms with the Stokes shift of 0.6–4.0 nm. The absorption spectrum of the pigment System II particles had a chlorophyll b form with a peak at 652.4 nm and three chlorophyll a forms with peaks at 662.9, 672.1 and 681.6 nm. The fluorescence spectrum was analyzed to four major component bands with peaks at 674.1, 682.8, 692.0 and 706.7 nm and some minor bands. The former two bands corresponded to the chlorophyll a forms with peaks at 672.1 and 681.6 nm with the Stokes shift of 2.0 and 1.2 nm, respectively.Absorption spectra at 25°C and at ?196°C of the water-soluble chlorophyll proteins were compared by the curve-fitting method. The component bands at ?196°C were blue-shifted by 0.8–4.1 nm and narrower in half widths as compared to those at 25°C.     

Functionally essential cytoplasmic domain of the erythropoietin receptor.

The cytoplasmic domains of the erythropoietin receptor essential for signal transduction were identified by assessing a series of truncated and deletional mutant receptors. A 91-amino acid region proximal to the transmembrane domain was required for growth signaling. In this region, residues between 353Pro and 362His and between 278Gln and 308Leu appeared to constitute the essential cytoplasmic domains. These two domains contain the conserved amino acids common in the cytokine receptor superfamily, which indicates that these domains in the cytoplasmic regions of the erythropoietin receptor may be important for interaction with common signal transducers or protein tyrosine kinases.     

OsRALyase1, a putative F-box protein identified in rice,Oryza sativa,with enzyme activity identical to that of wheat RALyase

A rice gene, OsRALyase1, encoding a product similar to wheat ribosomal RNA apurinic site specific lyase (RALyase), was isolated and expressed in vitro. An open reading frame of the gene predicted a protein of 476 amino acid residues with 75% identity to RALyase and contained an F-box-like motif in its amino terminal region. The rice gene product expressed in a wheat-germ protein expression system had the same characteristics as its wheat counterpart, cleaving a specific depurinated site of the 28S rRNA sarcin-ricin domain.     

Proposal of leukotoxin, 9,10-epoxy-12-octadecenoate, as a burn toxin

It is postulated that toxic substances (burn toxin) synthesized in burned skin are transferred into general circulation and cause multiple organ failure. We found a highly cytotoxic substance, leukotoxin, a linoleate epoxide, exists in burned skin. Leukotoxin, as the name indicates, was synthesized by leukocytes from linoleate as a substrate. The aim of this study is to evaluate the possibility of leukotoxin as a burn toxin. We studied plasma leukotoxin level of four patients with extensive burns (over 50% of body surface area) and examined coagulation studies in these patients. We detected considerable amounts of leukotoxin (11.4 nmol/ml-37.0 nmol/ml) in all patients. Leukotoxin was not detected in the control subjects. Pulmonary edema, cardiac failure, and coagulation abnormalities were found in these patients. Exogeneously administered leukotoxin induced similar pathological conditions in experimental animals to those observed in patients with extensive burns. Hence, it is concluded that leukotoxin is a responsible substance as a burn toxin.     

Hierarchical Chromatin Structure of <Emphasis Type="Italic">Schizosaccharomyces pombe</Emphasis> Revealed by Atomic Force Microscopy

Many structural studies on higher eukaryotic chromatin have been carried out, but chromatin structure in fungi remains unclear. Schizosaccharomyces pombe has been used for investigations of chromosome function; however, the structural details of S. pombe chromatin have not been clarified owing to its small nucleus. We used atomic force microscopy for nano-scale imaging of chromatin isolated from S. pombe. Topographic images indicated that nuclear chromatin contained at least three hierarchical structures: large-scale chromatin fibers, spherical domains in the fibers, and nodules in the domains. The average diameters of the domain and the nodule were 363 ± 85.2 nm and 46.2 ± 9.30 nm. Each structure comprising the hierarchy was similar to higher eukaryotic chromatin thus far observed, despite definite differences in chromatin organization at the nucleosomal level. The presence of histone H1 suggested that there might be an alternative to compensate for histone H1 lacking in S. pombe.