Structural analysis of mucoidan, an acidic extracellular polysaccharide produced by a pristane-assimilating marine bacterium, Rhodococcus erythropolis PR4

Rhodococcus erythropolis PR4 is a marine bacterium that can degrade various alkanes including pristane, a C(19) branched alkane. This strain produces a large quantity of extracellular polysaccharides (EPS), which are assumed to play an important role in the hydrocarbon tolerance of R. erythropolis PR4. The strain produced an acidic EPS, mucoidan, together with a fatty acid-containing EPS, PR4 FACEPS. The chemical structure of the mucoidan was determined using (1)H and (13)C NMR spectroscopy and by conducting 2D DQF-COSY, TOCSY, HMQC, HMBC, and NOESY experiments. The mucoidan was shown to consist of a pentasaccharide repeating unit with the following structure: [structure: see text].     

Venous thromboembolism after total joint arthroplasty: results from a Japanese multicenter cohort study

Introduction

Real-world evidence of the effectiveness of pharmacological thromboprophylaxis for venous thromboembolism (VTE) is limited. Our objective was to assess the effectiveness and safety of thromboprophylactic regimens in Japanese patients undergoing joint replacement in a real-world setting.

Method

Overall, 1,294 patients (1,073 females and 221 males) who underwent total knee arthroplasty (TKA) and 868 patients (740 females and 128 males) who underwent total hip arthroplasty (THA) in 34 Japanese national hospital organization (NHO) hospitals were enrolled. The primary efficacy outcome was the incidence of deep vein thrombosis (DVT) detected by mandatory bilateral ultrasonography up to post-operative day (POD) 10 and pulmonary embolism (PE) up to POD28. The main safety outcomes were bleeding (major or minor) and death from any cause up to POD28.

Results

Patients undergoing TKA (n = 1,294) received fondaparinux (n = 360), enoxaparin (n = 223), unfractionated heparin (n = 72), anti-platelet agents (n = 45), or no medication (n = 594). Patients undergoing THA (n = 868) received fondaparinux (n = 261), enoxaparin (n = 148), unfractionated heparin (n = 32), anti-platelet agents (n = 44), or no medication (n = 383). The incidence rates of sonographically diagnosed DVTs up to POD10 were 24.3% in patients undergoing TKA and 12.6% in patients undergoing THA, and the incidence rates of major bleeding up to POD28 were 1.2% and 2.3%, respectively. Neither fatal bleeding nor fatal pulmonary embolism occurred. Significant risk factors for postoperative VTE identified by multivariate analysis included gender (female) in both TKA and THA groups and use of a foot pump in the TKA group. Only prophylaxis with fondaparinux reduced the occurrence of VTE significantly in both groups. Propensity score matching analysis (fondaparinux versus enoxaparin) showed that the incidence of DVT was lower (relative risk 0.70, 95% confidence interval (CI) 0.58 to 0.85, P = 0.002 in TKA and relative risk 0.73, 95% CI 0.53 to 0.99, P = 0.134 in THA) but that the incidence of major bleeding was higher in the fondaparinux than in the enoxaparin group (3.4% versus 0.5%, P = 0.062 in TKA and 4.9% versus 0%, P = 0.022 in THA).

Conclusions

These findings indicate that prophylaxis with fondaparinux, not enoxaparin, reduces the risk of DVT but increases bleeding tendency in patients undergoing TKA and THA.

Trial registration

University Hospital Medical Information Network Clinical Trials Registry: UMIN000001366. Registered 11 September 2008.     

Dynamics of the history of photosynthesis research

A personal view of the history of progress in photosynthesis research beginning in the seventeenth century and ending in 1992 is presented in a chart form. The 350-year time span is divided arbitrarily into seven periods by the development junctures, which are likened to bamboo joints. The tempo of progress is reflected in the duration of the periods, starting from over 200 years for Period I, which progressively shortens in subsequent periods. This brief introduction highlights some of the events to show the dynamic nature of the progress in photosynthesis research.Professor emeritus of Okayama University, Okayama, Japan; correspondence address: Yokoi-kami, 507-66, Okayama City, Okayama, 701-11, Japan     

A new, light-induced absorbance change related to the reaction-center of photosystem II

A new, light-induced absorbance change centered at 591 nm wasfound during analysis of the effect of preliminary illuminationon ferricyanide photoreduction in spinach chloroplasts. Thisabsorbance change is believed to come from a chloroplast componentfunctionally related to the reaction-center of photosystem IIfor the following reasons: (1) It occurred rapidly upon illumination.(2) It was driven by only PS-II light. (3) It was observed evenat 77 K. (4) It was observed with subchloroplast preparationsenriched in the reaction-center of PS-II. (Received October 23, 1978; )     

A study on body temperature regulation and residential thermal environments of the elderly—I. whole country survey of residential thermal environment and evaluation methods: RTE-index

1. 1. As part of “research on environmental comfort,” that is, research which aims to make people's living environment more comfortable, we attempted to clarify the relation between the living environment of elderly people and physiological and psychological factors. We carried out a comprehensive study with a view to establishing comfort standards for the residential thermal environment, and for creating evaluation and control systems.

2. 2. The comfort of the living environment is closely related to the thermal environment and the temperature-regulation ability of the human body. This ability of the body to regulate temperature develops during childhood and recedes as the adult ages.

3. 3. We therefore carried out: (a) experiments on body-temperature regulation and on special characteristics of the body-temperature regulation of elderly people, (b) a nationwide survey of the actual residential thermal environments of elderly people and (c) a survey of the daily activities of elderly people, and how elderly people's physiological and psychological conditions change when they are engaged in these activities.

4. 4. As a result of these experiments and surveys, we were able to: (d) formulate standards for evaluation of the residential thermal environment and (e) numerically express the results of systematic evaluation of residential thermal environments of elderly people, by means of a RTE-index.

Interrelationships between two-dimensional phase diagrams and mean molecular area-mole fraction curves in mixed monolayers

Both two-dimensional phase diagrams and mean molecular area (A)—mole fraction(x₂^π) curves have been investigated for various types of mixed monolayer systems. Two-dimensional phase diagram analysis and the behavior of A−x₂^π curves were found to be in good agreement with each other. From this result it was concluded that we should consider both phase diagrams and A−x₂^π curves of a mixed monolayer system in order to understand the behavior of the A−x₂^π curves.     

Structural analysis of an extracellular polysaccharide produced by a benzene tolerant bacterium, Rhodococcus sp. 33

Rhodococcus sp. 33 can tolerate and efficiently degrade various concentrations of benzene, one of the most toxic and prevailing environmental pollutants. This strain produces a large quantity of extracellular polysaccharide (33 EPS), which plays an important role in the benzene tolerance in Rhodococcus sp. 33, especially by helping the cells to survive an initial challenge with benzene. This EPS has been reported to be composed of D-galactose, D-glucose, D-mannose, D-glucuronic acid, and pyruvic acid at a molar ratio of 1:1:1:1:1. To understand the protective effect of 33 EPS, we determined its chemical structure by using 1H and 13C NMR spectroscopy including 2D DQF-COSY, TOCSY, HMQC, HMBC, and NOESY experiments. The polysaccharide was shown to consist of tetrasaccharide repeating units with the following structure: [structure: see text].     

Oxime Ethers: New Potent Insect Growth Regulators

Oxime ethers containing a 4-phenoxyphenoxy group in the molecules were synthesized and their insect growth regulating (IGR) activities were studied. Of these new IGR’s, propionaldehyde oxime O-2-(4-phenoxyphenoxy)ethyl ether and propionaldehyde oxime O-2-(4-phenoxy-phenoxy)propyl ether were found to be most effective, having much higher activities than metho-prene against larvae of Culex pipiens pallens and Musca domestica by the immersion method and medium method, respectively. In addition, the effects of steric isomerism of these compounds were examined; their IGR activities were found to have a close relationship to the juvenile hor-mone activity by the Galleria wax test.