Distribution and Solubilization of Particulate Gluconate Dehydrogenase and Particulate 2-Ketogluconate Dehydrogenase in Acetic Acid Bacteria

The distribution of two particulate enzymes, gluconate dehydrogenase (GDH) and 2-ketogluconate dehydrogenase (2KGDH), was investigated with cell free extract through 26 strains of genus Acetobacter and genus Gluconobacter. GDH activity was found in the cell free extracts from all strains of genus Gluconobacter and two species of genus Acetobacter, A. aceti and A. aurantium. High activity of 2KGDH was also found in the pigment-producing strains of genus Gluconobacter.

Best solubilization of particulate enzymes was attained with the highest recovery when 10 mg of Triton X–100 and 30 mg of protein of particulate fractions in 1 ml of 0.01 m phosphate buffer, pH 6.0, are incubated for 9 hr at 5°C with continuous stirring.

By comparison of the total enzyme activity of particulate enzymes with that of NAD(P)-linked enzymes in the cell free extract, it was obvious that the formation of ketogluconates by particulate enzymes was much more predominant, roughly over 100 times higher, as that of NAD(P)-linked enzymes.     

Attention to Eye Contact in the West and East: Autonomic Responses and Evaluative Ratings

Eye contact has a fundamental role in human social interaction. The special appearance of the human eye (i.e., white sclera contrasted with a coloured iris) implies the importance of detecting another person''s face through eye contact. Empirical studies have demonstrated that faces making eye contact are detected quickly and processed preferentially (i.e., the eye contact effect). Such sensitivity to eye contact seems to be innate and universal among humans; however, several studies suggest that cultural norms affect eye contact behaviours. For example, Japanese individuals exhibit less eye contact than do individuals from Western European or North American cultures. However, how culture modulates eye contact behaviour is unclear. The present study investigated cultural differences in autonomic correlates of attentional orienting (i.e., heart rate) and looking time. Additionally, we examined evaluative ratings of eye contact with another real person, displaying an emotionally neutral expression, between participants from Western European (Finnish) and East Asian (Japanese) cultures. Our results showed that eye contact elicited stronger heart rate deceleration responses (i.e., attentional orienting), shorter looking times, and higher ratings of subjective feelings of arousal as compared to averted gaze in both cultures. Instead, cultural differences in the eye contact effect were observed in various evaluative responses regarding the stimulus faces (e.g., facial emotion, approachability etc.). The rating results suggest that individuals from an East Asian culture perceive another''s face as being angrier, unapproachable, and unpleasant when making eye contact as compared to individuals from a Western European culture. The rating results also revealed that gaze direction (direct vs. averted) could influence perceptions about another person''s facial affect and disposition. These results suggest that cultural differences in eye contact behaviour emerge from differential display rules and cultural norms, as opposed to culture affecting eye contact behaviour directly at the physiological level.     

Descriptive Analysis of Patients’ EMS Use Related to Severity in Tokyo: A Population-Based Observational Study

Introduction

Few studies are available on the clinical characteristics of patients using emergency medical transports in Japan. In this study, we aimed to investigate reasons for emergency medical transports and their relation to clinical severity.

Methods

We conducted a 3-year population-based observational study of patients transported by ambulance to emergency departments (ED) in the capital of Japan, Tokyo, which has a population of about 13 million. Demographic data, reasons for transport, and the severity of initial assessment at ED were recorded. Logistic regression was used to determine the odds of the clinical severity of each reason for transport.

Results

The number of emergency medical transports in the three-year study period was 1,832,637. Mean age was 53±26. Males were 976,142 (53%). Overall, 92% of all transported patients were in a mild or moderate medical state and patients with the 17 most frequent reasons for transport occupied 82% (1,506,017) of all transports. Pain was the most frequent reason for transport, followed by traffic accident. Considering all the patients and their reasons for transport, patients whose reason was pain or a traffic accident (29% of all patients) were in a relatively mild state compared with patients with other reasons for transport. Patients in an altered mental state in the prehospital setting (6.8% of all patients) were in a more severe medical state than other patients.

Conclusions

In Tokyo, Japan, 92% of transported patients were in a mild or moderate medical state. In particular, most patients from traffic accidents were in a mild state, even though traffic accidents were the second most frequent reason for transport. Patients in an altered mental state were most likely to be in a severe medical state.     

Application of the backstepping method to the prediction of increase or decrease of infected population

Background

In mathematical epidemiology, age-structured epidemic models have usually been formulated as the boundary-value problems of the partial differential equations. On the other hand, in engineering, the backstepping method has recently been developed and widely studied by many authors.

Methods

Using the backstepping method, we obtained a boundary feedback control which plays the role of the threshold criteria for the prediction of increase or decrease of newly infected population. Under an assumption that the period of infectiousness is same for all infected individuals (that is, the recovery rate is given by the Dirac delta function multiplied by a sufficiently large positive constant), the prediction method is simplified to the comparison of the numbers of reported cases at the current and previous time steps.

Results

Our prediction method was applied to the reported cases per sentinel of influenza in Japan from 2006 to 2015 and its accuracy was 0.81 (404 correct predictions to the total 500 predictions). It was higher than that of the ARIMA models with different orders of the autoregressive part, differencing and moving-average process. In addition, a proposed method for the estimation of the number of reported cases, which is consistent with our prediction method, was better than that of the best-fitted ARIMA model ARIMA(1,1,0) in the sense of mean square error.

Conclusions

Our prediction method based on the backstepping method can be simplified to the comparison of the numbers of reported cases of the current and previous time steps. In spite of its simplicity, it can provide a good prediction for the spread of influenza in Japan.

     

Oxidative stress and delayed-onset muscle damage after exercise

Reactive oxygen species (ROS) produced during exercise may be involved in delayed-onset muscle damage related to inflammation. To investigate this hypothesis, we studied whether oxidative stress increases nuclear translocation of nuclear factor-kappaB and chemokine expression in skeletal muscle using myotube L6 cells. We also assessed whether prolonged acute exercise could increase these parameters in rats. In L6 cells, H(2)O(2) induced nuclear translocation of p65 and increased the expression of cytokine-induced neutrophil chemoattractant-1 (CINC-1) and monocyte chemoattractant protein-1 (MCP-1), whereas preincubation with alpha-tocopherol limited the increase in these proteins. Sprague Dawley rats were divided into the following groups: rested control, exercised, rested with a high alpha-tocopherol diet, and exercised with a high alpha-tocopherol diet. After 3 weeks of acclimation, both exercise groups ran on a treadmill at 25 m/min for 60 min. Exercise increased nuclear p65, CINC-1, and MCP-1 in gastrocnemius muscle cells, but these changes were ameliorated by the high alpha-tocopherol diet. Increases in myeloperoxidase and thiobarbituric acid-reactive substrates were ameliorated by a high alpha-tocopherol diet, as were the histological changes. Neutrophil activity was not altered by either exercise or a high alpha-tocopherol diet. These results indicate that delayed-onset muscle damage induced by prolonged exercise is partly related to inflammation via phagocyte infiltration caused by ROS and that alpha-tocopherol (an antioxidant) can attenuate such inflammatory changes.     

Tetrapetalone A, a novel lipoxygenase inhibitor from Streptomyces sp

A simple new assay was designed for lipoxygenase inhibitors. This assay was used to find the novel lipoxygenase inhibitor, tetrapetalone A (1). Tetrapetalone A (1), C26H33NO7, was isolated from Streptomyces sp. USF-4727 strain. Its planar structure was determined by spectroscopic evidence and by methylating with diazomethane to show the presence of a novel tetracyclic skeleton and a beta-D-rhodinosyl moiety. The stereochemistry of 1 was investigated by the coupling constant in the 1H-NMR spectrum, NOE correlations, modified Mosher's method and derivation. We have reported the structural elucidation of 1 in our previous paper. However, further investigation gave another structure for 1, which is described in this paper. Tetrapetalone A showed similar inhibitory activity against soybean lipoxygenase to the two well-known lipoxygenase inhibitors, kojic acid and NDGA, while methylated tetrapetalone A (2) showed little inhibitory activity, even at a concentration of 1 mM.     

Novel lipoxygenase inhibitors, tetrapetalone B, C, and D from Streptomyces sp

Three novel lipoxygenase inhibitors, tetrapetalone B (2, C(28)H(35)NO(9)), C (3, C(26)H(34)NO(8)), and D (4, C(28)H(36)NO(10)), were isolated from a culture broth of Streptomyces sp. USF-4727 that produced a lipoxygenase inhibitor tetrapetalone A (1) simultaneously. Each chemical structure was revealed by spectroscopic evidence, this suggests that these three compounds are structurally related to 1. They had a tetracyclic skeleton and a beta-D-rhodinosyl moiety. Tetrapetalone B, C, and D inhibited soybean lipoxygenase with IC(50): 320, 360, and 340 microM respectively.     

Induction of uPA release in human peripheral blood lymphocytes by [deamino-Cysl,D-Arg8]-vasopressin (dDAVP)

[deamino-Cys(l),d-Arg(8)]-vasopressin (dDAVP), known to be an arginine vasopressin (AVP) V(2) receptor agonist, is an agent that increases fibrinolytic activity levels in plasma after its infusion into the human body. However, mechanisms underlying an increase and exact localization of the extrarenal dDAVP-responsive V(2) receptor remain unclarified. Two AVP receptors, V(1a) and V(2), and a related oxytocin (OT) receptor were found to be expressed in human lymphocytes. Furthermore, we found an increase of fibrinolytic activity in the medium of peripheral lymphocytes obtained from human volunteers less than 20 min after dDAVP infusion. The increased activity was also detected in the medium after incubating the lymphocytes in the presence of dDAVP in vitro, being highest at 20 min after the incubation. In accord with the increased fibrinolytic activity, the levels of urokinase-type plasminogen activator (uPA) in the medium were also increased. However, there was no significant difference of plasminogen activator inhibitor-1 (PAI-1), pro-uPA, and tissue-type plasminogen activator (tPA) concentrations in the medium between dDAVP treatment and control. When lymphocytes were preincubated with a V(2) receptor antagonist [Adamantaneacetyl(1),O-Et-d-Tyr(2),Val(4),Aminobutyryl(6),Arg(8,9)]-vasopressin, the dDAVP-induced uPA increase was diminished. In contrast, preincubation with a V(1) receptor antagonist, [beta-Mercapto-beta,beta-cyclopentamethylenepropionyl(1),O-Me-Tyr(2),Arg(8)]-vasopressin, prior to dDAVP treatment resulted in a greater increase of the uPA concentration in the medium than with the dDAVP treatment alone. Thus it was suggested that dDAVP may induce uPA release from human lymphocytes via V(2) receptor-mediated reaction, and also via cross-talk between V(1) and V(2) receptors.     

Singlet oxygen quenching activity of human serum

Singlet oxygen is regarded as contributing to the pathogenesis of various diseases including light-induced skin disorders and inflammatory response. In this study, the correlation between singlet oxygen quenching activity (SOQA) of human serum and blood biochemistry or life-style was evaluated. Healthy volunteers were recruited and carried out a measurement of SOQA by using electron paramagnetic resonance (EPR) and a questionnaire survey about a smoking. It was demonstrated that major quenchers of singlet oxygen in serum are proteins, and small molecular anti-oxidants relatively play a minor role. SOQA of whole sera showed no correlation with protein concentration, but positively correlated with SOQA of small molecular fraction. In vitro studies demonstrated that the decrease of sulfhydryl groups by NO or superoxide significantly attenuated SOQA of albumin. Together, these results may imply that the underlying oxidative condition in each individual influences both small molecular antioxidant states and the sulfhydryl content of serum proteins. SOQA of sera from women with a smoking history was significantly lower compared to non-smoking women, suggesting that the smoking habit impaired the defense mechanism against singlet oxygen.