A Safety Influencing Factors Screening Method for Space Man-Machine System

Author(s):  
Lu Chen ◽  
Liming Ren ◽  
Xiaopeng Li ◽  
Fuqiu Li ◽  
Chunhui Wang ◽  
...  
Author(s):  
Ulrike Friedlein ◽  
Samart Dorn-In ◽  
Karin Schwaiger

The application of plant extracts (PEs) could be a promising option to satisfy consumers’ demand for natural additives to inhibit growth of variable pathogenic bacteria. Thus, the aim of this study was to develop a standardized microdilution method to examine the antimicrobial effects of ten hydrophilic plant extracts against two strains of C. perfringens facing various food-relevant influencing factors. Due to the high opacity of PEs, resazurin was used as an indicator for bacterial growth instead of pellet formation. The highest value of the minimum inhibitory concentration (MIC) of the replications of each PE was defined as effective plant extract concentration (EPC), whereas the next concentration beneath the lowest MIC value was defined as the ineffective plant extract concentration (IEPC). The EPC of seven PEs: allspice, cardamom, cinnamon, clove, coriander, ginger and mace were between 0.625 - 10 g/kg, whereas extracts of caravey, nutmeg and thyme showed no antimicrobial activity up to the maximum concentration tested (10 g/kg) against C. perfringens in vitro. Two intrinsic factors, sodium chloride and sodium nitrite, displayed either synergistic/additive effects or no interaction with most PEs. By combination with PEs at its ineffective plant concentration (IEPC, 0.08 – 1.25 g/kg), MIC of NaCl and NaNO2 decreased from 25 – 50 g/kg to 6 – 25 g/kg and > 200 mg/kg to 0.2 – 100 mg/kg respectively. On the contrary, lipid (sun flower oil) at a low concentration inhibited the antimicrobial effects of all tested PEs. For extrinsic factors, only allspice, ginger and coriander could maintain their antimicrobial effects after being heated to 78 °C for 30 min. The synergistic effect between PEs and pH values (5.0 and 5.5) was also found for all PEs. The established screening method with resazurin and defining EPC and IEPC values allows the verification of antimicrobial effects of PEs under various food-relevant influencing factors in a fast and reproducible way.


Author(s):  
David B. Warheit ◽  
Lena Achinko ◽  
Mark A. Hartsky

There is a great need for the development of a rapid and reliable bioassay to evaluate the pulmonary toxicity of inhaled particles. A number of methods have been proposed, including lung clearance studies, bronchoalveolar lavage analysis, and in vitro cytotoxicity tests. These methods are often limited in scope inasmuch as they measure only one dimension of the pulmonary response to inhaled, instilled or incubated dusts. Accordingly, a comprehensive approach to lung toxicity studies has been developed.To validate the method, rats were exposed for 6 hours or 3 days to various concentrations of either aerosolized alpha quartz silica (Si) or carbonyl iron (CI) particles. Cells and fluids from groups of sham and dust-exposed animals were recovered by bronchoalveolar lavage (BAL). Alkaline phosphatase, LDH and protein values were measured in BAL fluids at several time points postexposure. Cells were counted and evaluated for viability, as well as differential and cytochemical analysis. In addition, pulmonary macrophages (PM) were cultured and studied for morphology, chemotaxis, and phagocytosis by scanning electron microscopy.


2018 ◽  
Author(s):  
I Iozsef ◽  
O Ilyés ◽  
P Miheller ◽  
AV Patai
Keyword(s):  

1996 ◽  
Vol 75 (02) ◽  
pp. 242-245 ◽  
Author(s):  
Marie Magnusson ◽  
Bengt I Eriksson ◽  
Peter Kãlebo ◽  
Ramon Sivertsson

SummaryPatients undergoing orthopedic surgery are at high risk of developing deep vein thrombosis. One hundred and thirty-eight consecutive patients undergoing total hip replacement or hip fracture surgery were included in this study. They were surveilled with colour Doppler ultrasound (CDU) and bilateral ascending contrast phlebography. The prevalence of proximal and distal DVT in this study was 5.8% and 20.3% respectively.CDU has a satisfactory sensitivity in patients with symptomatic deep vein thrombosis, especially in the proximal region. These results could not be confirmed in the present study of asymptomatic patients. The sensitivity was 62.5% (95% confidence interval: C.I. 24-91%) and the specificity 99.6% (C.I. 98-100%) for proximal DVT; 53.6% (C.I. 34-73%) and 98% (C.I. 96-99%) respectively for distal thrombi. The overall sensitivity was 58.1% (C.I. 39-75%) and the specificity 98% (C.I. 96-99%). The positive predictive value was 83.3% (C.I. 36-99%) and 75% (C.I. 51-91%) for proximal and distal DVT respectively. The negative predictive value was 98.9% (C.I. 98-100%) and 94.9% (C.I. 92-98%) for proximal and distal DVT respectively. The results of this study showed that even with a highly specialised and experienced investigator the sensitivity of CDU was too low to make it suitable for screening purposes in a high risk surgical population.


1984 ◽  
Vol 52 (02) ◽  
pp. 172-175 ◽  
Author(s):  
P R Kelsey ◽  
K J Stevenson ◽  
L Poller

SummaryLiposomes of pure phospholipids were used in a modified APTT test system and the role of phosphatidyl serine (PS) in determining the sensitivity of the test system to the presence of lupus anticoagulants was assessed. Six consecutive patients with lupus anticoagulants and seven haemophiliacs with anticoagulants directed at specific coagulation factors, were studied. Increasing the concentration of phospholipid in the test system markedly reduced the sensitivity to lupus anticoagulants but had marginal effect on the specific factor inhibitors. The same effect was achieved when the content of PS alone was increased in a vehicle liposome of constant composition.The results suggest that the lupus anticoagulants can best be detected by a screening method using an APTT test with a reagent of low PS content. The use of a reagent rich in PS will largely abolish the lupus anticoagulant’s effect on the APTT. An approach using the two different types of reagent may facilitate differentiation of lupus inhibitors from other types of anticoagulant.


Skull Base ◽  
2007 ◽  
Vol 17 (S 1) ◽  
Author(s):  
Cem Meco ◽  
Gerhard Oberacher ◽  
Erich Arrer

CICTP 2017 ◽  
2018 ◽  
Author(s):  
Bowen Dong ◽  
Wenjun Du ◽  
Feng Chen ◽  
Qi Deng ◽  
Xiaodong Pan
Keyword(s):  

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