ABSTRACT
<p><b>OBJECTIVE</b>To assess biological response and health adverse effects of industrial dusts from pottery factories and tungsten mines on alveolar macrophages (AM) in vitro.</p><p><b>METHODS</b>AM acquired from bronchoalveolar lavage of guinea pigs were used as the target cells. AM were then co-cultured with respirable dust particles (15, 30, 60 and 120 μg/10⁶) from pottery factories and tungsten mines. LDH activity, cell viability, the release of ROS and TNF-α were determined to assess the biological responses of the dusts. China Standard Quartz was used as control.</p><p><b>RESULTS</b>Dose- response relationships between the dust concentrations and the enhancement of LDH activity, the release of ROS and TNF-α were found in both dusts from pottery factories and tungsten mines. The cell viability decreased when the dusts' concentrations increased. Differences of biological response were observed in the dust particles from different mines or factories. Compared with the pottery dusts, higher LDH activity and the release of TNF-α induced by tungsten dust were observed. In the 120 μg/10⁶ group, the TNF-α induced by tungsten dust, pottery dusts and China Standard Quartz was (5.2 +/- 2.0) ng/ml, (3.3 +/- 1.6) ng/ml and (2.8 +/- 0.5) ng/ml respectively. However, the impact on the cell viability induced by pottery dust was higher than that by tungsten mine.</p><p><b>CONCLUSION</b>Industrial dusts from various sources could induce different biological effects. The results of the biological effects of dusts in laboratory tests may be of potential use to provide base data for their adverse effects evaluation.</p>
Subject(s)
Animals , Cell Survival , Cells, Cultured , Ceramics , Dust , Guinea Pigs , Lactate Dehydrogenases , Metabolism , Macrophages, Alveolar , Metabolism , Mining , Quartz , Toxicity , Reactive Oxygen Species , Metabolism , Tumor Necrosis Factor-alpha , Metabolism , Tungsten , ToxicityABSTRACT
<p><b>OBJECTIVE</b>To assess the effects of the alteration of humidity and (or) temperature on weight of filters without and with ambient particulate matter in a balance room.</p><p><b>METHODS</b>The mass of blank dust sampling filters were weighed under (18 +/- 1) degrees C and (28 +/- 1) degrees C respectively, with the humidity varying from 35% relative humidity (RH) to 100% RH in a balance room. Then the blank filters were divided into two groups and were used to sample total dust and respirable dust. After sampling, the loaded filters were re-weighed under above conditions and the mass difference before and after the sampling were compared and analyzed.</p><p><b>RESULTS</b>The vibration of the average mass of filters varied from 0.10 to 0.13 mg and from 0.06 to 0.09 mg under the temperatures of (18 +/- 1) degrees C and (28 +/- 1) degrees C respectively; When both the temperature and humidity changed, it varied from 0.12 to 0.16 mg. The deviation of average mass difference ranged from 0.07 to 0.10 mg and from 0.04 to 0.08 mg under the two temperatures mentioned above; When both the temperature and humidity changed, it varied from 0.09 to 0.14 mg. The average mass of blank filters and loaded filters were all positively correlated with the change of humidity (P < 0.01). No effects of humidity on the average mass difference of the loaded filters were observed. The average mass differences of loaded filters and blank filters under (18 +/- 1) degrees C were significantly higher than that under (28 +/- 1) degrees C (P < 0.01) when humidity was not changed.</p><p><b>CONCLUSION</b>The alteration of humidity and (or) temperature in a balance room attributes to the deviation of the measurement of the mass of filters and thus affects the gravimetric measurements of ambient particulate matter.</p>
Subject(s)
Air Pollutants , Environmental Monitoring , Filtration , Humidity , Particulate Matter , TemperatureABSTRACT
In this study, plate transparent circle by Davis method was introduce firstly screening ?-Rhamnosidase high-yield strain. The spore-sprouted Aspergillus niger 8-hour were mutagenized by ethyl methane sulphonate and pre-screened via transparent circle. 11% mutants yield 40% higher of ?-rhamnosidase than the original strain. A high-yield strain, T-226 with the highest ?-rhamnosidase activity of 373.4 U/mL was finally selected from these potential high-yield mutants after rescreened by shake flask fermentation twice. When the T-226 strain was fermented in 5 L bioreactor, the enzyme activity could reach to 631.9 U/mL after 84 h. Thus, the established screening method is highly efficient to isolate ?-rhamnosidase high-yield mutant of A. niger.
ABSTRACT
In order to develop a rapid method which can check Campylobacter jejuni in animal and poultry foods nicely, an immunomagnetic capture-fluorescent PCR (IMC-FPCR) method was established in this paper. The reported method involves isolation of the target pathogen by immunocapture prior to the fluorescent PCR step, therefore the immunomagnetic-beads for Campylobacter were developed, and two groups of primer/probe, which targeted for the species special sequence of flaA gene and hipO gene for Campylobacter jejuni were designed. The immunomagnetic capture-fluorescent PCR assay amplification of the hipO gene and flaA gene for detection of Campylobacter jejuni was firstly reported in this paper. Result indicated that IMC-FPCR method permits direct detection of the pathogen without an enrichment step and can be performed in approximately 24 h. The assay results are positive for all of the isolates of Campylobacter jejuni (3 isolates, including type strain ATCC 33560 and ATCC8341) with a detection limit of approximately 10 cfu/mL, are negative for Campylobacter coli and several other bacteria. IMC-FPCR assay provide not only a rapid, sensitive method for quantitative detection of Campylobacter jejuni, but also an important method for detecting of Campylobacter jejuni of viable but non-culturerable (VNC) state.
Subject(s)
Campylobacter jejuni , Genetics , Fluorescence , Immunomagnetic Separation , Methods , Polymerase Chain Reaction , Methods , Sensitivity and SpecificityABSTRACT
One hundred and seventy-two strains of endophytic fungi were isolated from Taxus mairei,Cephalotaxus fortunei and Torreya grandis cv.merrillia.The result of the antifungal assay shows that ninety strains of the fungi have antagonism against one or more botanical pathogenic fungi,such as Neurospora sp.,Trichoderma sp.,Fusarium sp.etc.The percentage of antifungal strains to tested strains are as follows:40% Cephalotaxus fortunei,54.2% Taxus mairei,57.1% Torreya grandis cv.merrillia.Thirty-five strains have high antifungal activities,and their inhibition zone diameter is at least 15mm.The active endophytic fungi were identified as 18 genera,most of which belong to Paecilomyces and Fusarium etc.
ABSTRACT
This paper summarize the practice in the teaching reform of microbiology experiment in recent years. We identify the main contents of experimental teaching systems and pay much more attention to peo-ple-oriented. Through the reform of teaching and assessment methods,students are trained to cultivate their practical ability and spirit of innovation.
ABSTRACT
Mycoepoxydiene is a novel antitumor agent extracted from marine lignicolous fungi HLY-2, which is Diaporthe phaseolorum by molecule identification. The medium optimization for mycoepoxydiene by orthogonal design and the comparison of submerged fermentation and solid state fermentation were studied. The rusult is that the maximal yield of the compound is 543mg/L, which is 43 times compared to the customary half-seawater PD medium and 15 times to the best submerged condition. This optimum culture medium included potato 250g/L, seawater 300mL/L, glucose 30g/L, lactose 50g/L, KH_ 2 PO_ 4 0.65mmol/L and (NH_ 4 )_ 2 SO_ 4 1g/L in the solid state condition. Differentiation analysis between submerged and solid state fermentation, and antitumor activity of these ferment products were also studied. The antitumor activity of products of the optimum medium approached the pure compound.