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1.
This work studies the ozonation of the pharmaceutical propranolol (PRO) in aqueous solution. Experimental results demonstrated that ozonation was an efficient method to remove PRO, achieving its complete abatement after 8?min of treatment (ozone dose of 0.47??mmol?L-1), starting from a PRO initial concentration of 0.38??mmol?L-1. The total organic carbon (TOC) analysis indicated that 1?h of ozonation (ozone dose of 3.54??mmol?L-1) was able to achieve only about 5% of the total organic carbon removal. The ozonation of PRO aqueous solutions has not promoted a prompt increase of the ratio of biological oxygen demand to chemical oxygen demand, thus indicating the need for higher ozone doses to initiate the biodegradability enhancement. The acute toxicity increased in the first minutes of reaction with a posterior reduction to values slightly higher than the toxicity of the PRO raw solution. Some early intermediate structures were proposed, and finally, kinetic constants for the direct attack of ozone on PRO structure were calculated. These values are in the order of magnitude of 105??L?mol-1?s-1.  相似文献   

2.
An Escherichia coli K 12 strain has been constructed for efficient expression of recombinant biologically active human IL-8 (Interleukin-8). The development of a fermentation and purification process from the laboratory scale (cells from 15 l fermentation broth) to a production scale (cells from 200 l fermentation broth) is described. Material obtained from the laboratory scale was used for initial in vitro studies and for the development of a biological assay. An upscale purification process starting from 80 l fermentation broth resulted in larger amounts of IL-8 needed for preclinical studies. This process includes a fully automated control of the initial affinity chromatography step. Finally, a production process which differed markedly from the small-scale processes was tailor-made for GMP conformity and economic considerations. It consists of a cell disruption step followed by two crossflow diafiltrations with different molecular weight cut offs and filtration rates, one cation exchange chromatography and a final dialysis step. In order to enhance the overall yield of biologically active IL-8, conditions for a resolubilisation of insoluble IL-8 present in the remaining pellet after cell disruption were worked out.  相似文献   

3.
The investigation of building products in test chambers contains so far only analytical and sensory measurements. In this paper, first experiments for the direct testing of the acute toxicity of building product emissions with the bioluminescence inhibition test are presented. The test specimen was a solvent-free dispersion paste for gluing carpets. Two tests with different air change rates were performed in a 1 m3 stainless steel test chamber. The emissions were concentrated at uniform timesteps in impinger-bottles and measured with the bioluminescence inhibition test. At the same time the concentrations of the emissions in the test chamber were measured both with charcoal adsorbent tubes (carbon disulphide desorption) and with tenax tubes (thermal desorption). The results of the bioluminescence inhibition test show, that the decrease of the toxicity over a period of 28 days is far lower at a low air change rate than at a higher air change rate. We also found, that from the multitude of the emitted substances the toxicity for the luminescence bacteria was only caused by Ethanol-[2-(2-butoxyethoxy)]-acetate.  相似文献   

4.
The data obtained of the acute and chronic toxicity of a number of staphylococcal immune preparations are presented. The paw edema test has been shown to yield more informative results for the evaluation of acute toxicity than the method of intraperitoneal injection and LD50 determination. The paw edema test has revealed that the toxicity of corpuscular vaccine is higher than that of the preparations of water-soluble antigenic staphylococcal complexes. The chronic toxicity test has demonstrated that corpuscular vaccine, antiphagin, adsorbed toxoid and the antigenic complex have low toxicity: their multiple administration in doses exceeding the equivalent doses 30-200 times have been found to exert no influence on the increase of the weight of the animals.  相似文献   

5.
INTRODUCTION: Tacrolimus (FK 506), a potent anti-T cell agent, has been shown to be effective in preventing the rejection of transplanted organs. Published research on tacrolimus has focused on effects associated with therapeutic use. Virtually no literature addresses the acute toxicity or the management of tacrolimus overdose. We report five cases of acute overdose with tacrolimus. CASE REPORTS: A 2-year-old female with no prior medical history ingested 10 mg of tacrolimus. She remained asymptomatic. A 2-year-old female with a history of multiple visceral organ transplants ingested 11 mg of her tacrolimus. She was admitted to the hospital and activated charcoal was administered. Her renal function was monitored and no changes were noted in a 24 h period. She was discharged. A 29-year-old male renal transplant patient took 150 mg of tacrolimus. He recovered with only a minimal creatinine elevation. A 23-year-old heart and lung transplant patient ingested 375 mg of tacrolimus. She had no effects from the overdose. A 34-year-old female experienced an acute/chronic overdose of 7-9 mg and remained asymptomatic. DISCUSSION: Tacrolimus is a neutral macrolide antibiotic that is extracted from the fermentation broth of the soil fungus Streptomyces tsukubaensis. Chronic oral dosing has been associated with numerous side effects. Although these patients ingested significant doses of tacrolimus, they suffered few toxic manifestations associated with tacrolimus. CONCLUSION: Little information is available regarding acute tacrolimus overdosage. In this small series of patients, tacrolimus did not produce acute physiologic incapacitation.  相似文献   

6.
Radiology of skeletal tuberculosis   总被引:1,自引:0,他引:1  
The process of hepatic fibrosis, and the changes in contents of hepatic hyproxyproline (HYP) and serum procollagen type III peptide (PIIINP) were examined in two rat models for hepatic fibrosis, i.e. bile duct ligation/scission (BDL/s)- and dimethylnitrosamine (DMN)-induced models. In addition, an expression of type III collagen mRNA in the liver of BDL/s model was also examined. In BDL/s model, hepatic fibrosis started at 2 weeks after operation (WAO) and cirrhosis with prominent bile duct hyperplasia was detected at and after 5 WAO. Serum PIIINP content measured using a modified double armed inhibition enzyme-linked immunosorbent assay (ELISA) method proposed by us started to increase at 1 WAO and continued to increase thereafter. Hepatic HYP content measured colorimetrically started to increase at 3 WAO and it continued to increase until 7 WAO. An expression of type III collagen mRNA in the liver was enhanced at and after 2 WAO, especially at 4 and 5 WAO. In DMN model, marked hepatic fibrosis was detected at 1 week after the last DMN administration (WAA), and the degree of fibrosis was apparently reduced at 4 WAA. Serum PIIINP content prominently increased at 1 WAA and decreased at and after 3 WAA. Hepatic HYP content showed a marked increase at 1 WAA and decreased thereafter. The present results indicated that the sequences of hepatic fibrosis, hepatic HYP content and serum PIIINP content were well correlated with each other in both BDL/s and DMN models. In conclusion, ELISA system for the detection of serum PIINP content is considered to be reliable method for assessment of cirrhotic liver, and the present two rat models for liver fibrosis/cirrhosis seems to be a good tool for researching antifibrotic agents.  相似文献   

7.
One hundred and seventy children with cough were divied into two groups at random. 120 patient were treated with Zhenkeling oral liquor (ZKL group). The other 50 children were given pectoral syrup (control group). The results showed that the total effective rates of ZKL group and control group were 96.7% and 56.0% respectively, and the markedly effective rates were 80.8%, 18.0% respectively (P < 0.001). Animal experiments indicated Zhenkeling has the effect of relieving cough, reducing sputum and ameliorating asthma; their antibiotic and anti-inflammatory effects were discovered too. The dosage of Zhenkeling was 100 times as clinical dose in acute toxicity test and the dosage was 32, 16, 8 times as clinical dose in long term toxicity test respectively. No adverse action was found in these experiments.  相似文献   

8.
Nocardicin A is a new monocyclic beta-lactam antibiotic obtained from the fermentation broth of a strain of actinomycetes. The producing organism, strain WS 1571, was identified as Nocardia uniformis subsp. tsuyamanensis ATCC 21806. The antibiotic, obtained as colorless crystals, exhibits moderate in vitro antibacterial activity against a broad-spectrum of Gram-negative bacteria including Proteus and Pseudomonas. It has low toxicity in laboratory animals.  相似文献   

9.
An integrated technique containing coagulation, ultraviolet/Fenton oxidation, and pressurized biological processes was provided for the treatment of wastewater generated from drilling operation where sulfonated muds were used. Ultraviolet/Fenton oxidation process was used to improve biodegradability of effluent after coagulation [assessed through a ratio of biological oxygen demand to chemical oxygen demand (COD) (B/C) index]. Pressurized biological experiments were used to further remove COD so as to meet the wastewater discharge standard. The results showed that coagulation pretreatment could help remove most of CODs (70–80%) in drilling wastewater. A 57% reduction in COD was obtained in the ultraviolet/Fenton oxidation process with 0.8 Qth H2O2 (in 30 min), and the biodegradability was significantly improved (B/C was increased from 0.03 to 0.47). The pressurized biological process could help speed up the reaction process with a saved aeration time of 66.7% under a system pressure of 0.2 MPa (in comparison with the condition of a normal pressure). The overall COD removal efficiency was about 95% and the COD level in the final effluent was less than 100 mg/L, which satisfied the wastewater discharge standard.  相似文献   

10.
Anaerobic and aerobic treatment of high-strength pharmaceutical wastewater was evaluated in this study. A batch test was performed to study the biodegradability of the wastewater, and the result indicated that a combination anaerobic-aerobic treatment system was effective in removing organic matter from the high-strength pharmaceutical wastewater. Based on the batch test, a pilot-scale system composed of an anaerobic baffled reactor followed by a biofilm airlift suspension reactor was designed. At a stable operational period, effluent chemical oxygen demand (COD) from the anaerobic baffled reactor ranged from 1,432 to 2,397?mg/L at a hydraulic retention time (HRT) of 1.25 day, and 979 to 1,749?mg/L at an HRT of 2.5 day, respectively, when influent COD ranged from 9,736 to 19,862?mg/L. As a result, effluent COD of the biofilm airlift suspension reactor varied between 256 and 355?mg/L at HRTs of from 5.0 to 12.5 h. The antibiotics ampicillin and aureomycin, with influent concentrations of 3.2 and 1.0?mg/L, respectively, could be partially degraded in the anaerobic baffled reactor: ampicillin and aureomycin removal efficiencies were 16.4 and 25.9% with an HRT of 1.25 day, and 42.1 and 31.3% with HRT of 2.5 day, respectively. Although effective in COD removal, the biofilm airlift suspension reactor did not display significant antibiotic removal, and the removal efficiencies of the two antibiotics were less than 10%.  相似文献   

11.
The effect of ozonation on the biodegradability of 100-ppm aqueous solutions of 2,4-dichlorophenol has been investigated. BOD at 5, 10 and 21 days, BOD/COD and BOD/TOC ratios and the average oxidation state are presented. Biodegradability measured as BOD5/COD ratio was increased from 0 of the original solution to 0.25 at the moment of removing all the initial compound (corresponding to an ozone dose of 0.12 g L-1, 0.48 for BOD21/COD ratio). To test the effect of this pre-treatment, the biological oxidation of these pre-ozonated solutions was performed in two semi-continuous stirred tank reactors, one with non-acclimated sludge and one with acclimated-to-phenol sludge. The study showed that the TOC content of the pre-treated solution could be removed up to 68% by an aerobic biological treatment as well as co-digested with municipal wastewater (TOC removal up to 82%), with similar operating retention times to a municipal wastewater plant (12-24 h). Kinetic studies based on Monod model have also been carried out. Pseudo-first-order kinetic constants were found to be in the range of 0.5-0.8 L g TVSS-1 h-1.  相似文献   

12.
Two new types of macrolide antibiotics, YM-32890 A and B, have been isolated from the fermentation broth of cytophaga sp. YL-02905S. In this paper, the taxonomy of the producing strain, fermentation, isolation, structure elucidation, and biological activity of the antibiotics are reported. YM-32890 A inhibits the growth of staphylococci including a macrolide-resistant strain, but shows no antimicrobial activity against other Gram-positive, Gram-negative bacteria and yeast.  相似文献   

13.
Asukamycin, a new antibiotic, has been isolated from the culture broth of a streptomycete designated as Streptomyces nodosus subsp. asukaensis. The antibiotic inhibits the growth of Gram-positive bacteria including Nocardia asteroides. The empirical formula of antibiotic asukamycin has been proposed as C29H22N2O9 (M.W. 542). An acute toxicity of the antibiotic in mice is LD50 48.5 mg/kg by intraperitoneal injection and it has no effect on mice when it was administered by 450 mg/kg per os.  相似文献   

14.
A Toxicity Reduction Evaluation (TRE) was conducted on the oily wastewater treatment plant (Plant) at a Naval Fuel Depot. The Plant treats ship and ballast wastes, berm water from fuel storage areas and wastes generated in the fuel reclamation plant utilizing physical/chemical treatment processes. In the first period of the project (Period I), the TRE included chemical characterization of the plant wastewaters, monitoring the final effluent for acute toxicity and a thorough evaluation of each treatment process and Plant operating procedures. Toxicity Identification Evaluation (TIE) procedures were performed as part of the overall TRE to characterize and identify possible sources of toxicity. Several difficulties were encountered because the effluent was saline, test organisms were marine species and toxicity was sporadic and unpredictable. The treatability approach utilizing enhancements, improved housekeeping, and operational changes produced substantial reductions in the acute toxicity of the final effluent. In the second period (Period II), additional acute toxicity testing and chemical characterization were performed through the Plant to assess the long-term effects of major unit process improvements for the removal of toxicity. The TIE procedures were also modified for saline wastewaters to focus on suspected class of toxicants such as surfactants. The TRE was successful in reducing acute toxicity of the final effluent through process improvements and operational modifications. The results indicated that the cause of toxicity was most likely due to combination of pollutants (matrix effect) rather than a single pollutant.  相似文献   

15.
A culture medium, named olive juice broth, which resembles the natural environment of Lactobacillus plantarum in the traditional Spanish-style green olive fermentation was obtained from green olives. In this medium, the bacteriocin-producing L. plantarum LPCO10 strain was able to produce bacteriocin throughout the incubation time (15 days). Bacteriocin purification from olive juice broth was achieved by a protocol including ammonium sulphate precipitation of cell-free, L. plantarum LPCO10 culture supernatants, and cation-exchange, hydrophobic-interaction and reversed-phase chromatographies. In a series of mixed cultures in olive juice broth, L. plantarum LPCO10 was able to dominate the bacteriocin-sensitive L. plantarum 128/2 strain, whereas the non-bacteriocin-producing, LPCO10 strain derivative, L. plantarum 55-1 strain did not show such capability. These results indicated that olive juice broth may be a valuable experimental substitute for olive fermentation brine in gaining more knowledge about the role of the bacteriocin-producing L. plantarum strains in the control of the Spanish-style green olive fermentation.  相似文献   

16.
Treatment of lead-contaminated material focuses on the reduction of leached lead concentrations in laboratory leaching tests. There has been little study on the chemical stability of treated materials after waste disposal. To investigate the effects of weathering on several solidification/stabilization chemistries, lead-contaminated soil was treated with various agents (cement, phosphates, dithiocarbamate, calcium hydroxide, calcium carbonate, and metallic iron) and subjected to natural weathering for one year. Lead concentrations and pH values in field percolates and leachates from toxicity characteristic leaching procedure (TCLP) and water leaching tests were used to evaluate changes in the treatment effectiveness. Weathering altered the treatment chemistry of several additives—alkaline additives were neutralized, while reduced additives were oxidized. Lead concentrations in field percolates from the untreated soil were around 1.0?mg/L, and did not vary over one year of weathering time. After one year of weathering, lead concentrations in field percolates from most samples were reduced to low levels (<0.15 mg/L). Weathering also affected lead concentrations in the TCLP and water leach test leachates from the treated wastes. Treated wastes in which the alkaline additives were neutralized or reduced additives oxidized gave higher TCLP lead concentrations after weathering than before, in contrast to the decreasing lead concentrations in the field percolates. Water leaching tests on the alkaline treated wastes had lower lead concentrations after weathering than before.  相似文献   

17.
A new antifungal antibiotic was isolated from the fermentation broth of Streptomyces sp. 5140-A1. Degradation studies of the crystalline antibiotic, m.p. 186 approximately 188 degrees C, C21H28O8N2, suggested Piricularia oryzae and less toxicity against killfish than antimycin A--blastmycin antibiotics.  相似文献   

18.
Peptostreptococcus anaerobius strain VPI 4330-1 was used as the test organism in an evaluation of the bactericidal effect of anaerobic broth exposed to air. The test organism, grown under anaerobic conditions in Trypticase soy broth, was diluted in buffered salt solution, and about 2 x 10(4) cells were suspended in 10 ml of an aerated broth. Ninety percent of the cells were killed within 15 min in actinomyces broth and within 50 min in Trypticase soy broth. All cells survived for 2 h in fluid thioglycolate medium. Addition of DABCO [1,4-diazabicyclo (2.2.2) octane] or mannitol to Trypticase soy broth did not influence the death rate of the organism, whereas superoxide dismutase decreased the death rate. Addition of catalase or manganese dioxide to the broth kept all the cells viable for 2 h. Of the three broth media tested, actinomyces broth reduced oxygen at the highest rate and Trypticase soy broth reduced it at the slowest rate. Hydrogen peroxide could be demonstrated in actinomyces broth and in Trypticase soy broth but not in fluid thioglycolate medium. In addition to catalase, manganese dioxide also removed all hydrogen peroxide from Trypticase soy broth, and superoxide dismutase significantly decreased the concentration of hydrogen peroxide in the broth. The results suggest that hydrogen peroxide mediated the toxic effect of atmospheric oxygen in these broth media.  相似文献   

19.
A collaborative study was performed in 18 laboratories to validate use of Rappaport-Vassiliadis (RV) medium in the standard culture method for recovery of Salmonella spp. from raw, highly contaminated foods and poultry feed. RV medium made from its individual ingredients and incubated at 42 degrees C was compared with selenite cystine (SC) broth incubated at 35 degrees C and tetrathionate (TT) broth incubated at 35 degrees and 43 degrees C for effectiveness in recovery of Salmonella spp. Four artificially contaminated foods (oysters, frog legs, mushrooms, and shrimp) and poultry feed and one naturally contaminated food (chicken) were analyzed. The artificially contaminated foods were inoculated with single serovars of Salmonella at target levels of 0.04 colony-forming units (CFU)/g for the low level and 0.4 CFU/g for the high level. For analysis of 1125 test portions, RV medium (42 degrees C) recovered Salmonella from 409 test portions; TT (43 degrees C), from 368 test portions; TT (35 degrees C), from 310 test portions; and SC (35 degrees C), from 334 test portions. Overall, RV medium was comparable with or better than other selective enrichments for recovery of Salmonella from the foods in this study, except mushrooms. From mushrooms, SC broth (35 degrees C) recovered more positive test portions than did RV medium (42 degrees C) and TT broth (43 degrees C). The method for detection of Salmonella in raw, highly contaminated foods and poultry feed using RV medium has been adopted by AOAC INTERNATIONAL. AOAC Official Method 967.25, Salmonella in Foods, Preparation of Culture Media and Reagents, has been revised to include RV medium, and the applicability of AOAC Official Method 967.26, Salmonella in Foods, Detection, has been restricted to processed foods.  相似文献   

20.
作为一种环境友好的冶金技术,难处理金矿的生物预氧化工艺已经在世界各地得到了推广应用,但是生物预氧化过程中释放出的三价砷会对细菌造成伤害,导致细菌的生长受到抑制。本文采用嗜酸氧化亚铁硫杆菌(Acidithiobacillus ferrooxidans,At.f)在不同条件下进行含砷难处理金精矿生物预氧化实验,研究生物预氧化过程中砷的价态变化及其对细菌生长情况的影响。实验结果表明:在生物预氧化过程中,微生物氧化作用产生的高氧化还原电位(大于480 mV)可以使矿物溶解释放出的三价砷较快地氧化为五价砷,使其毒性减弱。在实验中发现,较低的初始矿浆浓度和较高的细菌接种量有利于产生较高氧化还原电位,使生物预氧化操作顺利启动。  相似文献   

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