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71.
C Fabris D Basso L Benini T Meggiato G Del Favero G Cavallini M P Panozzo P Fogar C Angonese I Vantini 《Enzyme》1989,42(2):80-86
Serum and urine elastase 1, its renal output and clearance and urinary gamma-glutamyltransferase and ribonuclease excretions were measured in 16 patients with pancreatic cancer, 23 with chronic pancreatitis and in 22 healthy controls in order to evaluate elastase 1 plasma-urine transfer in chronic pancreatic disease and to investigate any factors that might influence the clearance of this enzyme. In an additional group of 17 patients with different pancreatic diseases the serum molecular size distribution of elastase 1 after chromatography was ascertained. An increased urinary elastase 1 output was found in 4/16 patients with pancreatic cancer and in 6/23 with chronic pancreatitis. No correlation was found between circulating elastase 1 and its urinary output; a negative correlation was detected between the serum levels of this enzyme and its clearance. The excretion of ribonuclease and gamma-glutamyltransferase was correlated with elastase 1 output and clearance. While the majority of elastase 1 in serum was accounted for by high molecular forms, probably the expression of complexes with serum inhibitors, free circulating enzyme was present in all patients with high serum elastase 1. Our findings suggest that elastase 1 urinary excretion increases in some patients with chronic pancreatic disease regardless of the neoplastic or inflammatory nature of the illness. Although the availability of different amounts of ultrafiltrable enzyme may play a role in influencing elastase 1 plasma-urine transfer, renal tubular damage appears to be the most important factor influencing the increase in the urinary output of elastase 1. 相似文献
72.
I Mattsby-Baltzer M Sandin B Ahlstrm S Allenmark M Edebo E Falsen K Pedersen N Rodin R A Thompson L Edebo 《Applied microbiology》1989,55(10):2681-2689
The dynamics of microbial growth in metal-working fluids (MWF) and the effect of the addition of biocides were studied in large fluid systems, in this case, one central tank which holds 150 m3. In this system, populations of Pseudomonas pseudoalcaligenes (greater than 10(8) CFU/ml) were sustained for a year, although large quantities of biocides were added. Quantitation of 3-OH lauric acid, a marker for many Pseudomonas spp., by gas chromatography indicated that the bacterial biomass exceeded the viable counts by approximately 15 times. Fungi were grown on several occasions, the dominating genera being Fusarium and Candida. Soon after the old MWF was removed and the tank was provided with fresh MWF, which consisted of an emulsion of mineral oil in water, there was a massive growth of P. pseudoalcaligenes that reached levels of greater than 10(8) bacteria per ml. Initially, only low concentrations of other species were found for some weeks. After this period, different enterobacteria and other gram-negative rods often appeared at high concentrations (10(7) and 10(8) bacteria per ml, respectively). Bacteria identified as P. pseudoalcaligenes showed great variation with respect to colony morphology and a certain heterogeneity with respect to biochemical characteristics. Certain bacterial species grew as microcolonies on metal strips immersed in the circulating MWF, but P. pseudoalcaligenes was not recovered from this habitat. The total bacterial count in the air surrounding the machines in the metal-working shop showed an inverse relation to increasing distance from the machine. The concentration of bacteria in the air varied because of the number of machines in use, temperature, and humidity.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
73.
Survey of the Anaerobic Biodegradation Potential of Organic Chemicals in Digesting Sludge 总被引:4,自引:1,他引:3 下载免费PDF全文
The degradation potential of 77 organic chemicals under methanogenic conditions was examined with an anaerobic digesting sludge from the United Kingdom. Degradation was assessed in terms of net total gas (CH4 plus CO2) produced, expressed as a percentage of the theoretical production (ThGP). The compounds tested were selected from various chemical groups and included substituted phenols and benzoates, pesticides, phthalic acid esters, homocyclic and heterocyclic ring compounds, glycols, and monosubstituted benzenes. The results obtained were in good agreement with published surveys of biodegradability in U.S. digesting sludges and other methanogenic environments. In general, the presence of chloro or nitro groups inhibited anaerobic gas production, while carboxyl and hydroxyl groups facilitated biodegradation. The relationship between substituent position and susceptibility to methanogenic degradation was compound dependent. The following chemicals were completely degraded (≥80% ThGP) at a concentration of 50 mg of carbon per liter: phenol, 2-aminophenol, 4-cresol, catechol, sodium benzoate, 4-aminobenzoic acid, 3-chlorobenzoic acid, phthalic acid, ethylene glycol, diethylene glycol, triethylene glycol, sodium stearate, and quinoline. 3-Cresol, 4-chlorobenzoic acid, dimethyl phthalate, and pyridine were partially degraded. Although the remaining chemicals tested were either persistent or toxic, their behavior may differ at more environmentally realistic chemical-to-biomass ratios. Our findings suggest that biodegradability assessments made with sludge from one source can be extrapolated to sludge from another source with a reasonable degree of confidence and should help in predicting the fate of an organic chemical during the anaerobic digestion of sewage sludge. 相似文献
74.
A Del Corso D Barsacchi M Camici D Garland U Mura 《Archives of biochemistry and biophysics》1989,270(2):604-610
Two structurally different forms of bovine lens aldose reductase have been identified. Freshly prepared lens extracts contain an unactivated "b form" (ARb) which is sensitive to inhibition by Sorbinil. Upon incubation of the extracts with oxygen radical generating systems, ARb is converted to a more active "a form" (ARa), which is not inhibited by Sorbinil. ARa and ARb were purified to electrophoretic homogeneity. 相似文献
75.
Evidence for M?ssbauer spectroscopy for different forms of iron core in Pseudomonas aeruginosa bacterial ferritin. 下载免费PDF全文
N M Reid D P Dickson C Greenwood A Thompson F H Kadir G R Moore 《The Biochemical journal》1990,272(1):263-264
Mössbauer spectroscopic studies of whole cells of Pseudomonas aeruginosa, grown under different conditions, indicate that the predominant form of iron in the cells varies significantly. These differences are interpreted in terms of differences in the nature of the iron cores of the bacterial ferritin, which result from different growth conditions. 相似文献
76.
The temporal relationship between phospholipase activation, diradylglycerol formation and superoxide production in the human neutrophil. 总被引:2,自引:0,他引:2 下载免费PDF全文
N T Thompson J E Tateson R W Randall G D Spacey R W Bonser L G Garland 《The Biochemical journal》1990,271(1):209-213
Fluctuations in the amounts of choline, inositol 1,4,5-trisphosphate (IP3) and diradylglycerol have been used to monitor phospholipase activation in the human neutrophil. Stimulation of human neutrophils by formylmethionyl-leucylphenylalanine (fMet-Leu-Phe) resulted in a rapid activation of both phosphatidylinositol 4,5-bisphosphate breakdown by phospholipase C and phosphatidylcholine breakdown by phospholipase D. Diradylglycerol accumulation occurred more slowly than that of either choline or IP3 and was inhibited by 30 mM-butanol, suggesting that the bulk was derived from the phospholipase D pathway via phosphatidate phosphohydrolase. Consistent with this is the observation that choline and diradylglycerol are produced in similar amounts. 1,2-Diacylglycerol (DAG) and 1-O-alkyl-2-acyl-sn-glycerol species accumulated with different time courses, indicating that one or more steps in the phospholipase D pathway was selective for the diacyl species. Superoxide production by fMet-Leu-Phe-stimulated neutrophils paralleled DAG accumulation over the first 5 min, but thereafter this production stopped, despite the fact that DAG remained elevated. We conclude that DAG derived from the phospholipase D pathway is only one of the second messengers important in controlling this functional response. 相似文献
77.
A second nonrandom translocation, der(16)t(1;16)(q21;q13), in Ewing sarcoma and peripheral neuroectodermal tumor 总被引:1,自引:0,他引:1
E C Douglass S T Rowe M Valentine D Parham W H Meyer E I Thompson 《Cytogenetics and cell genetics》1990,53(2-3):87-90
The majority of Ewing sarcomas and peripheral neuroectodermal tumors (PNET) that have been karyotyped contain a specific translocation, t(11;22)(q23;q11). We report here a second nonrandom translocation, der(16)t(1;16)(q21;q13), in 2 of 20 cases of Ewing sarcoma (seven previously unreported) and 2 of 7 cases of PNET (all previously unreported). All cases with this translocation also contained the t(11;22). Comparison of C-banding patterns in tumor and peripheral lymphocyte karyotypes in one case indicated that the likely breakpoints were 1q21 and 16q13. The presence of this translocation in cell lines will enable further investigation of the molecular events important in the pathogenesis of Ewing sarcoma and PNET. 相似文献
78.
Construction of a human chromosome 3 specific NotI linking library using a novel cloning procedure. 总被引:1,自引:0,他引:1 下载免费PDF全文
E R Zabarovsky F Boldog T Thompson D Scanlon G Winberg Z Marcsek R Erlandsson E J Stanbridge G Klein J Sümegi 《Nucleic acids research》1990,18(21):6319-6324
Two new diphasmid vectors (lambda SK17 and SK22) and a novel procedure to construct linking libraries are described. A partial filling-in reaction provides counter-selection against false linking clones in the library, and obviates the need for supF selection. The diphasmid vectors, in combination with the novel selection procedure, have been used to construct a chromosome 3 specific NotI linking library from a human chromosome 3/mouse microcell hybrid cell line. The application of the new vectors and the strong biochemical and biological selections resulted in a library of 60,000 NotI linking clones. As practically all of them are real NotI linking clones (no false recombinants) the library represents approximately 3,000 human recombinants (equal to 10-15 genomic equivalents of chromosome 3). Previously published methods for construction of linking libraries are compared with the procedure described in the present paper. The advantages of the new vectors and the novel protocol are discussed. 相似文献
79.
We have analyzed changes in the structure of chloroplast chromosomes in response to light in growing Chlamydomonas cells using a crosslinking assay based on the intercalation of HMT (4'-hydroxymethyl-4,5',8-trimethylpsoralen) into DNA. Our results show that the structure of chloroplast chromosomes in at least three widely separated regions is different in light-grown vs. dark-grown cells. Structural changes in chloroplast chromosomes occur within 3 hrs after exposure to light or darkness, respectively. The response to light is not inhibited by atrazine and can be elicited by dim blue light incapable of evolving O2, indicating that it does not require photosynthesis. Inhibition of cytoplasmic protein synthesis with cycloheximide prevents this response to light, indicating that it depends, at least in part, on proteins imported from the cytoplasm. 相似文献
80.
Efficient site directed in vitro mutagenesis using ampicillin selection. 总被引:11,自引:1,他引:10 下载免费PDF全文
A novel plasmid vector pSELECT-1 is described which can be used for highly efficient site-directed in vitro mutagenesis. The mutagenesis method is based on the use of single-stranded DNA and two primers, one mutagenic primer and a second correction primer which corrects a defect in the ampicillin resistance gene on the vector and reverts the vector to ampicillin resistance. Using T4 DNA polymerase and T4 DNA ligase the two primers are physically linked on the template. The non-mutant DNA strand is selected against by growth in the presence of ampicillin. In tests of the vector, highly efficient (60-90%) mutagenesis was obtained. 相似文献