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1.
Summary Total and specific activities of extra-cellular laccases from Lentinus edodes were enhanced by adding corn straw and chestnut juice to the liquid growth medium. The aqueous extracts were chemically characterized and revealed the presence of several phenolic and non-phenolic compounds. Extensive extraction of these components from the tested extracts completely annulled their stimulating properties on laccase production, suggesting that these compounds can act at micromole levels.  相似文献   
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The objective of this study was to determine whether cells in G(0) phase are functionally distinct from those in G(1) with regard to their ability to respond to the inducers of DNA synthesis and to retard the cell cycle traverse of the G(2) component after fusion. Synchronized populations of HeLa cells in G(1) and human diploid fibroblasts in G(1) and G(0) phases were separately fused using UV-inactivated Sendai virus with HeLa cells prelabeled with [(3)H]ThdR and synchronized in S or G(2) phases. The kinetics of initiation of DNA synthesis in the nuclei of G(0) and G(1) cells residing in G(0)/S and G(1)/S dikaryons, respectively, were studied as a function of time after fusion. In the G(0)/G(2) and G(1)/G(2) fusions, the rate of entry into mitosis of the heterophasic binucleate cells was monitored in the presence of Colcemid. The effects of protein synthesis inhibition in the G(1) cells, and the UV irradiation of G(0) cells before fusion, on the rate of entry of the G(2) component into mitosis were also studied. The results of this study indicate that DNA synthesis can be induced in G(0)nuclei after fusion between G(0)- and S-phase cells, but G(0) nuclei are much slower than G(1) nuclei in responding to the inducers of DNA synthesis because the chromatin of G(0) cells is more condensed than it is in G(1) cells. A more interesting observation resulting from this study is that G(0) cells is more condensed than it is in G(1) cells. A more interesting observation resulting from this study is that G(0) cells differ from G(1) cells with regard to their effects on the cell cycle progression of the G(2) nucleus into mitosis. This difference between G(0) and G(1) cells appears to depend on certain factors, probably nonhistone proteins, present in G(1) cells but absent in G(0) cells. These factors can be induced in G(0) cells by UV irradiation and inhibited in G(1) cells by cycloheximide treatment.  相似文献   
4.

Introduction

Exercise training has emerged as a promising therapeutic strategy to counteract physical dysfunction in adult systemic lupus erythematosus. However, no longitudinal studies have evaluated the effects of an exercise training program in childhood-onset systemic lupus erythematosus (C-SLE) patients. The objective was to evaluate the safety and the efficacy of a supervised aerobic training program in improving the cardiorespiratory capacity in C-SLE patients.

Methods

Nineteen physically inactive C-SLE patients were randomly assigned into two groups: trained (TR, n = 10, supervised moderate-intensity aerobic exercise program) and non-trained (NT, n = 9). Gender-, body mass index (BMI)- and age-matched healthy children were recruited as controls (C, n = 10) for baseline (PRE) measurements only. C-SLE patients were assessed at PRE and after 12 weeks of training (POST). Main measurements included exercise tolerance and cardiorespiratory measurements in response to a maximal exercise (that is, peak VO2, chronotropic reserve (CR), and the heart rate recovery (ΔHRR) (that is, the difference between HR at peak exercise and at both the first (ΔHRR1) and second (ΔHRR2) minutes of recovery after exercise).

Results

The C-SLE NT patients did not present changes in any of the cardiorespiratory parameters at POST (P > 0.05). In contrast, the exercise training program was effective in promoting significant increases in time-to-exhaustion (P = 0.01; ES = 1.07), peak speed (P = 0.01; ES = 1.08), peak VO2 (P = 0.04; ES = 0.86), CR (P = 0.06; ES = 0.83), and in ΔHRR1 and ΔHRR2 (P = 0.003; ES = 1.29 and P = 0.0008; ES = 1.36, respectively) in the C-SLE TR when compared with the NT group. Moreover, cardiorespiratory parameters were comparable between C-SLE TR patients and C subjects after the exercise training intervention, as evidenced by the ANOVA analysis (P > 0.05, TR vs. C). SLEDAI-2K scores remained stable throughout the study.

Conclusion

A 3-month aerobic exercise training was safe and capable of ameliorating the cardiorespiratory capacity and the autonomic function in C-SLE patients.

Trial registration

NCT01515163.  相似文献   
5.
The possible use of olive-mill wastewater (OMW) as a growth medium for the production of extracellular laccase and manganese peroxidase (MnP) from the white-rot fungus Panus tigrinus (P. tigrinus) CBS 577.79 was studied using a properly formulated OMW-based medium (2-fold diluted OMW supplemented with 0.5% sucrose and 0.1% yeast extract) either in a stirred-tank or an air-lift reactor. Solid-state fermentation (SSF) was also performed in a rotary drum reactor using maize stalks moistened with the OMW-based medium. Highest levels of laccase and manganese peroxidase activity were obtained in the stirred-tank reactor (4600+/-98 U l(-1) on day 13) and in the air-lift reactor (410+/-22 on day 7), respectively. Based on total enzyme activities, SSF appears to be more suitable than LSF but the latter exhibits better volumetric productivities.  相似文献   
6.
Three phenolic model compounds representing bonding patterns of residual kraft lignin were incubated with manganese peroxidase from Lentinula edodes. Extensive degradation of all the phenolic models, mainly occurring via side-chain benzylic oxidation, was observed. Among the tested model compounds the diphenylmethane alpha-5 phenolic model was found to be the most reactive, yielding several products showing oxidation and fragmentation at the bridging position. The non-phenolic 5-5' biphenyl and 5-5' diphenylmethane models were found unreactive.  相似文献   
7.
Immobilization of Lentinula edodes laccase on Eupergit C increased pH, thermal and proteolytic stability with slight modifications in laccase oxidation efficiency. Immobilized laccase proved to be efficiently stable in removing olive mill wastewater phenolics.  相似文献   
8.
The ability of two strains of Lactobacillus acidophilus, CRL 640 and CRL 800, to survive and retain their biological activities under frozen storage was determined. Freezing and thawing, as well as frozen storage, damaged the cell membrane, rendering the microorganisms sensitive to sodium chloride and bile salts. Both lactic acid production and proteolytic activity were depressed after 21 days at -20 degreesC, whereas beta-galactosidase activity per cell unit was increased. Cell injury was partially overcome after repair in a salt-rich medium. Copyright 1998 Academic Press.  相似文献   
9.
To enhance diagnostic or therapeutic efficacy, novel nanomaterials must be engineered to function in biologically relevant environments, be visible by conventional fluorescent microscopy, and have multivalent loading capacity for easy detection or effective drug delivery. Here we report the fabrication of silica nanoparticles doped with quantum dots and superficially functionalized with amino and phosphonate groups. The amino groups were acylated with a water-soluble biotin-labeling reagent. The biotinylated nanoparticles were subsequently decorated with neutravidin by exploiting the strong affinity between neutravidin and biotin. The resultant neutravidin-decorated fluorescent silica nanoparticles stably dispersed under physiological conditions, were visible by conventional optical and confocal fluorescent microscopy, and could be further functionalized with macromolecules, nucleic acids, and polymers. We also coated the surface of the nanoparticles with biotinylated mouse anti-human CD3 (alphaCD3). The resultant fluorescent nanoassembly was taken up by Jurkat T cells through receptor-mediated endocytosis and was partially released to lysosomes. Thus, quantum dot-doped silica nanoparticles decorated with neutravidin represent a potentially excellent scaffold for constructing specific intracellular nanoprobes and transporters.  相似文献   
10.
Giardia duodenalis is a well recognised enteropathogen, while Dientamoeba fragilis is rarely detected and consequently it is not recognised as an important human pathogen. In 2002-2003, a survey has been carried out on enteroparasites in faecal samples of outpatients attending a day care centre in the town of Perugia (Central Italy). To improve the detection level, at least three samples from each patient were collected at different days and within two hours from defecation. The coproparasitological examination has been carried out by direct microscopic examination, faecal concentration, and Giemsa and modified Ziehl-Nielsen stainings of faecal smears. The genotypes of Giardia duodenalis isolates were determined by PCR of the beta-giardin gene. Of 1,989 enrolled people (966 children, 1,023 adults), 165 persons (8.3%; 153 adults, 15.0%; 12 children, 1.2%), were positive for parasites, but only 1 12 adults (73.2% of those infected) and eight children (66.7% of those infected) harboured D. fragilis and G. duodenalis. Both the Assemblages A and B were detected in 18 G. duodenalis isolates examined at the beta-giardin gene. The higher prevalence of D. fragilis infections than that of G. duodenalis is probably related to the method used, a procedure, which is rarely followed in laboratories for the diagnosis of enteric parasites. These epidemiological data suggest that when faecal samples are examined after a period of time and without Giemsa staining, most D. fragilis infections goes undetected.  相似文献   
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