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991.
Selznick SH Thatcher ML Brown KS Haussler CA 《In vitro cellular & developmental biology. Animal》2001,37(1):55-61
Prototype computer software for a Cell Culture Laboratory Management System (CCLMS) has been developed to relieve cell culture specialists of the burden of manual recordkeeping. Conventional data archives in cell culture laboratories are prone to error and expensive to maintain. The reliance upon cell culture to provide models for biochemical and molecular biological research serves to magnify errors at great expense. The CCLMS prototype encapsulates a modular software application that manages the many aspects of cell culture laboratory recordkeeping. A transaction-based database stores detailed information on subcultures, freezes and thaws, prints waterproof labels for culture vessels, and provides for immediate historical trace-back of any cultured cell line. Linked database files store information specific to an individual culture flask while removing redundancy between similar groups of flasks. A frozen cell log maintains locations of all vials within any type of cryogenic storage unit, locates spaces for newly frozen cell lines, and generates alphabetical or numerical reports. Finally, modules for maintaining cell counts, user records, and culture vessel specifications to support a comprehensive automation process are incorporated within this software. The developed CCLMS prototype has been demonstrated to be an adaptable, reliable tool for improving training, efficiency, and historical rigor for two independent cell culture facilities. 相似文献
992.
A study was made of cambial activity, the localization of storage starch around the cambium, and the localization and occurrence
of microtubules in cambial cells from dormancy to reactivation in locally heated (22–26 °C) stems of the evergreen conifer
Abies sachalinensis. Heating induced localized reactivation of the cambium in the heated portions of the stem. Erect ray cambial cells resumed
cell division 1 d prior to the reactivation of fusiform cambial cells and procumbent ray cambial cells. The re-initiation
of the division of fusiform cambial cells occurred first on the phloem side. During the heat treatment, the amount of storage
starch decreased in procumbent ray cambial cells and in the phloem parenchyma adjacent to the cambium but increased in fusiform
cambial cells. Preprophase bands of microtubules, spindle microtubules and phragmoplast microtubules were observed both in
erect ray cambial cells and in procumbent ray cambial cells. By contrast, no evidence of the presence of such preprophase
bands of microtubules was detected in fusiform cambial cells. The results suggest that the localized heating of stems of evergreen
conifers might provide a useful experimental model system for studies of the dynamics of cambial reactivation in intact trees.
Received: 25 May 2000 / Accepted: 12 July 2000 相似文献
993.
Improved Human Sperm Recovery Using Superoxide Dismutase and Catalase Supplementation in Semen Cryopreservation Procedure 总被引:2,自引:0,他引:2
The aim of this work was to evaluate the effects of ROS scavenger supplementation in human semen samples undergoing cryopreservation procedures.After screening out andrological pathologies, we selected 25 male partners of infertile couples with the following semen profile: volume >/= 2.0 ml, normal viscosity, sperm count >/=20 x 10(6)/ml, straight progressive motility (classes 1 and 2) >/= 40% (Mazzilli, Rossi, Delfino and Nofroni (1999) Andrologia 31: 187-194), atypical forms = 70%, WBCs < 1.0 times 10(6)/ml.After liquefaction, standard semen analysis and the Hypoosmotic Viability Test (HVT) were carried out; the samples were then divided into 4 aliquots. The first was untreated as a control; 200 U/ml of superoxide dismutase (SOD) was added to the second, 200 U/ml of catalase to the third and both SOD (100 U/ml) and catalase (100 U/ml) were added to the fourth aliquot. Each aliquot was mixed (v/v) with TEST yolk buffer freezing medium (Irvine Scientific) and then frozen at -196 degrees C. The percent recovery of progressive motile and swollen spermatozoa was evaluated after thawing.No significant variation in the recovery of progressive motility was seen in the aliquots with added SOD or catalase alone, compared to the control group. On the other hand, a significant improvement in sperm parameter recovery was seen in the aliquot with both SOD and catalase supplementation; perhaps because of their combined and simultaneous action on superoxide anion and hydrogen peroxide. These results suggest that, in some selected cases, SOD and catalase supplementation can contribute greatly to the prevention of sperm membrane lipid peroxidation by ROS and thus allow good sperm parameter recovery after freezing-thawing procedures. 相似文献
994.
Masayuki Saigusa 《Ecological Research》2001,16(1):1-28
Many small invertebrates inhabit the shallow subtidal zone and some of them emerge at times into the water column. The daily timing of their emergence is affected by the day/night and tidal cycles, and shows various patterns of synchrony with these cyclical factors, depending on the species. To detect possible regional differences in their emergence patterns, sampling was carried out at four locations in Japan: a boreal sea (Akkeshi), a temperate sea (Sugashima), an inland sea (Ushimado) and a subtropical sea (Iriomote-jima). The emergence patterns of major taxa were examined by visual inspection and by two statistical methods (periodogram and autocorrelogram). The composition of the taxa collected by the pump system, mostly crustaceans, was similar in each location. The number of taxa that emerged revealed a day/night rhythm in every location. This characteristic was clearest at Iriomote-jima and least clear at Sugashima. The daily fluctuation in the number of individuals in each taxon varied widely, from very clearly nocturnal to weakly diurnal patterns. In Iriomote-jima, the major taxa all showed well-demarcated nocturnal patterns, so these patterns were classified as either level N2 or N3 with regard to the degree of synchrony with the day/night cycle. With regard to the synchrony with the tide, the majority of patterns in all locations showed a double-tidal interval. Many patterns were slightly modified by the tidal cycle. These patterns were classified as level T1 or T2 with regard to the degree of synchrony with the tidal cycle. The synchrony with the tide was comparatively strong at Ushimado. The synchrony with day/night and tidal cycles varied even within the same species or closely related species. In benthic invertebrates, hiding or resting in the bottom substrates and swimming in the water column would occur alternatively. In planktonic animals, aggregation near the bottom and dispersal in the water column would occur alternatively. The daily timing of such activities may be synchronized with the day/night and tidal cycles to various degrees among species or populations, resulting in a wide variety of emergence patterns in subtidal small invertebrates. This type of behavior is not daily (diel) vertical migration; it should rather be called daily emergence/dispersal. Strong winds, rough waves and unknown seasonal factors would also affect emergence patterns. Furthermore, the transparency of the seawater may also strongly affect these patterns. Nocturnal patterns may be an adaptation to avoid vulnerability to sighted predators. Variation of synchrony with the tide indicates that by definition, the tidal rhythm can only be distinguished from the day/night rhythm. Hence, the daily patterns that are weakly modified by the tides (levels T1 and T2) should be called the tidal rhythms. As the period of such rhythms cannot be determined exactly by using statistical methods, lengthy field investigations and visual inspection of each pattern is essential to assess the influence of tides. 相似文献
995.
Biotransformation kinetics of Pseudomonas putida for cometabolism of phenol and 4-chlorophenol in the presence of sodium glutamate 总被引:5,自引:0,他引:5
A kinetic model to describe the degradation of phenol and cometabolictransformation of 4-chlorophenol (4-cp) in the presence of sodium glutamate(SG) has been developed and validated experimentally. The integrated modelaccounts for cell growth, toxicity of 4-cp, cross-inhibitions among the threesubstrates, and the different roles of the specific growth substrate (phenol)and the conventional carbon source (SG) in the cometabolism of 4-cp. In thisternary substrate system, the overall phenol degradation and 4-cp transformation rates are greatly enhanced by the addition of SG since SG is able to attenuate the toxicity of 4-cp and therefore increase the cell growth rate. Model analysis indicates that the maximum specific degradation rate of phenol (0.819 mg (mg.h)-1) is lowered by SG by up to 46% whereas the specific transformation rate of 4-cp is notdirectly affected by the presence of SG. The competitive inhibition coefficient of 4-cp to phenol degradation (Ki,cp) and that of phenol to 4-cp transformation (Ki,ph) were determined to be 6.49 mg l-1 and 0.193 mg l-1, respectively, indicatingthat phenol imposes much larger competitive inhibition to 4-cp transformation than the converse. The model developed can simultaneously predict phenol degradation and 4-cp transformation, and is useful for dealing with cometabolism involving multiple substrates. 相似文献
996.
Inhibitory effect of curcumin on the invasion of rat ascites hepatoma cells in vitro and ex vivo 总被引:1,自引:0,他引:1
Curcumin, a yellow pigment in turmeric, is a food factor withantioxidative activity. The effect of curcumin on the proliferation and invasion of the rat ascites hepatoma AH109Acells was studied in vitro and ex vivo assay systems. Especially, a co-culture system of the hepatoma cellswith mesothelial cells derived from rat mesentery was employed to investigate the invasive motility. Curcumin suppressed thehepatoma slipping motility in a dose-dependent manner up to 5 M and thereafter maintained the effect up to 20 M, whereas this substance exerted little influence on the proliferation of the hepatoma cells at the same concentrations. Sera obtained from rats orally given curcumin also inhibited the AH109A cellular invasive movement when added to the culturemedium. Hepatoma cells previously cultured with hypoxanthineand xanthine oxidase showed a highly invasive activity. Curcumin and curcumin-loaded rat sera suppressed this reactive oxygen species-potentiated invasive capacity by simultaneously treating AH109A cells with hypoxanthine, xanthine oxidase and either of curcumin samples. These resultssuggest that the antioxidative property of curcumin may beinvolved in its anti-invasive action. 相似文献
997.
998.
Giusto NM Salvador GA Castagnet PI Pasquaré SJ Ilincheta de Boschero MG 《Neurochemical research》2002,27(11):1513-1523
In this review, changes in brain lipid composition and metabolism due to aging are outlined. The most striking changes in cerebral cortex and cerebellum lipid composition involve an increase in acidic phospholipid synthesis. The most important changes with respect to fatty acyl composition involve a decreased content in polyunsaturated fatty acids (20:4n-6, 22:4n-6, 22:6n-3) and an increased content in monounsaturated fatty acids (18:1n-9 and 20:1n-9), mainly in ethanolamine and serineglycerophospholipids. Changes in the activity of the enzymes modifying the phospholipid headgroup occur during aging. Serine incorporation into phosphatidylserine through base-exchange reactions and phosphatidylcholine synthesis through phosphatidylethanolamine methylation increases in the aged brain. Phosphatidate phosphohydrolase and phospholipase D activities are also altered in the aged brain thus producing changes in the lipid second messengers diacylglycerol and phosphatidic acid. 相似文献
999.
脑血红素加氧酶系统的作用研究 总被引:7,自引:0,他引:7
血红素加氧酶(HO)是降解血红素的微粒体酶系统,催化降解血红素生成一氧化碳(CO)、胆绿素和铁离子,同工酶HO-1和HO-2广泛分布于脑中,具有不同的调控机制,可能发挥着调节NO水平,抗氧化应激,参与神经元退行性变等重要作用。 相似文献
1000.
Parrish AR Sallam K Nyman DW Orozco J Cress AE Dalkin BL Nagle RB Gandolfi AJ 《Cell biology and toxicology》2002,18(3):205-219
Due to the complex morphology of the prostate, it was hypothesized that precision-cut tissue slices from human prostate would
provide a unique in vitro model. Precision-cut slices were generated from zones of human prostate and their viability was assessed under conditions
of different media for up to 120 h. Slices were also exposed to several concentrations of CdCl2, which was used as a model toxicant. Maintenance of both stromal and epithelial cells was noted; however, there was a gradual
loss of luminal epithelial cells when the medium was not supplemented with dihydrotestosterone (DHT). Minimal leakage of lactate
dehydrogenase occurred throughout the incubation. Prostate-specific antigen (PSA) was detected in the medium at all time points,
although the rates of secretion fell over time. There was a loss of PSA-positive cells when the medium was not supplemented
with DHT, consistent with a loss of luminal cells, whereas PSA-positive cells were maintained in the DHT-supplemented media.
A proliferation of basal cells was observed in the presence of media containing 10% fetal bovine serum. Exposure of slices
to CdCl2 demonstrated a dose-response effect ranging from proliferation to complete cellular necrosis. Given the retention of stromal-epithelial
interactions and the use of acquired human tissue, prostate slices represent a unique in vitro model for investigating human prostate pathobiology.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献