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151.
MG Marciani G Santone G Sancesario R Massa P Stanzione G Bernardi 《Canadian Metallurgical Quarterly》1993,8(2):115-120
Phenotypic and functional aspects of melanoma-hyaluronate interactions were investigated by studying the expression of CD44, cell migration, and transmembrane penetration of human melanoma cell lines on hyaluronate-coated substrates. Expression of CD44 was tested by flow cytometry on seven human melanoma cell lines. Strong reactivity with anti-CD44 monoclonal antibody was observed in four of seven of the cell lines. Migration studies of CD44(+) cell lines on hyaluronic acid- and chondroitin-6-sulfate-coated substrates, using time-lapse video-microscopy, showed a dramatic dose-dependent increase in migration rate on hyaluronate but not on chondroitin-6-sulfate. Moreover, CD44(-) cell lines showed no modification in migration rate on either substrate. Addition of soluble hyaluronate produced a dose-dependent inhibition of acceleration of CD44(+)cells on hyaluronate-coated substrates, whereas addition of chondroitin-6-sulfate had no effect. Migration inhibition experiments with soluble CD44 (CD44 receptor globulin) also showed specific blocking of the migration of CD44(+) cells on hyaluronate. Haptotactic invasion was increased in CD44(+) cell lines through hyaluronate-coated polycarbonate membranes, whereas no change was detected on chondroitin-6-sulfate-coated membranes. CD44(-) cell lines showed no response to either type of coating. In the melanoma cell lines tested, the expression of CD44 correlated with in vitro migration and invasiveness on hyaluronate substrates. Taken together, our data are consistent with the suggestion that CD44 may play a role in stimulating in vivo aggressiveness of tumors through hyaluronate-rich stroma. 相似文献
152.
U Carcassi GS Del Giacco A Pintus G Perpignano F Locci M Loy MG Batzella G Piludu L Cengiarotti G Ibba AL Leone 《Canadian Metallurgical Quarterly》1977,54(3):285-287
Wind enhances the carcinogenic effect of chronic Iltraviolet radiation (UVL). This was demonstrated in hairless mice that were irradiated for 42 weeks with mercury are lamps. One group of animals was exposed to continuous wind flow of 2.7 m/s except for the daily I-2 min time interval when they were removed from the wind tunnel and irradiated. Another group of animals received identical irradiation but were protected from wind. The first tumour appeared in the UVL and wind group after 105 days of irradiation, and at 164 days of irradiation all surviving mice in the group had developed tumours. The group of mice receiving identical irradiation but protected from wind had their first tumour appear at 154 days of irradiation, and by 164 days of irradiation only 40% of the mice had developed tumours. 相似文献
153.
Kainic acid-induced status epilepticus results in delayed degeneration of CA3 hippocampal neurons in the mature but not immature rat hippocampus. In adult rats, the putative opioid precursor, preproenkephalin (PPE) mRNA increases in the dentate gyrus (DG), a region resistant to damage, following continuous limbic seizures. To explore why the immature brain is resistant to seizure-induced damage, the regional distribution of PPE mRNA expression and 45Ca2+ accumulation were compared in postnatal day 14 (P14) pup, and adult hippocampus at 5-6 h after kainate-induced status epilepticus. Inverted patterns of PPE expression and Ca2+ uptake were observed at the two ages. In P14 pups, PPE mRNA expression increased in DG and escalated in CA3, regions where 45Ca2+ accumulations were absent. In adult rats, PPE mRNA expression increased only in DG; 45Ca2+ labeling was predominant in CA3a,c and absent in DG. Pronounced increases in enkephalin neuropeptide synthesis in immature CA3 neurons may reduce glutamate release presynaptically and also prevent voltage-gated Ca2+ uptake into these neurons despite recurrent seizure activity. Opioid-mediated inhibition may provide an explanation for the resistance of the immature CA3 region to seizure-induced damage. 相似文献
154.
SD Gettings RA Lordo KL Hintze DM Bagley PL Casterton M Chudkowski RD Curren JL Demetrulias LC Dipasquale LK Earl PI Feder CL Galli SM Glaza VC Gordon J Janus PJ Kurtz KD Marenus J Moral WJ Pape KJ Renskers LA Rheins MT Roddy MG Rozen JP Tedeschi J Zyracki 《Canadian Metallurgical Quarterly》1996,34(1):79-117
The CTFA Evaluation of Alternatives Program is an evaluation of the relationship between data from the Draize primary eye irritation test and comparable data from a selection of promising in vitro eye irritation tests. In Phase III, data from the Draize test and 41 in vitro endpoints on 25 representative surfactant-based personal care formulations were compared. As in Phase I and Phase II, regression modelling of the relationship between maximum average Draize score (MAS) and in vitro endpoint was the primary approach adopted for evaluating in vitro assay performance. The degree of confidence in prediction of MAS for a given in vitro endpoint is quantified in terms of the relative widths of prediction intervals constructed about the fitted regression curve. Prediction intervals reflect not only the error attributed to the model but also the material-specific components of variation in both the Draize and the in vitro assays. Among the in vitro assays selected for regression modeling in Phase III, the relationship between MAS and in vitro score was relatively well defined. The prediction bounds on MAS were most narrow for materials at the lower or upper end of the effective irritation range (MAS = 0-45), where variability in MAS was smallest. This, the confidence with which the MAS of surfactant-based formulations is predicted is greatest when MAS approaches zero or when MAS approaches 45 (no comment is made on prediction of MAS > 45 since extrapolation beyond the range of observed data is not possible). No single in vitro endpoint was found to exhibit relative superiority with regard to prediction of MAS. Variability associated with Draize test outcome (e.g. in MAS values) must be considered in any future comparisons of in vivo and in vitro test results if the purpose is to predict in vivo response using in vitro data. 相似文献
155.
Effect of PEF and heat pasteurization on the physical-chemical characteristics of blended orange and carrot juice 总被引:1,自引:0,他引:1
The effect of different Pulsed Electric Fields (PEF) intensities (25 kV/cm and 280 μs, P1; and 25 kV/cm and 330 μs, P2) and conventional HTST treatment (98 °C, 21 s, T) on quality characteristics (pH, °Brix, total acidity, turbidity, hydroxymethylfurfural (HMF), color, microbial flora, pectinmethylesterase (PME) activity, and sensory analysis) of blended orange and carrot juice were investigated. HMF, L* (luminosity) and C* (saturation or chrome) color parameters did not vary with any of the treatments. Total acidity and turbidity were slightly higher after HTST treatment. Sensory characteristics of the PEF-treated juice were more similar to the untreated juice than the HTST-pasteurized juice. Nevertheless, heat pasteurization (98 °C, 21 s) was more efficient in inactivating microbial flora and PME and preventing the growth of microbial flora and reactivation of PME at 2 and 12 °C for 10 weeks. However, the shelf-life of the PEF-treated juice was established as 4 weeks at 2 °C. This appears to be a reasonable shelf-life for this type of foodstuff. 相似文献
156.
SH Thomas JE Horner K Chew J Connolly B Dorani L Bevan S Bhattacharyya MG Bramble KH Han A Rodgers B Sen B Tesfayohannes H Wynne DN Bateman 《Canadian Metallurgical Quarterly》1997,16(9):495-500
1. Paracetamol is increasingly involved in self-poisoning in the United Kingdom and remains a common cause of fatal poisoning. 2. To document the epidemiology and early management of paracetamol poisoning data were collected on consecutive patients with suspected paracetamol poisoning presenting to 6 hospitals in the North East of England over 12 weeks in 1994. 3. There were 400 presentations (attendance rate 1.14/10(3) population/yr) involving 343 persons (45% male). Paracetamol concentrations at 4 h correlated weakly with reported paracetamol dose (R = 0.49, P < 0.0001) and were similar comparing those treated and not treated by gastric decontamination. 4. In 38 (9%) cases paracetamol concentrations were above the appropriate nomogram treatment line, including 3% and 20% of patients who reported ingesting less than and more than 12 g respectively. In 21 patients acetylcysteine treatment was deferred until admission to the ward, the mean delay involved was 2.8 h. 5. One patient died, from arrhythmias caused by co-ingested dothiepin. 6. Paracetamol poisoning is common. Most cases do not have potentially toxic plasma paracetamol concentrations, but those who do often present late and antidotal treatment may be delayed inappropriately. 相似文献
157.
158.
Phenolic acids account for almost one third of the dietary phenols and are associated with organoleptic, nutritional and antioxidant properties of foods. This study was undertaken to assess the ability of Lactobacillus plantarum CECT 748T to metabolize 19 food phenolic acids. Among the hydroxycinnamic acids studied, only p-coumaric, caffeic, ferulic and m-coumaric acids were metabolized by L. plantarum. Cultures of L. plantarum produced ethyl and vinyl derivatives from p-coumaric and caffeic acids, 4-vinyl guaiacol from ferulic acid, and 3-(3-hydroxyphenyl) propionic acid from m-coumaric acid. Among the hydroxybenzoic acids analysed, gallic acid and protocatechuic acid were decarboxylated to pyrogallol and catechol, respectively. Inducible enzymes seem to be involved, at least in m-coumaric and ferulic acid metabolism, since cell-free extracts from cultures grown in the absence of these phenolic acids were unable to metabolize them. Further work is needed for the identification of the enzymes involved, since the knowledge of the metabolism of phenolic compounds is an important issue for the food industry. 相似文献
159.
NV Tat'ianko LL Gromashevskaia AD Vovk MG Kasatkina OV Liashok VI Matiash SP Iasinovy? IaN Kovgan 《Canadian Metallurgical Quarterly》1996,(5-6):119-122
In this paper, characterization is given of clinical and biochemical features of VH B course against the background of narcomania. Recordable in such patient populations are high percentage of delta hepatitis (14.2%), unusual severity of the intoxication syndrome, protracted course with exacerbations (12.2%) and recurrences (8%), outcome being a chronic hepatitis (14.2%), slower normalization of biochemical indicators, persistently low ratio of AIAT activity in diluted and whole blood sera. The persistence of viral markers in drug addicts discharged from the hospital (68%) is fraught with danger of spreading viral hepatitis of prophylactic measures are not strictly observed. 相似文献
160.
Tumor necrosis factor-alpha (TNF-alpha) is thought to be an important mediator in the pathogenesis of neonatal septicemia. To assess the role of TNF-alpha in neonatal sepsis, serum levels of TNF-alpha were measured in a group of neonates with septicemia and compared with the levels of gestational-postnatal, age-matched healthy controls. The relationships between severity of infection, the nature of causative microorganisms, and TNF-alpha levels were also investigated in this prospective study. A total of 49 infants (25 full-term, 24 preterm) with proven sepsis and 40 healthy infants (20 full-term, 20 preterm) were included. Serum TNF-alpha levels were measured using the TNF-alpha immunoradiometric assay. The median level of TNF-alpha was found to be significantly higher in infants suffering from sepsis (154 pg/mL) particularly in those with septic shock (242.5 pg/mL) as compared to healthy controls (61.5 pg/mL) (p < 0.001). No correlation was found between TNF-alpha and postnatal ages, gestational ages or birth weights of the infants. TNF-alpha levels were not different in surviving and terminal neonates. Although serum, TNF-alpha levels were found to be slightly higher in gram-negative septicemia, the difference was not significant. These findings suggest that TNF-alpha plays an important role in the pathophysiology of neonatal septicemia, but its importance as a prognostic factor is not yet clear. 相似文献