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941.
942.
G Sozzi S Tornielli E Tagliabue L Sard F Pezzella U Pastorino F Minoletti S Pilotti C Ratcliffe ML Veronese P Goldstraw K Huebner CM Croce MA Pierotti 《Canadian Metallurgical Quarterly》1997,57(23):5207-5212
Genomic alterations and abnormal expression of the FHIT gene at 3p14.2 have been observed in cell lines and primary tumors of the lung. To correlate FHIT locus DNA and RNA lesions with effects on Fhit protein expression, we have analyzed 11 lung cancer cell lines, 15 small cell lung carcinomas, and 38 pairs of non-small cell primary tumors and bronchial mucosa specimens by molecular genetic and immunocytochemical methods. Using specific antibodies against the Fhit protein, we observed concordance between RNA abnormalities and lack of Fhit protein expression in lung tumors and cell lines. In addition, absence of Fhit protein in some precancerous dysplastic lesions suggested that FHIT inactivation may occur at an early phase of lung carcinogenesis. 相似文献
943.
Sebastià Puig Marta Coma Mark CM van Loosdrecht Jesús Colprim Maria D Balaguer 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2007,82(10):898-904
BACKGROUND: When organic matter is limiting for biological nutrient removal (BNR) from wastewater, external organic carbon can be added to a wastewater treatment plant (WWTP). This increases the overall treatment cost, so the choice of substrate is critical. The effect of using ethanol as the carbon source for BNR is investigated. RESULTS: The results clearly showed that using ethanol as a carbon source is a promising strategy for removing nutrients from wastewater. Effluent concentrations of 3.0 mg total nitrogen (TN) L?1 (96% N removal efficiency) and 0.05 mg phosphate (P‐PO4) L?1 (99.9% P removal efficiency) were obtained. Furthermore, tests performed in order to identify the carbon source used by polyphosphate‐accumulating organisms (PAOs) showed that the phosphorus release/carbon uptake ratio using ethanol (0.41 mmol P mmol?1 C) was slightly lower than that with acetate (0.50 mmol P mmol?1 C) but close to that with propionate (0.42 mmol P mmol?1 C). CONCLUSION: Therefore, taking into account the results presented for ethanol‐acclimatised biomass and the fact that the cost of ethanol is lower than that of acetate or propionate, ethanol can be considered as an alternative carbon source if one is needed in a WWTP. Copyright © 2007 Society of Chemical Industry 相似文献
944.
945.
JT Brouwer F Nevens B Kleter A Elewaut M Adler R Brenard RA Chamuleau PP Michielsen J Pirotte ML Hautekeete J Weber N Bourgeois BE Hansen CM Bronkhorst FJ ten Kate RA Heijtink J Fevery SW Schalm 《Canadian Metallurgical Quarterly》1998,28(6):951-959
BACKGROUND/AIMS: In an attempt to improve the limited efficacy of treatment of chronic hepatitis C with interferon-alpha 3 MU tiw, we studied the effects of double-dose therapy followed by downward titration, and analyzed the pre- and pertreatment factors associated with response or non-response. METHODS: Three hundred and fifty-four consecutive patients in 19 centers were randomized to interferon-alpha 3 MU tiw for 6 months or 6 MU tiw for 8 weeks followed by down-titration (3,1 MU tiw) till alanine aminotransferase remained normal and plasma HCV RNA was repeatedly undetectable. The primary outcome measure was sustained alanine aminotransferase and HCV RNA response 6 months after treatment. RESULTS: Three hundred and thirty-six patients received treatment. The sustained response rate for patients receiving 3 MU tiw for 6 months was 14% (9-21%,) and for patients receiving double dose tiw for 8 weeks and thereafter titrated therapy 15% (10-21%) (p=0.8). Pretreatment factors associated with a sustained alanine aminotransferase plus HCV RNA response were the absence of cirrhosis, presence of genotype 2 or 3, a low viral load and, in addition, a low alanine aminotransferase/aspartate aminotransferase ratio; a model was developed to allow estimation of the chance of response for the individual patient. The most powerful predictor of sustained response, however, was plasma HCV RNA at week 4; a positive test virtually precluded a sustained response (1.7%, 0.4-5.0%). If week 4 HCV RNA was not detectable, the chance of a sustained response was 21% (12-34%) for genotype 1 versus 40% (28-54%) for the others (p=0.02). Six MU tiw led to a significantly higher week 4 HCV RNA response (47% not detectable) than 3 MU (37%) (p=0.02). During down-titration this difference in viral on-treatment response was lost. CONCLUSIONS: In the treatment of hepatitis C, an early HCV RNA response is a prerequisite for long-term efficacy. Doubling the initial interferon dose increases this early response, but subsequent downward titration negates this effect, especially in genotype 1. 相似文献
946.
M Rossi MS Kim DG Morgan CJ Small CM Edwards D Sunter S Abusnana AP Goldstone SH Russell SA Stanley DM Smith K Yagaloff MA Ghatei SR Bloom 《Canadian Metallurgical Quarterly》1998,139(10):4428-4431
Agouti-related protein (Agrp) is present in rat and human hypothalamus and is structurally related to agouti protein. Overexpression of either of these proteins results in obesity. However the effect of exogenous Agrp and its in vivo interaction with alpha-melanocyte stimulating hormone (alphaMSH), the likely endogenous melanocortin 3 and 4 receptor (MC3-R and MC4-R) agonist, have not been demonstrated. We report that 1 nmol of Agrp(83-132), a C-terminal fragment of Agrp, when administered intracerebroventricularly (ICV) into rats, increased food intake over a 24-h period (23.0+/-1.4 g saline vs 32.9+/-2.3 g Agrp, p<0.05). The hyperphagia was similar to that seen when 1 nmol of the synthetic MC3-R and MC4-R antagonist SHU9119 was given i.c.v. (19.6+/-1.8 g saline vs 32.5+/-1.7 g SHU9119, p<0.001). Both Agrp(83-132) and SHU9119 blocked the reduction in 1-h food intake of i.c.v. alphaMSH at the beginning of the dark phase. This effect occurred independently of whether the antagonists were administered simultaneously, or nine hours prior, to the alphaMSH. We have also shown Agrp(83-132) is an antagonist at the MC3-R and MC4-R, with similar inhibition of cAMP activation to that previously reported for the full length peptide. In conclusion, Agrp(83-132) administered i.c.v. increases feeding with long lasting effects and is able to inhibit the action of alphaMSH. This interaction may be mediated by the MC3-R and/or MC4-R. 相似文献
947.
L Stefanis CM Troy H Qi ML Shelanski LA Greene 《Canadian Metallurgical Quarterly》1998,18(22):9204-9215
We have previously shown that caspase-2 (Nedd-2) is required for apoptosis induced by withdrawal of trophic support from PC12 cells and sympathetic neurons. Here, we examine the relationship of caspase-2 processing and cell death to induction of caspase-3 (CPP32)-like activity in PC12 cells. Caspase-2 processing, at a site tentatively identified as D333, led to the formation of an N-terminal 37 kDa product. This processing correlated temporally with induction of caspase-3-like activity. Agents previously shown to inhibit caspase-3-like activation, such as bcl-2 and the Cdk inhibitor flavopiridol, also acted upstream of caspase-2 processing. The general caspase inhibitors BAF and zVAD-FMK inhibited N-terminal caspase-2 processing. In contrast, the more selective caspase inhibitor DEVD-FMK inhibited the induction of caspase-3-like activity but did not affect caspase-2 processing or significantly suppress death in PC12 cells or sympathetic neurons. This indicates that caspase-3-like activity is not required for either caspase-2 processing or apoptosis in this paradigm. An antisense oligonucleotide to caspase-2 inhibited cell death but did not affect caspase-3-like activity, indicating that caspase-2 is not upstream of this activity and that activation of caspase-3-like caspases is not sufficient for death. Thus, in our paradigm, caspase-2 processing and caspase-3-like activity are induced independently of each other. Moreover, although death requires caspase-2, caspase-3-like activity is neither necessary nor sufficient for death. 相似文献
948.
A 39-year-old woman suffered from swelling and tenderness of the right leg for 31 years. Imaging studies showed a large soft tissue lesion on the right side extending from the proximal portion of the thigh to the ankle. She underwent several operations due to the leg mass and associated equinovarus deformity of the right ankle. The pathologic findings were those of an ossified cavernous hemangioma. This appears to be one of the largest hemangiomas to be reported. It revealed the three types of calcification characteristic of hemangiomas. Equinovarus deformity of the ankle caused by contracture of the calf in this case was probably related to repeated bleeding. 相似文献
949.
G Karakousis N Ye Z Li SK Chiu G Reddy CM Radding 《Canadian Metallurgical Quarterly》1998,276(4):721-731
Phage lambda encodes two recombination proteins that are required for homologous recombination in a recA- host strain. Of these two recombination proteins, one is an exonuclease whose action on double-stranded DNA produces 3' single-stranded ends; the other, called beta protein, is a DNA binding protein that promotes the renaturation of complementary single strands. The enzymes of phage lambda provide a model for understanding a recombination pathway called "single-strand annealing". Further investigation of the binding of beta protein to DNA has revealed a new mechanism of renaturation. As reported before, beta protein binds directly to single-stranded DNA, but not to double-stranded DNA. However, in the experiments reported here, we observed that beta protein bound more strongly to a presumed intermediate in the renaturation reaction that beta itself catalyzed, and beta thereby protected all of a renatured duplex 83-mer oligonucleotide from nuclease digestion. 相似文献
950.
The kinetic properties of cartridge and disk solid-phase extraction devices are determined by forced-flow liquid chromatography. Typical cartridges provide about 5-15 theoretical plates per cm of bed height and particle-loaded membranes provide about 4-9 theoretical plates for a 0.5-mm-thick membrane. It is shown that cartridge devices fail to provide their maximum trapping performance because of inadequate packing density and that the required packing density could be easily achieved in practice with particles of a standard size. The retention properties of common sorbents for extraction from water and air are characterized with the solvation parameter model. For predominantly aqueous solutions a favorable cavity term results in increased retention while polar interactions tend to reduce retention. Retention on porous polymer sorbents is more complicated because of their capacity to absorb significant amounts of the sample processing solvent resulting in solvent-dependent changes in retention properties. For trapping organic volatiles from air cavity formation and dispersion interactions are important, and in the case of Tenax its capacity for induction interactions is also significant. 相似文献