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Kerrigan CL Collins ED Kneeland TS Voigtlaender D Moncur MM Matheney TH Grove MR Tosteson AN 《Plastic and reconstructive surgery》2000,106(2):280-288
The purpose of this article is to introduce the measurement of utilities, or patient preferences, to the plastic surgery community. Specifically, the study demonstrated the development and validation of a utility measure for estimating the health-related quality of life in women with breast hypertrophy. Two self-administered instruments were developed, a Wheel and a Table. All subjects completed the utility assessments for their "current health" and again for "breast-related symptoms." The reliability of the instruments was assessed in repeat (test-retest) interviews of 47 women within 10 to 18 days. Utilities obtained with the new instruments were also compared with the performance of other validated utility assessment instruments, including a visual analogue scale, a computer-based instrument (U-Titer), and a preference classification system (EuroQol). Of the 47 women in the test-retest reliability study, 21 had experienced breast hypertrophy (13 had not had reduction surgery and 8 had undergone reduction mammaplasty). Mean utility values for breast-related symptoms among women with breast hypertrophy (n = 13) were: Table, 0.85; Wheel, 0.90; and U-Titer, 0.66. Current health utility scores were significantly lower for women with breast hypertrophy (n = 13), as measured by all instruments except the Wheel. The Table had good reliability and distinguished women with breast hypertrophy from those without. Although the Table provided higher utility values for the same health state compared with the computer-based interview (U-Titer), it is much less costly to implement. The Table is recommended as a reasonable alternative for use in multicenter studies of women with breast hypertrophy. The reported utility value for breast hypertrophy of 0.86 is much lower than predicted. It is comparable with the reported burden of living with other health conditions, such as moderate angina (0.90) and a kidney transplant (0.84). 相似文献
55.
Nathalie Baghdassarian Régine Catallo Mohamed A. Mahly Patrick Ffrench Florence Chizat Paul A. Bryon Martine Ffrench 《Experimental cell research》1998,240(2):263
In order to analyze dexamethasone effects on peripheral blood lymphocyte proliferation, we defined various experimental conditions: dexamethasone introduced (i) at the time of phytohemagglutinin stimulation, (ii) 48 h after the beginning of phytohemagglutinin stimulation, and (iii) on unstimulated lymphocytes. In stimulated lymphocytes, we observed an early G1 accumulation (P< 0.005), a delayed increase in the duration of S-phase (P< 0.03), and a consequent increase in cell-cycle duration. The expression of several cyclins, cyclin-dependent kinases (CDKs), and CDK inhibitors (CKIs) was modified. Cyclin D3, CDK4, and CDK6 involved in G1-phase control were significantly decreased under dexamethasone treatment whatever the level of stimulation of lymphocytes (stimulated or unstimulated PBL). Cyclin E and CDK2, acting in G1/S-phase transition and S-phase regulation, decreased in stimulated lymphocytes before any modification of S-phase (P< 0.002). The expression of CKIs, mainly of p27Kip1, appeared to vary with the degree of cell stimulation: a decrease was observed on treated unstimulated lymphocytes, while p27Kip1increased in dexamethasone-treated cells during stimulation. Our results indicate sequential modifications of the cell-cycle regulation by dexamethasone starting with an action on G1 followed by S-phase control modifications. The protein analysis pinpoints the major complexes concerned: CDK4 and CDK6/cyclin D are mainly involved in G1-phase modifications, while CDK2 and its partner, cyclin E, might be specifically involved in the lengthening of S-phase. The variations observed for p27Kip1might amplify the functional effects of dexamethasone on kinasic complexes. 相似文献
56.
Soybean Lipoxygenase-1 Oxidizes 3Z-Nonenal
: A Route to
4S-Hydroperoxy-2E-Nonenal and Related
Products
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In previous work with soybean (Glycine max), it was reported that the initial product of 3Z-nonenal (NON) oxidation is 4-hydroperoxy-2E-nonenal (4-HPNE). 4-HPNE can be converted to 4-hydroxy-2E-nonenal by a hydroperoxide-dependent peroxygenase. In the present work we have attempted to purify the 4-HPNE-producing oxygenase from soybean seed. Chromatography on various supports had shown that O2 uptake with NON substrate consistently coincided with lipoxygenase (LOX)-1 activity. Compared with oxidation of LOX's preferred substrate, linoleic acid, the activity with NON was about 400- to 1000-fold less. Rather than obtaining the expected 4-HPNE, 4-oxo-2E-nonenal was the principal product of NON oxidation, presumably arising from the enzyme-generated alkoxyl radical of 4-HPNE. In further work a precipitous drop in activity was noted upon dilution of LOX-1 concentration; however, activity could be enhanced by spiking the reaction with 13S-hydroperoxy-9Z,11E-octadecadienoic acid. Under these conditions the principal product of NON oxidation shifted to the expected 4-HPNE. 4-HPNE was demonstrated to be 83% of the 4S-hydroperoxy-stereoisomer. Therefore, LOX-1 is also a 3Z-alkenal oxygenase, and it exerts the same stereospecificity of oxidation as it does with polyunsaturated fatty acids. Two other LOX isozymes of soybean seed were also found to oxidize NON to 4-HPNE with an excess of 4S-hydroperoxy-stereoisomer. 相似文献
57.
D. J. Eaves J. Grove W. Staudenmann P. James R. K. Poole S. A. White l. Griffiths & J. A. Cole 《Molecular microbiology》1998,28(1):205-216
Cytochrome c552 is the terminal component of the formate-dependent nitrite reduction pathway of Escherichia coli. In addition to four ‘typical’ haem-binding motifs, CXXCH-, characteristic of c-type cytochromes, the N-terminal region of NrfA includes a motif, CWSCK. Peptides generated by digesting the cytochrome from wild-type bacteria with cyanogen bromide followed by trypsin were analysed by on-line HPLC MS/MS in parent scanning mode. A strong signal at mass 619, corresponding to haem, was generated by fragmentation of a peptide of mass 1312 that included the sequence CWSCK. Neither this signal nor the haem-containing peptide of mass 1312 was detected in parallel experiments with cytochrome that had been purified from a transformant unable to synthesize NrfE, NrfF and NrfG: this is consistent with our previous report that NrfE and NrfG (but not NrfF) are essential for formate-dependent nitrite reduction. Redox titrations clearly revealed the presence of high and low mid-point potential redox centres. The best fit to the experimental data is for three n = 1 components with mid-point redox potentials (pH 7.0) of +45 mV (21% of the total absorbance change), ?90 mV (36% of the total) and ?210 mV (43% of the total). Plasmids in which the lysine codon of the cysteine–lysine motif, AAA, was changed to the histidine codon CAT (to create a fifth ‘typical’ haem c-binding motif), or to the isoleucine and leucine codons, ATT and CTT, were unable to transform a Nrf? deletion mutant to Nrf+ or to restore formate-dependent nitrite reduction to the transformants. The presence of a 50 kDa periplasmic c-type cytochrome was confirmed by staining proteins separated by SDS–PAGE for covalently bound haem, but the methyl-viologen-dependent nitrite reductase activities associated with the mutated proteins, although still detectable, were far lower than that of the native protein. The combined data establish not only that there is a haem group bound covalently to the cysteine–lysine motif of cytochrome c552 but also that one or more products of the last three genes of the nrf operon are essential for the haem ligation to this motif. 相似文献
58.
Grove S Wiik-Nielsen CR Lunder T Tunsjø HS Tandstad NM Reitan LJ Marthinussen A Sørgaard M Olsen AB Colquhoun DJ 《Diseases of aquatic organisms》2010,93(1):51-61
Previously undocumented phenotypical and genetic variation was identified amongst isolates of Moritella viscosa collected from various geographical locations and from different fish species. The studied isolates could be split into 2 major phenotypically and genetically different clusters, one of which was consistent with the species type strain (NCIMB 13548). Isolates consistent with the type strain originated exclusively from Atlantic salmon farmed in Norway, Scotland and the Faroe Isles, although a single isolate from farmed Norwegian cod clustered closely with this group. The 'variant' cluster comprised isolates originating from Norwegian farmed rainbow trout, Icelandic farmed rainbow trout and salmon, Canadian farmed (Atlantic) salmon, Icelandic lumpsucker and only exceptionally from Norwegian salmon. With the exception of the single aforementioned cod isolate, all isolates from Norwegian farmed cod belonged to the variant cluster. Phenotypically, the clusters could be absolutely separated only by elevated haemolytic activity in the variant strain, although approximately half of these isolates also produced acid from mannose, in contrast to the typical (type) strain. While 16S rRNA gene sequencing was unable to separate the 2 clusters, Western blot analyses, plasmid profile analysis, pulsed field gel electrophoresis and gyrB gene sequence analysis produced clusters consistent with the phenotypic data. Macroscopically and histologically the disease in rainbow trout caused by the variant strain was consistent with that previously described in Atlantic salmon. The results of the present study may indicate a degree of host specificity of the typical strain for Atlantic salmon. 相似文献
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Studies on the digestion process in fish can elucidate some aspects of nutritional physiology. The movements of food items in the alimentary tract are observed using X‐radiography techniques, and nutrient absorption along the alimentary tracts (expressed as relative percentage absorption gradient) is calculated based on the ash contents of adjacent samples. Apparent digestibility coefficient (ADC) values for protein (80–94%), lipid (90–97%), carbohydrate (80.5%) and energy (85–96%) calculated from laboratory‐fed whiting were comparable with those for other fish fed suitable diets. Considerable proportions of all nutrients were absorbed in the short region (anterior intestine/pyloric caeca) but active absorption continued for all nutrients in transit along the longer middle and posterior intestinal segments. In wild whiting samples, the estimated ADC values were protein (65%), lipid (81%) and energy (65%) in passage from the stomach to the rectal region. It was not possible to ascertain the prey in intestinal samples, which probably contained a mixture of species. Sprats and brown shrimps probably dominated the diet, based on biochemical analysis of stomach contents, but polychaetes and other crustaceans could have made a minor contribution. 相似文献