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Julia Antongiovanni Joselevitch Thiago Henrique Moroni Vargas Lidia Hildebrand Pulz Karine Germano Cadrobbi Greice Cestari Huete Adriana Tomoko Nishiya Silvia Regina Kleeb José Guilherme Xavier Ricardo De Francisco Strefezzi 《Veterinary and comparative oncology》2023,21(3):401-405
Mast cell tumour (MCT) is one of the most frequent skin tumours in dogs. Due to their unpredictable biological behaviour, MCTs often cause several therapeutic frustrations, leading to investigation regarding prognostic markers. Lysyl oxidase (LOX) is an enzyme that promotes extracellular matrix stability and contributes to cell migration, angiogenesis and epithelial-mesenchymal transition. Its expression positively correlates with poor prognoses in several human and canine mammary cancers. The aim of this study was to characterise the immunohistochemical expression of LOX in MCT samples and compare it with histological grading and post-surgical survival. Twenty-six tumours were submitted to immunohistochemistry for LOX expression evaluation. All samples were positive for LOX, with variable percentages of cytoplasmic and nuclear positivity. Cytoplasmic positivity was significantly higher in high-grade MCTs (P = .0297). Our results indicate that high expression of cytoplasmic LOX in neoplastic mast cells is an indicator of poor prognosis for canine cutaneous MCTs. 相似文献
105.
Seedlings of four populations each of Pinus pinaster, P. halepensis, P. canariensis and P. pinea were grown in controlled conditions to evaluate both inter- and intra-specific differences in response to watering. We submitted half of the plants to a moderate water stress and after 22 weeks, we recorded height, stem diameter and root, stem and leaves dry weight. Patterns and amounts of phenotypic changes, including changes in biomass allocation, were analysed. We found a scant response in P. canariensis, P. pinaster and P. halepensis presented high population divergence for phenotypic changes, and P. pinea showed marked allocational shifts and no population divergence. The phenotypic changes observed within species are interpreted as a plastic response. The variation encountered within P. halepensis and P. pinaster may be indicative of specialisation to either resource-rich or resource-poor habitats, being populations from favourable sites more plastic. P. pinea exhibited a very uniform plastic response, indicating generalist behaviour. 相似文献
106.
Johannes?EichhornEmail author Regina?Icke Ansgar?Isenberg Uwe?Paar Egbert?Sch?nfelder 《European Journal of Forest Research》2005,124(4):335-347
The evaluation uses the longest available time series for beech and oak defoliation in Germany. The data from Hesse, starting
from 1984, show a typical pattern: for the first 12 years, a continuous increase in defoliation was observed ranging from
an average value of 14% in 1984 to a peak value of 30%. This was followed by a subsequent decrease in the loss of foliage
accompanied by a high variability, until the last monitoring in 2003, where an average value of 25% defoliation was observed.
For both tree species, the years of trend reversal were identical. The same pattern was observed in the German federal states:
Rhineland-Palatinate, North Rhine-Westphalia, and Bavaria. The year of trend reversal was identical in Hesse and Rhineland-Palatinate.
In North Rhine-Westphalia, it occurred 1 year earlier and in Bavaria 3 years earlier. Whereas defoliation trends were clearly
demonstrated, tree mortality did not appear on a large scale. The sample trees were grouped into four discrete clusters according
to their annual defoliation values from 1984 to 2003. In 1996, the clusters represent 15, 25, 35, and 50% defoliation values.
Regarding beech in Hesse, there was no overlap in the defoliation curves observed among the different clusters. These four
clusters having different degrees of defoliation over the whole time span of 20 years were used for a further detailed statistical
analysis. For discrete variables like crown spacing and—in the case of beech—fruit bearing, mosaic plots were applied in order
to visualize relations of low dimensional contingency tables, with defoliation trends being used as the response variable.
The data show for beech a very clear relation between defoliation and age, relative crown spacing, stand composition, and
fruit bearing. Regarding oak, besides age and relative crown spacing, the years with significant appearance of biotic stress
factors—leaf eating insects—show a clear relation to trends of defoliation. The statistical model used in this study—logistic
regression—allows applying a multinomial response variable and a number of continuous or categorical explanatory variables.
With this approach, an iterative optimized selection of effect variables was used to test the relevance of different variables
on the defoliation pattern of the same four clusters mentioned above. For this, the variables were grouped in an iterative
process with five steps, starting with a few basic variables of tree and site information, and ending with a total of more
than 20 variables in the fifth step. The process selects first the variables which are of significance on the defoliation,
and calculates the possible errors in the grouping of the different trees to the four clusters. In this analysis of beech,
the basic tree and stand variables: age, relative crown spacing, stand composition and fruit bearing proved to be the most
relevant group of parameters, with the other variables explaining the variation of defoliation only to a minor extent. More
complex model levels do not change any basic selected variables; however, Cation Exchange Capacity (CEC), C/N-ratio, Al- and
Ca-proportion of CEC are additionally selected and give a hint of the relevance of soil conditions. Regarding beech, the errors
of the statistical model are lower compared to oak. 相似文献
107.
Quandt SA Vitolins MZ Smith SL Tooze JA Bell RA Davis CC DeVellis RF Arcury TA 《Public health nutrition》2007,10(5):524-532
OBJECTIVE: To compare the validity of a modified Block food-frequency questionnaire (FFQ), a picture-sort administration of the FFQ (PSFFQ) and a meal pattern-based questionnaire (MPQ) in a multi-ethnic population of low socio-economic status (SES). DESIGN: Participants completed six 24-hour dietary recalls (24HR) over six months; the FFQ, PSFFQ and MPQ were completed in random order in the subsequent month. Instruments were interviewer-administered. The PSFFQ and MPQ were developed in formative research concerning difficulties for older adults in responding to standard food-frequency instruments. SETTING: Rural North Carolina, USA.Subjects One hundred and twenty-two African American, Native American and white adults aged > or = 65 years, with approximately one-third in each ethnic group. Inclusion criteria included education < or = 12 years and income < or = 150% of national poverty level or Medicaid recipient. RESULTS: Comparing median intakes from the average of the 24HR with the three diet assessment instruments, the MPQ tended to overestimate intakes compared with the FFQ and PSFFQ. Correlations among nutrients obtained by the 24HR and the other three instruments were generally statistically significant and positive. Across nutrients, the PSFFQ was most highly correlated with the 24HR for women, while the FFQ was most highly correlated with the 24HR for men. CONCLUSIONS: Dietary assessments using 24HR and FFQ were similar to results reported elsewhere, although correlations between 24HR and FFQ were somewhat lower. Interviewer-administered dietary assessments should be used with caution to evaluate dietary intake among older adults with low SES. Gender differences and the lower correlations should be investigated more thoroughly to assist in choosing dietary assessment instruments for this population. 相似文献
108.
Fiorani M Accorsi A Blasa M Diamantini G Piatti E 《Journal of agricultural and food chemistry》2006,54(21):8328-8334
In this study we investigated some biological properties of flavonoids recovered in the aqueous (AqE) and ether (EtE) extracts from four Italian multifloral honeys. In particular, a cell-free assay was employed to detect direct reduction of ferricyanide, whereas an assay using intact human erythrocytes was used to measure the ability to donate electrons to a trans-plasma membrane oxidoreductase. It was found that the AqE displays greater "in vitro" ferricyanide-reducing activity than the EtE but, unlike the latter, is virtually ineffective in the cell-based assay. Uptake studies employing high-performance liquid chromatography/mass spectrometry (HPLC/MS) showed that the different results were explained by the inability of AqE components to cross the erythrocyte plasma membrane and by the excellent uptake of EtE flavonoids, which, once within the cell, donate electrons to the membrane oxidoreductase to efficiently reduce extracellular oxidants. The latter property appears to depend on the content of ether-soluble flavonoids in the starting honeys. 相似文献
109.
Fumagalli F Rossoni M Iriti M di Gennaro A Faoro F Borroni E Borgo M Scienza A Sala A Folco G 《Journal of agricultural and food chemistry》2006,54(15):5344-5349
Polyphenolic grapevine components involved in plant resistance against pathogens possess various pharmacological properties that include nitric oxide (NO)-dependent vasodilation and anti-inflammatory and free radical scavenging activities, which may explain the protective effect of moderate red wine consumption against cardiovascular disease. The aim of this work was (a) to verify the possibility that preharvest treatments of grapevine with a plant activator, benzo-(1,2,3)-thiadiazole-7-carbothioic acid S-methyl ester (BTH), could lead to an enriched nutraceutical potential of wine and (b) to characterize the profile of metabolites responsible for pharmacological activity. Plant spraying at the end of veraison, with a water suspension of BTH (0.3 mM), led to increased whole anthocyanin content as confirmed by HPLC comparative analysis. Extracts from berry skins of BTH-treated grapevines caused NO-dependent vasorelaxation, with a concentration-response curve that was significantly shifted to the left of the control non-BTH-treated curve. Moreover, 1:1000 dilutions of berry extracts from BTH-treated plants significantly increased basal production of guanosine 3',5'-cyclic monophosphate (cGMP) in human vascular endothelial cells when compared to the corresponding extracts of untreated plants. These results show that BTH treatment increases anthocyanin content of grape extracts, as well as their ability to induce NO-mediated vasoprotection. No increase of anthocyanin content was observed in the wine extracts from BTH-treated vines. It is concluded that BTH treatment could be exploited to increase the nutraceutical potential of grapes. 相似文献
110.
Hvistendahl M 《Science (New York, N.Y.)》2012,335(6065):153-154