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91.
92.
NIR-FT-Raman as well as ATR-IR and NIR spectroscopy in combination with efficient chemometric algorithms was applied for rapid determination of piperine in black and white ground pepper and green whole pepper berries as well as pepper oleoresins. Most of the well-resolved Raman signals detected in the spectra of pepper and the related oleoresins can be assigned to piperine, which is known to be the main pungent principle in these products. On the basis of the specific key bands of piperine, also selective Raman mappings were successfully performed to determine the in situ distribution of the alkaloid in the whole green berry and the dried peppercorn as well. It was found that piperine occurs more or less in the whole perisperm of the green fruit. Furthermore, the content and composition of the volatile fraction in various pepper samples were determined by applying the mentioned vibrational spectroscopy techniques. Whereas only NIRS measurements present sufficient reliability to predict the main essential oil substances directly in ground black and white pepper, all spectroscopy methods applied in this study can be used to analyze individual terpenoids in the hydrodistilled oil. It can be assumed that some of the new, efficient vibrational spectroscopy methods have the potential to replace the standard analysis procedures presently applied for the quality control of peppercorns, pepper extracts, and pepper oil.  相似文献   
93.
Looking for potential quality indicators, which could be used in early selection of breeding materials, the structural features of cell wall arabinoxylans (AX) from outer layers of the grain (pooled shorts and bran fractions) were studied in two ryes with diverse breadmaking quality. The successive alkaline extraction of water-unextractable material with saturated Ba(OH)2, followed by water and 1 and 4 M NaOH, resulted in four purified fractions, Ba, BaH, 1Na, and 4Na, respectively, that became water soluble after their isolation. The AX present in these fractions constituted approximately 43, 12, 14, and 4% of their total amount recovered. Moreover, two xylan-enriched fractions, 1Na.P and 4Na.P (arabinose-to-xylose ratios, Ara/Xyl, of 0.07 and 0.19, respectively), were self-precipitated from both NaOH-extractable fractions. Polysaccharides of these fractions, containing mainly xylose, represented approximately 16 and 1% of AX recovered. In the BaH and 1Na, AX coexisted with beta-glucans, which predominated in the former protein-free fraction. On the contrary, hemicelluloses in the 1Na fraction were associated with protein as well. Further fractionation of the water-soluble materials by ammonium sulfate revealed that the parent AX populations in the Ba, BaH, and 1Na were composed of 3-4 subfractions with different degrees of substitution (Ara/Xyl of approximately 0.4, 0.8, and 1.1), whereas 4Na was almost totally built of highly substituted AX (Ara/Xyl of 1.1). Despite a comparable proportion of un-, mono-, and disubstituted xylopyranosyl residues in the chain of Ba(OH)2-extractable AX isolated from both ryes, the 1H NMR and Fourier transform infrared demonstrated the marked differences in their spectral profiles, suggesting different substitution patterns of these dominating polysaccharides. The high molecular weight population present in the Ba fraction also differentiated well two ryes with opposite breadmaking quality.  相似文献   
94.
The influence of procyanidin extract from Japanese quince fruit on the activities of matrix metalloproteinases MMP-2 and MMP-9 secreted to culture medium by human peripheral blood mononuclear cells (PBMC) and by human leukemia HL-60 cells was investigated by gelatin zymography. The extract proved to be an effective inhibitor of the enzymes activities (for MMP-2 and MMP-9 secreted by PBMC IC50 = 16-19 microg extract/mL and 22-25 microg extract/mL, respectively). To identify the most effective components of the extract it was fractionated by means of column chromatography on TSKgel Toyopearl HW-40 (S) bed. The obtained fractions were analyzed by TLC, HPLC, and MALDI-TOF MS. Their antioxidant activity was measured as cation radicals ABTS(.+) scavenging efficiency. The fractions VIII-XIV containing oligomers from trimer to hexamer (and probably higher oligomers) appeared to be the most effective inhibitors of MMP-2 and MMP-9 activity (IC50 value close to 4.6 microg total polyphenols/mL). To the best of our knowledge, it is the first report on gelatinase-inhibitory activity of Japanese quince fruit polyphenol extract. We conclude that polyphenols from Japanese quince can be used in cancer chemoprevention, although further studies are needed to elucidate the mechanisms underlying their biological activities.  相似文献   
95.
96.
Squamous cell carcinomas of sparsely haired skin are relatively common tumors in cats, and these tumors likely exhibit a rapid growth rate. Thus, we evaluated response and duration of response in relation to the Ki67 proliferative reactivity in such tumors. Seventeen cats with confirmed squamous cell carcinomas and treated with an accelerated, hypofractionated electron beam radiation protocol were included in the study. For all of them histologic grading, Ki67 reactivity, response, and disease-free interval (DFI) were evaluated. Response to therapy was excellent (94% complete response rate) with a median DFI of 414 days. Only moderate acute and few long-term adverse effects were seen. Cats with tumors with a low Ki67 reactivity had markedly shorter DFIs than cats with tumors with high Ki67 reactivity. We concluded that an accelerated, hypofractionated electron beam radiation therapy protocol is well suited for feline squamous cell carcinomas. The protocol appears especially efficacious in tumors with a high Ki67 reactivity.  相似文献   
97.
The rate of swelling of barbel Barbus barbus (L.) eggs and of embryonic development increased with temperature (from 12 to 22°C). Survival of embryos decreased during the embryonic development and the highest mortality at each developmental stage occurred at 12 and 22°C. Body malformations in embryos during cleavage and organogenesis were the most frequent at 12, 14 and 22°C. During the embryogenesis, three types of embryonic body malformations were observed: yolk sac oedema, spine curvature and shortening of body. At all temperatures, most of larvae hatched with tail first but at 12 and 22°C significantly more larvae hatched with yolk sac compared to the other temperatures. The highest percentage of normal viable larvae was obtained at 14 and 18°C. Larval malformations and dead larvae were significantly most frequent at 12 and 22°C compared to the other groups. At all temperatures, spine curvatures and yolk sac deformation were the most frequent types of larval deformations.  相似文献   
98.
Avian influenza H9N2 viruses have become panzootic in Eurasia causing respiratory manifestations, great economic losses and occasionally being transmitted to humans. To evaluate the replication properties and compare the different virus quantification methods, four Eurasian H9N2 viruses from different geographical origins were propagated in embryonated chicken egg (ECE) and Madin-Darby canine kidney epithelial cell systems. The ECE-grown and cell culture-grown viruses were monitored for replication kinetics based on tissue culture infectious dose (TCID50), Hemagglutination (HA) test and quantitative real time RT-PCR (qRT-PCR). The cellular morphology was analyzed using immunofluorescence (IF) and cellular ELISA was used to screen the sensitivity of the viruses to amantadine. The Eurasian wild type-H9N2 virus produced lower titers compared to the three G1-H9N2 viruses at respective time points. Detectable titers were observed earliest at 16 h post inoculation (hpi), significant morphological changes on cells were first observed at 32 hpi. Few nucleotide and amino acid substitutions were noticed in the HA, NA and NS gene sequences but none of them are related to the known conserved region that can alter pathogenesis or virulence following a single passage in cell culture. All studied H9N2 viruses were sensitive to amantadine. The G1-H9N2 viruses have higher replication capabilities compared to the European wild bird-H9N2 probably due to their specific genetic constitutions which is prerequisite for a successful vaccine candidate. Both the ECE and MDCK cell system allowed efficient replication but the ECE system is considered as the better cultivation system for H9N2 viruses in order to get maximum amounts of virus within a short time period.  相似文献   
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