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1.
The trans-lycopene content of fresh tomato homogenates was assessed by means of the laser photoacoustic spectroscopy, the laser optothermal window, micro-Raman spectroscopy, and colorimetry; none of these methods require the extraction from the product matrix prior to the analysis. The wet chemistry method (high-performance liquid chromatography) was used as the absolute quantitative method. Analytical figures of merit for all methods were compared statistically; best linear correlation was achieved for the chromaticity index a* and chroma C*.  相似文献   
2.
The first step in understanding gut microbial ecology is determining the presence and potential niche breadth of associated microbes. While the core gut bacteria of adult honey bees is becoming increasingly apparent, there is very little and inconsistent information concerning symbiotic bacterial communities in honey bee larvae. The larval gut is the target of highly pathogenic bacteria and fungi, highlighting the need to understand interactions between typical larval gut flora, nutrition and disease progression. Here we show that the larval gut is colonized by a handful of bacterial groups previously described from guts of adult honey bees or other pollinators. First and second larval instars contained almost exclusively Alpha 2.2, a core Acetobacteraceae, while later instars were dominated by one of two very different Lactobacillus spp., depending on the sampled site. Royal jelly inhibition assays revealed that of seven bacteria occurring in larvae, only one Neisseriaceae and one Lactobacillus sp. were inhibited. We found both core and environmentally vectored bacteria with putatively beneficial functions. Our results suggest that early inoculation by Acetobacteraceae may be important for microbial succession in larvae. This assay is a starting point for more sophisticated in vitro models of nutrition and disease resistance in honey bee larvae.  相似文献   
3.
Vojvodic S  McCreadie JW 《Mycologia》2007,99(3):412-420
We examined the growth and development of the trichomycete Smittium culisetae (Harpellales: Legeriomycetaceae) in the larval hosts Simulium vittatum Zetterstedt (Diptera: Simuliidae) and Aedes aegypti (L.) (Diptera: Culicidae) at three temperatures, 17, 22 and 30 C. Trichospore maturation of Sm. culicetae external to the host as well as the ability of these trichospores to colonize new hosts also was investigated. Although the development of Sm. culisetae varied with both temperature and host there was a pattern of maximum trichospore production at 48-72 h postinoculation. In addition thalli under laboratory conditions are capable of spore production after extraction from a host and these trichospores can colonize new hosts. Furthermore this was noted to occur in both host species. These results suggest that synchrony between host and symbiont development is not as tightly coupled as previously assumed.  相似文献   
4.
Gangliosides (GGs), involved in malignant alteration and tumor progression/invasiveness, are considered as tumor biomarkers or therapeutic targets. Here, we describe the first systematic GG composition characterization in human gliosarcoma versus normal brain tissue using our recently developed mass spectrometry (MS) methods, based on nano-electrospray (nano-ESI), Fourier-transform ion cyclotron resonance (FT-ICR), and chip nano-ESI quadrupole time-of-flight (QTOF), complemented by thin-layer chromatographic (TLC) analysis and quantification. Combined MS enabled detection and structural assignment of 73 distinct GG species: many more than reported so far for investigated gliomas. Apart from the 7.4-times lower total GG content, gliosarcoma contained all major brain-associated species, however, in very altered proportions, exhibiting a highly distinctive pattern: GD3 (48.9%)>GD1a/nLD1>GD2/GT3>GM3>GT1b>GM2>GM1a/GM1b/nLM1>LM1>GD1b>GQ1b. MS also revealed abundant O-Ac-GD3; its sequencing provided structural evidence to postulate a novel O-Ac-GD3 isomer O-acetylated at the inner Neu5Ac-residue, previously not structurally confirmed. The high sensitivity and mass accuracy permitted the assignment of unusual minor species: GM4, Hex-HexNAc-nLM1, Gal-GD1, Fuc-GT1, GalNAc-GT1, O-Ac-GM3, di- O-Ac-GD3O-Ac-GD3, and O-Ac-GT3, not previously reported as glioma-associated. The gliosarcoma-expressed GA2 might represent a marker distinguishing astrocytic from oligodendroglial tumors. This is, to our knowledge, so far the most complete GG composition characterization of certain glioma, which demonstrates that our MS-based approach could provide essential structural information relevant to glycosphingolipid role(s) in brain tumor biology, differential diagnosis/prognosis and novel treatment concepts.  相似文献   
5.
The aim of this paper was to evaluate the ocular findings in patients with chronic renal failure (CRF) undergoing haemodialysis (HD). In 64 patients undergoing haemodialysis (30 female and 34 male), aged 24-83 years (mean 58 years) on haemodialysis 1-213 months (mean 47 months) complete ocular examination were performed: visual acuity (VA), intraocular pressure (IOP), biomicroscopic examination and fundoscopy. On right eye sixty-nine percent of patents had VA 0.6 or better, and on left eye 84% of patients had VA 0.6 or better. Mean IOP before dialysis was 15 mmHg and after dialysis was 14 mmHg. In 9 patients (14%) we found corneo-conjunctival calcium deposits. No correlation of ocular calcification and parathyroid hormone (PTH) level or calcium and phosphate product were observed. 39 (60%) patients had cataract. Hypertensive vascular changes were seen in 44 (68%) patients and in 6 (7%) patients age-related macular degeneration. Seven patients had diabetes mellitus and in 5 diabetic retinopathy was observed. Patients with CRF or who are receiving HD represent unique group of patients. Pathologic change could be found in many tissue and organs, therefore we suggest ocular examination more frequently in dialysis patients.  相似文献   
6.

Background

Chronic heart failure is an important cause for morbidity and mortality in adults with congenital heart disease (ACHD). While NT-proBNP is an established biomarker for heart failure of non-congenital origin, its value in ACHD has limitations. Asymmetrical dimethylarginine (ADMA) correlates with disease severity and independently predicts adverse clinical events in heart failure of non-congenital origin. Its role in ACHD has not been investigated.

Methods

In 102 patients ADMA and NT-proBNP were measured and related to NYHA class, systemic ventricular function and parameters of cardiopulmonary exercise testing.

Results

In contrast to NT-proBNP ADMA differentiated between NYHA classes I-III. Both, ADMA and NT-proBNP showed a good correlation with parameters of cardiopulmonary exercise testing with comparable receiver-operating characteristic curves for identifying patients with severely limited cardiopulmonary exercise capacity.

Conclusion

ADMA seems to be a better biomarker than NT-proBNP for the assessment of NYHA class and as a good as NT-proBNP for the estimation of maximum exercise capacity in adults with congenital heart disease. Its use in clinical routine should be evaluated.  相似文献   
7.
The method for virus titer determination of avian infectious bursal disease (IBD) live vaccine, developed long before regulatory validation guidelines is a cell culture based biological assay intended for use in vaccine release testing.The aim of our study was to perform a validation, based on fit-for-purpose principle, of an old 50% tissue culture infectious dose (TCID50) method according to Guidelines of the International Cooperation on Harmonization of Technical Requirements for Registration of Veterinary Medicinal Products (VICH).This paper addresses challenges and discusses some key aspects that should be considered when validating biological methods. A different statistical approach and non-parametric statistics was introduced in validation protocol in order to derive useful information from experimental data. This approach is applicable for a wide range of methods.In conclusion, the previous virus titration method had showed to be precise, accurate, linear, robust and in accordance with current regulatory standards, which indicates that there is no need for additional re-development or upgrades of the method for its suitability for intended use.  相似文献   
8.
Red clover, known for its estrogenic activity due to its isoflavones content (biochanin A, genistein, daidzein and formononetin), was inoculated with the arbuscular mycorrhizal fungus Glomus mosseae. Once the symbiotic fungus was well established, plants were harvested and we determined the root and shoot dry weight as well as the P-content. In roots and leaves the levels of biochanin A, genistein, daidzein and formononetin were quantified by reversed-phase HPLC and the estrogenic activity of the leaves was measured by a transactivation assay using a yeast two-plasmid system. Mycorrhization increased the levels of biochanin A in the root and the shoot and reduced the levels of genistein in the shoot of red clover. The levels of the other isoflavones were not affected. The shoot biomass of mycorrhizal plants more than doubled compared with non-mycorrhizal control plants, and this growth-stimulating effect of arbuscular mycorrhiza did not affect the estrogenic activity of red clover. In a control P treatment, the biomass of red clover was greatly enhanced. However, the estrogenic activity was reduced. These results suggest that, in contrast to an enhanced shoot biomass production after P application with a reduced estrogenic activity, with arbuscular mycorrhiza the shoot biomass of red clover can be enhanced without a negative effect on estrogenic activity.  相似文献   
9.
10.
Squids are especially frequent as paratenic hosts of helminth parasites, particularly to those that have elasmobranchs and mammals as final hosts. Among those parasite species, anisakid nematode larvae and cestode plerocercoids are most effectively transferred through the trophic chain by oegopsid squids. A total of 439 short-finned squids, Illex coindetii (245 males, 190 females and 4 unsexed) were sampled in the central part of the eastern Adriatic Sea in order to assess their helminth component community and parasite dynamics with respect to host sex, maturity, seasonality, and feeding behavior. Two larval helminths were isolated, i.e., larvae of Anisakis pegreffii, characterized by molecular tools at the species level, and plerocercoids of Phyllobothrium sp., with prevalences of 30.5% and 2.3%, respectively. Highly significant seasonal variation in diet consumption, congruent with seasonal variation in anisakid intensity, was observed, underlining the tight role of squid prey in the trophic transmission of parasite. Likewise, the highest helminth prevalence and intensity of infection was recorded in autumn, when the fish prey, mostly Maurolicus muelleri, comprised the greatest proportion of diet. This helped to assign the Adriatic broadtail shortfin squid not as a first, but as a second, paratenic host for the anisakid, unlike as suggested previously. The presence of larval A. pegreffii confirms its previously reported zoogeographical distribution in the Mediterranean and Adriatic Seas. The presence of 2 helminths in I. coindetii describes the feeding patterns of the squid, as well as clearly defined and coevolved predator-prey relationships.  相似文献   
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