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221.
Topographic and functional imaging hold a key position in endocrine oncology. In vivo somatostatin receptor scintigraphy using Indium-111 labeled DTPA-octreotide, a tracer with preferential affinity for the somatostatin receptor subtype 2 (sst2), is the gold-standard for initial diagnosis of gastroenteropancreatic neuroendocrine tumours (GEPNETs). Due to the detection limits of scintigraphy, other metabolic imaging modalities are required. Positron emission topography (PET) offers whole body scanning, facilitates tumour localization, and assesses the metastasis statement of the tumour. 18F-FDG is the most frequent radiotracer used in clinical practice because of its availability, but its interest is demonstrated only in undifferentiated GEPNETs. More recently, 18F-DOPA PET showed a high sensitivity in particular in carcinoid tumours detection. PET using different 68Ga-labeled-somatostatin analogs with high affinity for sst2 displayed better results than SRS in GEPNETs primary tumour and metastasis detection, especially when fusion with TDM images was performed. Using similar metabolic targets, peptide receptor radionuclide therapy (PRRT) with 177Lu-octreotate and 90Y-DOTA-TOC, is indicated in disseminated GEPNETs forms with an efficiency of 30 % and a minor toxicity. 相似文献
222.
Banaz-Yaşar F Steffen G Hauschild J Bongartz BM Schumann GG Ergün S 《Histochemistry and cell biology》2010,134(6):581-589
Long interspersed nuclear element-1 (LINE-1, L1) is a retrotransposon which affects the human genome by a variety of mechanisms.
While LINE-1 expression is suppressed in the most somatic human cells, LINE-1 elements are activated in human cancer. Recently,
high accumulation of LINE-1-encoded ORF1p and ORF2p in endothelial cells of mature human blood vessels was described. Here,
we demonstrate that LINE-1 de novo retrotransposition events lead to a reduction of endothelial cell proliferation and migration
in a porcine aortic endothelial (PAE) cell model. Cell cycle studies show a G0/G1 arrest in PAE cells harboring LINE-1 de
novo retrotransposition events. Remarkably, in in situ analysis LINE-1-encoded ORF2p was not detectable in tumor blood vessels
of different human organs while vascular endothelial cells of corresponding normal organs strongly expressed LINE-1 ORF2p.
Quantitative RT-PCR analysis revealed that LINE-1 de novo retrotransposition influences selectively the expression of some
angiogenic factors such as VEGF and Tie-2. Thus, our data suggest that LINE-1 de novo retrotransposition events might suppress
angiogenesis and tumor vascularisation by reducing the angiogenic capacity of vascular endothelial cells. 相似文献
223.
224.
Oliveira TG Carvalho-Costa FA Gomes TF Sarquis O Sposina R Lima MM 《Memórias do Instituto Oswaldo Cruz》2010,105(8):1057-1060
The aim of this work was to study the interaction between Trypanosoma cruzi-1 and Triatoma brasiliensis. A group of 1st instar nymphs was initially fed on T. cruzi-infected mice and a control group was fed on uninfected mice. From the second feeding onwards, both groups were otherwise fed on non-infected mice. The resulting adults were grouped in pairs: infected male/uninfected female, uninfected male/infected female, infected male and female and uninfected male/uninfected female. The infection affected only the 1st instar nymphs, which took significantly more time to reach the 2nd instar than uninfected nymphs. The differences in the molting time between the infected and uninfected nymphs from the 2nd to the 5th instars were not statistically significant. Both groups presented similar rates of nymphal mortality and reproductive performance was not significantly affected by infection in any of the treatments. 相似文献
225.
Muharrem Bitiren Ali Ziya Karakilcik Mustafa Zerin Ilyas Ozardalı Sehabettin Selek Yaşar Nazlıgül Abdullah Ozgonul Davut Musa Ali Uzunkoy 《Biological trace element research》2010,136(1):87-95
Ulcerative colitis increases oxidative damage accompanied by production of free oxygen radicals. Selenium (Se) and vitamin
E are two natural antioxidants. The present study was undertaken to investigate the possible protective role of Se and vitamin
E combination in experimental colitis induced by acetic acid (AA) in rats. This study was carried out on three groups, namely
the first (control), the second (experimental colitis group, 2 ml 5% acetic acid), and the third groups (2 ml 5% acetic acid,
vitamin E (100 mg/kg body weight (bw)) plus Se (0.2 mg/kg bw)). The activities of catalase (CAT), prolidase (PRS), myeloperoxidase
(MPO), total antioxidant capacity (TAC), total oxidant status (TOS), oxidative stress index (OSI), total thiol (T-SH) were
determined in plasma and colon samples. Macroscopic and microscopic damages in colon were increased by AA treatment (p < 0.01 and p < 0.01, respectively), whereas they were decreased by selenium and vitamin E treatment (p < 0.05 and p < 0.01, respectively). The activities of CAT and PRS in the plasma and colon were significantly affected (p < 0.05 and p < 0.01) by treatment of AA, Se, and vitamin E. MPO activity in colon was increased (p < 0.01) by AA treatment and decreased (p < 0.05) by Se and vitamin E administration. The values of TOS and OSI in plasma were increased (p < 0.5) by AA. The TAC and T-SH in colon were decreased (p < 0.05) by AA and increased (p < 0.05) by Se and vitamin E. Based upon these results, Se and vitamin E may play an important role in preventive indication
of the oxidative damage associated by acetic acid caused inflammation. 相似文献
226.
The morphology, anatomy and distribution of glandular trichomes on the aerial organs of Salvia argentea L. has been investigated. Two morphologically distinct types of glandular trichomes were determined. Capitate glandular trichomes
forming a base 1–7 celled, a stalk 1–5 celled or no stalk and a head uni- or bicellular had various types. In capitate trichomes,
the neck cell that has an important role especially for xeroformic plants, acting to prevent the backflow of secreted substance
through the apoplast has been distinctively observed in the investigated species. The capitate trichomes were present abundantly
on all aerial organs of S. argentea. Peltate glandular trichomes had a large secretory head forming 1–5, 8 central and 8–10, 12, 14 peripheral cells. Peltate
trichomes are present on all aerial organs, except petiole, being the most abundant on calyx and corolla. Results were shown
by tables and photographs. 相似文献
227.
Raşit Urhan 《Biologia》2010,65(1):92-98
In this study, two new species of zerconid mites, Zercon domanicensis sp. n. and Z. yusufi sp. n., are described and illustrated on the basis of materials collected from Turkey. The similarities and differences between
the species were discussed. 相似文献
228.
Parasitism of plants by other plants provides an exceptional opportunity for investigating correlative nutritional relationships.
Because of lacking a usual plant-root sytem capable of active uptake, the best correlation for predicting the concentrations
of elements in parasitic plants is often those in the host plants. This study, therefore, mainly focuses on determination
of i) mineral nutrient partitioning between hemi-parasitic white berry mistletoe (Viscum album L. subsp. album) and four of its deciduous hosts growing in different habitats namely wetland and semi-arid and ii) effects of these habitat
types on nutrient absorption. During the research, leaf samples of both hemi-parasites and their host plants were chemically
analysed, mistletoes on each host plants were counted and the results were considered statistically. Concentrations of some
elements (N, P, K, Na, S, Cu, Zn) were higher in mistletoe whereas some others (Ca, Mg, Fe, Mn and B) were higher in the hosts
(p< 0.05). Habitat type was also determined to be effective in host-parasite systems. Revealing information about nutritional
interactions between multi-host hemi-parasites and their host plants is a useful tool to understand their functions in ecosystems,
population-community dynamics and their co-evolution process. 相似文献
229.
M. Çankaya M. Şişecioğlu Ö. Barış M. Güllüce H. Özdemir 《Applied Biochemistry and Microbiology》2010,46(1):57-60
Bovine lactoperoxidase (LPO) was purified from skimmed milk using amberlite CG-50-H+ resin, CM sephadex C-50 ion-exchange chromatography, and sephadex G-100 gel filtration chromatography. Lactoperoxidase was purified 20.45-fold with a yield of 28.8%. Purity of enzyme checked by sodium dodecyl sulphate-polyacrylamide gel electrophoresis method and a single band was observed. K m was 0.25 mM at 20°C, V max value was 7.95 μmol/ml min at 20°C (pH 6.0). Antibacterial study was done by disk diffusion method of Kirby-Bauer using Mueller-Hinton agar medium with slight modification. Bovine LPO showed high antibacterial activity in 100 mM thiocyanate-100 mM H2O2 medium for some bacteria (Brevibacillus centrosaurus, B. choshinensis, B. lyticum, Cedecea davisae, Chryseobacterium indoltheticum, Clavibacter michiganense pv. insidiosum, Kocuria erythromyxa, K. kristinae, K. rosea, K. varians, Paenibacillus validus, Pseudomonas syringae pv. populans, Ralstonia pickettii, Rhodococcus wratislaviensis, Serratia fonticola, Streptomyces violaceusniger, Vibrio cholerae-nonO1) respectively, and compared with well known antibacterial substances (levofloxacin, netilmicin). LPO system has inhibition effects on all type bacteria and concentration is really important such as LPO-100 mM thiocyanate-100 mM H2O2 system was proposed as an effective agent against many factors causing several diseases. 相似文献
230.
İbrahim Horo Erdal Bedir Angela Perrone Fevzi Özgökçe Sonia Piacente Özgen Alankuş-Çalışkan 《Phytochemistry》2010,71(8-9):956-963
Six cycloartane-type triterpene glycosides were isolated from Astragalus icmadophilus along with two known cycloartane-type glycosides, five known oleanane-type triterpene glycosides and one known flavonol glycoside. The structures of the six compounds were established as 3-O-[α-L-arabinopyranosyl-(1 → 2)-O-3-acetoxy-α-L-arabinopyranosyl]-6-O-β-D-glucopyranosyl-3β,6α,16β,24(S),25-pentahydroxycycloartane, 3-O-[α-L-rhamnopyranosyl-(1 → 2)-O-α-L-arabinopyranosyl-(1 → 2)-O-β-D-xylopyranosyl]-6-O-β-D-glucopyranosyl-3β,6α,16β,24(S),25-pentahydroxy cycloartane, 3-O-[α-L-arabinopyranosyl-(1 → 2)-O-3,4-diacetoxy-α-L-arabinopyranosyl]-6-O-β-D-glucopyranosyl-3β,6α,16β,24(S),25-pentahydroxycycloartane, 3-O-[α-L-arabinopyranosyl-(1 → 2)-O-3-acetoxy-α-L-arabinopyranosyl]-6-O-β-D-glucopyranosyl-3β,6α,16β,25-tetrahydroxy-20(R),24(S)-epoxycycloartane, 3-O-[α-L-arabinopyranosyl-(1 → 2)-O-β-D-xylopyranosyl]-6-O-β-D-glucopyranosyl-3β,6α,16β,24α-tetrahydroxy-20(R),25-epoxycycloartane, 3-O-[α-L-rhamnopyranosyl-(1 → 2)-O-α-L-arabinopyranosyl-(1 → 2)-O-β-D-xylopyranosyl]-6-O-β-D-glucopyranosyl-3β,6α,16β,24α-tetrahydroxy-20(R),25-epoxycycloartane by the extensive use of 1D- and 2D-NMR experiments along with ESIMS and HRMS analysis.The first four compounds are cyclocanthogenin and cycloastragenol glycosides, whereas the last two are based on cyclocephalogenin as aglycone, more unusual in the plant kingdom, so far reported only from Astragalus spp. 相似文献