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991.
Falchi A Dantas-Torres F Lorusso V Malia E Lia RP Otranto D 《Experimental & applied acarology》2012,58(2):167-174
The present study was carried out in a protected wooded area, which is part of the Parco Regionale Gallipoli Cognato Piccole Dolomiti Lucane, one of the most important ecological reserves in southern Italy. From April 2010 to April 2011, 212 birds, comprising 22 species from 12 families, were captured and examined for ticks. A total of 75 (35.4?%) birds were found infested by ticks, with 451 ticks being collected. All ticks were identified as Ixodes ricinus, of which 241 (53.4?%) were larvae and 210 nymphs (46.6?%). The highest intensity of infestation was found in April 2010, when 117 ticks were retrieved on 25 birds. No ticks were found on birds (n?=?5) netted in December 2010. High infestation rates were recorded on blackbirds (Turdus merula) (90 %; 29 birds examined) and on mistle thrushes (Turdus viscivorus) (100?%; 2 birds examined). The highest intensity of infestation by larvae was found on wrens (5.6 larvae/bird) and by nymphs on mistle thrushes (11.5 nymphs/bird). Temperature and number of hours of light showed to influence the activity of larvae and nymphs. These data support the notion that birds may be responsible for the heterogeneous distribution of I. ricinus in Europe, thus playing a role in the epidemiology of certain tick-borne pathogens. 相似文献
992.
Yu M Henning R Walker A Kim G Perroy A Alessandro R Virador V Kohn EC 《Journal of cellular and molecular medicine》2012,16(10):2369-2378
Recent work identified L‐asparaginase (L‐ASP) as a putative therapeutic target for ovarian cancer. We suggest that L‐ASP, a dysregulator of glycosylation, would interrupt the local microenvironment, affecting the ovarian cancer cell—endothelial cell interaction and thus angiogenesis without cytotoxic effects. Ovarian cancer cell lines and human microvascular endothelial cells (HMVEC) were exposed to L‐ASP at physiologically attainable concentrations and subjected to analyses of endothelial tube formation, invasion, adhesion and the assessment of sialylated proteins involved in matrix‐associated and heterotypic cell adhesion. Marked reduction in HMVEC tube formation in vitro, HMVEC and ovarian cancer cell invasion, and heterotypic cell‐cell and cell‐matrix adhesion was observed (P < 0.05–0.0001). These effects were associated with reduced binding to ß1integrin, activation of FAK, and cell surface sialyl LewisX (sLex) expression. No reduction in HMVEC E‐selectin expression was seen consistent with the unidirectional inhibitory actions observed. L‐ASP concentrations were non‐toxic to either ovarian cancer or HMVEC lines in the time frame of the assays. However, early changes of autophagy were observed in both cell types with induction of ATG12, beclin‐1, and cleavage of LC‐3, indicating cell injury did occur. These data and the known mechanism of action of L‐ASP on glycosylation of nascent proteins suggest that L‐ASP reduces of ovarian cancer dissemination and progression through modification of its microenvironment. The reduction of ovarian cancer cell surface sLex inhibits interaction with HMVEC and thus HMVEC differentiation into tubes, inhibits interaction with the local matrix reducing invasive behaviour, and causes cell injury initiating autophagy in tumour and vascular cells. 相似文献
993.
E Capra R Beretta V Parazzi M Viganò L Lazzari A Baldi R Giordano 《Proteome science》2012,10(1):46-14
ABSTRACT: BACKGROUND: Human mesenchymal stem cells (hMSC) have recently attracted the attention because of their therapeutic potential in the novel context of regenerative medicine. The safety of these new and promising cellular products should be carefully defined before they can be used in the clinical setting. The protein expression profile of these cells might reveal potential hazards associated with senescence and tumoral transformation which may occur during culture. Proteomic is a valuable tool for hMSC characterization and identification of possible changes during expansion. RESULTS: We used SELDI-ToF-MS (Surface Enhanced Laser Desorption/Ionization-Time Of Flight-Mass Spectrometry) to evaluate the presence of stable molecular markers in adipose tissue-derived mesenchymal stem cells (AD-MSC) produced under conditions of good manufacturing practices (GMP). Proteomic patterns of cells prepared were consistent, with 4 up-regulated peaks (mass-to-charge ratio (m/z) 8950, 10087, 10345, and 13058 respectively) through subculture steps (P0-P7) with similar trend in all of the three donors. Among the differentially expressed proteins found in the cytoplasmic and nuclear fractions, a cytoplasmic 10.1 kDa protein was upregulated during culture passages and was identified as S100A6 (Calcyclin). CONCLUSIONS: This study suggests for the first time that common variation could occur in ADMSC from different donors, with the identification of S100A6, protein prevalently related to cell proliferation and cell culture condition. These results support the hypothesis of common proteomic changes during MSCs expansion and could give important insight in the knowledge of molecular mechanisms intervening during MSC expansion. 相似文献
994.
Andrea Riccardo Filippi Filippo Alongi Patrizia Ciammella Berardino De Bari Pierfrancesco Franco Lorenzo Livi 《Reports of Practical Oncology and Radiotherapy》2012,17(5):259-261
AimTo briefly review history, structure, past events and future projects of AIRO (Associazione Italiana Radioterapia Oncologica) young group (AIRO Giovani), focusing on its specific commitment to multidisciplnary networking among junior clinical oncologists at a national and international level.BackgroundAIRO Giovani is a part of AIRO composed by members under 40 years old. Its main activities are scientific and educational meetings dedicated to young Italian radiation oncologists and collaborative research projects.Materials and MethodsAIRO Giovani structure, events organized and supported by AIRO giovani as well as scientific activities are here reported from its creation in 2007 up to current days.ResultsAIRO Giovani group was able to create a consolidated network between Italian junior radiation oncologists, while opening the possibility to collaborate with junior groups of other national scientific societies in the field of oncology and with ESTRO young members. Scientific projects carried out by the group have been successful and will be further implemented in next years.ConclusionsAIRO Giovani is still in its infancy, but its early positive experience supports the creation and development of young groups within national radiation oncology societies. 相似文献
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998.
Riccardo A. A. Muzzarelli 《Carbohydrate polymers》1985,5(6):461-472
The degree of acetylation of chitosan can be determined in acetic acid solutions (~0·01m) containing 1 g dry chitosan per litre by first derivative ultraviolet spectrophotometry at 199 nm. At this wavelength, the N-acetylglucosamine absorbance readings are linearly dependent on concentration and are not influenced by the presence of acetic acid. Correction factors for the contribution of glucosamine in highly deacetylated chitosans can be easily derived. Typical results for the chitosan of Euphausia superba are: degree of acetylation, 42·6; relative standard deviation, 1·3%; confidence limits, ±0·7. This method is simpler, more precise and faster than the infrared method. Sonication of chitosan solutions leads to immediate chain degradation and to detectable deacetylation after more prolonged periods of time, especially when the pH is 1·0. 相似文献
999.
Brush cells of the mouse gallbladder 总被引:3,自引:0,他引:3
Summary The brush cells (BC) of the mouse gallbladder were studied using light and electron microscopy (transmission and scanning) to determine their shape and distribution. Specimens were fixed in glutaraldehyde and postfixed in ferrocyanide-reduced osmium tetroxide. BC selectively stained with toluidine blue could be identified by means of light microscopy and subsequently studied in serial semithin and ultrathin sections. The results revealed that the shape of the BC is flask-like. A slender, occasionally branched cytoplasmic process emerges from the bulk cell body and extends through the basal region of neighboring epithelial elements to the basement membrane. Examination of the entire gallbladder epithelial surface by scanning electron microscopy revealed that the BC are numerous in the neck region of the organ but only scanty or even absent in wide areas of the corpus region. Their number increases again in the fundic region. These results demonstrate a preferential regional distribution of BC in the gallbladder, which is discussed in relation to a possible functional significance of the BC. 相似文献
1000.
Riccardo A.A. Muzzarelli Fabio Tanfani Monica Emanuelli Dante P. Pace Enrico Chiurazzi Mario Piani 《Carbohydrate research》1984,126(2):225-231
N-(Carboxymethyl)chitosan was subjected to sulfation in a mixture of concentrated sulfuric acid (oleum) and N,N-dimethylformamide, under anhydrous conditions. The resulting product contained 11% of sulfur and degree of substitution: N-acetyl, 42%; N-carboxymethyl, 58%; and sulfate, 100%. Sonication of the sulfated N-(carboxymethyl)chitosan gave two main fractions whose molecular weights were 39,000 and 80,000. In human blood, complexes of sulfated N-(carboxymethyl) chitosan and antithrombin inhibited both thrombin and factor Xa, and produced neither hemolysis nor alterations in erythrocytes and lymphocytes. Sulfated N-(carboxymethyl)chitosan is therefore proposed as a blood anticoagulant. 相似文献