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1.
Jovanović I Ugrenović S Antić S Stefanović N Mihailović D 《Microscopy research and technique》2007,70(7):617-627
Psammoma bodies (PBs) are one of many choroids plexus aging changes. The aim of our research was to perform the quantification of PBs' presence in human choroids plexus stroma, as well as to evaluate the characteristics of choroids plexus stroma in cases in which PBs were present. Afterwards, the observations of the histochemical analysis would be confirmed by immunohistochemical analysis. Choroid plexuses of 30 cadavers were used for the histochemical and, choroids plexuses of 15 cadavers in which PBs' presence was confirmed during the histochemical analysis, were used as material for the immunohistochemical analysis. Light microscopy, histochemical, immunohistochemical, and morphometric method were applied during the study. Classification of the cases was performed by cluster analysis. We observed increase of choroids plexus PBs' presence during the aging process. But this increase is not linear. Their presence is the largest in the second cluster that is younger than the third and older than the first. Nuclear morphometric parameters of the stroma in these cases showed that the cellular composition in this cluster is different than in other two and, that contain larger number of lymphoid cells. Immunohistochemical analysis showed PBs' positive reaction on vimentin, CD45R0, and LCA markers, while in their vicinity, as well as inside them, numerous T-cells were observed. So, the presence of CD45R0 and LCA-positive T cells, PBs' positive reaction on the same markers, indirectly connect these cells with PBs' formation process. 相似文献
2.
Diana Meter Anita Racetin Katarina Vukojevi Marta Balog Vedrana Ivi Milorad Zjali Marija Heffer Natalija Filipovi 《International journal of molecular sciences》2022,23(11)
The aim of this study was to determine the effects of altered ganglioside composition on the expression of Cx37, Cx40, Cx43, Cx45, and Panx1 in different kidney regions of St8sia1 gene knockout mice (St8sia1 KO) lacking the GD3 synthase enzyme. Experiments were performed in twelve male 6-month-old mice: four wild-type (C57BL/6-type, WT) and eight St8sia1 KO mice. After euthanasia, kidney tissue was harvested, embedded in paraffin wax, and processed for immunohistochemistry. The expression of connexins and Panx1 was determined in different regions of the kidney: cortex (CTX.), outer stripe of outer medulla (O.S.), inner stripe of outer medulla (IN.S.), and inner medulla (IN.MED.). We determined significantly lower expression of Cx37, Cx40, Cx45, and Panx1 in different parts of the kidneys of St8sia1 KO mice compared with WT. The most consistent decrease was found in the O.S. where all markers (Cx 37, 40, 45 and Panx1) were disrupted in St8si1 KO mice. In the CTX. region, we observed decrease in the expression of Cx37, Cx45, and Panx1, while reduced expression of Cx37 and Panx1 was more specific to IN.S. The results of the present study suggest that deficiency of GD3 synthase in St8sia1 KO mice leads to disruption of renal Cx expression, which is probably related to alteration of ganglioside composition. 相似文献
3.
Urban Novak Amalija Golobi
Natalija Klan
nik Vlasta Moha
ek-Groev Jernej Stare Joe Grdadolnik 《International journal of molecular sciences》2022,23(11)
Acetylenedicarboxylic acid dihydrate (ADAD) represents a complex with strong hydrogen bonding between the carboxylic OH and the water molecule. An X-ray re-examination of the ADAD crystal structure confirms the O…O distance of the short hydrogen bonds, and clearly shows different bond lengths between the two oxygen atoms with respect to the carbon atom in the carboxyl group, indicating a neutral structure for the complex. The neutral structure was also confirmed by vibrational spectroscopy, as no proton transfer was observed. The diffraction studies also revealed two polymorph modifications: room temperature (α) and low temperature (β), with a phase transition at approximately 4.9 °C. The calculated vibrational spectra are in satisfactory agreement with the experimental spectra. A comparison of the structure and the vibrational spectra between the ADAD and the oxalic acid dihydrate reveals some interesting details. The crystal structures of both crystal hydrates are almost identical; only the O…O distances of the strongest hydrogen bonds differ by 0.08 Å. Although it was expected that a larger O…O spacing in the ADAD crystal may significantly change the infrared and Raman spectra, especially for the frequency and the shape of the acidic OH stretching vibration, both the shape and frequency are almost identical, with all subpeaks topped on the broad OH stretching vibration. The O…O distance dependent are only in- and out-of-plane OH deformations modes. The presence of polarons due to the ionized defects was not observed in the vibrational spectra of ADAD. Therefore, the origin of the broad OH band shape was explained in a similar way to the acid dimers. The anharmonicity of a potential enhances the coupling of the OH stretching with the low-frequency hydrogen bond stretching, which, in addition to the Fermi resonance, structures the band shape of the OH stretching. The fine structure found as a superposition of a broad OH stretching is attributed to Davydov coupling. 相似文献
4.
Srećko Manasijević Natalija Dolić Zdenka Zovko Brodarac Mile Djurdjević Radomir Radiša 《Metallurgical and Materials Transactions A》2014,45(10):4580-4587
This paper presents the results of an analysis of the formation of an intermetallic bond between a ring carrier and an aluminum piston alloy. The ring carrier is made of austenitic cast iron (Ni-Resist) to increase the wear resistance of the first ring groove and is applied in highly loaded diesel engines. The most important thing is that the Ni-Resist (ferrous) must be bonded with a non-ferrous piston material during the casting of the piston. A metallographic investigation using an optical microscope in combination with the SEM/EDS analysis of the quality of the intermetallic bonding layer was done. The test results show that if the proper conditions are met, then the preparation of the ring carrier can be made successfully, as can the formation of the metal connection between the two materials of different qualities. 相似文献
5.
Natalija Subotinic 《Journal of Architectural Education》2013,67(1):35-44
AbstractArchitecture programs should include a curriculum on philosophy of architecture in the analytic philosophical tradition. I describe such a curriculum and distinguish it from both the typical architectural theory curriculum and the typical philosophical aesthetics courses. Without such a curriculum, students likely lack exposure to the philosophical approach to aesthetics that is dominant in American universities. 相似文献
6.
Natalija Dj Polovic Rada V Pjanovic Lidija M Burazer Sava J Velickovic Ratko M Jankov Tanja D Cirkovic Velickovic 《Journal of the science of food and agriculture》2009,89(1):8-14
BACKGROUND: It is thought that food sensitisers must be able to reach the intestine in order to sensitise patients. Pectin is a gel‐forming plant polysaccharide that can protect allergens from in vivo gastric digestion and in vitro pepsin digestion. The aim of this study was to examine if pectin gel formed in the acidic environment of the stomach can protect labile allergen from in vitro gastrointestinal digestion. RESULTS: Pectin forms a gel in the acidic conditions of gastric fluid up to a concentration of 1.0 ± 0.14 g L?1. Four allergenic fruits (kiwi, cherry, apple and banana) form gels in the same manner at the dilutions 14.8 ± 0.4; 8.4 ± 0.2, 9.4 ± 0.35 and 29.1 ± 0.2, respectively. The time necessary for dissolution of 50 g L?1 pectin gel in intestinal fluid was found to be 70 ± 0.2 min. Pectin gel formed in situ was able to protect Act c 1 from pepsin digestion for 1 h and from further intestinal digestion for one additional hour. CONCLUSION: Pectin gel in an acidic environment protects Act c 1 from pepsin digestion and dissolves slowly in the slightly basic environment of the intestine allowing the survival of fruit allergen for additional time and possible interaction with the gut immune system. Copyright © 2008 Society of Chemical Industry 相似文献
7.
Dragana Stanic Jelena Radosavljevic Natalija Polovic Milka Jadranin Milica Popovic Olga Vuckovic Lidija Burazer Ratko Jankov Tanja Cirkovic Velickovic 《International Dairy Journal》2009,19(12):746-752
The use of enzymes may improve the functional properties of various food ingredients. The aim of this study was to examine the effects of proteolytic contaminants in phenol oxidases on β-lactoglobulin (BLG). In the presence of Trametes versicolor laccase and Agaricus bisporus tyrosinase, both variants of BLG (A and B) underwent removal of a peptide from the N-terminus. The truncated forms were more susceptible to digestion by pepsin. The truncation of BLG resulted from contaminating proteases and not due to the action of phenol oxidases. The removal of N-terminal peptides proceeded quickly, while the rest of the globular protein remained resistant to proteolysis for up to 3 h. In the case of the application of enzymes in food bioprocessing, it may be important to carefully monitor the effects of contaminating proteases in enzyme preparations used. 相似文献
8.
9.
Deadlock detection in distributed database systems: a new algorithm and a comparative performance analysis 总被引:4,自引:0,他引:4
Natalija Krivokapić Alfons Kemper Ehud Gudes 《The VLDB Journal The International Journal on Very Large Data Bases》1999,8(2):79-100
This paper attempts a comprehensive study of deadlock detection in distributed database systems. First, the two predominant
deadlock models in these systems and the four different distributed deadlock detection approaches are discussed. Afterwards,
a new deadlock detection algorithm is presented. The algorithm is based on dynamically creating deadlock detection agents (DDAs), each being responsible for detecting deadlocks in one connected component of the global wait-for-graph (WFG). The
DDA scheme is a “self-tuning” system: after an initial warm-up phase, dedicated DDAs will be formed for “centers of locality”,
i.e., parts of the system where many conflicts occur. A dynamic shift in locality of the distributed system will be responded
to by automatically creating new DDAs while the obsolete ones terminate. In this paper, we also compare the most competitive
representative of each class of algorithms suitable for distributed database systems based on a simulation model, and point
out their relative strengths and weaknesses. The extensive experiments we carried out indicate that our newly proposed deadlock
detection algorithm outperforms the other algorithms in the vast majority of configurations and workloads and, in contrast
to all other algorithms, is very robust with respect to differing load and access profiles.
Received December 4, 1997 / Accepted February 2, 1999 相似文献
10.
Matea
uul Mirela Lozi Natalija Filipovi Samir anovi Ana Didovi Pavi
i Joko Petri
evi Nenad Kunac Violeta olji Mirna Saraga-Babi Suzana Konjevoda Katarina Vukojevic 《International journal of molecular sciences》2022,23(11)
The expression pattern of Connexins (Cx) 37, 40, 43, 45 and Pannexin 1 (Pnx1) was analyzed immunohistochemically, as well as semi-quantitatively and quantitatively in histological sections of developing 8th- to 12th-week human eyes and postnatal healthy eye, in retinoblastoma and different uveal melanomas. Expressions of both Cx37 and Cx43 increased during development but diminished in the postnatal period, being higher in the retina than in the choroid. Cx37 was highly expressed in the choroid of retinoblastoma, and Cx43 in epitheloid melanoma, while they were both increasingly expressed in mixoid melanoma. In contrast, mild retinal Cx40 expression during development increased to strong in postnatal period, while it was significantly higher in the choroid of mixoid melanoma. Cx45 showed significantly higher expression in the developing retina compared to other samples, while it became low postnatally and in all types of melanoma. Pnx1 was increasingly expressed in developing choroid but became lower in the postnatal eye. It was strongly expressed in epithelial and spindle melanoma, and particularly in retinoblastoma. Our results indicate importance of Cx37 and Cx40 expression in normal and pathological vascularization, and Cx43 expression in inflammatory response. Whereas Cx45 is involved in early stages of eye development, Pnx1might influence cell metabolism. Additionally, Cx43 might be a potential biomarker of tumor prognosis. 相似文献