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51.
52.
The orexinergic system in rainbow trout Oncorhynchus mykiss and its regulation by dietary lipids 下载免费PDF全文
Ettore Varricchio Finizia Russo Elena Coccia Giovanni Mario Turchini David Scott Francis Marina Paolucci 《Microscopy research and technique》2015,78(8):707-714
In this study, we report the distribution of orexin A (OXA), orexin B (OXB), and orexin receptor (OX2R) immunoreactive (ir) cells in the hypothalamus and gastrointestinal tract of Oncorhynchus mykiss fed diets with different dietary fatty acid compositions. Trout were fed five iso‐energetic experimental diets containing fish oil, or one of four different vegetable oils (olive, sunflower, linseed, and palm oils) as the added dietary lipid source for 12 weeks. OXA, OXB, and OX2R immunoreactive neurons and nervous fibers were identified in the lateral and ventro‐medial hypothalamus. OXA, OXB, and OX2R ir cells were found in the mucosa and glands of the stomach and in the mucosa of both the pyloric cecae and intestine. OX2R ir cells were localized in the mucosa layer of both the pyloric cecae and intestine. These immunohistochemical (IHC) results were confirmed via Western blotting. Antibodies against preproorexin (PPO) crossreacted with a band of ~16 kDa in the hypothalamus, stomach, pyloric cecae, and intestine. Antibodies against OX2R crossreacted with a band of ~38 kDa in the hypothalamus, pyloric cecae, and intestine. The presence and distribution of OXA, OXB, and OX2R ir cells in the hypothalamus and gastrointestinal tract did not appear to be affected by dietary oils. The presence of orexin system immunoreactive cells in the stomach, pyloric cecae, and intestine of rainbow trout, but not in the enteric nervous system, could suggest a possible role of these peptides as signaling of gastric emptying or endocrine modulation, implying a main local action played by orexins. Microsc. Res. Tech. 78:707–714, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
53.
Ana Julia Dal Forno Fernando Augusto Pereira Fernando Antonio Forcellini Liane M. Kipper 《The International Journal of Advanced Manufacturing Technology》2014,72(5-8):779-790
Value stream mapping (VSM) is an important tool of the lean approach and is used to identify value-adding activities and those considered wasteful of materials and the flow of information and people. However, when not applied correctly, VSM can complicate the identification of waste, lead to misinterpretations and assessment mistakes, and undermine the implementation of future improvements. The purpose of this paper is to investigate the main difficulties and limitations encountered during the construction of current state maps, analysis of the associated causes, and pointing out of guidelines to facilitate the use of VSM to map processes. To do so, a search and evaluation of papers in journals, conferences, theses, and dissertations was conducted, and the articles were categorized according to the field of application (factory floor, supply chain, product development and services) and approach (theoretical or practical). In conclusion, this paper criticizes some ways that VSM has been used, observing that important constraints created by its application must be considered and that when used incorrectly, the tool can lead to mistakes that can cause problems instead of benefits. Considering the problems identified, the paper suggests future works for improving the use of VSM for mapping processes. 相似文献
54.
Effects of maturation and aging on the pressure‐bearing region of the plantaris longus tendon of the bullfrog (Lithobates catesbeianus) 下载免费PDF全文
Valdenilson José Zorel Jymenez De Morais Andrea Aparecida de Aro Laurecir Gomes Marcelo Augusto Marretto Esquisatto 《Microscopy research and technique》2014,77(10):797-805
The plantaris longus tendon (PLT) in bullfrog develops a fibrocartilage‐like tissue in the area that is functionally subject to compressive forces. The aim of this study was to analyze the modifications of the pressure‐bearing region in bullfrog PLT with different ages (7, 180, and 1,080 days after the end of metamorphosis) using histomorphometric, ultrastructural and biochemical methods. Weak basophilia and cells with a fibroblastic phenotype were observed in the compression region at 7 days of age. On the other hand, a large area of intense tissue basophilia associated with a chondroblast‐like cell population was noted at the other ages. Collagen fibers exhibited a three‐dimensional network‐like arrangement at all ages. The number of connective tissue cells increased between 7 and 180 days of age and was reduced in older animals. The 180‐day‐old animals presented a well‐developed pericellular matrix rich in proteoglycans. The mean diameter of collagen fibrils increased from 7 to 180 days and was the same at 1,080 days. Glycosaminoglycan content was higher in 7‐day‐old animals. A higher amount of hydroxyproline was observed at 180 and 1,080 days. The swelling test showed a significant increase of wet weight in 7‐day‐old animals. In conclusion, the alterations that occur in the pressure‐bearing of bullfrog PLT are the result of physiological alterations of the animal with the maturation and aging. Microsc. Res. Tech. 77:797–805, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
55.
Effect of Aloe vera application on the content and molecular arrangement of glycosaminoglycans during calcaneal tendon healing 下载免费PDF全文
Andrea Aparecida De Aro Marcelo Augusto Marretto Esquisatto Umar Nishan Mylena Oliveira Perez Rodney Alexandre Ferreira Rodrigues Mary Ann Foglio João Ernesto De Carvalho Laurecir Gomes Benedicto De Campos Vidal Edson Rosa Pimentel 《Microscopy research and technique》2014,77(12):964-973
Although several treatments for tendon lesions have been proposed, successful tendon repair remains a great challenge for orthopedics, especially considering the high incidence of re‐rupture of injured tendons. Our aim was to evaluate the pharmacological potential of Aloe vera on the content and arrangement of glycosaminoglycans (GAGs) during tendon healing, which was based on the effectiveness of A. vera on collagen organization previously observed by our group. In rats, a partial calcaneal tendon transection was performed with subsequent topical A. vera application at the injury site. The tendons were treated with A. vera ointment for 7 days and excised on the 7th, 14th, or 21st day post‐surgery. Control rats received ointment without A. vera. A higher content of GAGs and a lower amount of dermatan sulfate were detected in the A. vera‐treated group on the 14th day compared with the control. Also at 14 days post‐surgery, a lower dichroic ratio in toluidine blue stained sections was observed in A. vera‐treated tendons compared with the control. No differences were observed in the chondroitin‐6‐sulfate and TGF‐β1 levels between the groups, and higher amount of non‐collagenous proteins was detected in the A. vera‐treated group on the 21st day, compared with the control group. No differences were observed in the number of fibroblasts, inflammatory cells and blood vessels between the groups. The application of A. vera during tendon healing modified the arrangement of GAGs and increased the content of GAGs and non‐collagenous proteins. Microsc. Res. Tech. 77:964–973, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
56.
Maria Mastrodonato Donatella Mentino Angela Lopedota Annalisa Cutrignelli Giovanni Scillitani 《Microscopy research and technique》2017,80(2):239-249
Intracellular glycans in the urothelium of urinary bladder of 10 adult male Landrace pigs were characterized in situ by immunohistochemical detection of Muc1 mucin by anti MUC1 from rabbit, conventional histochemical techniques (Periodic‐Acid Schiff, Alcian Blue pH 2.5, High‐Iron Diamine), and binding with 13 lectins (PNA, DBA, RCA‐I, WGA, SBA, BSI‐B4, ConA, AAA, UEA‐I, LTA, LFA, MAA‐II, SNA) combined with chemical and enzymatic pre‐treatments (β‐elimination, desulfation and neuraminidase) to gather reference data for this model animal. Muc1 mucin was detected in the secreting granules of superficial cells and the underlying layer of intermediate cells. The secreting granules in both intermediate cells and superficial cells were rich in carbohydrates, with the oligosaccharidic chains mostly O‐linked to proteins. Glycoproteins were prevailing over glycosaminoglycans (GAGs). In both superficial and intermediate cells sulfated and/or sialylated glycans were present, sulfation decreasing in the deeper layers. Lectin‐binding detected presence of terminal sialic acid linked mostly in α2,6 to GalNAc, Gal terminal or subterminal to sulfates, GalNAc, GlcNAc, and Fuc, mostly linked in α1,6, α1,3 α1,4 and α1,2 to GlcNAc or Gal, but not to lactosamine chains. Except for fucosylation, the oligosaccharidic chains in the glycoproteins of the urothelium of pig urinary bladder were similar to those linked to human MUC1, which is fundamental in cell adhesion and immunological processes in the urothelium. The co‐distribution of Muc1 and saccharidic residues suggests that many of them are linked to the glycoprotein. 相似文献
57.
Pennelli G 《The Review of scientific instruments》2008,79(3):033902
High resolution electron and ion beam lithographies, fundamental tools for nanofabrication and nanotechnologies, require fast and high precision (high bit number) pattern generators. In the present work a solution for increasing the bit number, and preserving the speed of the system, is presented. A prototype with effective 18 bit resolution and with a write speed as fast as 10 MHz has been successfully tested: details of the adopted hardware solution are presented and described. This solution is very general and can be used in all those applications that require the generation of control voltages with an high bit number (high precision) at high speed, such as, for example, the scanning probe microscopy and nanomanipulation. Software solutions for increasing the data transfer efficiency are also presented; the aim of the adopted solutions is to preserve the flexibility and adaptability of the pattern generator to different writing strategies. 相似文献
58.
Anita Giglio Pietro Brandmayr Renato Dalpozzo Giovanni Sindona Antonio Tagarelli Federica Talarico Tullia Zetto Brandmayr Enrico A. Ferrero 《Microscopy research and technique》2009,72(5):351-361
This study documents the defensive function of flavored humor secreted by the abdominal glands of Carabus lefebvrei pupae. The morphology and the ultrastructure of these glands were described and the volatile compounds of glands secretion were identified by gas chromatography/mass spectrometry. The ultrastructure analysis shows an acinose complex formed by about 50 clusters. Each cluster has 20 glandular units and the unit—composed of one secretory and one canal cell lying along a duct—belongs to the class 3 cell type of Quennedey (1998). In the cytoplasm, the secretory cell contains abundant rough endoplasmatic reticula, glycogen granules, numerous mitochondria, and many well-developed Golgi complexes producing electron-dense secretory granules. Mitochondria are large, elongated, and often adjoining electronlucent vesicles. The kind and the origin of secretory granules varying in size and density were discussed. The chemical analysis of the gland secretion revealed the presence of a mixture of low molecular weight terpenes, ketones, aldehydes, alcohols, esters, and carboxylic acids. Monoterpenes, especially linalool, were the major products. We supposed that ketones, aldehydes, alcohols, esters, and carboxylic acids have a deterrent function against the predators and monoterpenes provide a prophylaxis function against pathogens. Microsc. Res. Tech., 2009. © 2008 Wiley-Liss, Inc. 相似文献
59.
Augusto Lanzón Tomás Albi Arturo Cert Jaime Gracián 《Journal of the American Oil Chemists' Society》1994,71(3):285-291
In numerous Spanish virgin olive oils, 6,10-dimethyl-1-undecene, various sesquiterpenes, the series ofn-alkanes from C14 to C35, n-8-heptadecene and squalene are the only less volatile components detected by gas chromatography
in the hydrocarbon fraction. In oils from olives of the Arbequine variety, a series ofn-9-alkenes has also been found. In refined oils, notable features are the absence of the most volatile compounds and the appearance
of other hydrocarbons produced during the refining process. Among these,n-alkanes, alkadienes (mainlyn-hexacosadiene), stigmasta-3,5-diene, isomerization products of squalene, isoprenoidal polyolefins coming from hydroxy derivatives
of squalene and steroidal hydrocarbons derived from 24-methylene cycloartanol were identified. Physical refining produces
larger amounts of degradation products and greater losses ofn-alkanes than chemical processing. Squalene is the major hydrocarbon component in all oils, both virgin and refined. The ranges
of concentration for the different hydrocarbons found in Spanish virgin olive oils are presented. 相似文献
60.
L. A. Gioielli R. N. M. Pitombo M. Vitolo R. Baruffaldi M. N. Oliveira M. S. Augusto 《Journal of the American Oil Chemists' Society》1994,71(6):579-582
The lipase-catalyzed interesterification of oils and fats gives products that are unobtainable by chemical interesterification
methods. Acidolysis of babassu fat and palmitic acid, catalyzed by immobilized lipase (Lipozyme; Novo Industri, Bagsveard,
Denmark), was studied. The reactions were performed at 65°C with 5% w/w enzyme for 4 h. The molar proportions of babassu fat/palmitic
acid were 1∶0.1, 1∶0.3 and 1∶0.5. At the end of the reaction period, the catalyst particles were removed by filtration, and
the residual oil was extracted with organic solvent (diethyl ether). The recovered particles were then reused. The palmitic
acid content of babassu fat before and after acidolysis changed from 10 to 22% at a molar proportion of 1∶0.5. The equilibrium
was attained in about 4 h. The original water and enzymatic activities of Lipozyme were maintained after acidolysis. Water
sorption isotherms of the immobilized enzyme were determined at 25, 35 and 45°C. From the temperature dependence of the isotherms,
isosteric heats of sorption were evaluated by means of the Clausius Clapeyron equation. Monolayer moisture content was calculated
by means of the B.E.T. and Guggenhein-Anderson-De Boer analyses.
Paper presented at the International Meeting on Fats and Oils Technology, Universidade Estadual de Campinas, Brazil, 1991. 相似文献