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1.
The ultrastructural diagnosis of tumors requires a careful analysis that should be done in an orderly fashion. It requires precise planning from the time of specimen collection to the selection of the area to be examined. Pictures must be taken systematically and every micrograph should allow to answer whether the number of cells photographed is adequate; whether mitoses are present, what is the pattern of the tumor; what is the appearance of the cell membrane; whether the cells are joined by junctional complexes; whether free surfaces possess microvilli or cilia; what organelles are present and how they are distributed; whether there are secretory granules, melanosomes, or other cytoplasmic elements. Nuclear and nucleolar size and shape have to be taken into consideration. The composition of the interstitial extracellular matrix is important in certain types of tumors. Although these questions are not the only ones to be addressed, their use in a logical fashion is helpful when it concerns the ultrastructural diagnosis. 相似文献
2.
The effect of oral administration, for 24 or 48 hr, of different octadeca fatty acids containing a 9,12-dienoic structure
on the fatty acid composition and Δ9 desaturation activity of liver microsomes of rat fed a fat-free diet was studied. The
ethyl esters of linoelaidic and γ-linolenic acids, the methyl ester of linoleic acid and free columbinic acid were administered
to rats maintained on a fat-free diet. The supplementation of the fat-free diet with linoelaidate produced no relevant changes
in the fatty acid composition pattern of liver microsomes and did not modify the percentage of conversion of palmitic to palmitoleic
acid. The addition of linoleate or γ-linolenate to the fat-free diet returned liver microsome Δ9 desaturation activity toward
the control and partially restored the liver microsome fatty acid spectrum found in the fat-free diet. Columbinic acid (5-trans-9-cis,12-cis-18∶3), which cannot be transformed into arachidonic acid, also decreased the Δ9 desaturation activity enhanced by the fat-free
diet and evoked changes in the microsomal fatty acid composition similar to those produced by the ω6 fatty acids. These results
suggest that the modulation of Δ9 desaturase activity evoked by dietary administration of unsaturated acids of ω6 series would
depend on thecis double bond configuration of these acids. 相似文献
3.
Marja Riekkola-Vanhanen Ph.Lic. Seppo Heimala D.Sc. Carita A. Sivelä M.Sc. Felipe Viguera M.Sc. Irma Varjola M.Sc. Seppo I. Niemelä Ph.D. Olli H. Tuovinen Ph.D. 《JOM Journal of the Minerals, Metals and Materials Society》1993,45(12):51-53
The oxidation of an auriferous pyrite ore sample was evaluated in biological leaching experiments for subsequent gold recovery via cyanidation. In batch cultures, organisms derived from the mine site oxidized pyrite and ferrous iron at pH values as low as pH 0.6. The recovery of gold was variable in shake flask experiments. In stirred tank bioreactor leaching, gold recovery was proportional to the extent of iron dissolution by bioleaching. The leaching of arsenic from the sample was also directly proportional to iron dissolution. 相似文献
4.
Alessia DAloia Federica Arrigoni Renata Tisi Alessandro Palmioli Michela Ceriani Valentina Artusa Cristina Airoldi Giuseppe Zampella Barbara Costa Laura Cipolla 《International journal of molecular sciences》2020,21(23)
Palmitoylethanolamide (PEA) belongs to the class of N-acylethanolamine and is an endogenous lipid potentially useful in a wide range of therapeutic areas; products containing PEA are licensed for use in humans as a nutraceutical, a food supplement, or food for medical purposes for its analgesic and anti-inflammatory properties demonstrating efficacy and tolerability. However, the exogenously administered PEA is rapidly inactivated; in this process, fatty acid amide hydrolase (FAAH) plays a key role both in hepatic metabolism and in intracellular degradation. So, the aim of the present study was the design and synthesis of PEA analogues that are more resistant to FAAH-mediated hydrolysis. A small library of PEA analogues was designed and tested by molecular docking and density functional theory calculations to find the more stable analogue. The computational investigation identified RePEA as the best candidate in terms of both synthetic accessibility and metabolic stability to FAAH-mediated hydrolysis. The selected compound was synthesized and assayed ex vivo to monitor FAAH-mediated hydrolysis and to confirm its anti-inflammatory properties. 1H-NMR spectroscopy performed on membrane samples containing FAAH in integral membrane protein demonstrated that RePEA is not processed by FAAH, in contrast with PEA. Moreover, RePEA retains PEA’s ability to inhibit LPS-induced cytokine release in both murine N9 microglial cells and human PMA-THP-1 cells. 相似文献
5.
6.
Physicochemical Properties,Fatty Acid Profiles,and Sensory Characteristics of Fermented Beef Sausage by Probiotics Lactobacillus plantarum IIA‐2C12 or Lactobacillus acidophilus IIA‐2B4 下载免费PDF全文
Irma Isnafia Arief Dyah Nurul Afiyah Zakiah Wulandari Cahyo Budiman 《Journal of food science》2016,81(11):M2761-M2769
Probiotics may be used to enhance the functionality and nutritional values of fermented sausages. This study aims to evaluate the physicochemical and sensory properties of beef sausages fermented by lactic acid bacteria of Lactobacillus plantarum IIA‐2C12 and L. acidophilus IIA‐2B4. These strains were isolated from beef cattle and have shown to display probiotic features. While the nutrient contents were not affected by the probiotics, the pH, texture, and color varied among the sausages. Further analysis on fatty acids showed different profiles of saturated (C14:0, C17:0, and C20:0) and unsaturated (C14:1, C18:1n9c, C18:2n6c, and C22:6n3) fatty acids in sausages with probiotics. Gas chromatography–mass spectrometry further revealed some flavor development compounds including acid, alcohols, aldehydes, aromatic, ketones, sulfur, hydrocarbons and terpenes, varied among the sausages. Hedonic test showed no difference in the preference toward aroma, texture, and color for untrained panelists. 相似文献
7.
Satoru Shindo Irma Josefina Savitri Takenobu Ishii Atsushi Ikeda Roodelyne Pierrelus Alireza Heidari Keisuke Okubo Shin Nakamura Umadevi Kandalam Mohamad Rawas-Qalaji Elizabeth Leon Maria Rita Pastore Patrick Hardigan Toshihisa Kawai 《International journal of molecular sciences》2022,23(6)
Effects of the antiosteoblastogenesis factor Semaphorin 4D (Sema4D), expressed by thrombin-activated platelets (TPs), on osteoblastogenesis, as well as osteoclastogenesis, were investigated in vitro. Intact platelets released both Sema4D and IGF-1. However, in response to stimulation with thrombin, platelets upregulated the release of Sema4D, but not IGF-1. Anti-Sema4D-neutralizing monoclonal antibody (mAb) upregulated TP-mediated osteoblastogenesis in MC3T3-E1 osteoblast precursors. MC3T3-E1 cells exposed to TPs induced phosphorylation of Akt and ERK further upregulated by the addition of anti-sema4D-mAb, suggesting the suppressive effects of TP-expressing Sema4D on osteoblastogenesis. On the other hand, TPs promoted RANKL-mediated osteoclastogenesis in the primary culture of bone-marrow-derived mononuclear cells (BMMCs). Among the known three receptors of Sema4D, including Plexin B1, Plexin B2 and CD72, little Plexin B2 was detected, and no Plexin B1 was detected, but a high level of CD72 mRNA was detected in RANKL-stimulated BMMCs by qPCR. Both anti-Sema4D-mAb and anti-CD72-mAb suppressed RANKL-induced osteoclast formation and bone resorptive activity, suggesting that Sema4D released by TPs promotes osteoclastogenesis via ligation to a CD72 receptor. This study demonstrated that Sema4D released by TPs suppresses osteogenic activity and promotes osteoclastogenesis, suggesting the novel property of platelets in bone-remodeling processes. 相似文献
8.
Results of a study on the modifying mechanical properties of loose optical‐fiber poly(butylene terephthalate) (PBT) tubes, produced during the standard industrial extrusion process, show that heat treatment make the structure of their material to change. The study comprised measurements of mechanical strengths properties of the tubes (tensile strength, compression strength, kinking) and determination of tube material structure [by differential thermal analysis (DTA), wide angle X‐ray scattering analysis (WAXD), and scanning electron microscopy (SEM)]. Results of the study allowed observation that the annealing at 70°C for 34 h of the tubes caused the crystalline α phase to increase in the tube material from ~28.5% to ~31.5% and the structure of the existing crystallites to become more perfect. This made the values of certain mechanical properties of the tubes to increase even by as much as 30%. The tubes following such thermal treatment could be used in cables exposed to heavy‐duty operation in arduous environments, where a larger margin from the standpoint of mechanical properties is required. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2130–2134, 2002 相似文献
9.
Natural Palm Olein Polyol as a Replacement for Polyether Polyols in Viscoelastic Polyurethane Foam 下载免费PDF全文
H. Nurul ‘Ain T. I. Tuan Noor Maznee M. N. Norhayati M. A. Mohd Noor S. Adnan P. P. Kosheela Devi S. Mohd Norhisham S. K. Yeong A. H. Hazimah Irma Campara Vahid Sendijarevic Ibrahim Sendijarevic 《Journal of the American Oil Chemists' Society》2016,93(7):983-993
The impact of replacing three polyether polyols with different levels of a single palm olein‐based natural oil polyol (NOP) was systematically correlated with the changes in foaming reactivity, cell structure, physico‐mechanical properties, and morphology of viscoelastic (VE) foams. The data show that replacing the polyether polyols with the NOP slightly increased the rate of the foaming reactivity. Increasing the NOP content resulted in increased cell size and cells remained fully open. Increased NOP content contributed to higher load bearing properties of VE foam, which can be attributed to higher functionality of NOP compared to polyether polyols. Addition of the NOP slightly increased the resilience of the foams, however, the hysteresis which is the measure of energy absorption remained mostly unaffected. Age properties, characterized by dry and humid compression sets, were mostly unaffected by the replacement of the polyether polyol with the NOP. The addition of NOP did not impact the morphology of the VE foam polymer matrix, which appears to retain a low degree of hard and soft segment domain separation. Overall, the results demonstrate a feasibility that the NOP can be used to partially replace the polyether polyols in VE polyurethane foams without significant impact on the functional performance. 相似文献
10.
Gaia Pucci Giusi Irma Forte Vincenzo Cavalieri 《International journal of molecular sciences》2021,22(16)
Radiotherapy is still a long way from personalizing cancer treatment plans, and its effectiveness depends on the radiosensitivity of tumor cells. Indeed, therapies that are efficient and successful for some patients may be relatively ineffective for others. Based on this, radiobiological research is focusing on the ability of some reagents to make cancer cells more responsive to ionizing radiation, as well as to protect the surrounding healthy tissues from possible side effects. In this scenario, zebrafish emerged as an effective model system to test for radiation modifiers that can potentially be used for radiotherapeutic purposes in humans. The adoption of this experimental organism is fully justified and supported by the high similarity between fish and humans in both their genome sequences and the effects provoked in them by ionizing radiation. This review aims to provide the literature state of the art of zebrafish in vivo model for radiobiological studies, particularly focusing on the epigenetic and radiomodifying effects produced during fish embryos’ and larvae’s exposure to radiotherapy treatments. 相似文献