488 research outputs found

    Effect of carboxymethyl cellulose-based coatings incorporated with Zataria multiflora Boiss. essential oil and grape seed extract on the shelf life of rainbow trout fillets

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    To prolong the shelf life of seafood products, lipid oxidation and growth of microorganisms should be retarded. The objective of the current study was evaluating the potential application of carboxymethyl cellulose (CMC) coatings incorporated with Zataria multiflora Boiss. essential oil (ZMEO) and grape seed extract (GSE) on chemical (thiobarbituric acid reactive substances (TBARS) and total volatile basic nitrogen (TVB-N)), microbial (total viable count, lactic acid bacteria and Pseudomonas spp.) and organoleptic attributes of rainbow trout fillets during refrigerated storage for twenty days. GCeMS analysis showed that ZMEO is rich in monoterpene phenols such as thymol and carvacrol. The following results were obtained after 20 days of storage: The minimum level of TVB-N was measured in the fillets coated with CMC + 2 v/v ZMEO + 0.5 v/v GSE. The minimum number of total viable bacteria, lactic acid bacteria and Pseudomonas spp. were determined in the fillets coated with CMC + 2 v/v ZMEO + 1 v/v GSE. The fillets coated with CMC + 1 v/v ZMEO + 1 v/v GSE showed the best organoleptic properties. Our results revealed that CMC-based coatings incorporated with ZMEO and GSE could improve chemical, microbial and sensorial characteristics of rainbow trout fillets during cold storage. © 2015 Elsevier Ltd

    Dependence of chaotic behavior on optical properties and electrostatic effects in double beam torsional Casimir actuation

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    We investigate the influence of Casimir and electrostatic torques on double beam torsional microelectromechanical systems with materials covering a broad range of conductivities of more than three orders of magnitude. For the frictionless autonomous systems, bifurcation and phase space analysis shows that there is a significant difference between stable and unstable operating regimes for equal and unequal applied voltages on both sides of the double torsional system giving rise to heteroclinic and homoclinic orbits, respectively. For equal applied voltages, only the position of a symmetric unstable saddle equilibrium point is dependent on the material optical properties and electrostatic effects, while in any other case there are stable and unstable equilibrium points are dependent on both factors. For the periodically driven system, a Melnikov function approach is used to show the presence of chaotic motion rendering predictions of whether stiction or stable actuation will take place over long times impossible. Chaotic behavior introduces significant risk for stiction, and it is more prominent to occur for the more conductive systems that experience stronger Casimir forces and torques. Indeed, when unequal voltages are applied, the sensitive dependence of chaotic motion on electrostatics is more pronounced for the highest conductivity systems.Comment: 24 pages, 11 figure

    Effect of Zataria multiflora Boiss Essential Oil and Grape Seed Extract on the Shelf Life of Raw Buffalo Patty and Fate of Inoculated Listeria monocytogenes

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    The present study was conducted to investigate the effect of Zataria multiflora Boiss essential oil (ZEO) and grape seed extract (GSE) on microbial and chemical changes in raw buffalo patty at a temperature of 8C. First, chemical composition and minimum inhibitory concentration of oil against Listeria monocytogenes were identified. Then, ZEO and GSE were added in raw buffalo patties and analyzed for spoilage microorganism count, lipid oxidation, pH, sensory attributes and inoculated L.monocytogenes survival at 8C for 9 days. Results revealed that samples containing 0.1 ZEO+0.2 GSE showed significant decrease in the growth of all tested microbial groups as well as the most decrease in the level of lipid oxidation at the end of storage period. Control and samples with 0.1 ZEO were the most preferred samples by sensory panelist, indicating that ZEO and GSE can be practically applied in food systems especially in meat in order to extend the shelf life. Practical Applications: Buffalo meat is highly prone to microbial and chemical spoilage as they are rich in essential nutrients and putrefying in nature. The adverse effects of various chemical preservatives caused to attract the consumer's attention to natural alternatives. Therefore, in order to increase the shelf life and quality characteristics of meat, new processing technologies and new ingredient systems that are associated with natural and organic foods are applied. These results demonstrate the potential combined use of grape seed extract and Zataria multiflora Boiss essential oil to the meat industry in the development of novel healthy meat products with improved shelf life and superior product quality. © 2015 Wiley Periodicals, Inc

    Antibacterial activity of acetic and lactic acid against Listeria monocytogenes and their effect on the intracellular constituent release

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    Background: Organic acids (e.g. acetic and lactic acid) have been used in foods as natural preservatives. Acetic acid and its salts are used in foods as antimicrobial and acidulant agents. The aim of this study was to evaluate the antibacterial activity of acetic and lactic acids against the Listeria monocytogenes. Materials and Methods: This experimental study was conducted at the Department of Food Hygiene (Faculty of Veterinary Medicine, Urmia University) during autumn 2015. The antibacterial effects of acetic and lactic acid against Listeria monocytogenes were determined using minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and cell constituents release methods. The concentration ranges of acetic and lactic acid (0.0195-10 and 0.043-22.2 μl/ml, respectively) were used to determine the MIC of acids. Results: Based on the results, acetic and lactic acid inhibited the growth of Listeria monocytogenes and acetic acid had stronger effect against the the bacterium. The MIC values for acetic acid and lactic acid were 2.5 and 5 μl/ml, respectively. Cell constituents release showed that acetic and lactic acids are able to lyze the bacterial cell. Conclusion: Acetic and lactic acids were effective in inhibiting the growth of Listeria monocytogenes and the antibacterial effect of acetic acid was stronger than that lactic acid. These acids can be used in foods in combination with other preservatives to inhibit the food borne pathogens and food spoilage microorganisms

    Comparing the effects of alcoholic extract of ginseng with itraconazole against Candida albicans and Candida krusei

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    Background: Candidiasis is a prevalent disease which is caused by different species of Candida. Herbal drugs (e.g. ginseng) were traditionally administrated for the treatment of different diseases. This study was carried out to compare the effect of alcoholic extract of ginseng with Itraconazole against Candida albicans (C. albicans) and Candida krusei (C. krusei). Material and Methods: This cross-sectional study was crried out on 22 and 8 species of C.albicans and 8 C.krusei, respectively which were isolated from vagina, urine and sputum of the patients. Using the CLSI M27 and disk diffusion methods the susceptibility test was done by Itraconazole (10 µg) and ginseng extract (1, 2, 4, 8, 16, 32, 64 and 128 mg.ml-1). The standard species of C. albicans (PTCC 5027) and C. Krusei (PTCC 5295) were used for the quality control purposes. Results: The lowest and highest minimum inhibitory concentration (MIC) for C. albicans and C. Kruzei was 0.0625 and 0.5 μg.ml-1, respectively for Itraconazole using the microdilution method. However, the lowest MIC and minimum fungal concentration (MFC) for alcoholic extract was 64 mg.ml-1 .The highest inhibition zone for C. albicans was 14 and 14-32 mm for alcoholic extract and Foritraconazole, respectively. Using the two methods no significant difference was seen between the alcoholic extract of ginseng (64 and 128 mg.ml-1) and the drug. (P<0.05) Conclusion: Considering the MICs and disk diffusion results, the ginseng extract (64,128 mg.ml-1) shows considerable antifungal effects compared to Itraconazole

    Immunomodulatory effects of human amniotic epithelial cells on naive CD4+ T cells from women with unexplained recurrent spontaneous abortion

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    Abstract Introduction Immune imbalance at the maternal-fetal interface plays a fundamental role in the pathogenesis of unexplained recurrent spontaneous abortion (URSA). Human amniotic epithelial cells (hAECs) possess pregnancy-friendly immunomodulatory effects. Here, we investigated how function of naive CD4+ T cells from URSA patients is affected by hAECs. Methods Phenotypic characteristics of hAECs were determined by flow cytometry and their effect on proliferation of allogeneic peripheral blood mononuclear cells (PBMCs) was evaluated by a BrdU cell proliferation assay. Naive CD4+ T cells were isolated from 25 URSA patients and 5 healthy women and co-cultured with hAECs. Immunomodulatory effects of hAECs on cytokines profile, proliferation of stimulated CD4+ T cells and induction of regulatory T cells (Tregs) were assessed by ELISA and flow cytometry, respectively. Functional competency of Tregs was evaluated in an allogeneic mixed lymphocyte reaction (MLR) system. Results hAECs did not elicit allogeneic proliferative responses of PBMCs, inhibited proliferation of naive CD4+ T cells, induced production of Th2 and suppressed production of Th1 and Th17 cytokines. hAECs showed the ability to induce differentiation of Tregs and production of transforming growth factor-beta1 (TGF-β1) and interleukin-10 (IL-10). This ability was found to be superior in control subjects compared to URSA patients. Indeed, Tregs generated in the presence of hAECs expressed higher levels of CTLA-4 compared to Tregs generated in their absence and restrained the proliferation of autologus PBMCs in MLR system. Conclusion Based on these findings, hAECs can be considered as one potential candidate in immunotherapy of patients with URSA. Keywords Immunomodulatory effects Amniotic epithelial cells Naive T cells Unexplained recurrent spontaneous abortio

    Adipose tissue-derived mesenchymal stem cells exert in vitro immunomodulatory and beta cell protective functions in streptozotocin-induced diabetic mice model

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    Regenerative and immunomodulatory properties of mesenchymal stem cells (MSCs) might be applied for type 1 diabetes mellitus (T1DM) treatment. Thus, we proposed in vitro assessment of adipose tissue-derived MSCs (AT-MSCs) immunomodulation on autoimmune response along with beta cell protection in streptozotocin- (STZ-) induced diabetic C57BL/6 mice model. MSCs were extracted from abdominal adipose tissue of normal mice and cultured to proliferate. Diabetic mice were prepared by administration of multiple low-doses of streptozotocin. Pancreatic islets were isolated from normal mice and splenocytes prepared from normal and diabetic mice. Proliferation, cytokine production, and insulin secretion assays were performed in coculture experiments. AT-MSCs inhibited splenocytes proliferative response to specific (islet lysate) and nonspecific (PHA) triggers in a dose-dependent manner (P < 0.05). Decreased production of proinflammatory cytokines, such as IFN-γ, IL-2, and IL-17, and increased secretion of regulatory cytokines such as TGF-β, IL-4, IL-10, and IL-13 by stimulated splenocytes were also shown in response to islet lysate or PHA stimulants (P < 0.05). Finally, we demonstrated that AT-MSCs could effectively sustain viability as well as insulin secretion potential of pancreatic islets in the presence of reactive splenocytes (P < 0.05). In conclusion, it seems that MSCs may provide a new horizon for T1DM cell therapy and islet transplantation in the future. © 2015 Hossein Rahavi et al

    Non-surgical removal of some stones from a red tailed catfish (Phractocephalus hemioliopterus) stomach as gastric foreign bodies

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    A red-tailed catfish (Phractocephalus hemioliopterus) referred to Aquatic Animal Health Department, Faculty of Veterinary Medicine, University of Tehran for showing lethargy, bottom sitting, extension of abdomen and severe abdominal injuries. Its abdomen was swollen and the bulk of the foreign bodies were easily palpated. The heaviness of foreign bodies had made swimming and buoyancy difficult for fish. Several radiographic images were taken after anaesthetizing the catfish with 10% carvacrol, 2 drops in 1 liter of water. Radiographs revealed some stones with their size, number and location. Stones were removed non-surgically through the large oral cavity using suitable forceps. Totally 16 stones and 2 shells were removed from the stomach of the fish. The catfish was then returned to the water where normal swimming and buoyancy was restored

    Development and evaluating multimarker models for guiding treatment decisions

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    Financial support for ProTWIN trial was provided by The Netherlands Organisation for Health Research and Development (ZonMw), the Hague, the Netherlands (grant number 200310004). Parvin Tajik is supported by an AXA Research Fund.Peer reviewedPublisher PD
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