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41.
42.
Fermentation of pomegranate juice by probiotic lactic acid bacteria   总被引:1,自引:0,他引:1  
In this research, production of probiotic pomegranate juice through its fermentation by four strains of lactic acid bacteria: Lactobacillus plantarum, L. delbruekii, L. paracasei, L. acidophilus was examined. Fermentation was carried out at 30°C for 72 h under microaerophilic conditions. Microbial population, pH, titrable acidity, sugar and organic acid metabolism were measured during the fermentation period and the viability of all strains was also determined during the storage time at 4°C within 4 weeks. The results indicated that L. plantarum and L. delbruekii increased the pH sharply at the initial stages of fermentation and the sugar consumption was also higher in comparison with other strains, better microbial growth was also observed for these two strains during fermentation. Citric acid, as a major organic acid in pomegranate juice was significantly consumed by all probiotic lactic acid bacteria. L. plantarum and L. delbruekii showed higher viability during the storage time. Viable cells remained at their maximum level within 2 weeks but decreased dramatically after 4 weeks. Pomegranate juice was proved to be a suitable media for production of a fermented probiotic drink.  相似文献   
43.
Antibody and T cell receptor genes are assembled from gene segments by V(D)J recombination to produce an almost infinitely diverse repertoire of antigen specificities. Recombination is initiated by cleavage of conserved recombination signal sequences (RSS) by RAG1 and RAG2 during lymphocyte development. Recent evidence demonstrates that recombination can occur at noncanonical RSS sites within Ig genes or at other loci, outside the context of normal lymphocyte receptor gene rearrangement. We have characterized the ability of the RAG proteins to bind and cleave a cryptic RSS (cRSS) located within an Ig V(H) gene segment. The RAG proteins bound with sequence specificity to either the consensus RSS or the cRSS. The RAG proteins nick the cRSS on both the top and bottom strands, thereby bypassing the formation of the DNA hairpin intermediate observed in RAG cleavage of canonical RSS substrates. We propose that the RAG proteins may utilize an alternative mechanism for double-stranded DNA cleavage, depending on the substrate sequence. These results have implications for further diversification of the antigen receptor repertoire as well as the role of the RAG proteins in genomic instability.  相似文献   
44.
Adiponectin which possesses anti-inflammatory and insulin-sensitizing properties is elevated in blood circulation of liver cirrhosis patients. The genetic variations in the adiponectin gene can affect the circulating adiponectin level and stimulation of adiponectin receptor that may affect the activity of adiponectin. We investigated the effect of adiponectin single nucleotide polymorphisms (SNP) 45 T/G and adiponectin receptor-2 gene SNP 795G/A in cirrhotic Iranian population. A total of 97 cirrhotic patients and 128 healthy controls from Iranian population were genotyped for the adiponectin and adiponectin receptor 2 gene (+45T>G and 795G/A) by polymerase chain reaction-restriction fragment length polymorphism. G frequency was 21.1% versus 12.89% (P = 0.001) for SNP45, and G frequency was 75.8% versus 76.2% (P = 0.526) for SNP795G/A in the patients and control group, respectively. Based on our findings, the expression of the G allele at SNP45 is higher in the patient group compared with healthy subjects, suggesting that it may affect liver injury through changes in the plasma adiponectin level.  相似文献   
45.
Most of the modulating effects of cannabinoids on pain are through putative cannabinoid CB1 and CB2 receptors. However, the involvement of other receptors is also suggested. Cannabinoid compounds with analgesic activity such as palmitoylethanolamide (PEA) show low affinity to CB1 and CB2 receptors, yet selectively activate GPR55 receptors. The objective of the present study was to evaluate the possible role of spinal CB1 and GPR55 receptors on antinociceptive activity of PEA in formalin test as well as in the spinal expression of IL1-β in rat. Intrathecal (i.t.) administration of PEA (1, 10 μg) significantly decreased both pain-related scores in formalin test and IL1-β expression in rat spinal cord. Pretreatment of rats with low doses of CB1 receptor antagonist/GPR55 receptor agonist AM251 (10, 100 ng; i.t.), did not attenuated the effect of PEA, yet even significantly increased the effect of PEA on IL1-β expression in rat spinal cord. Interestingly, i.t. administration of low doses of AM251 per se significantly decreased both pain related behavior and spinal IL1-β expression in formalin test. These findings suggest the possible involvement of receptors other than CB1 receptors in spinal pain pathways, such as GPR55, in pain modulating activity of cannabinoids.  相似文献   
46.
Airway remodelling in asthma involves various mediators modulating the production/breakdown of collagen by lung fibroblasts. Matrix metalloproteinase-1 (MMP-1) plays an important role in collagen breakdown. We recently showed that epithelial cell-derived extracellular form of 14-3-3σ is an important inducer of MMP-1 expression in skin fibroblasts. Thus, we hypothesized that 14-3-3 proteins are important regulators of MMP-1 expression in the respiratory airway. We examined the presence of extracellular 14-3-3 proteins in conditioned media obtained from primary lung epithelial cells, A549 and HS24 cells, and their effect on MMP-1 expression by lung fibroblasts (IMR-90). In addition, we evaluated IMR-90 response to 14-3-3 proteins in the presence of transforming growth factor-β(1) (TGF-β(1)), a cytokine known to decrease MMP-1 expression by fibroblasts. Extracellular 14-3-3α/β, but not -σ, is released by the human-derived lung epithelial cell lines, A549 and HS24. Unlike dermal fibroblasts, IMR-90 cells do not produce MMP-1 in response to 14-3-3σ. Conversely, MMP-1 production was induced following treatment of IMR-90 with recombinant or lung epithelial cell-derived 14-3-3α/β. These findings were also confirmed using primary human bronchial epithelial cells and lung fibroblasts obtained from non-asthmatic patients. The MMP-1-inducing effect of 14-3-3α/β on IMR-90 was not inhibited by TGF-β(1). Lung epithelial cell-derived 14-3-3α/β has a potent MMP-1-inducing effect on airway fibroblasts. Modulation of MMP-1 by 14-3-3α/β, may be important in the alteration of collagenase production associated with airway remodelling in obstructive lung diseases. Our data indicate that 14-3-3 proteins may be potential targets for future therapeutic strategies aimed at modulating tissue remodelling in asthma.  相似文献   
47.
A free-ranging, adult, male Persian leopard (Panthera pardus ciscaucasica) was found at Geloul-Sarani protected zone, province of North-Khorasan, Iran and transported to the Ferdowsi University of Mashhad Veterinary Teaching Hospital. The leopard had normal temperature and respiratory and cardiac frequency, but was significantly dehydrated and had elevated capillary perfusion. The animal also was cachectic, with pale mucus membranes, third-eyelid protrusion, and bilaterally enlarged submandibular lymph nodes. The leopard was stabilized by intensive fluid and electrolyte therapy and hospitalized. In 2 days, the leopard had improved clinically but had severe ataxia and head pressing. Blood smears revealed gamonts of Hepatozoon sp. within some neutrophils. Hematologic and plasma chemistry abnormalities included moderate anemia, leukocytosis, hypocholestrolemia, and hypophosphatemia. In radiographic evaluations, no sign of periosteal reactions or new bone formation was seen on the skull, spine, long bones, pelvis, or vertebrae. The leopard was treated successfully with Tazocin and clindamycin for 1 mo. This is the first detection of a Hepatozoon sp. in wild Felidae in Iran. Because most Iranian wild felids and canids are endangered, knowing whether Hepatozoon infection represents a threat for these animals is important.  相似文献   
48.
The susceptibility of lipids to oxidation is one of the most fundamental problems in oil-in-water emulsions. A response surface methodology 5-level-3-factor central-composite rotatable design was applied to study the effects of key formula ingredients including walnut oil (WO, 3-6%, w/w), gum arabic (GA, 5-10%, w/w) and xanthan gum (XG, 0.05-0.15%, w/w) on lipid oxidation in walnut-beverage emulsions. During 30 days’ storage, the oxidation process was monitored by evaluating the peroxide value, anisidine value and total oxidation (Totox) value in different emulsion formulations. Use of XG as a stabilizer at high concentrations considerably inhibited the oxidation of WO in the prepared emulsions. The experimental data were satisfactorily fitted to quadratic models using multiple regression analysis. The optimum conditions to obtain the minimum peroxide (0.923 mequiv. O2/kg oil), anisidine (0.500) and Totox (2.347) values are met when a walnut-beverage emulsion is formulated with 3% WO, 10% GA and 0.12% XG.  相似文献   
49.
BACKGROUND: Angiolymphoid hyperplasia with eosinophilia (ALHE) is an uncommon vascular inflammatory lesion usually involving the dermis or subcutaneous tissue of the head-neck region of middle-aged women. Histologically, this lesion shows a florid proliferation of vessels lined by particular endothelial cells and an inflammatory infiltrate composed of lymphocytes and eosinophils. CASE: A 30-year-old woman presented with multiple periauricular skin nodules. Fine needle aspiration cytology shows a mixed population of lymphoid cells with an admixture of eosinophils and large cells with vesicular nuclei and prominent nucleoli. A diagnosis of AHLE was confirmed on histopathologic examination. CONCLUSION: Various conditions, both benign and malignant, may mimic Kimura's disease clinically and on smears. These must be ruled out before making a diagnosis of Kimura's disease. The cytologic features of Kimura's disease have to be interpreted in the appropriate clinical setting in order to make a correct preoperative diagnosis.  相似文献   
50.
Bioprocess and Biosystems Engineering - Cultivation of microalgae in wastewater is a promising and cost-effective approach for both CO2 biofixation and wastewater remediation. In this study, a new...  相似文献   
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