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991.
Systemic lupus erythematosus (SLE) is known as an autoimmune disorder that is characterized by the breakdown of self-tolerance, resulting in disease onset and progression. Macrophages have been implicated as a factor in the development of SLE through faulty phagocytosis of dead cells or an imbalanced M1/M2 ratio. The study aimed to investigate the immunomodulatory effects of Lactobacillus delbrueckii and Lactobacillus rhamnosus on M1 and M2 macrophages in new case lupus patients. For this purpose, blood monocytes were collected from lupus patients and healthy people and were cultured for 5 days to produce macrophages. For 48 h, the macrophages were then cocultured with either probiotics or lipopolysaccharides (LPS). Flow cytometry and real-time polymerase chain reaction were then used to analyze the expression of cluster of differentiation (CD) 14, CD80, and human leukocyte antigen – DR (HLADR) markers, as well as cytokine expression (interleukin [IL]1-β, IL-12, tumor necrosis factor α [TNF-α], IL-10, and transforming growth factor beta [TGF-β]). The results indicated three distinct macrophage populations, M0, M1, and M2. In both control and patient-derived macrophage-derived monocytes (MDMs), the probiotic groups showed a decrease in CD14, CD80, and HLADR expression compared to the LPS group. This decrease was particularly evident in M0 and M2 macrophages from lupus patients and M1 macrophages from healthy subjects. In addition, the probiotic groups showed increased levels of IL-10 and TGF-β and decreased levels of IL-12, IL1-β, and TNF-α in MDMs from both healthy and lupus subjects compared to the LPS groups. Although there was a higher expression of pro-inflammatory cytokines in lupus patients, there was a higher expression of anti-inflammatory cytokines in healthy subjects. In general, L. delbrueckii and L. rhamnosus could induce anti-inflammatory effects on MDMs from both healthy and lupus subjects.  相似文献   
992.
Polyethylene oxide has been researched extensively as an alternative polymer to hydroxypropyl methylcellulose (HPMC) in controlled drug delivery due to its desirable swelling properties and its availability in a number of different viscosity grades. Previous studies on HPMC have pointed out the importance of particle size on drug release, but as of yet, no studies have investigated the effect of particle size of polyethylene oxide (polyox) on drug release. The present study explored the relationship between polymer level and particle size to sustain the drug release. Tablets produced contained theophylline as their active ingredient and consisted of different polyethylene oxide particle size fractions (20–45, 45–90, 90–180 and 180–425 μm). It was shown that matrices containing smaller particle sizes of polyox produced harder tablets than when larger polyox particles were used. The release studies showed that matrices consisting of large polyox particles showed a faster release rate than matrices made from smaller particles. Molecular weight (MW) of the polymer was a key determining step in attaining sustained release, with the high MW of polyox resulting in a delayed release profile. The results showed that the effect of particle size on drug release was more detrimental when a low concentration of polyox was used. This indicates that care must be taken when low levels of polyox with different particle size fractions are used. More robust formulations could be obtained when the concentration of polyox is high. Differential scanning calorimetry (DSC) traces showed that particle size had no major effect on the thermal behaviour of polyox particles.KEY WORDS: DSC traces, particle size, polyox, sustained release, theophylline  相似文献   
993.
The interactions of small leucine-rich proteoglycans (SLRPs) with collagen fibrils, their association with water, and their role in fibrillogenesis suggests that SLRPs may play an important role in tendon mechanics. Some studies have assessed the role of SLRPs in the mechanical response of the tendon, but the relationships between sophisticated mechanics, assembly of collagen, and SLRPs have not been well characterized. Decorin content was varied in a dose dependent manner using decorin null, decorin heterozygote, and wild type mice. Quantitative measures of mechanical (tension and compression), compositional, and structural changes of the mouse patellar tendon were evaluated. Viscoelastic, tensile dynamic modulus was increased in the decorin heterozygous tendons compared to wild type. These tendons also had a significant decrease in total collagen and no structural changes compared to wild type. Decorin null tendons did not have any mechanical changes; however, a significant decrease in the average fibril diameter was found. No differences were seen between genotypes in elastic or compressive properties, and all tendons demonstrated viscoelastic mechanical dependence on strain rate and frequency. These results suggest that decorin, a member of the SLRP family, plays a role in tendon viscoelasticity that cannot be completely explained by its role in collagen fibrillogenesis. In addition, reductions in decorin do not cause large changes in indentation compressive properties, suggesting that other factors contribute to these properties. Understanding these relationships may ultimately help guide development of tissue engineered constructs or treatment modalities.  相似文献   
994.
995.
Cadmium (Cd(2+) ) causes alteration of the cellular homeostasis and oxidative damage. The aim of the present study was to investigate the possible protective role of thymoquinone (TQ), a predominant bioactive component present in black seed oil (Nigella sativa) on the hepatotoxicity of Cd(2+) with special reference to its protection against perturbation of nonenzymatic and enzymatic antioxidants. The effect of TQ pretreatment was examined in postnuclear supernatant prepared from liver of Swiss albino mice under in vitro conditions. CdCl(2) treatment (5 mM) resulted in a significant increase in antioxidant enzymatic activities. It also caused a significant (p < 0.001) increase in protein carbonyl and reduced glutathione content. Pretreatment with TQ (10 μM) showed a significant protection as manifested by noticed attenuation of protein oxidation and rejuvenation of the depleted antioxidants of cellular fraction. These results strengthen the hypothesis that TQ exerts modulatory influence on the antioxidant defense system on being subjected to toxic insult.  相似文献   
996.
997.
Occurrences of Late Permian coiled nautiloids are widespread but they have never been analysed in terms of spatial and temporal disparity changes. Morphometric analyses using the cardinal Raupian conch parameters: conch width index, umbilical width index and whorl expansion rate with subsequent analysis by using principal components analysis and non-metric multidimensional scaling, allow the construction of a nautiloid morphospace. The analyses show that there is a stable disparity in the coiled nautiloids from the Wuchiapingian to the Changhsingian. Differences between the three major Late Permian nautiloid occurrences (Salt Range, South China and Transcaucasus-NW Iran) are considerably small; the South Chinese occurrences, however, are characterized by many endemic genera. The most important variation in morphospace occupation is caused by environmental differences such as water depth.  相似文献   
998.
Marine sponges are found to be a rich source of bioactive compounds which show a wide range of biological activities including antiviral, antibacterial, and anti-inflammatory activities. This study aimed to investigate the possible anti-inflammatory, antioxidant and immunomodulator effects of the methanolic extract of the Red Sea marine sponge Xestospongia testudinaria. The chemical composition of the Xestospongia testudinaria methanolic extract was determined using Gas chromatography-mass spectroscopy (GC-MS) analysis. DPPH (2, 2-diphenyl-1-picryl-hydrazyl) was measured to assess the antioxidant activity of the sponge extract. Carrageenan-induced rat hind paw edema was adopted in this study. Six groups of rats were used: group1: Control, group 2: Carrageenan, group 3: indomethacin (10 mg/kg), group 4–6: Xestospongia testudinaria methanolic extract (25, 50, and 100 mg/kg). Evaluation of the anti-inflammatory activity was performed by both calculating the percentage increase in paw weight and hisopathologically. Assessment of the antioxidant and immunomodulatory activity was performed. GC-MS analysis revealed that there were 41 different compounds present in the methanolic extract. Sponge extract exhibited antioxidant activity against DPPH free radicals. Xestospongia testudinaria methanolic extract (100 mg/kg) significantly decreased % increase in paw weight measured at 1, 2, 3 and 4 h after carrageenan injection. Histopathologically, the extract caused a marked decrease in the capillary congestion and inflammatory cells infiltrate. The extract decreased paw malondialdehyde (MDA) and nitric oxide (NO) and increased the reduced glutathione (GSH), glutathione peroxidase (GPx), and catalase (CAT) activity. It also decreased the inflammatory cytokines, tumor necrosis factor-α (TNF-α), interleukin-1 β(IL-1β) and IL-6. The results of this study demonstrated the anti-inflammatory, antioxidant, and immunomodulatory effects of the methanolic extract of the Red Sea sponge Xestospongia testudinaria (100 mg/kg).  相似文献   
999.
Common cocklebur has several biotypes including multiple seeded cocklebur (MSC), NCC-TX, and NCC-MS. Alternaria helianthi applied at 2.5×104 conidia mL-1 in a 50% micro-emulsion of unrefined corn oil (MESUCO) or 0.2% Silwet L 77 caused 60-75% mortality on NCC-TX and MSC. Increasing the conidial concentration to 5×104 mL-1 increased mortality to 100% on MSC and NCC-TX, and 75% on NCC-MS. At 10×104 conidia mL-1, A. helianthi caused 100% mortality in all three biotypes. No mortality occurred in any biotype at inoculation rates of 2.5 and 5×104 conidia mL-1 when applied in water. Increasing the dew period from 0 to 12 h increased mortality from 0 to 100% on all three biotypes at a rate of 2.5×104 conidia mL-1 in Silwet and MESUCO. MSC appears to be the most sensitive biotype.  相似文献   
1000.
The present study was carried out to determine the best pre-sowing treatments that can enhance the germination and seedling growth of Parkia biglobosa (Jacq.) Also, to establish and long-term maintenance of calli and cell suspension cultures . The result of various pre-sowing treatments showed that seeds soaked in concentrated H2SO4 treatment appeared the highest germination percentage, higher value of plant height, number of leaves, number of branches and stem girth. The MS medium containing 1mg/l 2, 4-D was the best for callus induction of stem explants. The addition of 50 mg /l citric acid to the MS medium was effective for reducing browning of callus than other treatments. However, the viability percent recorded the maximum (87.76%) on the 9th day while the concentration of viable cells per ml reached the higher record (137.5 viable cell/ml) at the 12th and cell viability remains (≈ 68.39%) throughout 18 days of culture  相似文献   
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