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91.
Black rice is a functional food that is high in anthocyanin content, primarily C3G and P3G. It possesses nutraceutical properties that exhibit a range of beneficial effects on human health. Currently, the spike glycoprotein S1 subunit of SARS-CoV-2 (SP) has been reported for its contribution to pathological inflammatory responses in targeting lung tissue and innate immune cells during COVID-19 infection and in the long-COVID phenomenon. Our objectives focused on the health benefits of the C3G and P3G-rich fraction of black rice germ and bran (BR extract) on the inhibition of inflammatory responses induced by SP, as well as the inhibition of NF-kB activation and the NLRP3 inflammasome pathway in an in vitro model. In this study, BR extract was identified for its active anthocyanins, C3G and P3G, using the HPLC technique. A549-lung cells and differentiated THP-1 macrophages were treated with BR extract, C3G, or P3G prior to exposure to 100 ng/mL of SP. Their anti-inflammatory properties were then determined. BR extract at concentrations of 12.5–100 μg/mL exhibited anti-inflammation activity for both A549 and THP-1 cells through the significant suppression of NLRP3, IL-1β, and IL-18 inflammatory gene expressions and IL-6, IL-1β, and IL-18 cytokine secretions in a dose-dependent manner (p < 0.05). It was determined that both cell lines, C3G and P3G (at 1.25–10 μg/mL), were compatibly responsible for the significant inhibition of SP-induced inflammatory responses for both gene and protein levels (p < 0.05). With regard to the anti-inflammation mechanism, BR extract, C3G, and P3G could attenuate SP-induced inflammation via counteraction with NF-kB activation and downregulation of the inflammasome-dependent inflammatory pathway proteins (NLRP3, ASC, and capase-1). Overall, the protective effects of anthocyanins obtained from black rice germ and bran can be employed in potentially preventive strategies that use pigmented rice against the long-term sequelae of COVID-19 infection.  相似文献   
92.
Nanoparticles (NPs) are increasingly being commercialized for use in biomedicine. NP toxicity following acute or chronic exposure has been described, but mechanistic insight into this process remains incomplete. Recent evidence from in vitro studies suggested a role for NLRP3 in NP cytotoxicity. In this study, we investigated the effect of systemic administration of composite inorganic NP, consisting of Ag:Cu:B (dose range 1–20?mg/kg), on the early acute (4–24?h post-exposure) and late phase response (96?h post-exposure) in normal and NLRP3-deficient mice. Our findings indicate that systemic exposure (≥2?mg/kg) was associated with acute liver injury due to preferential accumulation of NP in this organ and resulted in elevated AST, ALT and LDH levels. Moreover, within 24?h of NP administration, there was a dose-dependent increase in intraperitoneal neutrophil recruitment and upregulation in gene expression of several proinflammatory mediators, including TNF-α, IL-1β and S100A9. Histological analysis of liver tissue revealed evidence of dose-dependent hepatocyte necrosis, increase in sinusoidal Kupffer cells, lobular granulomas and foci of abscess formation which were most pronounced at 24?h following NP administration. NP deposition in the liver led to a significant upregulation in gene expression of S100A9, an endogenous danger signal recognition molecule of phagocytes, IL-1β and IL-6. The extent of proinflammatory cytokine activation and hepatotoxicity was significantly attenuated in mice deficient in the NLRP3 inflammasome, demonstrating the critical role of this innate immune system recognition receptor in the response to NP.  相似文献   
93.
采用两种新选择性保护方法由L-丝氨酸和α-酮戊二酸为原料经几步合成了8个目标化合物。体外抑菌该验表明除TMV外,对金葡球菌209P和大肠杆菌44822具有中等到强的活性。  相似文献   
94.
目的 研究乌鲁木齐地区非综合征性聋患者线粒体12S rRNA基因突变情况。方法 收集乌鲁木齐非综合征性聋患者标本609例,对其进行临床和分子遗传学评估。结果 12S rRNA基因突变分析共发现11个突变位点,已知的A1555G、961DelT、C1494T突变分别占2.96%,1.15%,0.16%。另外A1047G突变相关报道较少,A1585G突变未见相关报道。其他突变均为多态性位点。结论 线粒体12S rRNA突变是引起遗传性聋的重要因素,此次乌鲁木齐地区线粒体12S rRNA A1555G突变在聋病人群中的检出率与前期报道相比有所降低,可能与耳毒性药物使用量降低有关。A1047G与新发现的A1585G突变是否与聋相关,还需进一步研究。对筛查中阳性突变携带者及其母系家庭成员需告知氨基糖苷类抗生素使用风险,使其避免使用,逐步降低药物性聋的发生率。  相似文献   
95.
In rats, an injection of streptozotocin (STZ) elevated blood levels of glucose 4 weeks later (STZ-induced diabetes) and an over-production of microvessels of retinal and choroidal capillaries of eyes developed. A previous study has shown that administration of Stephania tetrandra S. Moore (STSM) in culture prevented the over-production of microvessels of those capillaries of STZ-induced diabetes in vitro. Therefore, the study investigated whether or not orally administered STSM could inhibit over-production of microvessels of those capillaries of STZ injected rats in vivo. When STSM was given at the same time as the STZ injection and continued daily for 7 weeks, STSM prevented the elevation of blood glucose level and over-production of microvessels of those capillaries. When STSM was given after elevation of blood glucose level of glucose (4 weeks after STZ injection) and continued daily for 4 weeks, STSM lowered the elevated blood glucose level but had no effect on the over-production of microvessels of those capillaries. It was inferred that deposition of N(epsilon)(carboxymethyl) lysine in retinal and choroidal tissues, which is induced by STZ-induced diabetes may deteriorate the blood-retinal barrier and the blood-choroidal barrier. One might, therefore, speculate that advanced STZ-induced diabetes may deteriorate the blood-retinal barrier and blood-choroidal barrier. Therefore, STSM may not reach the retinal and choroidal tissues in the posterior ocular region in vivo.  相似文献   
96.
It is recognized that risks are incurred when health care workers contact various body fluids. The handling of suction collection equipment poses a risk because it is one way workers may come in contact with these fluids. Minimizing the risks associated with suction procedures can be accomplished if appropriate policies and procedures can be developed in health care facilities.  相似文献   
97.
Studies of magnesium kinetics in plasma, red cells, and the whole-body with 28Mg are described. The observations in plasma were analyzed with a three-compartment model and those in red cells with a two-compartment model. An integral approach, using the occupancy principle, was used in the analysis of the whole-body observations. At 120 hr after intravenous administration of 28Mg, exchangeable magnesium calculated by the dilution principle was only 23% of total body magnesium. There was good agreement between the estimates of exchangeable magnesium based on plasma and “spot” urine 28Mg activity. Exchangeable magnesium, as estimated by compartmental analysis and the occupancy principle, was only 12.5%–15% of total body magnesium. These results suggest the existence of magnesium compartments in the body with turnover half-periods of at least 63–181 days that cannot be investigated adequately with the short-lived tracer, 28Mg. A possible mechanism for the observed pattern of red cell uptake of 28Mg in vivo is suggested in which magnesium enters these cells only during erythropoiesis and is then lost progressively from circulating red cells during the aging process. Present results suggest that the concentration of magnesium in reticulocytes may be 3.9 times greater than the mean red cell concentration. Magnesium may leave red cells exponentially with age; a half-period of 22.4 days is suggested.  相似文献   
98.
目的探讨S-100蛋白检测在轻型脑损伤患者中的临床应用价值。方法选择80例格拉斯哥昏迷(GCS)评分在13—15分间的头部外伤病人,进行头部CT扫描和使用电化学发光法检测病人血清S-100蛋白水平,并进行统计学分析。结果34例病人血清S-100蛋白呈阳性,占42%,其中4例病人CT呈阳性占5%;46例病人血清S-100蛋白呈阴性占58%,CT检查均呈阴性。以cT阳性作为脑损伤的判断标准相比较,S-100蛋白的灵敏度为100%,阴性预测值为100%。结论S-100蛋白检测能更好的预测头部外伤病人的颅内出血情况。  相似文献   
99.
胫骨交锁髓内钉术后感染分析   总被引:6,自引:1,他引:6  
目的:探讨胫腌骨骨折交锁髓内钉术后感染的预防与治疗方法。方法;对12例术后感染的病例进行回顾性分析。3例经过抗菌素治疗,9例经过闭式滴不引流加抗菌素治疗,结果;全部病例获随访,随访时间10个月-2年,感染控制,骨折愈合,结论:对胫骨交锁髓内钉术后感染的病人,不必急于取出内固定,采用闭式滴注引流加抗菌素治疗可获得满意效果。  相似文献   
100.
肿瘤转移相关基因的研究进展   总被引:1,自引:0,他引:1  
王晓红 《医学综述》2008,14(21):3246-3248
肿瘤的分化、侵袭和转移等一系列病理过程受多种基因的调控,它们在肿瘤细胞浸润和转移机制中或被激活,或被抑制,相互协同或拮抗,最终影响肿瘤细胞的生物学特性。nm23基因抑制肿瘤转移,而CD44v、S100A4基因和TIAM1基因促进肿瘤的扩散。  相似文献   
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