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1.
BackgroundAs an ongoing worldwide health issue, Coronavirus disease 2019 (COVID–19) has been causing serious complications, including pneumonia, acute respiratory distress syndrome (ARDS), and multi-organ failure. However, there is no decisive treatment approach available for this disorder, which is primarily attributed to the large amount of inflammatory cytokine production. We aimed to identify the effects of Nano-curcumin on the modulation of inflammatory cytokines in COVID-19 patients.MethodForty COVID-19 patients and 40 healthy controls were recruited and evaluated for inflammatory cytokine expression and secretion. Subsequently, COVID-19 patients were divided into two groups: 20 patients receiving Nano-curcumin and 20 patients as the placebo group. The mRNA expression and cytokine secretion levels of IL-1β, IL-6, TNF-α and IL‐18 were assessed by Real‐time PCR and ELISA, respectively.ResultOur primary results indicated that the mRNA expression and cytokine secretion of IL-1β, IL-6, TNF-α, and IL-18 were increased significantly in COVID-19 patients compared with healthy control group. After treatment with Nano-curcumin, a significant decrease in IL-6 expression and secretion in serum and in supernatant (P = 0.0003, 0.0038, and 0.0001, respectively) and IL-1β gene expression and secretion level in serum and supernatant (P = 0.0017, 0.0082, and 0.0041, respectively) was observed. However, IL-18 mRNA expression and TNF-α concentration were not influenced by Nano-curcumin.ConclusionNano-curcumin, as an anti-inflammatory herbal based agent, may be able to modulate the increased rate of inflammatory cytokines especially IL-1β and IL-6 mRNA expression and cytokine secretion in COVID-19 patients, which may cause an improvement in clinical manifestation and overall recovery. 相似文献
2.
H.E. Goodis J.M. White G.W. Marshall Jr. K. Yee N. Fuller L. Gee S.J. Marshall 《Archives of oral biology》1997,42(12):845-854
Dentine specimens were prepared from freshly extracted third molars and initial permeability measured. Each specimen was subjected to Nd:yttrium-aluminium-garnet (YAG) (1.06 or 1.32 μm wavelength) or Ho:YAG (2.10 μm wavelength) laser energy while temperatures in the pulp chambers were recorded. Permeability was again measured and the surfaces examined by scanning electron microscopy. Six crown segments were used for each laser variable and eight permeability measurements were taken before and eight after laser exposure, while temperature was recorded during treatment. All wavelengths reduced permeability but temperature rises were high enough to have caused pulpal damage, indicating that shorter treatment times and lower power settings may be necessary if used in vivo. 相似文献
3.
Raquel Matavele Chissumba Abílio Luciano Eduardo Namalango Asli Bauer Nilesh Bhatt Britta Wahren Charlotta Nilsson Christof Geldmacher Gabriella Scarlatti Ilesh Jani Luc Kestens 《Immunobiology》2018,223(12)
Background
Little is known about regulatory CD4 T cells (Tregs) in the context of HIV vaccines. Tregs can be differentiated into resting (FoxP3+CD45RA+ – rTregs), activated (FoxP3HighCD45RA? – aTregs) and memory (FoxP3LowCD45RA? – mTregs). Tregs, as CD4 T cells, are also frequent targets for HIV infection. We studied how the abundance and phenotypes of Tregs in terms of activation status and expression of HIV-1 binding molecules would have changed during vaccination in healthy volunteers participating in a phase IIa HIV vaccine clinical trial. Subjects were primed three times with HIVIS-DNA and boosted twice with MVA-CMDR-HIV alone (n?=?12) or MVA-CMDR combined with protein CN54rgp140 (n?=?13). The proportions of β7 integrin in all CD4 T cells and in the Tregs subset decreased moderately after the final vaccination (p?=?0.001 and p?=?0.033, respectively) and the rTregs proportion within the total Tregs were also decreased after the final vaccination (p?=?0.038). All these proportions returned to normal values within the three months after the final vaccination. The magnitude of HIV-Envelope-specific IFNγ?+?T cells after vaccination (r?=?0.66; p?=?0.021) correlated directly with the proportion of Tregs, and correlated inversely correlated with ratios of Th17/Tregs (r?=??0.75; p?=?0.0057) and Th17/mTregs (r?=??0.78; p?=?0.0065). Higher titers of IgG gp140 antibodies were observed in subjects with higher mTregs proportions (r?=?0.52; p?=?0.022). Interestingly, pre-vaccination levels of mTregs correlated with vaccine-induced Env-binding antibodies (r?=?0.57; p?=?0.01) and presence of neutralizing antibodies (r?=?0.61; p?=?0.01), while the pre-vaccination Th17/mTregs ratio correlated inversely with the magnitude of cellular IFN-γ ELISpot responses (r?=??0.9; p?=?0.002). Taken together, these results suggest that pre- and post-vaccination Tregs, their activation status, the Th17/Tregs ratio and other host factors affecting Treg abundance, have an impact on the magnitude of HIV vaccine-induced immune responses. Moreover, the DNA-HIVIS/MVA-HIV regimen, alone or in combination with CN54rgp140 induced moderate and temporary alterations of the Tregs activation status. We also show a decrease in expression of the HIV-1 ligand β7 integrin on Tregs and all CD4 T cells. 相似文献4.
5.
目的:评估小牛血去蛋白提取物眼用凝胶治疗儿童干眼症的效果。方法:100例(200眼)干眼症儿童被随机平均分为对照组和实验组,对照组用0.1%玻璃酸钠滴眼液,每日4次,实验组用小牛血去蛋白提取物眼用凝胶,每日4次;两组同时针对病因治疗。对比分析治疗前与治疗后30 d的症状评分、泪液分泌试验、泪膜破裂时间(BUT)、角膜荧光素染色评分。结果:两组治疗前、后各项评分比较差异有统计学意义(P<0.05);两组治疗后各项评分比较差异有统计学意义(P<0.05)。结论:小牛血去蛋白提取物眼用凝胶能有效治疗儿童干眼症。 相似文献
6.
Comparison of metabolic adaptations between endurance‐ and sprint‐trained athletes after an exhaustive exercise in two different calf muscles using a multi‐slice 31P‐MR spectroscopic sequence 下载免费PDF全文
Kevin Moll Alexander Gussew Maria Nisser Steffen Derlien Martin Krämer Jürgen R. Reichenbach 《NMR in biomedicine》2018,31(4)
Measurements of exercise‐induced metabolic changes, such as oxygen consumption, carbon dioxide exhalation or lactate concentration, are important indicators for assessing the current performance level of athletes in training science. With exercise‐limiting metabolic processes occurring in loaded muscles, 31P‐MRS represents a particularly powerful modality to identify and analyze corresponding training‐induced alterations. Against this background, the current study aimed to analyze metabolic adaptations after an exhaustive exercise in two calf muscles (m. soleus – SOL – and m. gastrocnemius medialis – GM) of sprinters and endurance athletes by using localized dynamic 31P‐MRS. In addition, the respiratory parameters VO2 and VCO2, as well as blood lactate concentrations, were monitored simultaneously to assess the effects of local metabolic adjustments in the loaded muscles on global physiological parameters. Besides noting obvious differences between the SOL and the GM muscles, we were also able to identify distinct physiological strategies in dealing with the exhaustive exercise by recruiting two athlete groups with opposing metabolic profiles. Endurance athletes tended to use the aerobic pathway in the metabolism of glucose, whereas sprinters produced a significantly higher peak concentration of lactate. These global findings go along with locally measured differences, especially in the main performer GM, with sprinters revealing a higher degree of acidification at the end of exercise (pH 6.29 ± 0.20 vs. 6.57 ± 0.21). Endurance athletes were able to partially recover their PCr stores during the exhaustive exercise and seemed to distribute their metabolic activity more consistently over both investigated muscles. In contrast, sprinters mainly stressed Type II muscle fibers, which corresponds more to their training orientation preferring the glycolytic energy supply pathway. In conclusion, we were able to analyze the relation between specific local metabolic processes in loaded muscles and typical global adaptation parameters, conventionally used to monitor the training status of athletes, in two cohorts with different sports orientations. 相似文献
7.
Giorgia Del Favero Silvio Sosa Mark Poli Aurelia Tubaro Orfeo Sbaizero Paola Lorenzon 《Toxicology letters》2014
Palytoxins (PLTXs) are known seafood contaminants and their entrance into the food chain raises concern about possible effects on human health. The increasing number of analogs being identified in edible marine organisms complicates the estimation of the real hazard associated with the presence of PLTX-like compounds. So far, 42-OH-PLTX is one of the few congeners available, and the study of its toxicity represents an important step toward a better comprehension of the mechanism of action of this family of compounds. From this perspective, the aim of this work was to investigate the in vivo and in vitro effect of 42-OH-PLTX on skeletal muscle, one of the most sensitive targets for PLTXs. Our results demonstrate that 42-OH-PLTX causes damage at the skeletal muscle level with a cytotoxic potency similar to that of PLTX. 42-OH-PLTX induces cytotoxicity and cell swelling in a Na+-dependent manner similar to the parent compound. However, the limited Ca2+-dependence of the toxic insult induced by 42-OH-PLTX suggests a specific mechanism of action for this analog. Our results also suggest an impaired response to the physiological agonist acetylcholine and altered cell elasticity. 相似文献
8.
《Minimally invasive therapy & allied technologies》2013,22(5-6):484-486
Summary. During laparoscopic surgery, intra-abdominal pressure is increased by the pneumoperitoneum. This may impede venous return from the legs and so predispose to venous thrombosis. The aim of this study was to investigate femoral venous velocity and femoral venous diameter during pneumoperitoneum, and to assess the reversibility of this effect by use of an intermittent calf compression device. Fourteen patients undergoing laparoscopic cholecystectomy were studied. A duplex scanner was used to assess femoral venous velocity (both with and without use of a calf compression device), and diameter, before, during and after establishment of a pneumoperitoneum. There was a significant reduction in the femoral venous velocity (from 0.15-0.105 m/s, P<0.01) and a significant increase in femoral venous diameter (from 6.55-9.3 mm, P<0.01) during pneumoperitoneum. The use of a calf compression device reversed this effect (augmented velocity of 0.395 m/s during pneumoperitoneum, P<0.01). These results indicate that laparoscopic surgery affects venous haemodynamics and this effect can be reversed with calf compression devices. 相似文献
9.
10.
目的:研究氚标记小牛胸腺DNA(3H-小牛胸腺DNA)在大鼠和Beagle犬体内的药动学特征。方法:采用氚水交换法制备3H-小牛胸腺DNA。取大鼠尾静脉注射高、中、低剂量(15、5、1.67 mg/kg,n=5)的3H-小牛胸腺DNA,中、高剂量组大鼠连续给药7d(第1、7天给予3H-小牛胸腺DNA,其余时间给予未标记小牛胸腺DNA),低剂量大鼠仅单次给药;另取犬前肢静脉注射高、中、低剂量(1.5、0.5、0.167 mg/kg,n=3)的3H-小牛胸腺DNA,中剂量犬连续给药7 d,低、高剂量犬仅单次给药。分别于第1、7天给药后0.033、0.25、1、2、4、6、8、12、24 h取血,分离血浆后加入闪烁液并使用液闪计数仪分析,以WinNonlin软件计算药动学参数。结果:高、中、低剂量3H-小牛胸腺DNA在大鼠体内的药动学参数分别为:单次给药的AUC0-24 h为(11 742±2 245)、(3 571±851)、(727±202)ng-Eq·h/g,t1/2为(21.4±5.08)、(13±6.0)、(6.8±1.76)h;重复给药高、中剂量的AUC0-24 h为(5 706±1 009)、(7 601±1 861)ng-Eq·h/g,t1/2为(16.0±10.13)、(9±2.7)h。高、中、低剂量3H-小牛胸腺DNA在犬体内的药动学参数分别为:单次给药的AUC0-24 h为(4 444±999)、(2 719±139)、(501±101)ng-Eq·h/g,t1/2为(17.6±7.57)、(14.0±1.76)、(16.4±2.39)h;重复给药中剂量的AUC0-24 h为(3 073±200)ng-Eq·h/g,t1/2为(20.6±6.62)h。结论:3H-小牛胸腺DNA在大鼠与Beagle犬体内单次给药和重复给药均可被快速消除。 相似文献