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1.
The aim of this safety study in mice was to determine in vivo toxicity and biodistribution potential of a single and multiple doses of L-glutamic acid-g-p(HEMA) polymeric nanoparticles as a drug delivery system. The single dose did not cause any lethal effect, and its acute oral LD50 was >2.000 mg/kg body weight (bw). Multiple doses (25, 50, or 100 mg/kg bw) given over 28 days resulted in no significant differences in body and relative organ weights compared to control. These results are supported by biochemical and histological findings. Moreover, nanoparticle exposure did not result in statistically significant differences in micronucleus counts in bone marrow cells compared to control. Nanoparticle distribution was time-dependent, and they reached the organs and even bone marrow by hour 6, as established by ex vivo imaging with the IVIS® spectrum imaging system. In conclusion, L-glutamic acid-g-p(HEMA) polymeric nanoparticles appear biocompatible and have a potential use as a drug delivery system.KEY WORDS: biocompatibility, blood biochemistry, genotoxicity, histology, in vivo toxicity, micronucleus test, polymers  相似文献   
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Comprehensive evidence regarding the treatment of non-anaemic iron deficiency in patients undergoing valvular heart surgery is lacking. This study aimed to investigate the association between non-anaemic iron deficiency and postoperative outcomes in these patients. We retrospectively analysed 321 patients of which 180 (56%) had iron deficiency (defined as serum ferritin < 100 ng.ml-1 or < 300 ng.ml-1 with transferrin saturation < 20%). While the iron-deficient group had lower pre-operative haemoglobin levels than the non-iron deficient group (median (IQR [range]) 134 (127–141 [120–172]) g.l-1, 143 (133–150 [120–179]) g.l-1, p = 0.001), there was no between-group difference in allogeneic red blood cell transfusion. Median (IQR [range]) days alive and out of hospital at postoperative day 90 was 1 day shorter in the iron-deficient group (80 (77–82 [9–85]) days vs. 81 (79–83 [0–85]) days, p = 0.026). In multivariable analysis, only cardiopulmonary bypass duration (p = 0.032) and intra-operative allogeneic red blood cell transfusion (p = 0.011) were significantly associated with reduced days alive and out of hospital at postoperative day 90. Iron deficiency did not exert any adverse influence on secondary outcomes except length of hospital stay. Our findings indicate that non-anaemic iron deficiency alone is not associated with adverse effects in patients undergoing valvular heart surgery when it does not translate into an increased risk of allogeneic transfusion.  相似文献   
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Clinical Oral Investigations - The aim of this study was the analysis of WNT10A variants in seven families of probands with various forms of tooth agenesis and self-reported family history of...  相似文献   
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肖瑾  李小军  黄建军  高圣权  陆昌洙  刘向前 《中草药》2020,51(22):5781-5787
目的 研究细柱五加Acanthopanax gracilistylus W.W.Smith中impressic acid(IA)对脂多糖(LPS)诱导的小鼠单核巨噬细胞RAW264.7的抗炎作用。方法 以LPS诱导RAW264.7细胞建立炎症模型;使用EZ4U细胞增殖与细胞毒性分析试剂盒检测IA对RAW264.7细胞的毒性作用;Griess法测定一氧化氮(NO)水平;ELISA法测肿瘤坏死因子-α(TNF-α)、白介素-1β(IL-1β)水平;RT-PCR法检测TNF-α、IL-1β mRNA表达;Western blotting检测高迁移率族蛋白B1(HMGB1)蛋白表达;ELISA法细胞质和细胞核的核因子-κB(NF-κB)水平。结果 Impressic acid可以显著抑制LPS诱导的RAW264.7细胞中TNF-α、IL-1β水平和HMGB1蛋白表达,并抑制NF-κB从细胞质向细胞核的转移(P<0.05、0.01)。结论 细柱五加中IA对LPS诱导的RAW264.7细胞具有抗炎作用。  相似文献   
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Immunocompromised populations are at great risk of the current 2020 global emergency of coronavirus disease 2019 (COVID-19), and treatment of kidney transplant recipients with COVID-19 is currently not declared. Hence, the purpose of the study is to set a clear treatment regimen. We report here a therapeutic course of 2 patients who underwent transplant surgery in March 2020 and got infected soon after. Since the transplant, these 2 patients have received triple maintenance immunosuppressive therapy with oral tacrolimus, mycophenolate mofetil (MMF), and prednisone, and they have been regularly followed up at our hospital. The tacrolimus trough level was between 10 and 12 ng/mL. After the diagnosis of COVID-19, MMF was stopped and the tacrolimus dose was reduced so that blood level was between 4 and 6 ng/mL. The first patient was a 30-year-old man who, despite being treated with hydroxychloroquine, favipiravir, oseltamivir, and azithromycin therapy, died because of the presence of other comorbidities. The second case was a 58-year-old man who fully recovered from COVID-19 pneumonia with treatment with methylprednisolone, MMF, azithromycin, favipiravir, hydroxychloroquine, and reduction in immunosuppression dosage. This reflects the importance of using glucocorticoids in the treatment of COVID-19 along with other medications and the decreased mortality rate associated with their use.  相似文献   
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Background

Although it is known that women do not participate in trials as frequently as men, there are limited recent data examining how women recruitment has changed over time.

Methods

We conducted MEDLINE search using a validated strategy for randomized trials published in New England Journal of Medicine, Lancet, and Journal of the American Medical Association between 1986 and 2015, and included trials evaluating pharmacologic or nonpharmacologic therapies. We abstracted data on demographics, intervention type, clinical indication, and trial design characteristics, and examined their relationships with women enrollment.

Results

In total, 598 trials met inclusion criteria. Women enrollment increased significantly over time (21% between 1986 and 1990 to 33% between 2011 and 2015; Pfor trend < 0.001) and did not differ by journal or funding source. Women enrollment varied with clinical indication, comprising 37% for non–coronary artery disease vascular trials, 30% for coronary artery disease trials, 28% for heart failure trials, and 28% for arrhythmia trials (P < 0.001), which were all significantly lower than the expected proportion in disease populations (P < 0.001). Women enrollment varied with trial type (31%, 29%, and 26% for pharmacologic, device, and procedural trials, respectively; P = 0.001). These findings were corroborated using multivariable analysis. We found significant positive correlations between women enrolled, and mean age and total number of participants. Fewer women were enrolled in trials reporting statistically significant results than those who did not (P = 0.001).

Conclusions

Although enrollment of women has increased over time, it remains lower than the relative proportion in the disease population. Future studies should elucidate the reasons for persistent under-representation of women in clinical trials.  相似文献   
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