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921.
Background
Early fluid resuscitation is vital to patients with sepsis. However, the choice of fluid has been a hot topic of discussion. The objective of this study was to evaluate whether the use of albumin-containing fluids for resuscitation in patients with sepsis was associated with a decreased mortality rate.Methods
We systematically searched PubMed, EMBASE and Cochrane library for eligible randomized controlled trials (RCTs) up to March 2014. The selection of eligible studies, assessment of methodological quality, and extraction of all relevant data were conducted by two authors independently.Results
In total, 15 RCTs were eligible for analysis. After pooling the data, we found there was no significant effect of albumin-containing fluids on mortality in patients with sepsis of any severity (RR: 0.94, 95% CI: 0.87, 1.02 and RD: –0.01, 95% CI: –0.03, 0.01). The results were robust to subgroup analyses, sensitivity analyses and trial sequential analyses.Conclusion
The present meta-analysis did not demonstrate significant advantage of using albumin-containing fluids for resuscitation in patients with sepsis of any severity. Given the cost-effectiveness of using albumin, crystalloids should be the first choice for fluid resuscitation in septic patients. 相似文献922.
Meng?Yu Kaizhao?Zhang Wenbao?Qi Zhiqiang?Huang Jinhui?Ye Yongjiang?Ma Ming?LiaoEmail author Zhangyong?NingEmail author 《Virology journal》2014,11(1):229
Background
H9N2 avian influenza virus (AIV) becomes the focus for its ability of transmission to mammals and as a donor to provide internal genes to form the new epidemic lethal influenza viruses. Residue 627 in PB2 has been proven the virulence factor of H9N2 avian influenza virus in mice, but the detailed data for inflammation difference between H9N2 virus strains with site 627 mutation is still unclear. The inflammasome NLRP3 is recently reported as the cellular machinery responsible for activation of inflammatory processes and plays an important role during the development of inflammation caused by influenza virus infection.Methods
In this study, we investigated the expression pattern of NLRP3 and its related cytokines of IL-1β and TNF-α in BALB/c mice infected by H9N2 AIV strains with only a site 627 difference at both mRNA and protein levels at different time points.Results
The results showed that the expression level of NLRP3, IL-1β and TNF-α changed in the lung and brain of BALB/c mice after infection by VK627 and rVK627E. The immunohistological results showed that the positive cells of NLRP3, IL-1β and TNF-α altered the positive levels of original cells in tissues and infiltrated inflammatory cells which caused by H9N2 infection.Conclusions
Our results provided the basic data at differences in expression pattern of NLRP3 and its related cytokines in BALB/c mice infected by H9N2 influenza viruses with only a site 627 difference. This implied that NLRP3 inflammasome plays a role in host response to influenza virus infection and determines the outcome of clinical manifestation and pathological injury. This will explain the variable of pathological presentation in tissues and enhance research on inflammation process of the AIV H9N2 infection.923.
Treatment of hypoxic-ischemic encephalopathy in mouse by transplantation of embryonic stem cell-derived cells 总被引:12,自引:0,他引:12
Ma J Wang Y Yang J Yang M Chang KA Zhang L Jiang F Li Y Zhang Z Heo C Suh YH 《Neurochemistry international》2007,51(1):57-65
A 7-day-old hypoxic-ischemic encephalopathy (HIE) mouse model was used to study the effect of transplantation of embryonic stem (ES) cell-derived cells on the HIE. After the inducement in vitro, the ES cell-derived cells expressed Nestin and MAP-2, rather than GFAP mRNA. After transplantation, ES cell-derived cells can survive, migrate into the injury site, and specifically differentiate into neurons, showing improvement of the learning ability and memory of the HIE mouse at 8 months post-transplantation. The non-grafted HIE mouse brain showed typical pathological changes in the hippocampus and cerebral cortex, where the number of neurons was reduced, while in the cell graft group, number of the neurons increased in the same regions. Although further study is necessary to elucidate the precise mechanisms responsible for this functional recovery, we believe that ES cells have advantages for use as a donor source in HIE. 相似文献
924.
Uroplakins and cytokeratins in the regenerating rat urothelium after sodium saccharin treatment 总被引:5,自引:2,他引:5
A sodium saccharin (NaSac) diet was used to induce cell damage and regeneration in the urothelium of the male rat urinary
bladder. Foci of terminally differentiated superficial cell exfoliation were detected after 5 weeks and their number increased
after 10 and 15 weeks of the diet. At the sites of superficial cell loss, regenerative simple hyperplasia developed. Within
5 weeks of NaSac removal, regeneration re-established normal differentiated urothelium. In order to follow urothelial differentiation
during regeneration we studied the expression of uroplakins and cytokeratins by means of immunocytochemistry and immunohistochemistry,
respectively. Normal urothelium was characterised by terminally differentiated superficial cells which expressed uroplakins
in their luminal plasma membrane and cytokeratin 20 (CK20) in the cytoplasm. Basal and intermediate cells were CK20 negative
and cytokeratin 17 (CK17) positive. In hyperplastic urothelium all cells synthesised CK17, but not CK20. Differentiation of
the superficial layer was reflected in three successive cell types: cells with microvilli, cells with rounded microridges
and those with a rigid-looking plasma membrane on the luminal surface. The cells with microvilli did not stain with anti-uroplakin
antibody. When the synthesis of uroplakins was detected rounded microridges were formed. With the elevated expression of uroplakins
the luminal plasma membrane becomes rigid-looking which is characteristic of asymmetric unit membrane of terminally differentiated
cells. During differentiation, syn-thesis of CK17 ceased in superficial cells while the synthesis of CK20 started. These results
indicate that during urothelial regeneration after NaSac treatment, specific superficial cell types develop in which the switch
to uroplakin synthesis and transition from CK17 to CK20 synthesis are crucial events for terminal differentiation.
Accepted: 19 August 1997 相似文献
925.
926.
Qingdai Liu Xiaoqian Ma Haijiao Cheng Ning Xu Jun Liu Yanhe Ma 《Biotechnology letters》2017,39(6):913-919
Objectives
To improve the production of α-ketoglutaric acid (α-KG) from l-glutamate by whole-cell biocatalysis.Results
A novel and highly active l-glutamate oxidase, SmlGOX, from Streptomyces mobaraensis was overexpressed and purified. The recombinant SmlGOX was approx. 64 kDa by SDS-PAGE. SmlGOX had a maximal activity of 125 ± 2.7 U mg?1 at pH 6.0, 35 oC. The apparent Km and Vmax values of SmlGOX were 9.3 ± 0.5 mM and 159 ± 3 U mg?1, respectively. Subsequently, a co-expression plasmid containing the SmlGOX and KatE genes was constructed to remove H2O2, and the protein levels of SmlGOX were improved by codon optimization. Finally, by optimizing the whole-cell transformation conditions, the production of α-KG reached 77.4 g l?1 with a conversion rate from l-glutamate of 98.5% after 12 h.Conclusions
An efficient method for the production of α-KG was established in the recombinant Escherichia coli, and it has a potential prospect in industrial application.927.
928.
To study influence of wheat straw returning mode on CH4 emission from paddy soils, a field experiment was conducted at Jurong, Jiangsu Province, China in 2006. Five treatments, no wheat straw applied (CK), wheat straw evenly incorporated into the topsoil (WI), wheat straw buried in ditches (WD), wheat straw strip-mulched onto the field surface (WM) and wheat straw burned in-situ (WB), were laid out in a randomized block design. Results showed that seasonal CH4 emissions ranged from 6.9 to 28.1 g CH4 m?2. Wheat straw incorporation significantly increased CH4 emission. No significant difference was observed between Treatments WI and WD in total CH4 emission. Compared with Treatment WI, Treatment WM reduced total CH4 emission by 32% and Treatment WB by 42%. Treatment WM was about 27% higher than Treatment CK in grain yield. Based on the findings, the best management of wheat straw prior to rice cultivation is strip-mulching wheat straw onto the field surface, which largely reduced CH4 emission from rice fields with no decrease in rice yield. 相似文献
929.
Jing Han Hua Liang Jianhua Yi Wuhong Tan Shulan He Sen Wang Feng Li Xiaofang Wu Jing Ma Xiaowei Shi Xiong Guo Chuanyi Bai 《Biological trace element research》2017,175(2):396-404
The effects of selenium (Se)-deficient diet on the liver were evaluated by using growing rats which were fed with normal and Se-deficient diets, respectively, for 109 days. The results showed that rats fed with Se-deficient diet led to a decrease in Se concentration in the liver, particularly among male rats from the low-Se group. This causes alterations to the ultrastructure of hepatocytes with condensed chromatin and swelling mitochondria observed after low Se intake. Meanwhile, pathological changes and increased fibrosis in hepatic periportal were detected by hematoxylin and eosin and Masson’s trichrome staining in low-Se group. Furthermore, through immunohistochemistry (IHC) staining, higher expressions of metalloproteinases (MMP1/3) and their tissue inhibitors of metalloproteinases (TIMP1/3) were observed in the hepatic periportal of rats from the low-Se group. However, higher expressions of MMP1/3 and lower expressions of TIMP1/3 were detected in hepatic central vein and hepatic sinusoid. In addition, upregulated expressions of MMP1/3 and downregulated expressions of TIMP1/3 at the messenger RNA (mRNA) and protein levels also appeared to be relevant to low Se intake. In conclusion, Se-deficient diet could cause low Se concentration in the liver, alterations of hepatocyte ultrastructure, differential expressions of MMP1/3 and TIMP1/3 as well as fibrosis in the liver hepatic periportal. 相似文献
930.