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121.
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122.
Enhancement of methane production from cassava residues by biological pretreatment using a constructed microbial consortium 总被引:2,自引:0,他引:2
Qinghua Zhang Jiang HeMin Tian Zhonggui Mao Lei Tang Jianhua ZhangHongjian Zhang 《Bioresource technology》2011,102(19):8899-8906
In the study, a stable thermophilic microbial consortium with high cellulose-degradation ability was successfully constructed. That several species of microbes coexisted in this consortium was proved by DGGE (denaturing gradient gel electrophoresis) and sequence analysis. The cooperation and symbiosis of these microbes in this consortium enhanced their cellulose-degradation ability. The pretreatment of cassava residues mixing with distillery wastewater prior to anaerobic digestion was investigated by using this microbial consortium as inoculums in batch bioreactors at 55 °C. The experimental results showed that the maximum methane yield (259.46 mL/g-VS) of cassava residues was obtained through 12 h of pretreatment by this microbial consortium, which was 96.63% higher than the control (131.95 mL/g-VS). In addition, it was also found that the maximum methane yield is obtained when the highest filter paper cellulase (FPase), carboxymethyl cellulase (CMCase) and xylanase activity and soluble COD (sCOD) are produced. 相似文献
123.
Qing-Qiu Mao Siu-Po Ip Kam-Ming Ko Sam-Hip Tsai Ming Zhao Chun-Tao Che 《Cellular and molecular neurobiology》2009,29(5):643-647
Preclinical and clinical investigations have shown the involvement of dysregulation of hypothalamic–pituitary–adrenal (HPA)
axis in the pathogenesis of depression. Hypercortisolemia and the associated hippocampal atrophy were observed in patients
with depression, which could be ameliorated by the treatment with antidepressants. Therefore, neuroprotection has been proposed
to be one of the acting mechanisms of antidepressant. Previous studies in our laboratory have demonstrated the antidepressant-like
activity of total glycosides of peony (TGP) in mice. This study aimed to examine the effect of TGP treatment on corticosterone-induced
neurotoxicity in cultured rat pheochromocytoma (PC12) cells. Treating the cells with corticosterone at 200 μM for 48 h caused
apoptotic cell death. The cytotoxicity was associated with the activation of caspase-3 activity and the decrease in the mRNA
ratio of bcl-2 to bax. TPG treatment at increasing doses (1–10 mg/l) protected against the corticosterone-induced toxicity
in PC12 cells in a dose-dependent manner. The cytoprotection afforded by TGP treatment was associated with the inhibition
of caspase-3 activity and the up-regulation of bcl-2/bax mRNA ratio. The anti-apoptotic effect of TGP is therefore likely
mediated by the suppression of the mitochondrial pathway leading to apoptosis. 相似文献
124.
Ying Huai Xue Wang Wenjing Mao Xuehao Wang Yipu Zhao Xiaohua Chu Qian Huang Kang Ru Ling Zhang Yu Li Zhihao Chen Airong Qian 《Aging cell》2024,23(3):e14053
Aging impairs osteoblast function and bone turnover, resulting in age-related bone degeneration. Stress granules (SGs) are membrane-less organelles that assemble in response to stress via the recruitment of RNA-binding proteins (RBPs), and have emerged as a novel mechanism in age-related diseases. Here, we identified HuR as a bone-related RBP that aggregated into SGs and facilitated osteogenesis during aging. HuR-positive SG formation increased during osteoblast differentiation, and HuR overexpression mitigated the reduction in SG formation observed in senescent osteoblasts. Moreover, HuR positively regulated the mRNA stability and expression of its target β-catenin by binding and recruiting β-catenin into SGs. As a potential therapeutic target, HuR activator apigenin (API) enhanced its expression and thus aided osteoblasts differentiation. API treatment increased HuR nuclear export, enhanced the recruitment of β-catenin into HuR-positive SGs, facilitated β-catenin nuclear translocation, and contributed osteogenesis. Our findings highlight the roles of HuR and its SGs in promoting osteogenesis during skeletal aging and lay the groundwork for novel therapeutic strategies against age-related skeletal disorders. 相似文献
125.
Weihua Ma Xianxin Zhao Chuanlin Yin Fan Jiang Xiaoyong Du Taiyu Chen Qinghua Zhang Lin Qiu Hongxing Xu J. Joe Hull Guoliang Li Wing‐Kin Sung Fei Li Yongjun Lin 《Molecular ecology resources》2020,20(1):268-282
The rice stem borer, Chilo suppressalis, is one of the most damaging insect pests to rice production worldwide. Although C. suppressalis has been the focus of numerous studies examining cold tolerance and diapause, plant–insect interactions, pesticide targets and resistance, and the development of RNAi‐mediated pest management, the absence of a high‐quality genome has limited deeper insights. To address this limitation, we generated a draft C. suppressalis genome constructed from both Illumina and PacBio sequences. The assembled genome size was 824.35 Mb with a contig N50 of 307 kb and a scaffold N50 of 1.75 Mb. Hi‐C scaffolding assigned 99.2% of the bases to one of 29 chromosomes. Based on universal single‐copy orthologues (BUSCO), the draft genome assembly was estimated to be 97% complete and is predicted to encompass 15,653 protein‐coding genes. Cold tolerance is an extreme survival strategy found in animals. However, little is known regarding the genetic basis of the winter ecology of C. suppressalis. Here, we focused our orthologous analysis on those gene families associated with animal cold tolerance. Our finding provided the first genomic evidence revealing specific cold‐tolerant strategies in C. suppressalis, including those involved in glucose‐originated glycerol biosynthesis, triacylglycerol‐originated glycerol biosynthesis, fatty acid synthesis and trehalose transport‐intermediate cold tolerance. The high‐quality C. suppressalis genome provides a valuable resource for research into a broad range of areas in molecular ecology, and subsequently benefits developing modern pest control strategies. 相似文献
126.
Fei Mao Ling Huang Zonghua Luo Anqiu Liu Chuanjun Lu Zhiyong Xie Xingshu Li 《Bioorganic & medicinal chemistry》2012,20(19):5884-5892
In an effort to identify novel multifunctional drug candidates for the treatment of Alzheimer’s disease (AD), a series of hybrid molecules were synthesised by reacting N-(aminoalkyl)tacrine with salicylic aldehyde or derivatives of 2-aminobenzaldehyde. These compounds were then evaluated as multifunctional anti-Alzheimer’s disease agents. All of the hybrids are potential biometal chelators, and in addition, most of them were better antioxidants and inhibitors of cholinesterases and amyloid-β (Aβ) aggregation than the lead compound tacrine. Compound 7c has the potential to be a candidate for AD therapy: it is a much better inhibitor of acetylcholinesterase (AChE) than tacrine (IC50: 0.55 nM vs 109 nM), has good biometal chelation ability, is able to inhibit Aβ aggregation and has moderate antioxidant activity (1.22 Trolox equivalents). 相似文献
127.
Recent rates of illness and death from asthma in Canada and rates of hospital admission/separation for asthma were examined by age group and region. The death rates were higher in 1982-84 than in 1970-72, especially among those aged 15 to 34 years. Increases were also noted in hospital admission/separation rates, especially among those less than 15 years of age. Hospital admission/separation rates were highest in the Maritime provinces and Saskatchewan, whereas death rates were highest in Alberta and Saskatchewan. Examination of death certificates for coding errors and recoding of certificates to a single (8th) revision of the International Classification of Diseases indicated that changes in disease coding and errors in coding did not account for the significant increase in rates of death from asthma for those aged 15 to 34 years. These increases in rates of illness and death from asthma are unexplained and warrant further investigation. 相似文献
128.
129.
Sebastian F. Barreto-Ortiz Shuming Zhang Matthew Davenport Jamie Fradkin Brian Ginn Hai-Quan Mao Sharon Gerecht 《PloS one》2013,8(11)
In microvascular vessels, endothelial cells are aligned longitudinally whereas several components of the extracellular matrix (ECM) are organized circumferentially. While current three-dimensional (3D) in vitro models for microvasculature have allowed the study of ECM-regulated tubulogenesis, they have limited control over topographical cues presented by the ECM and impart a barrier for the high-resolution and dynamic study of multicellular and extracellular organization. Here we exploit a 3D fibrin microfiber scaffold to develop a novel in vitro model of the microvasculature that recapitulates endothelial alignment and ECM deposition in a setting that also allows the sequential co-culture of mural cells. We show that the microfibers'' nanotopography induces longitudinal adhesion and alignment of endothelial colony-forming cells (ECFCs), and that these deposit circumferentially organized ECM. We found that ECM wrapping on the microfibers is independent of ECFCs'' actin and microtubule organization, but it is dependent on the curvature of the microfiber. Microfibers with smaller diameters (100–400 µm) guided circumferential ECM deposition, whereas microfibers with larger diameters (450 µm) failed to support wrapping ECM. Finally, we demonstrate that vascular smooth muscle cells attached on ECFC-seeded microfibers, depositing collagen I and elastin. Collectively, we establish a novel in vitro model for the sequential control and study of microvasculature development and reveal the unprecedented role of the endothelium in organized ECM deposition regulated by the microfiber curvature. 相似文献
130.
Mao S Lee SJ Hwangbo H Kim YW Park KH Cha GS Park RD Kim KY 《Current microbiology》2006,53(5):358-364
A new antagonistic Burkholderia strain, designated MP-1 and producing antifungal activities against various filamentous plant pathogenic fungi, was isolated
from the rhizoshere in the Naju area. Cultural characteristic studies strongly suggested that this strain belongs to the genus
Burkholderia. The nucleotide sequence of the 16S rRNA gene (1491 pb) of strain MP-1 exhibited close similarity (99% to 100%) with other
Burkholderia 16S rRNA genes. Extraction of fermentation broth of Burkholderia sp. MP-1 and various separations and purification steps led to isolation of four pure active molecules. The chemical structure
of these four compounds—named phenylacetic acid, hydrocinnamic acid, 4-hydroxyphenylacetic acid, and 4-hydroxyphenylacetate
methyl ester—was established on the basis on their gas chromatography–electron impact–mass spectrometry (GC-EI-MS) and trimethylsilation
GC-EI-MS data. The four isolated compounds inhibited filamentous fungal growth on potato dextrose agar medium supplemented
with 100 mg/L of phenylacetic acid, hydrocinnamic acid, 4-hydroxyphenylacetic acid and 4-hydroxyphenylacetate methyl ester
individually. 相似文献