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191.
BACKGROUND: Immunotherapy using dendritic cell (DC) vaccine has the potential to overcome the bottleneck of cancer therapy. METHODS: We engineered Lewis lung cancer cells (LLCs) and bone marrow–derived DCs to express tumor-associated antigen (TAA) ovalbumin (OVA) via lentiviral vector plasmid encoding OVA gene. We then tested the antitumor effect of modified DCs both in vitro and in vivo. RESULTS: The results demonstrated that in vitro modified DCs could dramatically enhance T-cell proliferation (P < .01) and killing of LLCs than control groups (P < .05). Moreover, modified DCs could reduce tumor size and prolong the survival of LLC tumor-bearing mice than control groups (P < .01 and P < .01, respectively). Mechanistically, modified DCs demonstrated enhanced homing to T-cell–rich compartments and triggered more naive T cells to become cytotoxic T lymphocytes, which exhibited significant infiltration into the tumors. Interestingly, modified DCs also markedly reduced tumor cells harboring stem cell markers in mice (P < .05), suggesting the potential role on cancer stem-like cells. CONCLUSION: These findings suggested that DCs bioengineered with TAA could enhance antitumor effect and therefore represent a novel anticancer strategy that is worth further exploration.  相似文献   
192.
BACKGROUND: The aim of this study is to summarize and quantify the current evidence on the therapeutic efficacy of laparoscopic radical nephrectomy (LRN) compared with open radical nephrectomy (ORN) in patients with renal cell carcinoma (RCC) in a meta-analysis. METHODS: Data were collected by searching Pubmed, Embase, Web of Science, and ScienceDirect for reports published up to September 26, 2016. Studies that reported data on comparisons of therapeutic efficacy of LRN and ORN were included. The fixed-effects model was used in this meta-analysis if there was no evidence of heterogeneity; otherwise, the random-effects model was used. RESULTS: Thirty-seven articles were included in the meta-analysis. The meta-analysis showed that the overall mortality was significantly lower in the LRN group than that in the ORN group (odds ratio [OR] =0.77, 95% confidence interval [CI]: 0.62-0.95). However, there was no statistically significant difference in cancer-specific mortality (OR = 0.77, 95% CI: 0.55-1.07), local tumor recurrence (OR = 0.86, 95% CI: 0.65-1.14), and intraoperative complications (OR = 1.27, 95% CI: 0.83-1.94). The risk of postoperative complications was significantly lower in the LRN group (OR = 0.71, 95% CI: 0.65-0.78). In addition, LRN has been shown to offer superior perioperative results to ORN, including shorter hospital stay days, time to start oral intake, and convalescence time, and less estimated blood loss, blood transfusion rate, and anesthetic consumption. CONCLUSION: LRN was associated with better surgical outcomes as assessed by overall mortality and postoperative complications compared with ORN. LRN has also been shown to offer superior perioperative results to ORN.  相似文献   
193.
Wnt signals have been shown to be involved in multiple steps of vertebrate neural patterning, yet the relative contributions of individual Wnts to the process of brain regionalization is poorly understood. Wnt1 has been shown in the mouse to be required for the formation of the midbrain and the anterior hindbrain, but this function of wnt1 has not been explored in other model systems. Further, wnt1 is part of a Wnt cluster conserved in all vertebrates comprising wnt1 and wnt10b, yet the function of wnt10b during embryogenesis has not been explored. Here, we report that in zebrafish wnt10b is expressed in a pattern overlapping extensively with that of wnt1. We have generated a deficiency allele for these closely linked loci and performed morpholino antisense oligo knockdown to show that wnt1 and wnt10b provide partially redundant functions in the formation of the midbrain-hindbrain boundary (MHB). When both loci are deleted, the expression of pax2.1, en2, and her5 is lost in the ventral portion of the MHB beginning at the 8-somite stage. However, wnt1 and wnt10b are not required for the maintenance of fgf8, en3, wnt8b, or wnt3a expression. Embryos homozygous for the wnt1-wnt10b deficiency display a mild MHB phenotype, but are sensitized to reductions in either Pax2.1 or Fgf8; that is, in combination with mutant alleles of either of these loci, the morphological MHB is lost. Thus, wnt1 and wnt10b are required to maintain threshold levels of Pax2.1 and Fgf8 at the MHB.  相似文献   
194.
Since multiresistant bacterial strains are more widespread and the victim numbers steadily increase, it is very important to possess a broad bandwidth of antimicrobial substances. Antibiotics often feature membrane-associated effect mechanisms. So, we present a membrane proteomic approach to shed light on the cellular response of Escherichia coli as model organism to the hexapeptide MP196, which is arginine and tryptophan rich. Analyzing integral membrane proteins are still challenging, although various detection strategies have been developed in the past. In particular, membrane proteomics in bacteria have been conducted very little due to the special physical properties of these membrane proteins. To obtain more information on the cellular response of the new compound group of small peptides, the tryptophan- and arginine-rich hexapeptide MP196 was subject to a comprehensive quantitative membrane proteomic study on E. coli by means of metabolic labeling in combination with membrane lipid analyses. This study provides in total 767 protein identifications including 185 integral membrane proteins, from which 624 could be quantified. Among these proteins, 134 were differentially expressed. Thereby, functional groups such as amino acid and membrane biosynthesis were affected, stress response could be observed, and the lipid composition of the membrane was significantly altered. Especially, the strong upregulation of the envelope stress induced protein. Spy indicates membrane damage, as well as the downregulation of the mechano-sensitive channel MscL beside others. Finally, the exceptional downregulation of transport systems strengthens these findings.  相似文献   
195.
The use of natural products by communities from the Colombian Caribbean region to treat health issues, together with biodiversity and geographical features, constitute a great scenery to develop new therapies based on ethnopharmacological heritage. Here, we investigated the anti-inflammatory potential of 10 commonly used plants in Colombian folk medicine, evaluating their effect on nitric oxide (NO) production by LPS-stimulated RAW 264.7 macrophages. The most active plant was evaluated in vivo using 12-O-tetradecanoyl-phorbol-13-acetate (TPA)-induced mouse ear edema, along with its effect on the production of pro-inflammatory mediators in vitro. The extract of Physalis angulata L. calyces showed the highest activity. This extract was fractionated and its dichloromethane fraction (DF) was the most active in vitro, inhibiting the production of NO, prostaglandin E2 (PGE2), interleukin (IL)-1β, IL-6, tumor necrosis factor (TNF)-α and monocyte chemotactic protein (MCP)-1 (CCL2). In vivo, DF showed a significant inhibition of ear edema and myeloperoxidase (MPO) activity, with evident reduction of the leukocyte infiltration into tissue. Our results support the ethnopharmacological use of the selected plants in folk medicine. P. angulata dichloromethane fraction represents a promising source of pharmacological compounds with great potential therapeutic use to treat inflammatory illness.  相似文献   
196.
ObjectiveThe present study aims to simulate an alarm system for online detecting normal electrocardiogram (ECG) signals from abnormal ECG so that an individual's heart condition can be accurately and quickly monitored at any moment, and any possible serious dangers can be prevented.Materials and methodsFirst, the data from Physionet database were used to analyze the ECG signal. The data were collected equally from both males and females, and the data length varied between several seconds to several minutes. The heart rate variability (HRV) signal, which reflects heart fluctuations in different time intervals, was used due to the low spatial accuracy of ECG signal and its time constraint, as well as the similarity of this signal with the normal signal in some diseases. In this study, the proposed algorithm provided a return map as well as extracted nonlinear features of the HRV signal, in addition to the application of the statistical characteristics of the signal. Then, artificial neural networks were used in the field of ECG signal processing such as multilayer perceptron (MLP) and support vector machine (SVM), as well as optimal features, to categorize normal signals from abnormal ones.ResultsIn this paper, the area under the curve (AUC) of the ROC was used to determine the performance level of introduced classifiers. The results of simulation in MATLAB medium showed that AUC for MLP and SVM neural networks was 89.3% and 94.7%, respectively. Also, the results of the proposed method indicated that the more nonlinear features extracted from the ECG signal could classify normal signals from the patient.ConclusionThe ECG signal representing the electrical activity of the heart at different time intervals involves some important information. The signal is considered as one of the common tools used by physicians to diagnose various cardiovascular diseases, but unfortunately the proper diagnosis of disease in many cases is accompanied by an error due to limited time accuracy and hiding some important information related to this signal from the physicians' vision leading to the risks of irreparable harm for patients. Based on the results, designing the proposed alarm system can help physicians with higher speed and accuracy in the field of diagnosing normal people from patients and can be used as a complementary system in hospitals.  相似文献   
197.
198.
摘要 目的:探讨肺炎3号联合金银花治疗儿童肺炎对患儿呼吸功能和炎症反应水平影响。方法:选取我院2017年2月-2019年4月期间收治的80例肺炎患儿,随机分成对照组和观察组,每组40例,对照组患儿采取阿奇霉素治疗,观察组患儿采取肺炎3号联合金银花治疗,对比不同治疗方法对患儿呼吸功能和炎症反应水平影响。结果:两组患儿治疗前用力肺活量(forced vital capacity,FVC)、第1秒用力呼气容积(orced expiratory volume in 1 second,FEV1)、用力呼气峰流速(expiratory peak flow rate,PEF)对比无统计学差异(P>0.05),治疗后,观察组患儿上述肺功能指标均明显高于对照组(P<0.05)。两组治疗前患儿血清肿瘤坏死因子(tumor necrosis factor-α,TNF-α)、白介素(interleukin,IL)-6、IL-10对比无统计学差异(P>0.05),治疗后,观察组患儿TNF-α、IL-6均明显低于对照组,且观察组IL-10明显高于对照组(P<0.05)。患儿啰音消失时间、止咳时间、气促消失时间、热退时间以及住院时间对比发现对照组明显长于观察组(P<0.05)。在治疗总效率方面,观察组明显更高(P<0.05)。结论:儿童肺炎采取肺炎3号联合金银花治疗效果确切,可明显改善患儿呼吸功能,抑制机体炎性细胞因子,有效改善患儿临床症状,具有一定临床意义。  相似文献   
199.

Background

According to Regulation (EU) No 619/2011, trace amounts of non-authorised genetically modified organisms (GMO) in feed are tolerated within the EU if certain prerequisites are met. Tolerable traces must not exceed the so-called ‘minimum required performance limit’ (MRPL), which was defined according to the mentioned regulation to correspond to 0.1% mass fraction per ingredient. Therefore, not yet authorised GMO (and some GMO whose approvals have expired) have to be quantified at very low level following the qualitative detection in genomic DNA extracted from feed samples. As the results of quantitative analysis can imply severe legal and financial consequences for producers or distributors of feed, the quantification results need to be utterly reliable.

Results

We developed a statistical approach to investigate the experimental measurement variability within one 96-well PCR plate. This approach visualises the frequency distribution as zygosity-corrected relative content of genetically modified material resulting from different combinations of transgene and reference gene Cq values. One application of it is the simulation of the consequences of varying parameters on measurement results. Parameters could be for example replicate numbers or baseline and threshold settings, measurement results could be for example median (class) and relative standard deviation (RSD). All calculations can be done using the built-in functions of Excel without any need for programming. The developed Excel spreadsheets are available (see section ‘Availability of supporting data’ for details). In most cases, the combination of four PCR replicates for each of the two DNA isolations already resulted in a relative standard deviation of 15% or less.

Conclusions

The aims of the study are scientifically based suggestions for minimisation of uncertainty of measurement especially in —but not limited to— the field of GMO quantification at low concentration levels. Four PCR replicates for each of the two DNA isolations seem to be a reasonable minimum number to narrow down the possible spread of results.

Electronic supplementary material

The online version of this article (doi:10.1186/s12859-014-0407-x) contains supplementary material, which is available to authorized users.  相似文献   
200.
A total of 42 benzyl- and pyridylmethyl amines were synthesized either by reductive amination of aromatic/heteroaromatic aldehydes with amines or by conjugate addition of amines to the cinnamates followed by reduction of the ester group with lithium aluminium hydride to the respective propanolamines. All the synthesized compounds were evaluated against both avirulent and virulent strains of Mycobacterium tuberculosis. Many of the compounds exhibited MIC as low as 1.56 μg/mL. Few of potent compounds were also evaluated against clinical isolates of MDR TB and found to be active at one or other concentrations with MIC as low as 3.12 μg/mL.  相似文献   
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