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1.
The possession of a respiration-dependent primary sodium pump and the requirement of Na for growth were investigated in bacterial isolates from marine environments. The bacteria in which NADH oxidase specifically required Na for maximum activity were believed to possess a primary sodium pump. All bacteria that failed to grow without the addition of NaCl possessed a primary Na pump. All bacteria that had no primary Na pump grew without additional NaCl. The primary Na pump seems to be involved in the Na requirement of marine bacteria, and this can be regarded as a criterion for the definition of marine bacteria.  相似文献   
2.
Manganese (Mn) is an essential trace element, while excessive expose may induce neurotoxicity. Recently, lncRNAs have been extensively studied and it has been confirmed that lncRNAs participate in neural functions and aberrantly expressed lncRNAs are involved in neurological diseases. However, the pathological effects of lncRNAs on Mn-induced neurotoxicity remain unclear. In this study, the expression profiles of lncRNAs and messenger RNAs (mRNAs) were identified in Mn-treated hippocampal neurons and control neurons via microarray. Bioinformatic methods and intersection analysis were also employed. Results indicated that 566, 1161, and 1474 lncRNAs meanwhile 1848, 3228, and 4022 mRNAs were aberrantly expressed in low, intermediate, and high Mn-exposed groups compared with the control group, respectively. Go analysis determined that differentially expressed mRNAs were targeted to biological processes, cellular components, and molecular functions. Pathway analysis indicated that these mRNAs were enriched in insulin secretion, cell cycle, and DNA replication. Intersection analysis denominated that 135 lncRNAs and 373 mRNAs were consistently up-regulated while 150 lncRNAs and 560 mRNAs were consistently down-regulated. Meanwhile, lncRNA BC079195 was significantly up-regulated while lncRNAs uc.229- and BC089928 were significantly down-regulated in three comparison groups. The relative expression levels of 3 lncRNAs and 4 mRNAs were validated through qRT-PCR. To the best of our knowledge, this study is the first to identify the expression patterns of lncRNAs and mRNAs in hippocampal neurons of Sprague–Dawley rats. The results may provide evidence on underlying mechanisms of Mn-induced neurotoxicity, and aberrantly expressed lncRNAs/mRNAs may be useful in further investigations to detect early symptoms of Mn-induced neuropsychiatric disorders in the central nervous system.  相似文献   
3.
Jet-based technologies are increasingly being explored as potential high-throughput and high-resolution methods for the manipulation of biological materials. Previously shown to be of use in generating scaffolds from biocompatible materials, we were interested to explore the possibility of using electrospinning technology for the generation of scaffolds comprised of living cells. For this, it was necessary to identify appropriate parameters under which viable threads containing living cells could be produced. Here, we describe a method of electrospinning that can be used to deposit active biological threads and scaffolds. This has been achieved by use of a coaxial needle arrangement where a concentrated living biosuspension flows through the inner needle and a medical-grade poly(dimethylsiloxane) (PDMS) medium with high viscosity (12,500 mPa s) and low electrical conductivity (10-15 S m-1) flows through the outer needle. Using this technique, we have identified the operational conditions under which the finest cell-bearing composite microthreads are formed. Collected cells that have been cultured, postelectrospinning, have been viable and show no evidence of having incurred any cellular damage during the bionanofabrication process. This study demonstrates the feasibility of using coaxial electrospinning technology for biological and biomedical applications requiring the deposition of living cells as composite microthreads for forming active biological scaffolds.  相似文献   
4.
Mice with endothelial nitric oxide synthase (eNOS) deletions have defined the crucial role of eNOS in vascular development, homeostasis, and pathology. However, cell specific eNOS function has not been determined, although an important role of eNOS has been suggested in multiple cell types. Here, we have generated a floxed eNOS allele in which exons 9–12, encoding the sites essential to eNOS activity, are flanked with loxP sites. Mice homozygous for the floxed allele showed normal eNOS protein levels and no overt phenotype. Conversely, homozygous mice with Cre‐deleted alleles displayed truncated eNOS protein, lack of vascular NO production, and exhibited similar phenotype to eNOS knockout mice, including hypertension, low heart rate, and focal renal scarring. These findings demonstrate that the floxed allele is normal and it can be converted to a non‐functional eNOS allele through Cre recombination. This mouse will allow time‐ and cell‐specific eNOS deletion. genesis 50:685–692, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
5.
The open reading frame TM1080 from Thermotoga maritima encoding ribose-5-phosphate isomerase type B (RpiB) was cloned and over-expressed in Escherichia coli BL21 (DE3). After optimization of cell culture conditions, more than 30% of intracellular proteins were soluble recombinant RpiB. High-purity RpiB was obtained by heat pretreatment through its optimization in buffer choice, buffer pH, as well as temperature and duration of pretreatment. This enzyme had the maximum activity at 70°C and pH 6.5-8.0. Under its suboptimal conditions (60°C and pH 7.0), k(cat) and K(m) values were 540s(-1) and 7.6mM, respectively; it had a half lifetime of 71h, resulting in its turn-over number of more than 2×10(8)mol of product per mol of enzyme. This study suggests that it is highly feasible to discover thermostable enzymes from exploding genomic DNA database of extremophiles with the desired stability suitable for in vitro synthetic biology projects and produce high-purity thermoenzymes at very low costs.  相似文献   
6.
The objective of the present study was to assess the effect of alginate-encapsulated infectious pancreatic necrosis virus antigens in inducing the immune response of Atlantic salmon as booster vaccines. One year after intraperitoneal injection with an oil-adjuvanted vaccine, post-smolts were orally boosted either by 1) alginate-encapsulated IPNV antigens (ENCAP); 2) soluble antigens (UNENCAP) or 3) untreated feed (control). This was done twice, seven weeks apart. Sampling was done twice, firstly at 7 weeks post 1st oral boost and the 2nd, at 4 weeks after the 2nd oral boost. Samples included serum, head kidney, spleen and hindgut. Serum antibodies were analyzed by ELISA while tissues were used to assess the expression of IgM, IgT, CD4, GATA3, FOXP3, TGF-β and IL-10 genes by quantitative PCR. Compared to controls, fish fed with ENCAP had a significant increase (p<0.04) in serum antibodies following the 1st boost but not after the 2nd boost. This coincided with significant up-regulation of CD4 and GATA3 genes. In contrast, serum antibodies in the UNENCAP group decreased both after the 1st and 2nd oral boosts. This was associated with significant up-regulation of FOXP3, TGF-β and IL-10 genes. The expression of IgT was not induced in the hindgut after the 1st oral boost but was significantly up-regulated following the 2nd one. CD4 and GATA3 mRNA expressions exhibited a similar pattern to IgT in the hindgut. IgM mRNA expression on the other hand was not differentially regulated at any of the times examined. Our findings suggest that 1) Parenteral prime with oil-adjuvanted vaccines followed by oral boost with ENCAP results in augmentation of the systemic immune response; 2) Symmetrical prime and boost (mucosal) with ENCAP results in augmentation of mucosal immune response and 3) Symmetrical priming and boosting (mucosal) with soluble antigens results in the induction of systemic immune tolerance.  相似文献   
7.
X-linked ectodermal dysplasia receptor (XEDAR) is a recently isolated member of the tumor necrosis factor receptor family that has been shown to be highly expressed in ectodermal derivatives during embryonic development and binds to ectodysplasin-A2 (EDA-A2). By using a subclone of 293F cells with stable expression of XEDAR, we report that XEDAR activates the NF-kappaB and JNK pathways in an EDA-A2-dependent fashion. Treatment with EDA-A2 leads to the recruitment of TRAF3 and -6 to the aggregated XEDAR complex, suggesting a central role of these adaptors in the proximal aspect of XEDAR signaling. Whereas TRAF3 and -6, IKK1/IKKalpha, IKK2/IKKbeta, and NEMO/IKKgamma are involved in XEDAR-induced NF-kappaB activation, XEDAR-induced JNK activation seems to be mediated via a pathway dependent on TRAF3, TRAF6, and ASK1. Deletion and point mutagenesis studies delineate two distinct regions in the cytoplasmic domain of XEDAR, which are involved in binding to TRAF3 and -6, respectively, and play a major role in the activation of the NF-kappaB and JNK pathways. Taken together, our results establish a major role of TRAF3 and -6 in XEDAR signaling and in the process of ectodermal differentiation.  相似文献   
8.
Manifestations of myocardial infarctions have been recognized as one of the major killers in the Western world. Therefore, advancing and developing novel cardiac tissue repair and replacement therapeutics have great implications to our health sciences and well-being. There are several approaches for forming cardiac tissues, non-jet-based and jet-based methodologies. A unique advantage of jet-based approaches is the possibility to handle living cells with a matrix for cell distribution and deposition in suspension, either as single or heterogeneous cell populations. Our previous studies on bio-electrospraying of cardiac cells have shown great promise. Here, we show for the first time the ability to bio-electrospray the three major cell types of the myocardium, both independently and simultaneously, for forming a fully functional cardiac tissue. Several samples are characterized in vitro and found to be indistinguishable in comparison to controls. Thus, we are describing a swiftly emerging novel biotechnique for direct cardiac tissue generation. Moreover, the present investigations pave the way for the development and optimization of a bio-patterning approach for the fabrication of biologically viable cardiac tissue grafts for the potential treatment of severe heart failure after myocardial infarction.  相似文献   
9.
This study conducted experiments on three different downdraft gasification approaches: single stage, conventional two-stage, and an innovative two-stage air and premixed air/gas supply approach. The innovative two-stage approach has two nozzle locations, one for air supply at combustion zone and the other located at the pyrolysis zone for supplying the premixed gas (air and producer gas). The producer gas is partially bypassed to mix with air and supplied to burn at the pyrolysis zone. The result shows that producer gas quality generated by the innovative two-stage approach improved as compared to conventional two-stage. The higher heating value (HHV) increased from 5.4 to 6.5 MJ/Nm3. Tar content in producer gas reduced to less than 45 mg/Nm3. With this approach, gas can be fed directly to an internal combustion engine. Furthermore, the gasification thermal efficiency also improved by approximately 14%. The approach gave double benefits on gas qualities and energy savings.  相似文献   
10.
A luminous millipede. Luminodesmus sequoiae, emits light centered at a wavelength of 500 nm. To determine the light emitter of this bioluminescent system, fluorescent compounds were isolated from pulverized cuticles. NMR and MS spectra of these compounds showed them to be pterin derivatives. Furthermore, proton/deuterium (H/D) exchange experiments by ESI-Q-TOF-MS and -MS/MS measurements have proved to be a powerful tool for elucidating these heteroaromatic compounds. Finally, we have concluded that 7,8-dihydropterin-6-carboxylic acid, a new natural product, is the light emitter of Luminodesmus bioluminescence.  相似文献   
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