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1.
ERRATUM     
Equation (2) should read: Equation (5) should read:   相似文献   

2.
ERRATUM     
Equation (2) should read: Equation (5) should read:   相似文献   

3.
Equation 14 on p. 68 should read: Equation 20 on p. 69 should read:   相似文献   

4.
On page 526 of this article, equations (4), (5), and (7) should be corrected as follows. Equation (4) should read: Equation (5) should read: Equation (7) should read: The authors acknowledge the useful comments made by Dr. Enda Crossin and Sean Frost from the Centre for Design, RMIT University, Melbourne, Australia.  相似文献   

5.
Summary An idea is proposed for the role of the circadian rhythmicity in the control of the oscillatory behavior observed in the growth and product formation during the cell-retention continuous culture of Clostridium acetobutylicum. C. acetobutylicum is highly sensitive to the permeability of the cell membrane. A physical mechanism for the variability of the cytoplasmic membrane has been proposed suggesting that the performance of the cell membrane, due to its liquid crystalline structure, is influenced by the external forces (e.g. earth's magnetic field). A previously developed Physiological State Model was extended by incorporating the effect of external forces on the cell membrane permeability. The new mathematical model could simulate the observed oscillatory behavior of the microbial culture. Some experimental results in support of the theoretical predictions have been presented.Nomenclature a Anisotropy - B Butanol concentration in the fermentation broth (g/l) - B i Intracellular butanol concentration (g/l) - B ex Extracellular butanol concentration (g/l) - Mean value of the butyric acid solution concentration (g/l) - BA i Intracellular butyric acid concentration (g/l) - BA ex Extracellular butyric acid concentration (g/l) - D Dilution rate (l/h) - H Magnetizing force (oersted) - K Constant in Equation (1) - k B Constant in Equation (15) - K BA Saturation constant - k BA 1 Constant in Equation (13) - k BA 2 Constant in Equation (13) - K D Constant in Equation (13) - k G 1 Constant in Equation (8) - k G 2 Constant in Equation (8) - k G 3 Constant in Equation (9) - K I Inhibition Constant - k p Constant in Eq. (11) - K S Monod constant - n Number of the active sugar transport sites - P Cellular membrane permeability (l/g wet cell·h) - q S Specific rate of substrate utilization (g substrate/g biomass·h) - S Substrate concentration in the fermentation broth (g/l) - S O Substrate concentration in the feed solution (g/l) - t Time (h) - X Total biomass concentration (g/l) - X 1 Active biomass concentration (g/l) - X 2 Non-active biomass concentration (g/l) Greek Letters Ratio of the dry to wet cell weight (g dry cell/g wet cell) - 1 Constant in Equation (6) - 2 Constant in Equation (6) - 3 Constant in Equation (6) - Specific culture growth rate (1/h)  相似文献   

6.
ERRATA     
Errata is paper by Swanson and Whitfield, Vol. 32(126), 221–239. Equation (6), page 223. should read: Page 231; 7th line in first paragraph Fig. 7, vice Fig. 8 Page 237; Figure 12 caption, end of third line K = 0.46 vice K = 0.16  相似文献   

7.
8.

Background

Aberrant expression of B7 homologue 3 (B7H3) has been observed in various malignancies. Our previous study demonstrated that knocking down of B7H3 inhibited cell proliferation, invasion and enhanced the therapeutic efficacy of chemotherapy in mantle cell lymphoma (MCL). However, the mechanism regulating of B7H3 expression remains unknown. Here, we present a new regulatory microRNA of B7H3, miR-506, that directly targets B7H3 and may play an inhibitory role in MCL progression.

Methods

The expression of miR-506 and B7H3 was investigated by real-time quantitative PCR (RT-qPCR). B7H3 was confirmed to be a novel direct target gene of miR-506 by a dual-luciferase assay and western blot analysis. MiR-506 overexpression in the Maver and Z138 MCL cell lines was established using lentiviral transduction. Cell counting kit-8, flow cytometry and Transwell assays were used to detect changes in cell proliferation, cycle distribution, migration and invasion, respectively.

Results

The RT-qPCR results showed that miR-506 was expressed at a low level, while B7H3 was overexpressed in MCL patients and cell lines. By using a bioinformatics analysis combined with a dual-luciferase assay, we determined that miR-506 could target the 3‘-untranslated region (3′-UTR) of B7H3 mRNA. Moreover, miR-506 had a negative regulatory effect on B7H3 expression according to the western blotting and RT-qPCR results. In terms of function, increased expression of miR-506 led to reduced MCL cell proliferation, invasion and migration, caused cell cycle arrested at G0/G1 phase, similar to the effects of B7H3 knockdown. Furthermore, we measured the expression of invasion-related proteins by western blotting and found that miR-506 could reduce MMP-2 and MMP-9 expression in MCL cells. Rescue experiments suggested that the restoration of B7H3 expression in MCL cells reversed the inhibition of proliferation and invasion induced by miRNA-506 overexpression.

Conclusions

Our findings suggest that miR-506 functions as a tumor suppressor miRNA and plays a significant role in inhibiting human MCL cell proliferation and metastasis by suppressing B7H3 expression.  相似文献   

9.
A cone disk atomizer has been designed for preparation of gelatin/polystyrene magnetic microcapsules for use as microcarriers in anchorage-dependent mammalian cell culture. This apparatus facilitates continuous production of microcapsules and ignores surfactants or organic solvents in traditional emulsion. Compared with the flat-disk atomizer, the feeding flow is subjected to a normal pressure provided by the special cone-shaped disk and liquid slide is dramatically decreased in the cone-disk atomizer. A flow-rate-limitation is observed in both flat-disk atomization and cone-disk atomization. A 36% increase in flow-rate limitation was observed in cone-disk atomization than in flat-disk atomization indicating the potential of this method for large-scale preparations. Nomenclature d p average diameter of solid cores (m)D disk diameter (m)g gravity acceleration (9.8 m s–2) Ga Galileo number defined by Equation (3) Q flow rate of feeding slurry (m3 s–1) Re Q flow rate Reynolds number defined by Equation (2)Re rotating speed Reynolds number defined by Equation (1) angular speed of rotating disk (rad s–1) l density of liquid (kg m–3) s density of the mixing slurry (kg m–3) density difference between solid cores and liquid (kg m–3) viscosity of the mixing slurry (Pa s)  相似文献   

10.
Petroselinic acid (18:16) is the major component of the seed oil of Umbelliferae species such as coriander (Coriandrum sativum) as well as Araliaceae and Garryaceae species. This unusual fatty acid is synthesized in plastids by the 4 desaturation of palmitoyl-acyl carrier protein (16:0-ACP) and subsequent elongation of 4-hexadecenoyl (16:14)-ACP. To characterize the enzymatic nature of the elongation reaction, an in vitro assay was developed with 16:14-ACP and 16:0-ACP as substrates. Extracts from developing coriander seeds elongated 16:14-ACP in a competitive assay at rates ten-fold greater than that with 16:0-ACP. In contrast, extracts from castor seeds, which do not synthesize petroselinic acid, displayed a strong preference for the elongation of 16:0-ACP rather than 16:14-ACP. In addition, the elongation of 16:14-ACP and 16:0-ACP by coriander seed extracts was strongly inhibited by cerulenin at concentrations as low as 10 M. This finding suggested that the elongation of 16:14-ACP and 16:0-ACP in coriander seed is catalyzed by a 3-ketoacyl-ACP synthase (KAS) I-type enzyme(s), rather than a KAS II-type activity that is typically associated with 16:0-ACP elongation. Consistent with this, a cDNA for a diverged form of KAS I was isolated from a cDNA library prepared from developing coriander seed. Using a variety of heterologous probing techniques, no KAS II-type cDNAs could be identified in this library. Multiple alignment of KAS amino acid sequences indicated that, although the polypeptide corresponding to the coriander cDNA is more closely related to KAS I, its active site motif deviates from those found in both KAS I and KAS II enzymes. Also suggestive of a possible role in petroselinic acid synthesis, antibodies raised to the recombinant protein recognize an abundant 45 kDa polypeptide in coriander endosperm that is not detected in coriander leaves. These antibodies also recognize a major band of similar size in developing seeds of English ivy (Hedera helix), an Araliaceae species that also accumulates petroselinic acid in a seed-specific manner.  相似文献   

11.
Release of reactive oxygen species (ROS), measured as the sum of hydrogen peroxide (H2O2) and superoxide anion radical (), from respiring rat heart and skeletal muscle mitochondria was significantly decreased by millimolar concentrations of GTP or GDP. Attempts to differentiate between the two forms of ROS showed that the release of rather than that of H2O2 was affected. Meanwhile, intramitochondrial ROS accumulation, measured by inactivation of aconitase, increased. These results suggest that guanine nucleotides inhibit the release of from mitochondria. As these nucleotides are known inhibitors of uncoupling proteins (UCPs), it is proposed that UCPs may function as carriers of , thus enabling its removal from the matrix compartment.  相似文献   

12.
Summary The recent models of the Acetone-Butanol fermentation did not adequately describe the culture inhibition by the accumulating metabolites and were unable to simulate the acidogenic culture dynamics at elevated pH levels. The present updated modification of the model features a generalised inhibition term and a pH dependent terms for intracellular conversion of undissociated acids into solvent products. The culture dynamics predictions by the developed model compared well with experimental results from an unconventional acidogenic fermentation ofC. acetobutylicum.Nomenclature A acetone concentration in the fermentation broth, [g/L] - AA total concentration of dissociated and undissociated acetic acid, [g/L] - AA undiss concentration of undissociated acetic acid, [g/L] - APS Absolute Parameter Sensitivity - AT acetoin concentration in the fermentation broth, [g/L] - B butanol concentration in the fermentation broth, [g/L] - BA total concentration of dissociated and undissociated butyric acid, [g/L] - BA undiss concentration of undissociated butyric acid, [g/L] - E ethanol concentration in the fermentation broth, [g/L] - f(T) inhibition function as defined in Equation (2) - k 1 constant in Equation (4), [g substrate/g biomass] - k 2 constant in Equation (4), [g substrate/(g biomass.h)] - k 1 constant in Equation (5), [g substrate/(g biomass] - k 2 constant in Equation (5), [g substrate/(g biomass.h)] - k 3 constant in Equation (6), [g butyric acid/g substrate] - k 4 constant in Equation (6), [g butyric acid/(g biomass.h)] - k 5 constant in Equation (7), [g butanol/g substrate] - k 6 constant in Equation (8), [g acetic acid/g substrate] - k 7 constant in Equation (8), [g acetic acid/(g biomass.h)] - k 8 constant in Equation (9), [g acetone/g substrate] - k 9 constant in Equation (10), [g ethanol/g substrate] - k 10 constant in Equation (11), [g acetoin/g substrate] - k 11 constant in Equation (12), [g lactic acid/g substrate] - K I Inhibition constant, [g inhibitory products/L] - ke maintenance energy requirement for the cell, [g substrate/(g biomass.h)] - K AA acetic acid saturation constant, [g acetic acid/L] - K BA butyric acid saturation constant, [g butyric acid/L] - K S Monod's saturation constant, [g substrate/L] - LA lactic acid concentration in the fermentation broth, [g/L] - m i ,n i constants in Equation (14) - n empirical constant, dependent on degree of inhibition. - P concentration of inhibitory products (B+BA+AA), [g/L] - P max maximum value of product concentration to inhibit the fermentation, [g/L] - pKa equilibrium constant - r A rate of acetone production, [g acetone/L.h] - r AA rate of acetic acid production, [g acetic acid/L.h] - r AT rate of acetoin production, [g acetoin/L.h] - r B rate of butanol production, [g butanol/L.h] - r BA rate of butyric acid production, [g butyric acid/L.h] - r E rate of ethanol production, [g ethanol/L.h] - RPS Relative Parameter Sensitivity - r LA rate of lactic acid production, [g lactic acid/L.h] - r S dS/dt=total substrate consumption rate, [g substrate/L.h] - r S substrate utilization rate, [g substrate/L.h] - S substrate concentration in the fermentation broth, [g substrate/L] - S 0 initial substrate concentration, [substrate/L] - t time, [h] - X biomass concentration, [g/L] - Y X yield of biomass with respect to substrate, [g biomass/g substrate] - Y P i yield of metabolic product with respect to substrate, [g product/g substrate] Derivatives dX/dt rate of biomass production, [g biomass/L.h] - dP i /dt rate of product formation, [g product/L.h] Greek letters specific growth rate of the culture, [h–1] - I specific growth rate of the culture in the presence of the inhibitory products, [h–1] - µmax maximum specific growth rate of the culture, [h–1]  相似文献   

13.
Pirfenidone (PFD) is focused on a new anti-fibrotic drug, which can minimize lung fibrosis etc. We evaluated the superoxide () scavenging activities of PFD and the PFD-iron complex by electron spin resonance (ESR) spectroscopy, luminol-dependent chemiluminescence assay, and cytochrome c reduction assay. Firstly, we confirmed that the PFD-iron complex was formed by mixing iron chloride with threefold molar PFD, and the complex was stable in distillated water and ethanol. Secondary, the PFD-iron complex reduced the amount of produced by xanthine oxidase/hypoxanthine without inhibiting the enzyme activity. Thirdly, it also reduced the amount of released from phorbor ester-stimulated human neutrophils. PFD alone showed few such effects. These results suggest the possibility that the scavenging effect of the PFD-iron complex contributes to the anti-fibrotic action of PFD used for treating idiopathic pulmonary fibrosis.  相似文献   

14.
Summary The passive electrical properties and initiation of action potentials have been examined in the external epithelium of oikopleurid larvacean tunicates. The epithelial cells are electrically coupled, and are polygons up to 200 m across and up to 1.4–2.8 m thick. Membrane constants determined by a 2-electrode study were forO. dioica:: 922 m; Rm: 4.3 kcm2; Ri: 82.7 cm. Corresponding values for the largerO. longicauda were: 3350 m; 35.6 kcm2; and 104.5 cm. Mean resting potentials in both species were around 80 mV. Mechanical stimulation evokes over-shooting action potentials propagated (at 18 °C) at some 40 cm/s. These are rapid events, repolarisation being almost complete in 5 ms. There is no undershoot.When the recording electrode penetrates the epithelial cell from its inner surface distant mechanical stimulation may evoke similar action potentials arising from the stimulus site, but more often evokes graded small depolarisations which give rise to action potentials with increasing strength of mechanical stimulation. Reasons are given for considering these to be generator potentials resulting from deformation of the outer epithelial cell membrane by the tip of the recording electrode. The effects of epithelial action potentials upon the potentials recorded from the caudal muscle cells are briefly described.  相似文献   

15.
Communities of marine phytoplankton consist of cells of many different sizes. The size-structure of these communities often varies predictably with environmental conditions in aquatic systems. It has been hypothesized that physiological differences in nutrient and light requirements and acquisition efficiencies contribute to commonly observed correlations between phytoplankton community size structure and resource availability. Using physiological models we assess how light and nutrient availability can alter the relative growth rates of phytoplankton species of different cell sizes. Our models predict a change in the size dependence of growth rate depending on the severity of limitation by light and nutrient availability. Under conditions of growth-saturated resource supply, phytoplankton growth rate (mol C ) scales with cell volume with a size-scaling exponent of ; light limitation reduces the size-scaling exponent to approximately , and nutrient limitation decreases the exponent to as a consequence of the size-scaling of resource acquisition. Exponents intermediate between and occur under intermediate availability of light and nutrients and depend on the size-scaling of pigment photoacclimation and the size range examined.  相似文献   

16.
The effect of growth temperature on the compositions of phospholipidsand fatty acids of the psychrotrophic bacterium Pseudomonassp. strain E-3 was studied. The composition of phospholipids(phosphatidylethanolamine, phosphatidylglycerol and cardiolipin)did not differ significantly in cells grown at 5?, 15?, and30?C. Phosphatidylethanolamine (PE) was the most abundant, amountingto over 70% of total phospholipids. When the growth temperaturewas lowered, palmitoleic [16:1(9)] and cis-vaccenic [18:1(11)]acids increased at the expense of palmitic (16:0) acid, especiallyin PE. In vivo experiments using [l-14C]16:0 showed that incorporationof radioactivity into 16:1(9) was oxygen-dependent and cerulenin-insensitive,and incorporation into 18:1(11) was cerulenin-sensitive. Theseresults suggest that 16:0 was aerobically desaturated to 16:1(9)and subsequently elongated to 18:1(11). Desaturation activityof 16:0 in the cells grown at 25?C was enhanced by loweringthe assay temperature. (Received February 12, 1987; Accepted July 10, 1987)  相似文献   

17.
Human α-globin maps to pter-p13.3 in chromosome 16 distal to PGP   总被引:11,自引:0,他引:11  
Summary Fibroblasts from a fetus with an unbalanced karyotype 46(XY),-16,+(16qter-16p13.3::4q31.1-4qter) were found to possess only one allele at the 3 hypervariable region (3HVR) close to the -globin locus and two alleles at the PGP locus. This places the -globin locus at the very tip of 16p, distal to PGP.  相似文献   

18.
The crystal and molecular structure of the fluorescent probe 8-anilino-1-naphthalenesulfonic acid (ANS) has been determined as the ammonium monohydrate with two conformationally distinct molecules in the triclinic P1¯ lattice. The angles between the aromatic rings and the CNC plane are ?9/22° and 112/22° respectively. There is an NH...O intramolecular hydrogen bond in each molecule indicating that hydrogen bond formation is not dependent on the anilino geometry. There are also short intramolecular H...H contacts involving the hydrogens which have anomalous proton shifts shown in a recent NMR study.  相似文献   

19.
Immune responses against antigens generally require an efficient activation of antigen-presenting cells (APCs). Currently, the targeting of vaccine antigens to APCs has emerged as a promising strategy for boosting vaccine immunogenicity. Here, we reported that the C-terminus of heat shock protein 60 (HSP60C) can activate mouse peritoneal macrophages to secret a series of cytokines, and phosphorylation of p38 mitogen-activated protein kinase (MAPK) and NF-κB p65 was involved in the pathway. We showed that the activation effect of HSP60C on macrophages was independent of toll-like receptor (TLR) 4 and the TLR-associated myeloide differentiation factor 88 (MyD88). Knockdown of lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) reduced the activation of HSP60C-induced macrophage p38 MAPK, NF-κB p65 and cytokine secretion to some extent. Finally, we found that HSP60C up-regulated the expression of LOX-1 on macrophages and ovalbumin (OVA) model antigen fused with HSP60C markedly enhanced OVA-specific IgG responses. Thus, our results unravel a novel LOX-1-dependent pathway by which HSP60C can effectively activate macrophages and APCs targeting based on LOX-1 interaction is a promising approach to improve vaccines.  相似文献   

20.
A model of the dissolution kinetics of powdered enamel is developed based on the kinetic rate termq,
$$q = K'H - k'C \cdot P_1$$  相似文献   

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