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Many studies have reported that G-protein β3 subunit (GNB3) C825T polymorphism is associated with essential hypertension (EH), although this remains subject to debate. Thus, meta-analysis was carried out to clarify this relationship. A total of 75 articles, reporting 81 case–control studies evaluating 28 369 patients and 34 933 control individuals, were assessed. Overall, a significant association was observed in the dominant model (odds ratio (OR)=1.11, 95% CI 1.04–1.19), recessive model (OR=1.09, 95% CI 1.01–1.17), TT vs CC (OR=1.16, 95% CI 1.05–1.28), CT vs CC (OR=1.09, 95% CI 1.02–1.17), and additive model (OR=1.07, 95% CI 1.02–1.13) after pooling all eligible studies. Subgroup analysis by ethnicity and gender demonstrated significantly increased EH only in Caucasians using the dominant (OR=1.22, 95% CI 1.07–1.39; TT vs CC, OR=1.29, 95% CI 1.07–1.54; CT vs CC, OR=1.19, 95% CI 1.05–1.35) and additive (OR=1.16, 95% CI 1.05–1.28) models. In summary, the present meta-analysis indicated the GNB3 C825Tpolymorphism is related to increased EH exclusively in Caucasians.

Despite of the common usage of glucocorticoids (GCs), a significant portion of asthma patients exhibit GC insensitivity. This could be mediated by diverse mechanisms, including genomics. Recent work has suggested that measuring changes in gene expression may provide more predictive information about GC insensitivity than baseline gene expression alone, and that expression changes in peripheral blood may be reflective of those in the airway.

Renal ischemia-reperfusion (I/R) is associated with activation of the coagulation system and accumulation of blood clotting factors in the kidney. The aim of the present study was to examine the functional impact of fibrinogen on renal inflammation, damage, and repair in the context of I/R injury. In this study, we found that I/R was associated with a significant increase in the renal deposition of circulating fibrinogen. In parallel, I/R stress induced the de novo expression of fibrinogen in tubular epithelial cells, as reflected by RT-PCR, immunofluorescence, and in situ hybridization. In vitro, fibrinogen expression was induced by oncostatin M and hyper-IL-6 in primary tubular epithelial cells, and fibrinogen-containing medium had an inhibitory effect on tubular epithelial cell adhesion and migration. Fibrinogen+/−mice showed similar survival as wild-type mice but better preservation in early postischemic renal function. In fibrinogen−/−mice, renal function and survival were significantly worse than in fibrinogen+/−mice. Renal transplant experiments revealed reduced expression of tubular damage markers and attenuated proinflammatory cytokine expression but increased inflammatory cell infiltrates and transforming growth factor-β expression in fibrinogen−/−isografts. These data point to heterogeneous effects of fibrinogen in renal I/R injury. While a complete lack of fibrinogen may be detrimental, partial reduction of fibrinogen in heterozygous mice can improve renal function and overall outcome.

Objective: It has been reported that impaired left ventricular longitudinal function may precede circumferential ventricular dysfunction in patients with coronary artery disease. This study is to determine the impact of PCI on myocardial function assessed by tissue Doppler echocardiography in patients with chronic stable angina. Method: Twenty-five consecutive patients with chronic stable angina and preserved systolic LV function (EF%> 50%) underwent PCI were studied by pulsed wave tissue Doppler at different time intervals before and after PCI. All patients were subjected to the following: Full history and physical examination, ECG, Echocardiography before PCI to evaluate baseline systolic & diastolic function as well as 1 day&6 weeks after intervention, and pulsed-wave tissue Doppler Echo was done before PCI, as well as 1 day&6 weeks after intervention to detect mitral and tricuspid inflow velocities, including E and A wave peak velocities (in centimeters per second). Result: We found that systolic myocardial peak velocities improved significantly after PCI in the septal, lateral, anterior, posterior, and inferior walls(P < 0.001 for each) by tissue Doppler imaging while non detected by conventional Echo. There was a significant increase of EA ratio at anterior angle of mitral valve annulus and lateral angle of tricuspid valve annulus.(p= 0.02 for both),also The right ventricle showed significant improvement in tissue Doppler measures of systolic function, early, and late diastolic function 1day &6 weeks after PCI compared with baseline values (P< .001),While non detected by conventional Echo. Conclusion: Tissue Doppler Echo. is a noninvasive and widely available diagnostic technique that allows the sensitive detection of right & left myocardial dysfunction.

Fractal theory and methodology were used to investigate the morphology of titanium–magnesium-supported polyethylene catalysts and their relevant polymer particles. Through an analysis of the submicrostructures using scanning electron microscopy images, the surface fractal dimensions of the related particles were estimated with the box-counting method. With consideration given to the fact that the growth process of a polymer is an evolving fractal process, which is controlled on the one hand by the initial conditions, including the initial fractal dimensions of the catalysts and the initial reaction conditions, and on the other hand by the previous morphology characteristics of the system, a novel polymerization fractal growth model was constructed. The simulation results showed good agreement with the experiment data. Moreover, the morphology evolution with the prepolymerization technique was predicted, and it was suggested that the duration of polymerization was 10–30 min. It was proven that the use of the surface fractal dimension as an important parameter describing the surface morphologies of the particles, either of catalysts or polymers, was real and effective. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1463–1470, 2003

Glutamate carboxypeptidase II (GCPII, NAALADase, or NAAG peptidase) is a catalytic zinc metallopeptidase. Its extracellular domain hydrolyzes the abundant neuropeptide, N-acetyl-l-aspartyl-l-glutamate (NAAG), to produce N-acetylaspartate and glutamate following the synaptic release of this transmitter. Thus, GCPII influences the extracellular concentrations of both glutamate and NAAG. NAAG activates group II metabotropic glutamate receptors, and activation of this receptor has been found to protect against anoxia-induced excitotoxic nerve cell death. In contrast, high levels of glutamate can be neurotoxic. Thus, GCPII is a potential therapeutic target for the reduction of excitotoxic levels of glutamate and enhancement of extracellular NAAG. To explore the structural basis of the interaction between GCPII and its inhibitors, we modeled the three-dimensional structure of the GCPII extracellular domain using a homology modeling approach. On the basis of the GCPII model, the structures of GCPII in complex with its potent inhibitors 2-(phosphonomethyl)pentanedioic acid (PMPA) and 4,4‘-phosphinicobis(butane-1,3-dicarboxylic acid) (PBDA) were built by a computational docking method. The model of GCPII mainly consists of two α/β/α sandwiches, between which two zinc ions are quadrivalently coordinated by the His379-Asp389-Asp455-H2O and the Asp389-Glu427-His555-H2O clusters, respectively. The ligand binding pocket is situated between these two sandwiches and is comprised of two subpockets:  one is a surface-exposed highly positively charged subpocket; the other is a buried hydrophobic subpocket. The positively charged subpocket can accommodate the pharmacophore groups of inhibitor molecules (PMPA and PBDA) through the coordination of Zn²⁺ with their phosphorus functionality and hydrogen-bonding interactions with Arg536, Arg538, and Ser456 (or Asn521), while the hydrophobic subpocket is engaged in hydrophobic and hydrogen-bonding interactions with the nonpharmacophore groups of PBDA. The predicted binding mode is consistent with the experimental data obtained from site-directed mutagenesis. On the basis of the predicted interaction mode, our structure-based design has led to a series of highly potent GCPII inhibitors.

The so-called condensed mode operation is more fashionable at present in the gas-phase fluidized-bed ethylene polymerization process because of a substantial increase in the space-time yield of polymer production. However, the instability of the fluidized bed in condensed mode operation has never been analyzed theoretically before regardless of its critical importance of commerce. The mechanism of “wet state instability” was first proposed in this paper for the instability analysis due to agglomeration of fluidizing particles. The absorption of heavy components on the polymer particles was assumed to make particles stickier by formation of a liquid bridge. On the basis of a force balance of the agglomerate, a novel model has been developed to predict the maximal mole fraction of the condensed agent (isopentane) permissively existing in the fluidizing gas stream and then to distinguish the unstable operating zone of the fluidized bed. It is found that the theoretical calculation agrees with the industrial operation data very well. Moreover, a criterion was recommended to identify the transition of polymer powders from group B, through A, to group C, in which the bed layer would be collapsed because of the excessive cohesive forces acting among the particles.

The Ras guanyl releasing protein RasGRP belongs to the CDC25 class of guanyl nucleotide exchange factors that regulate Ras-related GTPases. These GTPases serve as switches for the propagation and divergence of signaling pathways. One interesting feature of RasGRP is the presence of a C-terminal C1 domain, which has high homology to the PKC C1 domain and binds to diacylglycerol (DAG) and phorbol esters. RasGRP thus represents a novel, non-kinase phorbol ester receptor. In this paper, we investigate the binding of indolactam(V) (ILV), 7-(n-octyl)-ILV, 8-(1-decynyl)benzolactam(V) (benzolactam), and 7-methoxy-8-(1-decynyl)benzolactam(V) (methoxylated benzolactam) to RasGRP through both experimental binding assays and molecular modeling studies. The binding affinities of these lactams to RasGRP are within the nanomolar range. Homology modeling was used to model the structure of the RasGRP C1 domain (C1-RasGRP), which was subsequently used to model the structures of C1-RasGRP in complex with these ligands and phorbol 13-acetate using a computational docking method. The structural model of C1-RasGRP exhibits a folding pattern that is nearly identical to that of C1b-PKCδ and is comprised of three antiparallel-strand β-sheets capped against a C-terminal α-helix. Two loops A and B comprising residues 8−12 and 21−27 form a binding pocket that has some positive charge character. The ligands phorbol 13-acetate, benzolactam, and ILV are recognized by C1-RasGRP through a number of hydrogen bonds with loops A and B. In the models of C1-RasGRP in complex with phorbol 13-acetate, benzolactam, and ILV, common hydrogen bonds are formed with two residues Thr12 and Leu21, whereas other hydrogen bond interactions are unique for each ligand. Furthermore, our modeling results suggest that the shallower insertion of ligands into the binding pocket of C1-RasGRP compared to C1b-PKCδ may be due to the presence of Phe rather than Leu at position 20 in C1-RasGRP. Taken together, our experimental and modeling studies provide us with a better understanding of the structural basis of the binding of PKC ligands to the novel phorbol ester receptor RasGRP.

The serine−threonine protein kinase Akt is a direct downstream target of phosphatidylinositol 3-kinase (PI3-K). The PI3-K-generated phospholipids regulate Akt activity via directly binding to the Akt PH domain. The binding of PI3-K-generated phospholipids is critical to the relocalization of Akt to the plasma membrane, which plays an important role in the process of Akt activation. Activation of the PI3-K/Akt signaling pathway promotes cell survival. To elucidate the structural basis of the interaction of PI3-K-generated phospholipids with the Akt PH domain with the objective of carrying out structure-based drug design, we modeled the three-dimensional structure of the Akt PH domain. Comparative modeling-based methods were employed, and the modeled Akt structure was used in turn to construct structural models of Akt in complex with selected PI3-K-generated phospholipids using the computational docking approach. The model of the Akt PH domain consists of seven β-strands forming two antiparallel β-sheets capped by a C-terminal α-helix. The β1−β2, β3−β4, and β6−β7 loops form a positively charged pocket that can accommodate the PI3-K-generated phospholipids in a complementary fashion through specific hydrogen-bonding interactions. The residues Lys14, Arg25, Tyr38, Arg48, and Arg86 form the bottom of the binding pocket and specifically interact with the 3- and 4-phophate groups of the phospholipids, while residues Thr21 and Arg23 are situated at the wall of the binding pocket and bind to the 1-phosphate group. The predicted binding mode is consistent with known site-directed mutagenesis data, which reveal that mutation of these crucial residues leads to the loss of Akt activity. Moreover, our model can be used to predict the binding affinity of PI3-K-generated phospholipids and rationalize the specificity of the Akt PH domain for PI(3,4)P2, as opposed to other phospholipids such as PI(3)P and PI(3,4,5)P3. Taken together, our modeling studies provide an improved understanding of the molecular interactions present between the Akt PH domain and the PI3-K-generated phospholipids, thereby providing a solid structural basis for the design of novel, high-affinity ligands useful in modulating the activity of Akt.

Phosphatidylinositol 3-kinase (PI3-K) phosphorylates the 3-position of phosphatidylinositol to give rise to three signaling phospholipids. Binding of the pleckstrin homolgy (PH) domain of Akt to membrane PI(3)P's causes the translocation of Akt to the plasma membrane bringing it into contact with membrane-bound Akt kinase (PDK1 and 2), which phosphorylates and activates Akt. Akt inhibits apoptosis by phosphorylating Bad, thus promoting its binding to and blockade of the activity of the cell survival factor Bcl-x. Herein we present the synthesis and biological activity of several novel phosphatidylinositol analogues and demonstrate the ability of the carbonate group to function as a surrogate for the phosphate moiety. Due to a combination of their PI3-K and Akt inhibitory activities, the PI analogues 2, 3, and 5 proved to be good inhibitors of the growth of various cancer cell lines with IC50 values in the 1−10 μM range. The enhanced Akt inhibitory activity of the axial hydroxymethyl-bearing analogue 5 compared to its equatorial counterpart 6 is rationalized based upon postulated differences in the H-bonding patterns of these compounds in complex with a homology modeling generated structure of the PH domain of Akt. This work represents the first attempt to examine the effects of 3-modified PI analogues on these two crucial cell signaling proteins, PI3-K and Akt, in an effort to better understand their cell growth inhibitory properties.

Transcription from some sporulation-specific promoters of Bacillus subtilis is dependent on synthesis of pro-sigma E and its conversion to sigma E by proteolysis. Certain mutations in the precursor region of sigE, the gene encoding pro-sigma E, apparently allow the mutant sigE products to be active as sigma factors without being proteolysed in the normal way.

Hepatocyte growth factor/scatter factor (HGF/SF) is a pleiotropic effector of cells expressing the Met tyrosine kinase receptor. Although HGF/SF is synthesized by mesenchymal cells and acts predominantly on epithelial cells, we have recently demonstrated that human sarcoma cell lines often inappropriately express high levels of Met and respond mitogenically to HGF/SF. In the present report we show that HGF/SF-Met signalling in the human leiomyosarcoma cell line SK-LMS-1 enhances its in vivo tumorigenicity, an effect for which the mitogenicity of this signalling pathway is likely to play a role. In addition, we found that HGF/SF-Met signalling dramatically induces the in vitro invasiveness and in vivo metastatic potential of these cells. We have studied the molecular basis by which HGFSF-Met signalling mediates the invasive phenotype. A strong correlation has previously been demonstrated between the activation of the urokinase plasminogen activator (uPA) proteolysis network and the acquisition of the invasive-metastatic phenotype, and we show here that HGF/SF-Met signalling significantly increases the protein levels of both uPA and its cellular receptor in SK-LMS-1 cells. This results in elevated levels of cell-associated uPA and enhanced plasmin-generating ability by these cells. These studies couple HGF/SF-Met signalling to the activation of proteases that mediate dissolution of the extracellular matrix-basement membrane, and important property for cellular invasion-metastasis.

The spoIIIC locus of Bacillus subtilis has been cloned from the lambda library of Ferrari et al. (E. Ferrari, D. J. HEnner, and J. A. Hoch, J. Bacteriol. 146:430-432, 1981) by using as an assay transformation of the mutant allele spoIIIC94 to the wild type. Regulation of the spoIIIC locus was studied by hybridization of cloned spoIIIC DNA to RNA pulse-labeled at various times during growth and sporulation. The relative rate of transcription of the spoIIIC locus was highest 3 h after the end of growth. The DNA sequence of the spoIIIC transcription unit indicated the coding capacity for a small protein (138 amino acids) having significant similarity with one domain of RNA polymerase sigma factors. Interruption of this coding sequence by an insertion mutation caused cells to become Spo-.

The met protooncogene product, Met, is the tyrosine kinase growth factor receptor for hepatocyte growth factor/scatter factor (HGF/SF). NIH 3T3 cells express HGF/SF endogenously and become tumorigenic in nude mice via an autocrine mechanism when murine Met is expressed ectopically (Metmu cells) or when human Met and human HGF/SF are coexpressed (HMH cells). Here, we show that Metmu and HMH cells are invasive in vitro and display enhanced protease activity necessary for the invasive phenotype. In experimental and spontaneous metastasis assays, Metmu or HMH cells metastasize to the lung, but lower numbers of subcutaneously injected Metmu and HMH cells produced invasive tumors in the heart, diaphragm, salivary gland, and retroperitoneum. It has been reported elsewhere that Met expression increased with tumor passage in athymic nude mice, and these tumor explants show enhanced activity in the metastasis assays. Autocrine-mediated Met-HGF/SF signal transduction in NIH 3T3 mesenchymal cells may provide an important system for understanding the biological process of metastasis.

The met proto-oncogene is the tyrosine kinase growth factor receptor for hepatocyte growth factor/scatter factor (HGF/SF). It was previously shown that, like the oncogenic tpr-met, the mouse met proto-oncogene transforms NIH 3T3 cells. We have established NIH 3T3 cells stably expressing both human (Methu) and mouse (Metmu) met proto-oncogene products. The protein products are properly processed and appear on the cell surface. NIH 3T3 cells express endogenous mouse HGF/SF mRNA, suggesting an autocrine activation mechanism for transformation by Metmu. However, the tumor-forming activity of Methu in NIH 3T3 cells is very low compared with that of Metmu, but efficient tumorigenesis occurs when Methu and HGF/SFhu are coexpressed. These results are consistent with an autocrine transformation mechanism and suggest further that the endogenous murine factor inefficiently activates the tumorigenic potential of Methu. The tumorigenicity observed with reciprocal chimeric human and mouse receptors that exchange external ligand-binding domains supports this conclusion. We also show that HGF/SFhu expressed in NIH 3T3 cells produces tumors in nude mice.

We cloned the wild-type allele of the spoIID locus of Bacillus subtilis. This DNA region was shown to be transcribed beginning within an hour after the onset of sporulation. The amount of spoIID mRNA present in cells at 1 h after the end of growth was more than 50-fold greater than it was growing cells; the pool of this mRNA decreased steadily after 1.5 h after the end of growth. spoIID mRNA was present in stationary-phase cells of sporulation mutants with lesions in the spo0J and spoIIB genes but was absent in cells carrying spo0B, spo0H, spoIIA, spoIIE, spoIIG, or spoIIIA mutations. In vitro runoff transcription with the E sigma 55, E sigma 37, E sigma 32, and E sigma 29 forms of RNA polymerase indicated that only the E sigma 29 form was able to transcribe the spoIID gene. This result is consistent with results of studies with the Spo- mutants, because only mutants that produced E sigma 29 were able to produce spoIID mRNA in vivo. In the course of this work, two additional transcription units were discovered in the DNA region neighboring the spoIID gene. One of these was expressed during vegetative growth; the other was expressed early during sporulation and corresponded to an in vitro transcript produced by the E sigma 29 forms of RNA polymerase.

The liquid-solid composite technique was used to prepare the high carbon high chromium steel (HCHCS) and low alloy steel (LCS) bimetal composite materials by means of insert casting method. The influence of some process parameters such as liquid-solid ratio, preheat temperature, pouring temperature on the interface microstructure and mechanical properties were studied. Interface microstructure and element distribution were analyzed. The results show that the interface microstructure becomes better, and bonding area becomes thicker with the increase of the volume of liquid to solid ratio, preheating temperature and pouring temperature. When the liquid-solid ratio is 8:1, the preheating temperature is 300 degC and the pouring temperature is 1565 degC, a good metallurgical bonding area without any hole can be obtained with the interface combination of diffusion and fusion. The composite interface structure was composed of a core material diffusion layer, a cooling solidification layer, a direction growth layer and some cell particles. The elements of C, Cr and Mn diffuse from the HCHCS side to the alloy steel side. The microhardness increased in the gradient from the LCS side to the HCHCS. The microhardness of the interface is significantly higher than that of LCS.