Lack of association between α2-macroglobulin polymorphisms and Alzheimer's disease

This study was undertaken to investigate the role of two alpha2-macroglobulin (A2M) polymorphisms, an intronic 5-bp deletion and Ile1000Val, in the development of Alzheimer's disease (AD) and to evaluate the interaction between the apolipoprotein E (APOE) and A2M polymorphisms. The A2M polymorphisms were screened by using polymerase-chain-reaction-based assays in 555 white late-onset AD cases and 446 controls. The gentoype distributions of the 5-bp deletion and Ile1000Val polymorphisms were comparable between cases and controls (P = 0.158 and P = 0.148, respectively). Likewise, there was no significant difference in allele frequencies of each polymorphism among cases and controls (P = 0.361 and P = 0.062, respectively). The stratification of data by APOE*4 status also did not yield any significant association. In conclusion, we observed no association between either the intronic deletion polymorphism or the Ile1000Val polymorphism of A2M and AD in our case-control cohort.     

Duplication of insertion element IS50 associated with Tn5 transposition in Azospirillum brasilense

The characterization of a DNA fragment with a Tn5 insertion in a regulatory nif gene of Azospirillum brasilense is reported. Restriction endonuclease mapping, Southern hybridization with a Tn5 probe, and nucleotide sequencing revealed that IS50 had duplicated in Tn5. The duplication of an IS50 element suggests the occurrence of a replicative mechanism of transposition. A strategy, based on the bacterial ability of homologous recombination that was used to precisely eliminate Tn5 along with the duplicated IS50 element, is presented.     

High-resolution separation of tubulin monomers on polyacrylamide minigels

High-resolution separation of α- and β-tubulin by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) on minigels can be performed rapidly using simple modifications of the standard Laemmli procedure. Separation of the subunits can be observed even in high-protein loads (up to 40 μg of protein).     

Blood pressure regulation in neurally intact human vs. acutely injured paraplegic and tetraplegic patients during passive tilt

We investigated autonomic control of cardiovascular function in able-bodied (AB), paraplegic (PARA), and tetraplegic (TETRA) subjects in response to head-up tilt following spinal cord injury. We evaluated spectral power of blood pressure (BP), baroreflex sensitivity (BRS), baroreflex effectiveness index (BEI), occurrence of systolic blood pressure (SBP) ramps, baroreflex sequences, and cross-correlation of SBP with heart rate (HR) in low (0.04-0.15 Hz)- and high (0.15-0.4 Hz)-frequency regions. During tilt, AB and PARA effectively regulated BP and HR, but TETRA did not. The numbers of SBP ramps and percentages of heartbeats involved in SBP ramps and baroreflex sequences increased in AB, were unchanged in PARA, and declined in TETRA. BRS was lowest in PARA and declined with tilt in all groups. BEI was greatest in AB and declined with tilt in all groups. Low-frequency power of BP and the peak of the SBP/HR cross-correlation magnitude were greatest in AB, increased during tilt in AB, remained unchanged in PARA, and declined in TETRA. The peak cross-correlation magnitude in HF decreased with tilt in all groups. Our data indicate that spinal cord injury results in decreased stimulation of arterial baroreceptors and less engagement of feedback control as demonstrated by lower 1) spectral power of BP, 2) number (and percentages) of SBP ramps and barosequences, 3) cross-correlation magnitude of SBP/HR, 4) BEI, and 5) changes in delay between SBP/HR. Diminished vasomotion and impaired baroreflex regulation may be major contributors to decreased orthostatic tolerance following injury.     

Blockade of hypoxia-reoxygenation-mediated collagen type I expression and MMP activity by overexpression of TGF-beta1 delivered by AAV in mouse cardiomyocytes

Transforming growth factor (TGF)-beta(1) is one of the most pleiotropic and multifunctional peptides known. While the cardioprotective effect of TGF-beta(1) during ischemia is well known, the specific role of TGF-beta(1) in altering the cardiac remodeling process remains unclear. This study was designed to examine the regulation of hypoxia-reoxygenation-mediated collagen type I expression and activity of matrix metalloproteinases (MMPs) by overexpression of TGF-beta(1) in cultured HL-1 mouse cardiomyocytes. TGF-beta(1) was overexpressed in cardiomyocytes by transfection with adeno-associated virus (AAV)/TGF-beta(1)(Latent) or with AAV/TGF-beta(1)(ACT) (active TGF-beta(1)). Twenty-four hours of hypoxia followed by 3 h of reoxygenation (H-R) markedly enhanced (pro)collagen type I expression and activity of MMPs concomitant with an increase in reactive oxygen species (ROS) release and LOX-1 expression. Overexpression of TGF-beta(1) reduced these alterations induced by H-R. TGF-beta(1) overexpression also blocked H-R-mediated p38 and p44/42 MAPK activation. Transfection with AAV/TGF-beta(1)(ACT) was superior to that with AAV/TGF-beta(1)(Latent). These data for the first time demonstrate that H-R induces signals for cardiac remodeling in cardiomyocytes and TGF-beta(1) can modulate, possibly via antioxidant mechanism, these signals. These findings contribute to further understanding of the role of TGF-beta(1) in the cardiac remodeling process.     

Cross-talk between macrophages,smooth muscle cells,and endothelial cells in response to cigarette smoke: the effects on MMP2 and 9

The aim of the present study was to analyze the expression of sex-determining region Y-related high mobility group box 4 (SOX4) in non-small cell lung cancer (NSCLC) and its correlation with clinicopathologic characteristics, including the survival of NSCLC patients. To observe initially the expression status of SOX4 in lung squamous cell carcinoma and adenocarcinoma at gene expression omnibus. The expression of SOX4 mRNA and protein was examined in NSCLC tissues and normal lung tissues through real-time PCR and immunohistochemistry. Meanwhile, the relationship of SOX4 expression levels with clinical characteristics of 168 NSCLC patients was analyzed by immunohistochemistry. Univariate and multivariate analyses were performed to determine the association between SOX4 expression and prognosis of NSCLC patients. In our results, SOX4 expression was increased in NSCLC tissues compared with paired normal lung tissues in microarray data (GSE3268). SOX4 mRNA and protein expression were markedly higher in NSCLC tissues than in normal lung tissues (P = 0.001 and P = 0.001, respectively). Using immunohistochemistry, high levels of SOX4 protein were positively correlated with status of differentiated degree (high vs. middle, P = 0.004; high vs. low, P < 0.001), clinical stage (I–II vs. III–IV, P < 0.001), T classification (T1–T2 vs. T3–T4, P = 0.004), N classification (N0–N1 vs. N2–N3, P = 0.002), and M classification (M0 vs. M1, P = 0.011) in NSCLC. Moreover, the higher level of SOX4 expression was markedly correlated with poor overall survival in NSCLC patients (P < 0.001). Multivariate analysis suggested that increased SOX4 expression was a poor independent prognostic predictor for NSCLC patients (P = 0.002). In conclusion, SOX4 plays an important role on NSCLC progression and prognosis and may serve as a convictive prognostic biomarker for NSCLC patients.     

Exploring the structure and dynamics of nano-confined water molecules using molecular dynamics simulations

Confinement effects can lead to drastic changes in the structural and dynamical properties of water molecules. In this work, we have performed classical molecular dynamics simulations of endohedral fullerenes of type (H₂O)_n@C_m (n = 1, 12, 21, 62, 108 and m = 60, 180, 240, 500 and 720) to explore the effects of spherical confinement on water properties. It is shown that these confined water molecules can form distinct solvation pattern depending upon the available space inside the fullerene cavity. For the systems with smaller diameter, cage-like structure is predominant whereas bulk-like structure is observed for larger fullerenes. The orientational relaxation of these confined water molecules showed slower relaxation as the cavity diameter increases except for the (H₂O)₂₁@C₂₄₀. In this case, stable cage-like structure hinders the overall dynamics of the trapped water molecules. Finally, we have calculated the hydrogen bond lifetimes from the hydrogen bond time correlation functions and compared with that of bulk water.