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Background: Knee Osteoarthritis (KOA) is a prevalent and debilitating condition affecting millions worldwide, yet its underlying etiology remains poorly understood. Recent advances in neuroimaging and genetic methodologies offer new avenues to explore the potential neuropsychological contributions to KOA. This study aims to investigate the causal relationships between brainwide morphometric variations and KOA using a genetic epidemiology approach. Method: Leveraging data from 36,778 UK Biobank participants for human brain morphometry and 487,411 UK Biobank participants for KOA, this research employed a two-sample Mendelian Randomization (TSMR) approach to explore the causal effects of 83 brain-wide volumes on KOA. The primary method of analysis was the Inverse Variance Weighted (IVW) and Wald Ratio (WR) method, complemented by MR Egger and IVW methods for heterogeneity and pleiotropy assessments. A significance threshold of p < 0.05 was set to determine causality. The analysis results were assessed for heterogeneity using the MR Egger and IVW methods. Brain-wide volumes with Q_pval < 0.05 were considered indicative of heterogeneity. The MR Egger method was employed to evaluate the pleiotropy of the analysis results, with brain-wide volumes having a p-value < 0.05 considered suggestive of pleiotropy. Results: Our findings revealed significant causal associations between KOA and eight brain-wide volumes: Left parahippocampal volume, Right posterior cingulate volume, Left transverse temporal volume, Left caudal anterior cingulate volume, Right paracentral volume, Left paracentral volume, Right lateral orbitofrontal volume, and Left superior temporal volume. These associations remained robust after tests for heterogeneity and pleiotropy, underscoring their potential role in the pathogenesis of KOA. Conclusion: This study provides novel evidence of the causal relationships between specific brain morphometries and KOA, suggesting that neuroanatomical variations might contribute to the risk and development of KOA. These findings pave the way for further research into the neurobiological mechanisms underlying KOA and may eventually lead to the development of new intervention strategies targeting these neuropsychological pathways. [ABSTRACT FROM AUTHOR]

Osteoarthritis (OA) is a debilitating joint disorder characterized by the progressive degeneration of articular cartilage. Although the role of ion channels in OA pathogenesis is increasingly recognized, diagnostic markers and targeted therapies remain limited. In this study, we analyzed the GSE48556 dataset to identify differentially expressed ion channel-related genes (DEGs) in OA and normal controls. We employed machine learning algorithms, least absolute shrinkage and selection operator(LASSO), and support vector machine recursive feature elimination(SVM-RFE) to select potential diagnostic markers. Then the gene set enrichment analysis (GSEA) and gene set variation analysis (GSVA) were performed to explore the potential diagnostic markers' involvement in biological pathways. Finally, weighted gene co-expression network analysis (WGCNA) was used to identify key genes associated with OA. We identified a total of 47 DEGs, with the majority involved in transient receptor potential (TRP) pathways. Seven genes (CHRNA4, GABRE, HTR3B, KCNG2, KCNJ2, LRRC8C, and TRPM5) were identified as the best characteristic genes for distinguishing OA from healthy samples. We performed clustering analysis and identified two distinct subtypes of OA, C1, and C2, with differential gene expression and immune cell infiltration profiles. Then we identified three key genes (PPP1R3D, ZNF101, and LOC651309) associated with OA. We constructed a prediction model using these genes and validated it using the GSE46750 dataset, demonstrating reasonable accuracy and specificity. Our findings provide novel insights into the role of ion channel-related genes in OA pathogenesis and offer potential diagnostic markers and therapeutic targets for the treatment of OA. As society ages, the incidence of knee osteoarthritis continues to rise, bringing with it a series of social impacts and medical pressure. Despite the increasing recognition of the role of ion channels in the pathogenesis of OA, diagnostic markers and targeted therapies remain limited. This study investigated the role of TRP as possible diagnostic tools for OA. Seven TRP-related genes were identified as the best traits to distinguish OA from healthy samples, and then we constructed and validated risk scores for three key genes (PPP1R3D, ZNF101, and LOC651309) relevant to OA ion channel gene modules. Our findings provide novel insights into the role of ion channel-related genes in OA pathogenesis and offer a reference for further clinical diagnosis. [ABSTRACT FROM AUTHOR]

Background: Kidney renal clear cell carcinoma (KIRC) is a common and clinically significant subtype of kidney cancer. A potential therapeutic target in KIRC is disulfidptosis, a novel mode of cell death induced by disulfide stress. The aim of this study was to develop a prognostic model to explore the clinical significance of different disulfidptosis gene typings from KIRC. Methods: A comprehensive analysis of the chromosomal localization, expression patterns, mutational landscape, copy number variations, and prognostic significance of 10 disulfide death genes was conducted. Patients were categorized into distinct subtypes using the Non-negative Matrix Factorization (NMF) typing method based on disulfidptosis gene expression patterns. Weighted Gene Co-expression Network Analysis (WGCNA) was used on the KIRC dataset to identify differentially expressed genes between subtype clusters. A risk signature was created using LASSO-Cox regression and validated by survival analysis. An interaction between risk score and immune cell infiltration, tumor microenvironment characteristics and pathway enrichment analysis were investigated. Results: Initial findings highlight the differential expression of specific DRGs in KIRC, with genomic instability and somatic mutation analysis revealing key insights into their role in cancer progression. NMF clustering differentiates KIRC patients into subgroups with distinct survival outcomes and immune profiles, and hierarchical clustering identifies gene modules associated with key biological and clinical parameters, leading to the development of a risk stratification model (LRP8, RNASE2, CLIP4, HAS2, SLC22A11, and KCTD12) validated by survival analysis and predictive of immune infiltration and drug sensitivity. Pathway enrichment analysis further delineates the differential molecular pathways between high-risk and low-risk patients, offering potential targets for personalized treatment. Lastly, differential expression analysis of model genes between normal and KIRC cells provides insights into the molecular mechanisms underlying KIRC, highlighting potential biomarkers and therapeutic targets. Conclusion: This study contributes to the understanding of KIRC and provides a potential prognostic model using disulfidptosis gene for personalized management in KIRC patients. The risk signature shows clinical applicability and sheds light on the biological mechanisms associated with disulfide-induced cell death. [ABSTRACT FROM AUTHOR]

Cotton (Gossypium hirsutum L.) is a significant fiber crop. Being a major contributor to the textile industry requires continuous care and attention. Cotton is subjected to various biotic and abiotic constraints. Among these, biotic factors including cotton leaf curl virus (CLCuV) are dominant. CLCuV is a notorious disease of cotton and is acquired, carried, and transmitted by the whitefly (Bemisia tabaci). A cotton plant affected with CLCuVmay show a wide range of symptoms such as yellowing of leaves, thickening of veins, upward or downward curling, formation of enations, and stunted growth. Though there aremany efforts to protect the crop from CLCuV, long-term results are not yet obtained as CLCuV strains are capable of mutating and overcoming plant resistance. However, systemic-induced resistance using a gene-based approach remained effective until new virulent strains of CLCuV (like Cotton Leaf Curl Burewala Virus and others) came into existence. Disease control by biological means and the development of CLCuV-resistant cotton varieties are in progress. In this review, we first discussed in detail the evolution of cotton and CLCuV strains, the transmission mechanism of CLCuV, the genetic architecture of CLCuV vectors, and the use of pathogen and nonpathogen-based approaches to control CLCuD. Next, we delineate the uses of cutting-edge technologies like genome editing (with a special focus on CRISPR-Cas), next-generation technologies, and their application in cotton genomics and speed breeding to develop CLCuD resistant cotton germplasm in a short time. Finally, we delve into the current obstacles related to cotton genome editing and explore forthcoming pathways for enhancing precision in genome editing through the utilization of advanced genome editing technologies. These endeavors aim to enhance cotton's resilience against CLCuD. [ABSTRACT FROM AUTHOR]

Background: Although subclinical hypothyroidism (SCH) is related to abnormalities in left ventricular diastolic function, the use of levothyroxine as a regular treatment remains debatable. This meta-analysis aimed to determine whether thyroid hormone replacement therapy affects cardiac diastolic function in patients with SCH as measured by echocardiography. Methods: This meta-analysis included a search of the EMBASE, PubMed, Web of Science, and Cochrane Library databases from their inception to May 18, 2023, for studies analyzing cardiac morphology and functional changes in patients with SCH before and after thyroid hormone replacement. The outcome measures were cardiac morphology and diastolic and overall cardiac function, as assessed using ultrasound parameters (including ventricular wall thickness, chamber size, mitral wave flow, tissue Doppler, and speckle tracking). The quality of the studies was assessed using the Newcastle-Ottawa Scale. The standard mean differences (MDs) and 95% confidence intervals (CI) were calculated using fixed- or randomeffects models. Results: Seventeen studies met the inclusion criteria. A total of 568 patients participated and completed the follow-up. All studies specifically stated that serum thyrotropin levels returned to normal by the end of the study period. Compared with baseline levels, no significant morphological changes were observed in the heart. In terms of diastolic function, we discovered that the ratios of E-velocity to A-velocity (E/A) had greatly improved after thyroid hormone replacement therapy, whereas the ratios of the mitral inflow E wave to the tissue Doppler e' wave (E/e') had not. Global longitudinal strain (GLS) increased significantly after treatment with levothyroxine. Conclusion: In adult patients with SCH, thyroid hormone supplementation can partially but not completely improve parameters of diastolic function during the observation period. This meta-analysis was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 statement, an updated guideline for reporting systematic reviews (11) and was registered with INPLASY (INPLASY202320083). [ABSTRACT FROM AUTHOR]

Background: Interleukin-6 (IL-6) is essential for maintaining intestinal epithelial homeostasis. Although cold water-immersion restraint (CWIR) stress is commonly used to induce in vivo gastric injury, it also affects intestinal epithelial permeability. Although IL-6 is increased in response to acute physiological and psychological stress, its exact effects on the pathophysiology of the intestinal epithelium in response to acute CWIR stress remain unknown. Methods: We used IL-6 knockout (KO) mice with acute CWIR modeling to investigate the effect of IL-6 deficiency on intestinal epithelial morphology and pathological damage using histological staining assays under the acute stress. We detected jejunal epithelial apoptosis using TUNEL and standard molecular experiments. Results: CWIR caused intestinal epithelial damage, which was alleviated by the absence of IL-6, as evidenced by morphological changes and goblet cell and intestinal permeability alteration. IL-6 KO also reduced CWIR-mediated inflammatory levels and improved stress defense. Meanwhile, IL-6 deficiency decreased the intestinal epithelial apoptosis induced by CWIR administration. This IL-6 KO-led effect depended more on mitochondrial AIF signaling rather than the traditional caspase pathway. Conclusion: As a result, we concluded that acute CWIR-induced severe intestinal damage and jejunal epithelium apoptosis could be alleviated by IL-6 deficiency, implying a protective effect of IL-6 deficiency on the intestines under acute stress. The findings shed new light on treating CWIR-induced intestinal disorders by inhibiting IL-6 signaling. [ABSTRACT FROM AUTHOR]

Carbamates weaken the luminol-H2 O2 chemiluminescence (CL) catalyzed by sodium copper chlorophyll (SCC). The capacity to inhibit the CL of three carbamates is in the order of carbaryl (CBL) >carbofuran (CBF) >metolcarb (MTC). Mechanisms of carbamates inhibiting SCC-luminol-H2 O2 CL are investigated using fluorescence quenching and quantum chemistry simulations for the first time in this work. Carbamate-SCC interactions studied using fluorescence spectroscopy show that with the increasing concentration of the SCC, the fluorescence of carbamate is quenched regularly, and the quenching mechanism is a static quenching process. Binding constants (KB) of the three carbamates with SCC are CBL (4.39 × 105) >CBF (1.46 × 104) >MTC (2.16 × 103 L/mol), which is completely harmonious with the capacity to inhibit CL of the carbamates. Furthermore, the carbamate-SCC interaction energies from quantum chemistry simulations are CBL-porphyrin copper (PPCu) (-30.1), CBF-PPCu (-21.0), and MTC-PPCu (-19.9 kJ/mol), which is also identical to their inhibiting capacity. This provides further evidence that the formation of carbamate-SCC complexes reduces the SCC catalytic activity and the CL intensity decreases. In addition, a novel flow injection chemiluminescence method for the determination of carbamate was established based on carbamate inhibiting CL of the SCC-luminol-H2 O2 CL system under alkaline conditions. This work may contribute to the study of the mechanism of CL inhibition using fluorescence quenching and quantum chemistry calculation methods. [ABSTRACT FROM AUTHOR]

Comparative population genomics offers an opportunity to discover the signatures of artificial selection during animal domestication, however, their function cannot be directly revealed. We discover the selection signatures using genome-wide comparisons among 40 mallards, 36 indigenous-breed ducks, and 30 Pekin ducks. Then, the phenotypes are fine-mapped based on resequencing of 1026 ducks from an F2 segregating population generated by wild × domestic crosses. Interestingly, the two key economic traits of Pekin duck are associated with two selective sweeps with fixed mutations. A novel intronic insertion most possibly leads to a splicing change in MITF accounted for white duck down feathers. And a putative long-distance regulatory mutation causes continuous expression of the IGF2BP1 gene after birth which increases body size by 15% and feed efficiency by 6%. This study provides new insights into genotype-phenotype associations in animal research and constitutes a promising resource on economically important genes in fowl. [ABSTRACT FROM AUTHOR]

We present a new method of chemical quantification utilizing thermal analysis for the detection of relative humidity. By measuring the temperature change of a hydrophilically-modified temperature sensing element vs. a hydrophobically-modified reference element, the total heat from chemical interactions in the sensing element can be measured and used to calculate a change in relative humidity. We have probed the concept by assuming constant temperature streams, and having constant reference humidity (~0% in this case). The concept has been probed with the two methods presented here: (1) a thermistor-based method and (2) a thermographic method. For the first method, a hydrophilically-modified thermistor was used, and a detection range of 0-75% relative humidity was demonstrated. For the second method, a hydrophilically-modified disposable surface (sensing element) and thermal camera were used, and thermal signatures for different relative humidity were demonstrated. These new methods offer opportunities in either chemically harsh environments or in rapidly changing environments. For sensing humidity in a chemically harsh environment, a hydrophilically-modified thermistor can provide a sensing method, eliminating the exposure of metallic contacts, which can be easily corroded by the environment. On the other hand, the thermographic method can be applied with a disposable non-contact sensing element, which is a low-cost upkeep option in environments where damage or fouling is inevitable. In addition, for environments that are rapidly changing, the thermographic method could potentially provide a very rapid humidity measurement as the chemical interactions are rapid and their changes are easily quantified. [ABSTRACT FROM AUTHOR]

The corrosion-induced bond degradation between corroded steel strands and concrete is investigated in the present study. Ten pull-out specimens with different corrosion levels were tested to study corrosion's effects on concrete splitting, strand twisting, failure mode, and global force-displacement behavior. The local bond characteristics are discussed and derived based on the test results. Experimental results show that the bond behavior depends on the corrosion loss level and does not have a monotonic trend. Strand corrosion had beneficial effects on the bond strength when the corrosion loss is less than 6.24% in the current study. The corrosion loss significantly decreased the bond strength when the corrosion loss is greater than 9.26% or the corrosion-induced crack is wider than 0.67 mm. The strand will be pulled out instead of fracturing when the corrosion loss exceeds 8%. Corrosion affects the bond strength more significantly than the tension strength for severe corrosion conditions. A simplified model is proposed to predict the residual bond strength between corroded strands and concrete. The proposed model's predictions are validated with experimental data. Several conclusions and suggestions for future work are drawn based on the conducted study. [ABSTRACT FROM AUTHOR]

Bond degradation–induced incompatible strain between corroded steel bars and concrete is investigated in this paper. A compatibility coefficient and a nonlinear analysis method are introduced to quantify the incompatible strain. The effect of corrosion losses, loading levels, loading conditions, and the span-to-depth ratio on the incompatible strain are investigated in detail. The incompatible strain effects on the beam flexural strength have been clarified. A simplified formula is then proposed to calculate the ultimate compatibility coefficient. Further, an attempt has also been made to incorporate this coefficient into the flexural strength prediction for corroded RC beams. Results show that the incompatible strain depends on the loading levels and corrosion losses. Corrosion has a negligible effect on the incompatible strain until the corrosion loss exceeds a critical value. For severely corroded beams, the incompatible strain increases rapidly as the loading level increases and saturates to a constant value when the loading level is high. The critical corrosion loss and the final constant incompatible strain are significantly affected by span-to-depth ratio and loading condition, respectively. [ABSTRACT FROM AUTHOR]

Structural health monitoring has been studied by a number of researchers as well as various industries to keep up with the increasing demand for preventive maintenance routines. This work presents a novel method for reconstruct prompt, informed strain/stress responses at the hot spots of the structures based on strain measurements at remote locations. The structural responses measured from usage monitoring system at available locations are decomposed into modal responses using empirical mode decomposition. Transformation equations based on finite element modeling are derived to extrapolate the modal responses from the measured locations to critical locations where direct sensor measurements are not available. Then, two numerical examples (a two-span beam and a 19956-degree of freedom simplified airfoil) are used to demonstrate the overall reconstruction method. Finally, the present work investigates the effectiveness and accuracy of the method through a set of experiments conducted on an aluminium alloy cantilever beam commonly used in air vehicle and spacecraft. The experiments collect the vibration strain signals of the beam via optical fiber sensors. Reconstruction results are compared with theoretical solutions and a detailed error analysis is also provided. [ABSTRACT FROM AUTHOR]

An analytical model is proposed in this paper to evaluate the residual flexural strength for corroded RC beams. The steel slipping caused by bond degradation is included in the proposed model. Various failure modes of beams caused by different types of steel bar anchorage are also incorporated in the model. The bond degradation is considered as a function of the corrosion rate of steel. Bond degradation transfers prematurely the effective bond force, resulting in incompatible strain within the slipping region. A new method is developed to quantify the slipping region based on the transfer theory of effective bond force. Next, a new strain-incompatibility analysis method is proposed to determine the deteriorated flexural strength. The accuracy of the model is validated by experimental observations on the beams with different steel anchorage under corrosive environments. Results show that the proposed model can provide a reasonable prediction for the flexural strength and failure modes. The strain incompatibility of the corroded beams is sensitive to corrosion loss and loading position. It becomes very significant for the beams with a corrosion loss greater than 7% and the beam with a concentrated load at the midspan. [ABSTRACT FROM AUTHOR]

A general probabilistic fatigue-crack growth prediction methodology for accurate and efficient damage prognosis is proposed in this paper. The methodology is based on an equivalent stress transformation and the inverse first-order reliability method (IFORM). The equivalent stress transformation aims to transform the random variable amplitude loading to an equivalent constant amplitude loading spectrum. The proposed transformation avoids the cycle-by-cycle calculation under general random variable amplitude loadings. An IFORM is used to evaluate the probabilistic fatigue-crack growth behavior and to further enhance the computational efficiency. The computational cost of the proposed study is significantly reduced compared with the direct Monte Carlo simulation. Thus, the proposed method is very suitable for real-time damage prognosis because of its high computational efficiency. Numerical examples are used to demonstrate the proposed method. Various experimental data under variable amplitude loadings are collected for model validation. [ABSTRACT FROM AUTHOR]

An experimental study is proposed to compare the corrosion-induced flexural behavior deterioration of beams with various bar types and bar diameters. The proposed study aims to distinguish the effects of the corrosion of different rebars on the flexural behavior of reinforced concrete (RC) beams. Twenty-two RC beams were designed and four variables were considered: the type and the diameter of reinforcement, corrosion loss, and concrete cover. Corrosion was induced in the laboratory using an accelerated corrosion technique. The corrosion-induced strength loss for two types of steel bars is discussed. Extensive statistical analysis is performed to compare the flexural performance of beams with different rebars. The experimental results show that (1) corrosion has a more significant effect on the flexural behavior deterioration in beams with smooth rebars than in beams with deformed rebars; (2) the corrosion-induced performance deterioration has a monotonic decreasing relationship with reinforcement size; and (3) large-diameter steel bars are more appropriate for structural safety. [ABSTRACT FROM AUTHOR]

Background: The replacement of lost cardiac tissues by regenerated myocardium would be a therapeutic ideal for myocardial infarction. The objective of this study was therefore to evaluate the ability of an active fraction that was isolated from Rosa laevigata Michx in therapeutic cardiomyogenesis in a myocardial infarction rat model. Methods: The myocardial infarction animal model was induced by the permanent ligation of the left anterior descending coronary artery in rats. The active fraction, which improves the survival rate and prevents ischemic reperfusion damage, was used to test the therapeutic effect of this fraction on myocardial infarction. Results: The oral administration of the active fraction for 4 weeks could progressively restore the decreased cardiac function due to myocardial infarction. The significantly improved cardiac function was probably attributed to the active fraction-induced myocardial regeneration, which replaced the lost cardiac tissues in the myocardial infarction animals. Conclusions: The property of this active fraction appears to be entirely novel and may provide a potential therapeutic alternative for myocardial infarction. [ABSTRACT FROM AUTHOR]

MicroRNA (miRNA) is an important regulator of cell differentiation and function. Mechanical strain is important in the growth and differentiation of osteoblasts. Therefore, mechanresponsive miRNA may be important in the response of osteoblasts to mechanical strain. The purpose of the present study was to select and identify the mechanoresponsive miRNAs of osteoblasts. Mouse osteoblastic MC3T3-E1 cells were cultured in cell culture dishes and stimulated with a mechanical tensile strain of 2,50 με at 0.5 Hz, and the activity of alkaline phosphatase (ALP), mRNA levels of ALP, osteocalcin (OCN), and collagen type I (Col I), and protein levels of bone morphogenetic proteins (BMPs) inthe cell culture medium were assayed. Following miRNA microarray and reverse transcription-quantitative polymerase chain reaction analyses, differentially expressed miRNAs in the mechanically strained cells and unstrained cells were selected and identified. Using bioinformatics analysis, the target genes of the miRNAs were then predicted. The results revealed that the mechanical strain of 2,500 με increased the activity of ALP, the mRNA levels of ALP, OCN and Col I, and the protein levels of bone morphogenetic protein(BMP)-2 and BMP-4 Continuous mechanical stimulation for 8 h had the most marked stimulant effects. miR-218, miR-191*, miR-3070a and miR-33 were identified as differentially expressed miRNAs in the mechanically strained MC3T3-E1 cells. Certain target genes of these four miRNAs were involved in osteoblastic differentiation. These findings indicated that a mechanical strain of 2,500 με, particularly for a period of 8 h, promoted osteoblastic differentiation, and the four mechanoresponsive miRNAs identified may be a potential regulator of osteoblastic differentiation and their response to mechanical strain. [ABSTRACT FROM AUTHOR]

Insulin and adrenergic stimulation are two divergent regulatory systems that may interact under certain pathophysiological circumstances. Here, we characterized a complex consisting of insulin receptor (IR) and β2- adrenergic receptor (β2AR) in the heart. The IR/β2AR complex undergoes dynamic dissociation under diverse conditions such as Langendorff perfusions of hearts with insulin or after euglycemic-hyperinsulinemic clamps in vivo. Activation of IR with insulin induces protein kinase A (PKA) and G-protein receptor kinase 2 (GRK2) phosphorylation of the β2AR, which promotes β2AR coupling to the inhibitory G-protein, Gi. The insulin-induced phosphorylation of β2AR is dependent on IRS1 and IRS2. After insulin pretreatment, the activated β2AR-Gi signaling effectively attenuates cAMP/PKA activity after β-adrenergic stimulation in cardiomyocytes and consequently inhibits PKA phosphorylation of phospholamban and contractile responses in myocytes in vitro and in Langendorff perfused hearts. These data indicate that increased IR signaling, as occurs in hyperinsulinemic states, may directly impair βAR-regulated cardiac contractility. This β2AR-dependent IR and βAR signaling cross-talk offers a molecular basis for the broad interaction between these signaling cascades in the heart and other tissues or organs that may contribute to the pathophysiology of metabolic and cardiovascular dysfunction in insulin-resistant states. [ABSTRACT FROM AUTHOR]

Background: The recent approval of 4th generation HIV tests has forced many laboratories to decide whether to shift from 3rd to these tests. There are limited published studies on the comparative evaluation of these two different assays. We compare the performance of fourth-generation electrochemiluminescence immunoassay (ChIA) and third-generation enzyme linked immunosorbent assay (EIA) for human immunodeficiency virus (HIV) screening and gauge whether the shift from EIA to ChIA could be better in a multiethnic region of China. Methodology/Principal Findings: We identified a large number of routine specimens (345,492) using two different assays from Jan 2008 to Aug 2011 in a teaching hospital with high sample throughput. Of the 344,596 specimens with interpretable HIV test results, 526(0.23%) of 228,761 using EIA and 303(0.26%) of 115,835 using ChIA were HIV-1 positive. The false-positive rate of EIA was lower than that of ChIA [0.03% vs. 0.08%, odds ratio 0.33 (95% confidence interval 0.24, 0.45)]. The positive predictive value (PPV) of EIA (89.6%) was significantly higher than that of ChIA (76.1%) (,0.001), reflecting the difference between the two assays. The clinical sensitivities of two assays in this study were 99.64% for EIA and 99.88% for ChIA. Conclusion: Caution is needed before shifting from 3rd to 4th generation HIV tests. Since none of these tests are perfect, different geographic and ethnic area probably require different considerations with regard to HIV testing methods, taking into account the local conditions. [ABSTRACT FROM AUTHOR]

The article presents a study on the optimal time point for the transplantation of differentiated neural stem cells (NSCs). The study involves the use of NSCs that were induced with retinoic acid to differentiate and were harvested after 3-6 weeks. A peak rate of cells that differentiate into neurons and robust growth was exhibited in NSCs that were induced for four days. The result shows that the optimal point for the transplantation of NSCs is after four days of induced differentiation.

The polymerizations of n-butyl methylacrylate (nBMA) were carried out using bis(β-ketoamino)nickel(II) complexes (Ni[CH3C(O)CHC(NR)CH3]2: R = phenyl, 1; R = naphthyl, 2) in combination with methylaluminoxane (MAO) in toluene. The effect of parameters such as polymerization temperature, Al/Ni molar ratios, polymerization time, and monomer concentration, on catalytic polymerization activity and polymer molecular weights, were examined in detail. Both of the nickel(II) catalytic systems exhibited moderate activity, and produced P(nBMA) with high molecular weight and relatively broad molecular weight distribution (Mw/Mn=2.0∼3.0. The obtained polymer has been characterized by means of FTIR, ¹H NMR, 13C NMR, DSC, and WAXD technique and was confirmed to be syndio-rich stereospecific P(nBMA). [ABSTRACT FROM AUTHOR]

Norbornene polymerizations proceeded in toluene with bis(β‐ketoamino)nickel(II) {Ni[CH3C(O)CHC(NR)CH3]2 [R = phenyl (1) or naphthyl (2)]} complexes as the catalyst precursors and the organo‐Lewis compound tris(pentafluorophenyl)borane [B(C6F5)3] as a unique cocatalyst. The polymerization conditions, such as the cocatalyst/catalyst ratio (B/Ni), catalyst concentration, monomer/catalyst ratio (norbornene/Ni), polymerization temperature, and polymerization time, were studied in detail. Both bis(β‐ketoamino)nickel(II)/B(C6F5)3 catalytic systems showed noticeably high conversions and activities. The polymerization activities were up to 3.64 × 107 g of polymer/mol of Ni h for complex 1/(B(C6F5)3 and 3.80 × 107 g of polymer/mol of Ni h for complex 2/B(C6F5)3, and very high conversions of 90–95% were maintained; both polymerizations provided high‐molecular‐weight polynorbornenes with molecular weight distributions (weight‐average molecular weight/number‐average molecular weight) of 2.5–3.0. The achieved polynorbornenes were confirmed to be vinyl‐addition and atactic polymers through the analysis of Fourier transform infrared, 1H NMR, and 13C NMR spectra, and the thermogravimetric analysis results showed that the polynorbornenes exhibited good thermal stability (decomposition temperature > 410 °C). © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4733–4743, 2007 [ABSTRACT FROM AUTHOR]

Styrene (St) was polymerized in toluene solution by using bis(β‐ketoamino)nickel(II) complex as the catalyst precursor and methylaluminoxane (MAO) as the cocatalyst. The polymerization conditions, such as Al : Ni ratio, monomer concentration, reaction temperature, and polymerization time, were studied in detail. Both of the bis(β‐ketoamino)nickel(II)/MAO catalytic systems exhibited higher activity for polymerization of styrene, and polymerization gave moderate molecular weight of polystyrene with relatively narrow molecular weight distribution (Mw/Mn < 1.6). The obtained polymer was confirmed to be atactic polystyrene by analyzing the stereo‐triad distributions mm, mr, and rr of aromatic carbon C1 in NMR spectrum of the polymer. The mechanism of the polymerization was also discussed and a metal–carbon coordination mechanism was proposed. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 [ABSTRACT FROM AUTHOR]

The aim of this article was to examine the protective effect of Chinese traditional medicine angelica on human umbilical vein endothelial cells (HUVECs, ECV[SUB304]) from injury induced by hyperlipidemic serum (HLS) and to study the underlying mechanism. Spectrophotometer and immunocytochemical methods were used to detect the content of nitric oxide (NO) in suspension and expression of intercellular adhesion molecule-1 (ICAM-1), transforming growth factor β[SUB1] (TGF β[SUB1]), basic fibroblast growth factor (bFGF) on the cell surface, respectively. After incubated with 50 µl/ml HLS for 24 hours, expression of ICAM-1 and bFGF in ECs was significantly increased, while expression of TGFβ[SUB1] and the release of NO from ECs were significantly decreased. Ali these effect of HLS on ECs can be reversed by angelica significantly. The above effect of angelica may be related to its anti-atherosclerotic action. Our findings provided experimental basement for the clinical application of angelica to prevent the development of atherosclerosis. [ABSTRACT FROM AUTHOR]

This experiment was designed to study the antiatherogenesis action of angelica injection and its mechanisms on classic atherosclerotic rabbit model. Eighteen Japanese rabbits were divided randomly into three groups: a control group, a high-lipid group and an angelica group; and common forage, high lipid forage and high lipid adding angelica injection were given to each group accordingly. At the end of the tenth week, blood samples were obtained through carotid artery intubation for evidence of serum lipids and hemorheology. Thoracic aorta were prepared for measurement of the plaque area. The results showed that (1) the plaque area in the high-lipid group was larger than in the angelica group: (35.58 ± 7.25% vs 63.31 ± 7.46%); (2) serum lipids level in the high-lipid group and angelica group were significantly higher than those in the control group (p < 0.01). Apart from triglyceride (TG), there was no difference of total cholesterol (Tch), high-density lipoprotein cholesterol (HDL-ch), and low-density lipoprotein cholesterol (LDL-ch) between the high-lipid group and the angelica group; (3) angelica increased whole blood viscosity, hematocrit and fibrinogen under hyperlipidemic conditions. We concluded that angelica can inhibit rabbit aorta atherogenesis through decreasing the serum triglyceride concentration and its effects on hemorheology. [ABSTRACT FROM AUTHOR]

By using the conservation laws and the method of variational principle, an improved Arnol'd's second nonlinear stability theorem for the two-dimensional multilayer quasi-geostrophic model in periodic channel is obtained. [ABSTRACT FROM AUTHOR]

Proves that the linear stability criterion for Eady's problem is also a nonlinear stability one. Study of the nonlinear stability of baroclinic flow; Three-dimensional, baroclinic, geostrophic flow on an f-plane; Disturbance potential enstrophy.

Arnol′d′s second nonlinear stability criterion for motions governed by a general multilayer quasi-geostrophic model is established. The model allows arbitrary density jumps and layer thickness, and at the top and the bottom of the fluid, the boundary condition is either free or rigid. The criterion is obtained by the establishment of the upper bounds of disturbance energy and potential enstrophy in terms of the initial disturbance field. [ABSTRACT FROM AUTHOR]

The second author studied the nonlinear stability of N-layer quasi-geostrophic flow subject to perturbations of parameters and initial data, and established the stability criteria for the flow in question, which involve finding out the lowest eigenvalue of an elliptic boundary value problem. In this paper when the domain is a periodic zonal channel, a formula of the lowest eigenvalue is established, which is useful for further studies and practical applications. [ABSTRACT FROM AUTHOR]

The article presents discussion on the paper ""Bridge Remaining Strength Prediction Integrated with Bayesian Network and In Situ Load Testing" which establishes a Bayesian network-based framework for predicting remaining bridge strength by using in situ load testing. Topics discussed include a model error factor for structural stiffness degradation and effects of bar diameter, bar type, and concrete cover on structural stiffness.

The state and distribution of the cytoskeleton are intimately related to the endothelial integrity. Vasodilator stimulated phosphoprotein (VASP) is a crucial regulator of actin which is identified as main component of microfilaments in cytoskeleton. Activated PKC can induce VASP phosphorylation. It is reported that ox-LDL can activate PKC pathway in endothelial cells through the specific receptor binding. In order to investigate the role of VASP phosphorylation in ox-LDL-induced changes of cytoskeleton in endothelial cell and identify whether PKC participates the phosphorylation of VASP induced by ox-LDL, the endothelial cell line (ECV304) was divided into 6 groups with different condition, which including the Control (normal culture), PKC activator(PMA 0.1µM), PKC inhibitor (GF109203X 1µM), ox-LDL(200µM), PMA+ox-LDL group, and GF109203X+ox-LDL group. We observed that the formation of stress fiber increased in ox-LDL, PMA and ox-LDL+PMA groups, but actin clustered in the peripheral region of the cells decreased, while phosphorylated VASP localized to cell-cell junctions and the lengthwise of actin cytoskeleton through confocal microscopy. The expression of phosphorylated VASP and PKC activity also increased in above groups, especially in ox-LDL+PMA group. But the difference between GF109203X and Control group has no statistical significance. These results indicate that the phosphorylation of VASP mediates the changes of cytoskeleton induced by ox-LDL in endothelial cells; PKC is one of the regulated kinases of the phosphorylation of VASP induced by ox-LDL. [ABSTRACT FROM AUTHOR]