Sensitivity and specificity of placental proteins for gestational age screening: An exploratory study.

Objective: To examine the possibility that serum or urine concentrations of pregnancy-associated plasma protein A (PAPP-A), a disintegrin and metalloproteinase 12 (ADAM-12), placental growth factor (PlGF), human placental lactogen (HPL), glypican-3, pregnancy specific beta-1-glycoprotein 1 (PSG-1) or prolactin could predict gestational age (GA) >70 days, the currently recommended limit for medical abortion in the United States.

Study Design: In this exploratory observational study, we collected serum and urine specimens from 245 healthy individuals with singleton intrauterine pregnancies at GA <40 weeks by ultrasound. We assayed the serum specimens for all seven proteins and the urine specimens for PAPP-A and ADAM-12.

Quantitative dynamics of hepatitis B basal core promoter and precore mutants before and after HBeAg seroconversion.

Background & Aims: Hepatitis B e antigen (HBeAg) seroconversion is an important clinical and virological "landmark" during chronic hepatitis B virus (HBV) infection. Mutant viruses carrying the precore G1896A and/or the basal core promoter (BCP) A1762T/G1764A mutations are associated with HBeAg seroconversion. However, the exact role of these mutants in HBeAg seroconversion remains unclear, partly because the evolution of these mutant viruses before and after seroconversion has not been well studied.

Quantification of complex precore mutations of hepatitis B virus by SimpleProbe real time PCR and dual melting analysis.

Background: Hepatitis B virus (HBV) precore G1896A mutation is associated with Hepatitis B e antigen (HBeAg) seroconversion. This mutation and the adjacent G1899A mutation also appear to associate with increased risk of hepatocellular carcinoma. Quantitative mutant dynamics may help determine the potential of these mutants as clinical biomarkers.

Ultrasensitive quantification of hepatitis B virus A1762T/G1764A mutant by a SimpleProbe PCR using a wild-type-selective PCR blocker and a primer-blocker-probe partial-overlap approach.

Hepatitis B virus (HBV) carrying the A1762T/G1764A double mutation in the basal core promoter (BCP) region is associated with HBe antigen seroconversion and increased risk of liver cirrhosis and hepatocellular carcinoma (HCC). Quantification of the mutant viruses may help in predicting the risk of HCC. However, the viral genome tends to have nucleotide polymorphism, which makes it difficult to design hybridization-based assays including real-time PCR.

Fibronectin growth factor-binding domains are required for fibroblast survival.

Fibronectin (FN) is required for embryogenesis, morphogenesis, and wound repair, and its Arg-Gly-Asp-containing central cell-binding domain (CCBD) is essential for mesenchymal cell survival and growth. Here, we demonstrate that FN contains three growth factor-binding domains (FN-GFBDs) that bind platelet-derived growth factor-BB (PDGF-BB), a potent fibroblast survival and mitogenic factor. These sites bind PDGF-BB with dissociation constants of 10-100 nM.

Rapid and sensitive detection of hepatitis B virus 1762T/1764A double mutation from hepatocellular carcinomas using LNA-mediated PCR clamping and hybridization probes.

The 1762T/1764A double mutation of the hepatitis B virus (HBV) basal core promoter has been suggested to be a potential biomarker for hepatocellular carcinoma (HCC) among individuals with chronic HBV infection. In this study, a real-time PCR assay is established using the hybridization probes and an oligonucleotide clamp containing locked nucleic acids (LNAs). The LNA-containing oligonucleotide clamp specific for the wild type HBV is able to suppress the amplification of the wild type HBV templates.

Cell adaptation to a physiologically relevant ECM mimic with different viscoelastic properties.

To successfully induce tissue repair or regeneration in vivo, bioengineered constructs must possess both optimal bioactivity and mechanical strength. This is because cell interaction with the extracellular matrix (ECM) produces two different but concurrent signaling mechanisms: ligation-induced signaling, which depends on ECM biological stimuli, and traction-induced signaling, which depends on ECM mechanical stimuli. In this report, we provide a fundamental understanding of how alterations in mechanical stimuli alone, produced by varying the viscoelastic properties of our bioengineered construct, modulate phenotypic behavior at the whole-cell level.

Fibronectin functional domains coupled to hyaluronan stimulate adult human dermal fibroblast responses critical for wound healing.

Fibronectin (FN) facilitates dermal fibroblast migration during normal wound healing. Proteolytic degradation of FN in chronic wounds hampers healing. Previously, three FN functional domains (FNfd) have been shown to be sufficient for optimal adult human dermal fibroblast migration.

Fibronectin's central cell-binding domain supports focal adhesion formation and Rho signal transduction.

Fibroblast adhesion to fibronectin (FN) induces formation of focal adhesions (FAs), structures that have significant effect on cell migration and signaling. FA formation requires actomyosin-based contractility that is regulated by Rho-dependent myosin light chain (MLC) phosphorylation. Previous studies indicated that the FN central cell-binding (and integrin-binding) domain (CBD) is insufficient for FA formation and that the major heparin-binding domain (HepII) facilitates FA formation in a Rho-dependent manner.

Three-dimensional migration of human adult dermal fibroblasts from collagen lattices into fibrin/fibronectin gels requires syndecan-4 proteoglycan.

Fibroblast migration from the peri-wound collagenous stroma into the fibrin-laden wound is critical for granulation tissue formation and subsequent healing. Previously we found that fibroblast transmigration from a collagen matrix into a fibrin matrix required fibronectin (FN). Integrins alpha4beta1, alpha5beta1, and alphavbeta3 and dermatan sulfate CD44 were required for this invasive migration.

Disruption of Rho signal transduction upon cell detachment.

Serum-soluble factors play a dominant role in the activation of the small GTPase RhoA. Cell adhesion also modulates RhoA activity but the effect is modest in the absence of serum. Here, we show that cell adhesion is required for serum-stimulated Rho signal transduction leading to myosin light chain (MLC) phosphorylation.

Cooperative regulation by Rac and Rho of agrin-induced acetylcholine receptor clustering in muscle cells.

A key aspect of neuromuscular synapse formation is the clustering of muscle acetylcholine receptors (AChR) at synaptic sites in response to neurally secreted agrin. Agrin-induced AChR clustering in cultured myotubes proceeds via the initial formation of small microclusters, which then aggregate to form AChR clusters. Here we show that the coupling of agrin signaling to AChR clustering is dependent on the coordinated activities of Rac and Rho GTPases.