Transdifferentiation of cardiac fibroblasts,a fetal factor in anti-SSA/Ro-SSB/La antibody-mediated congenital heart block

The signature lesion of autoantibody-associated congenital heart block (CHB) is fibrosis of the conducting tissue. To date, participation of myofibroblasts in the cascade to injury has been unexplored. The importance of myofibroblast/macrophage cross-talk is demonstrated by the novel finding of these cell types in the heart of a neonate dying of CHB. This clue to pathogenesis prompted consideration of the mechanism by which maternal anti-SSA/Ro-SSB/La Abs initiate an inflammatory response and promote fibrosis. Isolated cardiocytes from 16-24 wk abortuses were rendered apoptotic by exposure to poly (2-) hydroxyethylmethacrylate; flow cytometry confirmed surface expression of Ro/La. Apoptotic cardiocytes were incubated with affinity-purified Abs to 52 and 60 kDa Ro from CHB mothers (opsonized) or IgG fractions from healthy donors (nonopsonized). Macrophages cultured with opsonized apoptotic cardiocytes expressed proinflammatory markers, supported by a three-fold increase in active alpha(V)beta(3) integrin. Fetal cardiac fibroblasts exposed to supernatants obtained from macrophages incubated with opsonized apoptotic cardiocytes (but not nonopsonized) dramatically increased expression of the myofibroblast marker alpha-smooth muscle actin (SMAc). The "opsonized" supernatant reversed an inhibitory effect of the "nonopsonized" supernatant on proliferation of fibroblasts (120 vs 69%, p < 0.05). Parallel experiments examined the effects of two cytokines and their neutralizing Abs on fibroblasts. TGFbeta1 increased SMAc staining but decreased proliferation. TNF-alpha did not affect either readout. Addition of anti-TGFbeta1 Abs to the "opsonized" supernatant blocked SMAc expression but increased proliferation, while anti-TNF-alpha blocking Abs had no effects. These data suggest that transdifferentiation of cardiac fibroblasts to a scarring phenotype is a pathologic process initiated by maternal Abs.     

Decrease in cell viability in an RMF,sigma(38), and OmpC triple mutant of Escherichia coli

In a speG-disrupted Escherichia coli mutant, which cannot metabolize spermidine to acetylspermidine, addition of spermidine to the medium caused a decrease in cell viability at the late stationary phase of growth. There were parallel decreases in the levels of ribosome modulation factor (RMF), the sigma(38) subunit of RNA polymerase, and the outer membrane protein C (OmpC). To clarify that these three proteins are strongly involved in cell viability, the rmf, rpoS (encoding sigma(38)), and ompC genes were disrupted. Viability of the triple mutant decreased to less than 1% of normal cells. The triple mutant had a reduced cell viability compared to any combination of double mutants, which also had a reduced cell viability. The single rmf and rpoS, but not ompC, mutant only slightly reduced cell viability. The results indicate that cooperative functions of these three proteins are necessary for cell viability at the late stationary phase. The triple mutant had a reduced level of ribosomes and of intracellular cations.     

Changes in cell-mediated immunity in kidney transplant recipients with active CMV infection

This study was aimed at determining (a) the extent of proliferation of peripheral blood mononuclear cells (PBMC) in response to stimulation by cytomegalovirus (CMV)-infected fibroblasts and (b) the levels of Th1 and Th2 cytokine production in kidney transplant recipients with and without active CMV infection. Thirty patients with, and 39 without active CMV infection, diagnosed by a CMV antigenemia assay (AA), were studied. PBMC of patients with active CMV infection showed significantly lower proliferation than those without ongoing CMV infection (P<0.0001). The levels of Th2-type cytokines (interleukin (IL-) 4 and IL-10) in AA-negative and AA-positive kidney transplant recipients were similar but the levels of the Th1-type cytokines interferon-gamma, tumor necrosis factor-alpha (P<0.05) and IL-2 were significantly lower in AA-positive kidney transplant recipients (P<0.0005).     

Oxygen-dependent signaling in pulmonary vascular smooth muscle

The pulmonary circulation constricts in response to acute hypoxia, which is reversible on reexposure to oxygen. On exposure to chronic hypoxia, in addition to vasoconstriction, the pulmonary vasculature undergoes remodeling, resulting in a sustained increase in pulmonary vascular resistance that is not immediately reversible. Hypoxic pulmonary vasoconstriction is physiological in the fetus, and there are many mechanisms by which the pulmonary vasculature relaxes at birth, principal among which is the acute increase in oxygen. Oxygen-induced signaling mechanisms, which result in pulmonary vascular relaxation at birth, and the mechanisms by which chronic hypoxia results in pulmonary vascular remodeling in the fetus and adult, are being investigated. Here, the roles of cGMP-dependent protein kinase in oxygen-mediated signaling in fetal pulmonary vascular smooth muscle and the effects of chronic hypoxia on ion channel activity and smooth muscle function such as contraction, growth, and gene expression were discussed.     

Influence of processing-induced phase transformations on the dissolution of theophylline tablets

The object of this investigation was to evaluate the influence of (1) processing-induced decrease in drug crystallinity and (2) phase transformations during dissolution, on the performance of theophylline tablet formulations. Anhydrous theophylline underwent multiple transformations (anhydrate --> hydrate --> anhydrate) during processing. Although the crystallinity of the anhydrate obtained finally was lower than that of the unprocessed drug, it dissolved at a slower rate. This decrease in dissolution rate was attributed to the accelerated anhydrate to hydrate transformation during the dissolution run. Water vapor sorption studies proved to be a good predictor of powder dissolution behavior. While a decrease in crystallinity was brought about either by milling or by granulation, the effect on tablet dissolution was pronounced only in the latter. Tablet formulations prepared from the granules exhibited higher hardness, longer disintegration time, and slower dissolution than those containing the milled drug. The granules underwent plastic deformation during compression resulting in harder tablets, with delayed disintegration. The high hardness coupled with rapid anhydrate --> hydrate transformation during dissolution resulted in the formation of a hydrate layer on the tablet surface, which further delayed tablet disintegration and, consequently, dissolution. Phase transformations during processing and, more importantly, during dissolution influenced the observed dissolution rates. Product performance was a complex function of the physical state of the active and the processing conditions.     

Sequence and structural requirements for optimal guide RNA-directed insertional editing within Leishmania tarentolae

The coding sequence of several mitochondrial mRNAs of the trypanosomatid family of protozoa is created by the guide RNA-directed insertion and deletion of uridylates (Us). Selection-amplification was used to explore the sequence and structure of the guide RNA and mRNA required for efficient insertional editing within a mitochondrial extract prepared from Leishmania tarentolae. This study identifies several novel features of the editing reaction in addition to several that are consistent with the previous mutagenesis and phylogenetic analysis of the reaction in Trypanosoma brucei, a distantly related trypanosomatid. Specifically, there is a strong bias against cytidines 5' of the editing sites and guanosines immediately 3' of guiding nucleotides. U insertions are directed both 5' and 3' of a genomically encoded U, which was previously assumed not to occur. Base pairing immediately flanking an editing site can significantly stimulate the editing reaction and affect the reaction fidelity but is not essential. Likewise, single-stranded RNA in the region upstream of the editing site, not necessarily immediately adjacent, can facilitate editing but is also not essential. The editing of an RNA containing many of the optimal features is linear with increasing quantities of extract permitting specific activity measurements to be made that are not possible with previously described T. brucei and L. tarentolae assays. The reaction catalyzed by the L. tarentolae extract can be highly accurate, which does not support a proposed model for editing that was based largely on the inaccuracy of an earlier in vitro reaction.     

A review of some issues and identification of some barriers in the implementation of FMS

Global competition, advancements in technology and ever changing customers’ demand have made the manufacturing companies to realize the importance of flexible manufacturing systems (FMS). These organizations are looking at FMS as a viable alternative to enhance their competitive edge. But, implementation of this universally accepted and challenging technology is not an easy task. A large number of articles have been reviewed and it is found that the existing literature lacks in providing a clear picture about the implementation of FMS. In this paper, work of various researchers has been studied and it is found that it is really a very difficult task for any organization to transform into FMS on the basis of existing research results. A wide gap exists between the proposed approaches/algorithms for the design of different components of FMS and the real-life complexities. Besides describing the gap in various issues related to FMS, some barriers, which inhibit the adaptation and implementation of FMS, have also been identified in this paper.     

Biosynthesis of copper oxide nanoparticles using Enicostemma axillare (Lam.) leaf extract

In the present study copper oxide nanoparticles (CuONPs) were synthesized via simple and eco-friendly green route using leaf extract of Enicostemma axillare (Lam.). Characterization of synthesized nanoparticles (NPs) was undertaken. The characteristic absorption peak of CuONPs was in range 264nm in UV–Vis spectrum. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) studies revealed the morphological and structural character of green NPs. The mean particle size was calculated to 30nm. Energy dispersive spectroscopy (EDS) showed high intense metallic peak of copper (Cu), oxygen (O) and low intense peaks of carbon (C), sulfur (S), phosphorus (P) elements due to the capping action of biomolecules of plant extract in CuONPs formation. The X-ray diffraction (XRD) pattern showed distinctive peaks corresponding to (200), (211) and (310) planes revealing the high crystalline nature of synthesized CuONPs with a primitive phase. Zeta potential and size distribution of synthesized green NPs was concluded by Dynamic light scattering (DLS) studies.     

Shape based virtual screening and molecular docking towards designing novel pancreatic lipase inhibitors

Increase in obesity rates and obesity associated health issues became one of the greatest health concerns in the present world population. With alarming increase in obese percentage there is a need to design new drugs related to the obesity targets. Among the various targets linked to obesity, pancreatic lipase was one of the promising targets for obesity treatment. Using the in silico methods like structure based virtual screening, QikProp, docking studies and binding energy calculations three molecules namely zinc85531017, zinc95919096 and zinc33963788 from the natural database were reported as the potential inhibitors for the pancreatic lipase. Among them zinc95919096 presented all the interactions matching to both standard and crystal ligand and hence it can be further proceeded to drug discovery process.