Search

Ganoderma lucidum has been suggested as a natural immunomodulator. It is not yet clear exactly which combination of this extract is responsible for its immunomodulatory effects. Still, it appears that the 3-complement (CR3) receptor on the surface of immune cells acts as a receptor for beta-glucans (glucan-8), which is the main component of this extract. Since glucose-6-phosphate dehydrogenase (G6PD) plays a vital role in regulating macrophage functions, including nitric oxide production, we considered the effect of this extract on viability, G6PD enzyme activity, and nitric oxide (NO) production in peritoneal BALB/c macrophages. First, peritoneal macrophages of BALB/c mice were isolated and treated with concentrations (0.001, 0.01, 0.1, 1, 10, and 100 g/ml) of Ganoderma lucidum polysaccharide extract (GL-PS). After 24 hours of incubation by MTT test, we evaluated the viability of macrophages, and the effective dose was determined to be 0.1g/ml. To determine the specific activity of glucose-6-phosphates, they were incubated with GI-PS for 24 hours at a 0.1 mg/ml dose. Determination of protein concentration was obtained by the Bradford method in cell supernatant extract. Also, after 18 hours of incubation, the amount of nitric oxide (NO) production was measured using Grace colorimetric method. According to the results, a dose of 0.1μg/ml of Ganoderma lucidum polysaccharide extract had the most significant effect on the viability (stimulation coefficient) of peritoneal macrophages compared to other amounts (p0.05). It was also found that a dose of 0.1μg/ml GL-PS increases NO production and the specific activity of the G6PD enzyme (p0.05). Ganoderma lucidum, a medicinal fungus, is widely used in East Asian countries, especially in China, to increase the quality of life and longevity. After this study, we concluded that GL-PS extract has an immunomodulatory effect on macrophage activity. Therefore, the polysaccharide extract of this fungus can be used as a strengthening agent of the phagocytic system against infectious agents and pathogens such as the Leishmania parasite because of the production of nitric oxide by macrophages plays an essential role in defense against them.

A novel UV/moisture dual-curable polyurethane resin has been synthesized via a two-step process. In the first step, methoxysilane-modified polyether polyol (SPOL) was prepared through the thiolene ...

A series of phthalate polyester polyols (PEs) were synthesized via a polycondensation reaction with phthalic anhydride (PA) and different glycols, such as neopentyl glycol (NPG), ethylene glycol (EG), diethylene glycol (DEG), 2-methy-1,3-propanediol (MPO), 1,4-butylene glycol (1,4-BDO) and trimethylolpropane (TMP). Reactive hot melt polyurethane adhesive (HMPUR) with high initial bonding strength was then prepared by poly(propylene glycol) 2000 (PPG-2000), Dynacoll 7360 with these resultant PEs. Effects of different glycols on the glass transition temperature (Tg) and viscosity of the PEs were investigated. Besides, influences of these resultant PEs on the water resistance, bonding strength, thermal stability and surface morphology of the HMPUR were further discussed. The experimental results showed that Tg and viscosity of the PEs decreased with the increase of the chain flexibility of diols. The initial bonding strength of the HMPUR increased with the increase of Tg of the PEs. The hydrogen bond...

The controlling effect of tectonic uplift and denudation on uranium mineralization has been much studied previously, and its important contribution to uranium mineralization has been fully recognized. However, no systematic theory and methodological criteria for uranium prospecting has been summarized. Here we present the results of an in-depth study of the characteristics and formation process of typical sandstone-type uranium deposits in the northern basin of China, and conclude with a uranium metallogenic theory: tectonic uplift and denudation events are the driving force for the formation of sandstone-type uranium deposits (or even mudstone-type uranium deposits). The stage of tectonic uplift and subsequent denudation events since the formation of the target layer determines the mineralization stages: the greater the intensity and duration of uplifting and denudation events, the larger the scale of uranium mineralization. The formation of large and mega-scale sandstone-type uranium deposits requires multiple stages of tectonic uplift and denudation events superimposed in the same direction. Single or polydirectional tectonic uplift and denudation events often do not form industrial uranium deposits. In this paper, a three-step method to predict the occurrence of sandstone-type uranium deposits is established, which includes (1) determining the tectonic framework division of the sedimentary basin being investigated, (2) a burial and denudation history study, and (3) apatite fission-track simulation of the erosion source area. Focusing on the tectonic evolution and the rapid uplift and denudation events of the basin and the erosion source area is critical (the tectonic evolution of the two areas usually is closely coupled). The desired result can be achieved only by combining the aforementioned theory with basic principles of sandstone-type uranium mineralization, and treating uranium mineralization as a result of a special tectonic event. The theory deepens the understanding of sandstone-type uranium mineralization, and the method plays a role in the rapid evaluation of sandstone-type uranium deposits in sedimentary basins, and it can be extended to research and prediction in other basins.

Fluorinated acrylic pressure sensitive adhesive (PSA) latexes based on butyl acrylate (BA), acrylic acid (AA), 2-hydroxyethyl acrylate (HEA) and 2,2,2-trifluoroethyl methacrylate (TFMA) were synthesized via a monomer-starved seeded semi-continuous emulsion polymerization process using a reactive emulsifier. Effects of TFMA on the resultant PSA properties were comprehensively investigated. IR analysis indicated that TFMA can be introduced into the latex particles successfully through emulsion polymerization. Gel content and sol molecular weight of the PSA were not significantly affected by the addition of TFMA. It was also found that T g and thermal stability of the PSA were both improved remarkably as TFMA content increased. Water resistance of the PSA was enhanced, while surface energy of the PSA was decreased with TFMA concentration increased, which were confirmed by XPS analysis. Moreover, the storage modulus (G’) and loss modulus (G”) of the PSA increased with TFMA content. Peel strength of the PSA on PP surface was not affected by the presence of TFMA, while peel strength of the PSA on SS and PC surfaces were first decreased and then increased with the TFMA content. Besides, the influences of reactive surfactant SR-10 and conventional surfactant CO-436 on the acrylic latex PSA were also compared.

Acrylic pressure sensitive adhesive (PSA) latexes were synthesized via a monomer-starved seeded semi-continuous emulsion polymerization process with butyl acrylate (BA), methyl methacrylate (MMA), N,N-dimethylacrylamide (DMA), acrylic acid (AA) and 2-hydroxyethyl acrylate (HEA) as monomers. Impacts of DMA on the resultant latex and PSA properties were comprehensively investigated. Results indicated that latex particle size was independent of the amount of DMA in the pre-emulsion feed with excessive and constant surfactant concentration. Latex viscosity increased with DMA concentration. It was also found that water resistance of acrylic latex PSA became worse by the presence of DMA, confirmed by water contact angle measurements. Besides, DSC results showed that as the amount of DMA increased, glass transition temperatures (Tg) of the polymers were elevated significantly. TGA results showed that thermal stability of PSA was improved with DMA as a co-monomer. Furthermore, as DMA amount increased, gel content slightly increased, while sol molecular weight (Mw, Mn) of the polymer decreased. Finally, with respect to the adhesive properties of the PSA, it was observed that loop tack initially increased and then decreased with the addition of DMA from 0 to 4 wt%, and the maximum value appeared at 1 wt%. Peel strength reduced, while shear strength improved with increased DMA concentration.

Acrylic pressure sensitive adhesive (PSA) latexes were synthesized via a starved monomer-seeded semi-continuous emulsion polymerization process with butyl acrylate (BA), methyl methacrylate, acrylic acid (AA), 2-hydroxyethyl acrylate and trifunctional cross-linker, triallyl isocyanurate (TAIC). Influences of TAIC on the resultant latex and PSA properties were comprehensively investigated. The results indicated that latex particle size was independent of the amount of TAIC in the pre-emulsion feed, while the viscosity of the latex increased remarkably with TAIC content increased. Thermal gravimetric analysis result showed that the thermal stability of the polymers was improved significantly with the addition of TAIC. Besides, with the increase in TAIC content, gel content of the polymer increased significantly, while molecular weight between cross link points (Mc) and sol molecular weight (Mw, Mn) of the polymer decreased remarkably. Moreover, for the cross-linked adhesive film, the shear strength ...

In this work, tert-butyl peroxypivalate initiator was newly used in the solution polymerization of acrylic copolymers with 2-ethylhexyl acrylate, butyl acrylate, methyl methacrylate and acrylic acid monomers for application of pressure-sensitive adhesives (PSAs). Its proper dosage was determined to vary from 0.6 to 1.2 wt % when a high monomer conversion (>99%) was ensured. In this amount range, polymer properties and adhesive performance of the PSAs were investigated. The results indicated that with the amount of tert-butyl peroxypivalate increased, the molecular weights of the polymer decreased and the molecular weight distribution became wider. It was also observed that the synthesized PSAs had high interfacial adhesion and low cohesion strength, and thus exhibited cohesive failure during the peel test. So cross-linking agent was employed to improve the shear strength of the PSAs and to eliminate the adhesive residue while at the sacrifice of loop tack and peel strength. As a whole, the optimal performance was obtained by using 1.2 wt % amount of initiator and 0.5 wt % concentration of cross-linker. In this case, the peel and shear strength have achieved the best balance. In addition, for the cross-linked PSA tapes, the peel strength slightly decreased with the dwell time.

Self-crosslinking fluorinated polyacrylate latexes based on butyl acrylate (BA), fluorine monomer octafluoropentyl methacrylate (OFPMA), self-crosslinking functional monomers acrylic acid (AA) and 2-hydroxyethyl acrylate (HEA) were synthesized by a monomer-starved seeded semi-continuous emulsion polymerization process. The latexes and their corresponding films were characterized by laser particle size analyser, Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), contact angle goniometer, X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). Results indicated that the particle size of the latexes and the gel content of the films were both independent of the amount of OFPMA employed. On the other hand, the particle size of the latexes decreased and the gel content of the films increased with the incorporation of AA and HEA as expected. Glass transition temperature (Tg) and the thermal stability of the copolymer were both improved gradually as OFPMA content increased. XPS, AFM and water contact angle measurement indicated that the fluoroalkyl groups had a tendency to enrich on the surface of the films. However, this enrichment of fluorine on the film surface was reduced after the introduction of self-crosslinking functional monomers into the system. Finally, the adhesive property of the latexes was evaluated for application as a pressure sensitive adhesive (PSA).

Two novel H-shaped chromophores with diallyl groups using 9,10-dihydroanthracene as molecular backbone were synthesised by a six-step reaction including Claisen rearrangement, Rieche formylation reaction and Knoevenagel condensation. Crystal structures of two intermediates 4 and 6 were measured, which demonstrate that the two D–π–A units in a single chromophore molecule are closely arranged in the same direction. Therefore, they will exhibit much higher first molecular hyperpolarisability, which will be used in the preparation of polymeric non-linear optical materials.

Acrylate pressure sensitive adhesive (PSA) latexes were synthesized via a starved monomer seeded semi-batch emulsion polymerization process with butyl acrylate (BA), methyl methacrylate (MMA), acrylic acid (AA) and 2-hydroxyethyl acrylate (HEA). These PSA polymers were then cross-linked with trifunctional propyleneimine external cross-linker (SAC-100) to study the cross-linking reaction between carboxylic group of the polymer chain and cross-linking agent. It was found that cross-linking provided a significant influence on the film formation process based on the result of SEM analysis. In addition, with the increase of SAC-100 content, the gel content of the polymer increased significantly, while molecular weight between cross-link points (Mc) and the sol molecular weight (Mw, Mn) of the polymer decreased remarkably. The TGA result showed that the addition of the external cross-linker can enhance the thermal stability of the latex film. Moreover, for the cross-linked adhesive film, the shear strength was improved greatly while at the sacrifice of loop tack and peel strength, when compared with the uncross-linked counterparts. Besides, dynamic mechanical analysis (DMA) was also used to evaluate the viscoelastic properties of the acrylate emulsion PSA film.

(1R,2R,3S,4R,7R)-7-Isopropyl-6-methylbicyclo[2.2.2]oct-5-ene-2,3-dicarboxylic acid anhydride (tetrahydro-4,7-ethanoisobenzofuran-1,3-dione derivative) adduct 2 was prepared via the isomerization of α-pinene and β-pinene in turpentine followed by the Diels-Alder cycloaddition with maleic anhydride in the presence of phosphoric acid/iodine catalysis. The molecular structure of adduct 2 was characterized by IR, 1H NMR, 13C NMR, 1H-1H COSY, DEPT, HSQC, HMBC, 2D NOESY and MS spectra. The single crystal X-ray crystallographic analysis of adduct 2 was performed, and the X-ray powder diffractive spectrum of the sample adduct 2 is consistent with the diffractive spectrum calculated from the single crystal data. Therefore the structure and stereochemistry of adduct 2 was established based on extensive spectral data and single crystal X-ray analysis.

Dehydroabietylamine derivatives have been reported to eliminate the superoxide anion (O2−˙) and 1,1-dipheny-2-picrylhydrazyl radicals. In this work, several dehydroabietylamine derivatives were shown to have potent anti-oxidative activity in SH-SY5Y cells and exhibited significant inhibition of Aβ42 self-mediated aggregation and the disaggregation of Aβ42 aging fibrils. In particular, the compound 12N,18N-bis(caffeoyl)-14-nitrodehydroabietylamine (3b) showed the most potent inhibitory activity against Aβ42 self-mediated aggregation with an IC50 value of 3.96 ± 0.33 μM. Compound 3b decreased the production of Aβ42 in swAPP HEK293 cells and showed neuroprotective activity against Aβ42-induced cytotoxicity. Through reducing the production of the Aβ42 species, compound 3b alleviated Aβ42-induced paralysis in transgenic Caenorhabditis elegans strain CL4176. Considering its multifunctional activity and low cytotoxicity, 3b is considered to be a potential multifunctional agent for the treatment of Alzheimer's disease.

New metal-free DNA cleaving reagent 1, 1,4,7-triazacrown (TACN) both with aminoethyl, hydroxyethyl side arms and a planar anthraquinone linked by an alkyl (1,6-hexamethylene) spacer has been synthesized and characterized by NMR and MS spectrometry. For comparison, the corresponding aminoethyl, hydroxyethyl triazacrown derivative 2 without the anthraquinone has also been synthesized. DNA-binding properties via fluorescence and CD spectroscopy indicate that the binding affinity of 1 with DNA is much stronger than that of 2. Agarose gel electrophoresis was used to assess plasmid pUC19 DNA cleavage. Kinetic data of DNA cleavage promoted by 1, 2 and parent triazacrown (TACN) 3 under physiological condition give the 15-fold and 234-fold rate acceleration of compound 1 over 2 and parent triazacrown 3. Radical scavenger inhibition study suggests that DNA cleavage promoted by 1 may be a non-oxidative pathway through the transphosphorylation and then hydrolysis. The dramatic rate acceleration is due not only to the anthraquinone moiety of compound 1 intercalating into DNA base pairs via stacking interaction, but also the cooperative catalysis of the nucleophilic hydroxyl and the electrophilic ammonium group for the cleavage of phosphodiester of DNA.

To discover new agents active against methicillin-resistant Staphylococcus aureus (MRSA), in silico models derived from 5451 cell-based anti-MRSA assay data were developed using four machine learning methods, including naïve Bayesian, support vector machine (SVM), recursive partitioning (RP), and k-nearest neighbors (kNN). A total of 876 models have been constructed based on physicochemical descriptors and fingerprints. The overall predictive accuracies of the best models exceeded 80% for both training and test sets. The best model was employed for the virtual screening of anti-MRSA compounds, which were then validated by a cell-based assay using the broth microdilution method with three types of highly resistant MRSA strains (ST239, ST5, and 252). A total of 12 new anti-MRSA agents were confirmed, which had MIC values ranging from 4 to 64 mg/L. This work proves the capacity of combined multiple ligand-based approaches for the discovery of new agents active against MRSA with cell-based assays. We think this work may inspire other lead identification processes when cell-based assay data are available.

Unsaturated carboxylic acids are usually used as functional monomers at low concentrations in emulsion polymerization to improve the colloidal stability and the mechanical properties of the films prepared from the corresponding latexes. These acids are distributed between the aqueous and organic phases to different extents due to their various water solubilities. The partitioning behavior of two new vinyl acids, monobutyl itaconate (MBI) and β-carboxyethyl acrylate (β-CEA), between n-butyl methacrylate (BMA) and the water phases was studied in this work. In addition, the partitioning of commonly used acrylic acid (AA) and methacrylic acid (MAA) was also determined as a benchmark. It was found that the partition coefficients (D) of MBI and β-CEA depended to a large extent on the acid concentration in the total comonomer mixture; the same trends were observed for AA and MAA. With the variation in monomer to water ratio (M/W), the D value of lipophilic acid MBI changed significantly, while for hydrophilic acid β-CEA, the D value changed very little. Furthermore, the values of the partition coefficient of MBI and β-CEA were very strong functions of pH, decreasing rapidly as the pH is increased. On the other hand, temperature has little effect on the partition coefficients for vinyl acids under typical emulsion polymerization reaction conditions. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40868.

Cadherin receptors mediate cell-cell adhesion, signal transduction and assembly of cytoskeletons. How a single transmembrane molecule Cadherin can be involved in multiple functions through modulating its binding activities with many membrane adhesion molecules and cytoskeletal components is an unanswered question which can be elucidated by clues from bead experiments. Human lung cells expressing N-Cadherin were examined. After co-incubation with anti-N-Cadherin monoclonal antibody coated beads, cell surface clustering of N-Cadherin was induced. Immunofluorescent detection demonstrated that in addition to Cadherin, β-Catenin, α-Catenin, α-Actinin and Actin fluorescence also aggregated respectively at the membrane site of bead attachment. Myosin heavy chain (MHC), another major component of Actin cytoskeleton, did not aggregate at the membrane site of bead attachment. Adhesion unrelated protein Con A and polylysine conjugated beads did not induce the clustering of adhesion molecules. It is indicated that the Cadherin/Catenins/α-Actinin/Actin complex is formed at Cadherin mediated cell adherens junction; occupancy and cell surface clustering of Cadherin is crucial for the formation of Cadherin adhesion protein complexes.

Cell-to-cell and cell-to-extracellular matrix (ECM) interactions in the functions of cell adhesion and signal transduction are important in global control of cell phenotypes and cell behavior and are crucial for maintenance of homeostasis and structural/functional stabilization of tissues and organs. Cell adhesion receptors are recognized as the molecular basis of cell adhesion. Cadherin and integrin are widely expressed adhesion receptors in most tissues. They are transmembrane glycoproteins which, through their cytoplasmic domain, bind to many proteins at the inner surface of cell membrane to form molecule-linkage complexes and then connect with the cytoskeleton. Through cell adhesion receptors a network functioning as cell adhesion and signal transduction is organized between tissue cells and cellECM. In this regard cell adhesion receptors play an important role in regulation of morphogenesis, cellcell recognition, cell migration, cell sorting and the determination of cell’s fate in development. They mediate cell functions and their fault expression is intimately correlated with development of disorders like cancer. Several isoforms of lntegrin were found to have tumor suppressor effect. Some components in the molecule-linkage of focal contact are actin-binding proteins as well as substrates of kinase in the lntegrin initiated signal pathway to play a role as signal transducer. Some of these molecules exhibited tumor suppressor effect too. Decreased expression of E-Cadherin has been demonstrated in many epithelium originated carcinomas. Cadherin associated membrane adhesion plaque molecule β-Catenin is also involved in the oncogene Wnt signal pathway. Both E-Cadherin and β-Catenin were proved respectively with tumor suppressor effect against invasiveness and metastasis. That Cadherin is important for the posttranslationally functional expression of Connexin has been supported by evidence from developmental biology and cancer cell differentiation studies to suggest that some sort of interrelation feedback control exists between the two signal pathways.

The difference between human normal and carcinoma lung cells was studied with regard to the protein expression level and localization of the cadherin/catenin/actin complex. Results demonstrated that nod lung cell RF expressed high levels of N-cadherin. β-catenin, α-catenin. These 3 proteins were colocalized at AJs and their submembrane adhesion plaques where they link the Rho-phalloidin-positive actin stress fibers, indicating the existence of N-cadherin/catenin/actin complexes at the AJs Aberrant expression of AJ proteins and the actin cytoskelecton in carcinoma PG cells was observed: (1) inhibition of N-cadherin and to a degree of inhibition of α-catenin protein expression; (2) varied protein modification of β-catenin in cytoplasm soluble fraction and altered distribution of immunofluorescence: majorly in the cytoplasm and minorly on the membrane; (3) disassembly of actin stress fibers and formation of actin bodies in the cytoplasm. The data suggest that inhibited expression of AJ proteins is correlated with the disruption of the AJ complexes and the actin cytoskeleton in carcinoma PG cells, and responsible for its metastasis behaviors.

Gap junctions form intercellular channels for direct exchange of metabolites and second messengers between adjacent cells. The existence of a multi-gene family encoding gap junction proteins, i. e. the connexins (Cx), has been recently demonstrated. Despite the overall sequence homologies and a similar predicted structural motif, their functional properties differ in various tissues. Because of coexpression of two or more connexin proteins in one tissue, determination of properties specific for each connexin is complicated. The regulation of expression of gap junctions and their roles in cellular activities remain mostly unelucidative. Controlled manipulation of connexin molecules in Xenopus oocyte expression system has been use-...

Pressure-sensitive adhesives (PSAs) were produced with latexes synthesized via starved semibatch emulsion polymerization processes with butyl acrylate, three different kinds of hard monomers (styrene (St), methyl methacrylate, and 2-phenoxy ethyl meth- acrylate (SR340)), acrylic acid, and 2-hydroxy ethyl acrylate. The management of both the copolymer composition and the polymer- ization process allowed us to control the behavior of the PSAs. For the acrylate latexes, the types of hard monomers and their contents, the concentration of buffer (bicarbonate (NaHCO3)), and three kinds of semibatch processes were manipulated to modify the polymer properties. The performance of the PSA films cast from these latexes was evaluated by the peel strength. The results show that the PSA prepared with St exhibited the highest peel strength among the three hard monomers, and the latex synthesized by SR340 showed the largest gel content compared with the other two hard monomers. With increasing buffer, the latex particle size increased, and the peel strength initially increased to a maximum and then decreased. Nevertheless, the stability of the latexes decreased with increasing buffer concentration. In addition, the effects of the three kinds of semibatch processes on the peel strength of the PSA were also evaluated. V C 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40095.

The distribution of rDNA was visualized in interphase nuclei of tumor promoter treated human lymphocytes in comparison with the mitogen Phytoheamagglutinin (PHA) effects by using an in situ hybridization fluorescent method. The procedure involves biotinylated rDNA as the probe and FITC-avidin as detection system. Silver (Ag) staining was used to visualize nucleoli. In the interphase nuclei of most of the nonstimulated control lymphocytes, only one small Ag-stained nucleolus could be seen. The in situ hybridization, however, revealed one to several agglomerations of rDNA fluorescent spots. With tumor promoting herb extract WCE (40 µg/ml) or TPA (60 ng/ml) treatment, the interphase nucleoli increased slightly in number with the morphology alteration into larger, reticular or compact granular types. Ag-stained particles also increased in number. The number of the in situ hybridization rDNA fluorescent spots and dots increased markedly and large reticulate formations of numerous rDNA spots were seen. This phenomenum resembles to the changes in PHA stimulated lymphocytes. Statistic analysized data showed signifcant difference between control and drug- treated cells. These results indicate that transcriptionally activated rDNA and amplification of total rDNA was induced by the used tumor promoters.

Cytoskeletal changes in transformed cells (LM-51) exhibiting obviously metastatic capabilities were investigated by utilization of double-fluorescent labelling through combinations of: (1) tubulin indirect immunofluoreseonce plus Rhodamine-phalloidin staining of F-actins; (2) indirect immunofluorescent staining with α-actinin polyclonal- and vinculin monoclonal antibodies. The LM-51 cells which showed metastatic index of >50% were derived from lung metastasis in nude mice after subcutaneous inoculation of human highly metastatic tumor DNA transfected NIH3T3 cell transformants. The parent NIH3T3 cells exhibited well-organized microtubules, prominent stress fibers and adhesion plaques while their transformants showed remarkable eytoskeletal alterations: (l) reduced microtubules but increased MTOC fluorescence; (2) disrupted stress fibers and fewer adheaion plaques with their protein components redistributed in the cytoplasm; (3) F-actin- and α-actinin/vinculin aggregates appeared in the cytoplasm. These aggregates were dot-like, varied in size (0.1–0.4μm) and number, located near the ventral surface of the cells. TPA-induced actin/vineulin bodies were studied too. Indications that aotin and α-actinin/vinoulin redistribution might be important alterations involved in the expression of metastatic capabilities of LM-51 transformed cells were discussed.

Go-localization of microtubnle (MT) and muscle myosin (MHC) myofibril immunofluoreseoneo in developing myotubes of chicken skeletal muscle cultures was observed by using double staining of tubulin and MHC indirect immunofluorescence. 12-o-tetradecanoyl-phorbol-13-acetate (TPA) selectively and reversibly blocks myofibrillogenesis and alters the morphology of myotubes into myosacs where MTs are present in radiating pattern. When the arrested myogenic cells recover and start myofibrillogenesis after released from TPA, prior to the emergence of myofibrils, the pro-existing MTs become bipolarly aligned eoineidontly with the tubular restoration of cell shape. Single nascent myofibrils overlapping with MTs extend into the base of growth tips where MTs go farther to the end of the tips. That MT might act as scaffold in guiding the bipolar elongation of the growing myofibrils was suggested. Taxol and eoleomid disturbed MT polymerization and disposition, and interfered with the normal spatial assembly of myofibrils in developing myotubos.

The correlation between expression of ca(2+)-dependent cell adhesion molecule, cadherin, and gap junctional intercellular communication (GJIC) in human lung carcinoma PG cell line and connexin43 (Cx43) cDNA transfected PG cell clones was investigated. Results from immunoblotting and immunofluorescent staining revealed that cultured normal human lung cells (RF) expressed N-cadherin. However, the expression level of Kcadherin in PG cells was very low in comparison with normal RF cells. The Cx43 transfected PG clones exhibited comparable levels of Cx43 protein, but varied in the level of N-cadherin expression and in the function of GJIC as measured by scrape-loading and dye transfer (SLDT) method. Positive correlation between N-cadherin and GJIC was demonstrated. Thein vitro andin uivo, growth examination results suggest that N-cadherin mediated cell-cell adhesions and Cx43 functional expression, the GJIC, may work coordinately with each other in regulation of cell growth and differentiation. Deficiency in both GJIC and cell adhesion may be crucial for cell transformation.