Molecular characterization and functional analysis of a Flowering locus T homolog gene from a Phalaenopsis orchid

Warm day and cool night conditions significantly induce reproductive spike formation in Phalaenopsis plants; hence, determining the flowering mechanism regulating the reproductive transition is important. Flowering locus T (FT) plays important roles in flowering induction in several plants. To explore spike induction by warm days and cool nights in Phalaenopsis orchids, we isolated the FT (PhFT) from Phalaenopsis hybrid Fortune Saltzman. The cDNA of PhFT was 809-bp long and contained a 531-bp open reading frame encoding a putative protein of 176 amino acids, a 58-bp 5'-untranslated region (UTR), and a 220-bp 3'-UTR. The predicted molecular mass of PhFT was 19.80 kDa, with an isoelectric point of 8.68. The PhFT was predicted to possess the conserved functional regions of the phosphatidylethanolamine-binding protein superfamily. Nucleotide sequence data indicated that PhFT contained 3 introns and 4 exons. Sequence alignment and phylogenetic analyses of PhFT revealed high homology to the FT proteins of Cymbidium goeringii and Oncidium Gower Ramsey. Quantitative real-time polymerase chain reaction analysis indicated that PhFT mRNA was expressed in roots, apical leaves, mature leaves, and flowers. In flowers, PhFT was expressed more in developing floral buds than in mature flowers and was predominantly expressed in ovaries and petals. Ectopic expression of PhFT in Arabidopsis ft-1 mutants showed novel early-flowering phenotypes that lost their siliques. Our results indicated that the ectopic expression of PhFT could partially complement the late flowering defect in transgenic Arabidopsis ft-1 mutants. Our findings suggest that PhFT is a putative FT homolog in Phalaenopsis plants that regulates flowering transition.

A three-dimensional cadmium(II) coordination polymer: poly[[[μ-4,4'-(propane-1,3-diyl)dipyridine-κ(2)N:N](μ-3,3'-thiodipropionato-κ(3)O,O':O)cadmium(II)] monohydrate]

In the title coordination polymer, {[Cd(C6H8O4S)(C13H14N2)]·H2O}n, the Cd(II) atom displays a distorted octahedral coordination, formed by three carboxylate O atoms and one S atom from three different 3,3'-thiodipropionate ligands, and two N atoms from two different 4,4'-(propane-1,3-diyl)dipyridine ligands. The Cd(II) centres are bridged through carboxylate O atoms of 3,3'-thiodipropionate ligands and through N atoms of 4,4'-(propane-1,3-diyl)dipyridine ligands to form two different one-dimensional chains, which intersect to form a two-dimensional layer. These two-dimensional layers are linked by S atoms of 3,3'-thiodipropionate ligands from adjacent layers to form a three-dimensional network.

A novel small molecule aurora kinase inhibitor attenuates breast tumor-initiating cells and overcomes drug resistance

Chemoresistance is a major cause of cancer treatment failure. Tumor-initiating cells (TIC) have attracted a considerable amount of attention due to their role in chemoresistance and tumor recurrence. Here, we evaluated the small molecule Aurora kinase inhibitor AKI603 as a novel agent against TICs in breast cancer. AKI603 significantly inhibited Aurora-A (AurA) kinase and induced cell-cycle arrest. In addition, the intragastric administration of AKI603 reduced xenograft tumor growth. Interestingly, we found that breast cancer cells that were resistant to epirubicin expressed a high level of activated AurA and also have a high CD24(Low)/CD44(High) TIC population. The inhibition of AurA kinase by AKI603 abolished the epirubicin-induced enrichment of TICs. Moreover, AKI603 suppressed the capacity of cells to form mammosphere and also suppressed the expression of self-renewal genes (β-catenin, c-Myc, Sox2, and Oct4). Thus, our work suggests the potential clinical use of the small molecule Aurora kinase inhibitor AKI603 to overcome drug resistance induced by conventional chemotherapeutics in breast cancer.

Androglobin knockdown inhibits growth of glioma cell lines

Globin family was famous for oxygen supply function of its members such as hemoglobin and myoglobin. With the progress of research, several members of this protein family have been proven to play roles in tumors including glioma. Androglobin (ADGB) is a recently identified member of globin family with very few studies about its function. In the present study, we show that ADGB plays an oncogene role in glioma. Lentiviral vector mediated ADGB knockdown inhibited the proliferation of glioma cell lines determined by MTT assay and colony formation assay. ADGB knockdown also increased the apoptosis of glioma cell line U251 assessed by flow cytometry. In addition, western blot showed that ADGB knockdown altered levels of several proteins related to proliferation, survival or apoptosis in U251 cells. These findings suggest ADGB is involved in the progression of glioma in vitro.

Identification of warm day and cool night conditions induced flowering-related genes in a Phalaenopsis orchid hybrid by suppression subtractive hybridization

The influence of warm day and cool night conditions on induction of spikes in Phalaenopsis orchids has been studied with respect to photosynthetic efficiency, metabolic cycles and physiology. However, molecular events involved in spike emergence induced by warm day and cool night conditions are not clearly understood. We examined gene expression induced by warm day and cool night conditions in the Phalaenopsis hybrid Fortune Saltzman through suppression subtractive hybridization, which allowed identification of flowering-related genes in warm day and cool night conditions in spikes and leaves at vegetative phase grown under warm daily temperatures. In total, 450 presumably regulated expressed sequence tags (ESTs) were identified and classified into functional categories, including metabolism, development, transcription factor, signal transduction, transportation, cell defense, and stress. Furthermore, database comparisons revealed a notable number of Phalaenopsis hybrid Fortune Saltzman ESTs that matched genes with unknown function. The expression profiles of 24 genes (from different functional categories) have been confirmed by quantitative real-time PCR in induced spikes and juvenile apical leaves. The results of the real-time PCR showed that, compared to the vegetative apical leaves, the transcripts of genes encoding flowering locus T, AP1, AP2, KNOX1, knotted1-like homeobox protein, R2R3-like MYB, adenosine kinase 2, S-adenosylmethionine synthetase, dihydroflavonol 4-reductase, and naringenin 3-dioxygenase accumulated significantly higher levels, and genes encoding FCA, retrotransposon protein Ty3 and C3HC4-type RING finger protein accumulated remarkably lower levels in spikes of early developmental stages. These results suggested that the genes of two expression changing trends may play positive and negative roles in the early floral transition of Phalaenopsis orchids. In conclusion, spikes induced by warm day and cool night conditions were complex in Phalaenopsis orchids; nevertheless, several molecular flowering pathway-related genes were found. The acquired data form the basis for a molecular understanding of spike induction by warm day and cool night conditions in Phalaenopsis orchids.

Ginsenoside Rg3 inhibits melanoma cell proliferation through down-regulation of histone deacetylase 3 (HDAC3) and increase of p53 acetylation

Malignant melanoma is an aggressive and deadly form of skin cancer, and despite recent advances in available therapies, is still lacking in completely effective treatments. Rg3, a monomer extracted from ginseng roots, has been attempted for the treatment of many cancers. It is reported that the expressions of histone deacetylase 3 (HDAC3) and p53 acetylation correlate with tumor cell growth. However, the antitumor effect of Rg3 on melanoma and the mechanism by which it regulates HDAC3 expression and p53 acetylation remain unknown. We found high expression of HDAC3 in human melanoma tissues to be significantly correlated to lymph node metastasis and clinical stage of disease (p<0.05). In melanoma cells, Rg3 inhibited cell proliferation and induced G0/G1 cell cycle arrest. Rg3 also decreased the expression of HDAC3 and increased the acetylation of p53 on lysine (k373/k382). Moreover, suppression of HDAC3 by either siRNA or a potent HDAC3 inhibitor (MS-275) inhibited cell proliferation, increased p53 acetylation and transcription activity. In A375 melanoma xenograft studies, we demonstrated that Rg3 and HDAC3 short hairpin RNA (shHDAC3) inhibited the growth of xenograft tumors with down-regulation of HDAC3 expression and up-regulation of p53 acetylation. In conclusion, Rg3 has antiproliferative activity against melanoma by decreasing HDAC3 and increasing acetylation of p53 both in vitro and in vivo. Thus, Rg3 serves as a potential therapeutic agent for the treatment of melanoma.

Inhibition of Liver Cancer Cell Proliferation and Migration by a Combination of (-)-Epigallocatechin-3- Gallate and Ascorbic Acid

A mixture of (-)-epigallocatechin-3-gallate (EGCG) and ascorbic acid exhibited 73.2% inhibition of SMMC-7721 cell proliferation in a soft agar colony formation assay, which was much higher than EGCG (40.4%) or ascorbic acid (12.4%) alone. In the cell migration assay, the mixture also significantly suppressed the migration of SMMC-7721 cells by 65.9% while EGCG and/or ascorbic acid did by 28.9% and 18.7%, respectively. Ascorbic acid was able to enhance the antioxidant activity of EGCG by decreasing the intracellular oxidative stress according to fluorographic analysis of oxidative stress. In conclusion, the combination of EGCG and ascorbic acid can strongly suppress the proliferation and metastasis of liver cancer cells, possibly with a mechanism associated with the scavenging of reactive oxygen species. All these events add to our knowledge of liver cancer chemotherapy.

ZFX knockdown inhibits growth and migration of non-small cell lung carcinoma cell line H1299

ZFX (zinc finger transcription factor, X chromosome-linked) contributes to the maintenance of different types of stem cells and the progression of various cancers. We have previously reported that ZFX knockdown inhibits proliferation of glioma in vitro and in vivo. Since overexpression of ZFX in lung cancer tissue correlates with lymph node metastasis, we hypothesized that ZFX may play a role in lung cancer. In this study, we identified ZFX as a promoter of lung cancer growth and migration in a NSCLC (non-small cell lung carcinoma) cell line H1299. ZFX knockdown caused proliferation inhibition determined by MTT assay and colony formation assay, G0/G1 arrest of cell cycle and slightly increased proportion of apoptotic cells assessed by flow cytometry assay, decreased population of migrating cells showed by wound-healing assay, increased cell senescence evidenced by senescence-associated β-galactosidase staining. ZFX knockdown also led to decreased proportion of tumor bearing mice and reduced mean tumor volume in a subcutaneous tumor model. In addition, western blot showed that ZFX knockdown down regulated a set of proteins involved in proliferation, survival and motility. Altogether, these results suggest that ZFX may be a potential therapeutic target for NSCLC.

Poly[μ₇-sulfanediyldiacetato-disilver(I)]

In the title coordination polymer, [Ag₂(C₄H₄O₄S)], each AgI cation is four-coordinated by three of the four carboxylate O atoms and the S atom from symmetry-related sulfanediyldiacetate ligands, thus defining a distorted tetrahedral geometry at the metal centre. The AgI cations are bridged by sulfanediyldiacetate groups, leading to a two-dimensional layer structure. These layers are interconnected via Ag-S bonds to form a three-dimensional coordination polymer network overall.

Deacetylated GM3 promotes uPAR-associated membrane molecular complex to activate p38 MAPK in metastatic melanoma

GM3, the simplest ganglioside, regulates cell proliferation, migration, and invasion by influencing cell signaling at the membrane level. Although the classic N-acetylated form of GM3 (NeuAcLacCer) is commonly expressed and has been well studied, deacetylated GM3 (NeuNH2LacCer, d-GM3) has been poorly investigated, despite its presence in metastatic tumors but not in noninvasive melanomas or benign nevi. We have recently found that d-GM3 stimulates cell migration and invasion by activating urokinase plasminogen activator receptor (uPAR) signaling to augment matrix metalloproteinase-2 (MMP-2) function. However, the mechanisms by which d-GM3/uPAR increase MMP-2 expression and activation are not clear. By modifying the expression of d-GM3 genetically and biochemically, we found that decreasing d-GM3 expression inhibits, whereas overexpressing d-GM3 stimulates, p38 mitogen-activated protein kinase (MAPK) activity to influence MMP-2 expression and activation. p38 MAPK (p38) activation requires the formation of a membrane complex that contains uPAR, caveolin-1, and integrin α5β1 in membrane lipid rafts. In addition, knocking down or inhibiting focal adhesion kinase (FAK), phosphoinositide 3-kinase (PI3K), or Src kinase significantly reduces d-GM3-induced p38 phosphorylation and activation. Taken together, these results suggest that d-GM3 enhances the metastatic phenotype by activating p38 signaling through uPAR/integrin signaling with FAK, PI3K, and Src kinase as intermediates. Elucidation of the mechanisms by which d-GM3, a newly discovered, potential biomarker of metastatic melanomas, promotes cell metastasis will help us to understand the function of d-GM3 in metastatic melanomas and may lead to novel GM3-based cancer therapies.

Fucosyltransferase IV enhances expression of MMP-12 stimulated by EGF via the ERK1/2, p38 and NF-κB pathways in A431 cells

Fucosyltransferase IV (FUT4) has been implicated in cell adhesion, motility, and tumor progression in human epidermoid carcinoma A431 cells. We previously reported that it promotes cell proliferation through the ERK/MAPK and PI3K/Akt signaling pathways; however, the molecular mechanisms underlying FUT4- induced cell invasion remain unknown. In this study we determined the effect of FUT4 on expression of matrix metalloproteinase (MMP)-12 induced by EGF in A431 cells. Treatment with EGF resulted in an alteration of cell morphology and induced an increase in the expression of MMP-12. EGF induced nuclear translocation of nuclear factor κB (NF-κB) and resulted in phosphorylation of IκBα in a time-dependent manner. In addition, ERK1/2 and p38 MAPK were shown to play a crucial role in mediating EGF-induced NF-κB translocation and phosphorylation of IκBα when treated with the MAPK inhibitors, PD98059 and SB203580, which resulted in increased MMP-12 expression. Importantly, we showed that FUT4 up-regulated EGF-induced MMP-12 expression by promoting the phosphorylation of ERK1/2 and p38 MAPK, thereby inducing phosphorylation/ degradation of IκBα, NF-κB activation. Base on our data, we propose that FUT4 up-regulates expression of MMP-12 via a MAPK-NF-κB-dependent mechanism.

Overexpression of fucosyltransferase IV promotes A431 cell proliferation through activating MAPK and PI3K/Akt signaling pathways

Lewis Y (LeY) is a carbohydrate tumor-asssociated antigen. The majority of cancer cells derived from epithelial tissue express LeY type difucosylated oligosaccharide. Fucosyltransferase IV (FUT4) is an essential enzyme that catalyzes the synthesis of LeY oligosaccharide. Our previous studies have shown that FUT4 overexpression promotes A431 cell proliferation, but the mechanism is still largely unknown. Herein, we investigated the role of the mitogen-activated protein kinases (MAPKs) and phosphoinositide-3 kinase (PI3K)/Akt signaling pathways on FUT4-induced cell proliferation. Results show that overexpression of FUT4 increases the phosphorylation of ERK1/2, p38 MAPK, and PI3K/Akt. Inhibitors of PI3K (LY294002 and Wortmannin) prevented the phosphorylation of ERK1/2, p38 MAPK, and Akt PI3K). Moreover, phosphorylation of Akt is abolished by inhibitors of ERK1/2 (PD98059) and p38 MAPK (SB203580). These data suggested that FUT4 not only activates MAPK and PI3K/Akt signals, but also promotes the crosstalk among these signaling pathways. In addition, FUT4-induced stimulation of cell proliferation correlates with increased cell cycle progression by promoting cells into S-phase. The mechanism involves in increased expression of cyclin D1, cyclin E, CDK 2, CDK 4, and pRb, and decreased level of cyclin-dependent kinases inhibitors p21 and p27, which are blocked by the inhibitors of upstream signal molecules, MAPK and PI3K/Akt. In conclusion, these studies suggest that FUT4 regulates A431 cell growth through controlling cell cycle progression via MAPK and PI3K/Akt signaling pathways.

Tuberculosis of the breast: 10 years' experience in one institution

SETTING

Breast tuberculosis (TB) is rare even in endemic areas. Its presentation is variable and non-specific, and its diagnosis is therefore usually delayed.

DESIGN

We recruited breast TB cases between 1998 and June 2009 at Kaohsiung Medical Center in southern Taiwan. We retrospectively reviewed the clinical features, diagnosis and management of breast TB.

RESULTS

A total of 26 patients with breast TB (25 females) were included in this study. The most common presentation was breast tumour, followed by breast abscess and painful sensation. Patients received partial mastectomy or incision and drainage. The pathological examination revealed granulomatous inflammation, acute and chronic inflammation or both. Polymerase chain reaction has very low sensitivity in diagnosing breast TB. The interval between initial presentation and definite treatment was an average of 54.5 days. All patients received anti-tuberculosis chemotherapy, with excellent response.

CONCLUSION

The presentation of breast TB is variable and diagnosis is usually delayed. The disease can be diagnosed through pathological tests and a high suspicion by experienced physicians. The definite treatment is adequate anti-tuberculosis chemotherapy after surgical excision or drainage.

De-N-acetyl GM3 promotes melanoma cell migration and invasion through urokinase plasminogen activator receptor signaling-dependent MMP-2 activation

We have recently discovered that de-N-acetyl GM3 [NeuNH(2)LacCer, d-GM3], a derivative of ganglioside GM3, is specifically expressed in metastatic tumor cells and that its expression correlates with an enhanced metastatic phenotype. Although the classic N-acetylated form of GM3 (NeuAcLacCer, c-GM3) is found in both normal and tumor cells, metastatic tumor cells (but not other cells) predominantly express d-GM3 (82-95% of total GM3). d-GM3 expression is mainly found in metastatic melanomas, but not in benign nevi or the majority of primary melanomas. Using metastatic (d-GM3-positive) and poorly invasive (d-GM3-negative) human melanoma cell lines, we found that d-GM3 stimulates cell migration and invasion by increasing the expression and activation of urokinase-like plasminogen activator (uPA). Further studies showed that d-GM3 activates matrix metalloproteinase-2 (MMP-2), but not MMP-9, when uPA receptor signaling is activated. These results implicate d-GM3 as a specific marker for metastatic melanoma and a novel therapeutic target for neoplastic diseases.

Stability of hydrophilic magnetic nanoparticles under biologically relevant conditions

Hydrophilic 2,3-dimercaptosuccinnic acid (HOOC-CH(SH)-CH(SH)-COOH, DMSA) coated monodisperse magnetic nanoparticles (Fe3O4) were dispersed in water, RPMI-1640 with 10% (v/v) fetal calf serum, RPMI-1640, PBS and MES, respectively, to investigate their stability under biologically relevant conditions. The Photon Correlation Spectroscopy (PCS) results showed that DMSA-Fe3O4 nanoparticles existed as aggregate under biological conditions. UV-vis, MRI and AFM results indicated that DMSA-Fe3O4 nanoparticles dispersed in RPMI-1640, PBS and MES presented poor stability, whereas those dispersed in RPMI-1640 with fetal calf serum exhibited excellent stability, which was due to their adsorption from fetal calf serum, as confirmed by zeta potential and IR results. Additionally, in vitro cell experiments showed that DMSA-Fe3O4 nanoparticles with adsorption from fetal calf serum had higher intracellular uptake than those without adsorption from serum, indicating that fetal calf serum could play a great role in intracellular uptake of nanoparticles.

Tetra-aqua-(1,10-phenanthroline-κN,N')magnesium(II) bis-[(2,4-dichloro-phen-yl)acetate]

In the mononuclear title complex, [Mg(C(12)H(8)N(2))(H(2)O)(4)](C(8)H(5)Cl(2)O(2))(2), each Mg(II) ion is hexa-coordinated by two N atoms from a 1,10-phenanthroline ligand [Mg-N = 2.233 (2) Å] and four water mol-ecules [Mg-OW = 2.033 (2) and 2.043 (1) Å] in a distorted octa-hedral geometry. A twofold rotation axis passes through the Mg atom. In the crystal structure, the cations and anions are linked by inter-molecular O-H⋯O hydrogen bonds and π-π stacking inter-actions [centroid-centroid distance = 3.804 (2) Å] into layers parallel to the ac plane.

Poly[bis(μ2-benzyloxyacetato-κ3O,O′:O′′)cadmium(II)]

The title cadmium derivative of benzyl­oxyacetic acid, [Cd(C₉H₉O₃)₂]_n, exists as a μ₂-carboxyl­ate-bridged layer network. Two benzyl­oxyacetate units each chelate the metal through a carboxylate as well as through the ether O atoms; the metal is also coordinated by the double-bond carbonyl O atom of two adjacent benzyl­oxyacetate units in an octa­hedral geometry. The metal atom lies on a special position of 2 site symmetry. The phenyl group is disordered equally over two positions.

catena-Poly[[[diaquabis(1H-indole-3-acetato-κO)cobalt(II)]-μ-4,4′-bipyridine-κ2N:N′] tetrahydrate]

The 4,4′-bipyridine spacer in the title compound, [Co(C₁₀H₈NO₂)₂(C₁₀H₈N₂)(H₂O)₂]·4H₂O, links the diaqua­cobalt(II) dicarboxyl­ate units into a linear chain; the metal atom lies on a center of inversion in an octa­hedral environment. The coordinated and uncoordinated water mol­ecules inter­act through O—H⋯O hydrogen bonds to form a three-dimensional network.

[Phase III clinical study of zoledronic acid in the treatment of pain induced by bone metastasis from solid tumor or multiple myeloma]

OBJECTIVE

To evaluate the efficacy and safety of zoledronic acid in the treatment of bone pain in patients with bone metastasis from solid tumor or multiple myeloma.

METHODS

A randomized, double-blind, double-simulated and multi-center phase III clinical trail with pamidronate as control was conducted. Patients with moderate to severe bone pain (VAS > 50 mm) induced by solid tumor or multiple myeloma were randomized to receive intravenous zoledronic acid 4 mg or pamidronate 90 mg. Then the change of VAS and urinary NTX/Cr and CTX/Cr were observed in two groups.

RESULTS

From July 2005 to September 2006, 228 patients with bone pain induced by bone metastasis from 15 cancer centers were randomize into two groups: 116 patients in zoledronic acid group and 112 patients in pamidronate group. The VAS value was decreased gradually after treatment in these two groups. Significant improvement in bone pain after treatment were observed both in zoledronic acid group and the control group when compared with baseline VAS on D8 (-11.77% vs. -10.87%), D15 (-24.60% vs. -21.06%) and D28 (-32.37% vs. -31.26%) (P< or =0.0001), but no significant difference existed between two groups (P =0.6587). Compared with baseline, urine NTX/Cr and CTX/Cr level were decreased rapidly after treatment in both groups, the nadir was on D8, the median decreased on D28, which was -36.9% vs. -32.1% for NTX/Cr (P = 0.7922) and -63.2% vs. -47.9% for CTX/Cr (P =0.834). The frequently observed adverse events were pyrexia (19.0% vs. 31.3%), vomiting (6.0% vs. 8.9%), nausea (4.3% vs. 4.5%), fatigue (3.4% vs. 2.7%) and constipation (2.6% vs. 1.8%) in the two groups. Compared with baseline, the serum creatinine level was not significantly increased throughout the study.

CONCLUSION

Intravenous injection of 4 mg zoledronic acid can significantly reduce bone pain and bone resorption marker in urine in the Chinese patients with bone metastasis from solid tumor or multiple myeloma, which is tolerable and also comparable to pamidronate in the efficacy and safety.

Synthesis and field electron emission properties of hybrid carbon nanotubes and nanoparticles

Hybrid ZnO-carbon nanotubes as well as nanodiamond-carbon nanotubes were synthesized via a straightforward process of plasma enhanced chemical vapor deposition. For the former, ZnO nanoparticles were instantly coated on the tube surface in the final growing process of carbon nanotubes, while for the latter diamond nanoparticles were grown using pretreatment of a silicon substrate with Ni(NO(3))(2)·6H(2)O/Mg(NO(3))(2)·6H(2)O alcohol solution prior to deposition and a high H(2)/CH(4) gas flow ratio in the deposition process. The morphology and microstructure of the obtained hybrid materials were characterized by transmission electron microscopy. Both hybrid ZnO-carbon nanotubes and nanodiamond-carbon nanotubes exhibited excellent field emission properties.

Suppression of epidermal growth factor receptor signaling by protein kinase C-alpha activation requires CD82, caveolin-1, and ganglioside

Activation of protein kinase C (PKC)-alpha decreases normal and neoplastic cell proliferation by inhibiting epidermal growth factor receptor (EGFR)-related signaling. The molecular interactions upstream to PKC-alpha that influence its suppression of EGFR, however, are poorly understood. We have found that caveolin-1, tetraspanin CD82, and ganglioside GM3 enable the association of EGFR with PKC-alpha, ultimately leading to inhibition of EGFR signaling. GM3- and CD82-induced inhibition of EGFR signaling requires PKC-alpha translocation and serine/threonine phosphorylation, which eventually triggers EGFR Thr654 phosphorylation and receptor internalization. Within this ordered complex of signaling molecules, the ability of CD82 to associate with PKC-alpha requires the presence of caveolin-1, whereas the interaction of caveolin-1 or PKC-alpha with EGFR requires the presence of CD82 and ganglioside GM3. Disruption of the membrane with methyl-beta-cyclodextrin dissociates the EGFR/GM3/caveolin-1/CD82/PKC-alpha complex and prevents the inhibitory effect of PKC-alpha on EGFR phosphorylation, suggesting that caveolin-1, CD82, and ganglioside interact with EGFR and PKC-alpha within intact cholesterol-enriched membrane microdomains. Given the role of these membrane molecules in suppressing EGFR signaling, up-regulation of GM3, caveolin-1, and CD82 function may be an effective adjunctive therapy for treating epithelial cell malignancies.

PDFfit2 and PDFgui: computer programs for studying nanostructure in crystals

PDFfit2 is a program as well as a library for real-space refinement of crystal structures. It is capable of fitting a theoretical three-dimensional (3D) structure to atomic pair distribution function data and is ideal for nanoscale investigations. The fit system accounts for lattice constants, atomic positions and anisotropic atomic displacement parameters, correlated atomic motion, and experimental factors that may affect the data. The atomic positions and thermal coefficients can be constrained to follow the symmetry requirements of an arbitrary space group. The PDFfit2 engine is written in C++ and is accessible via Python, allowing it to inter-operate with other Python programs. PDFgui is a graphical interface built on the PDFfit2 engine. PDFgui organizes fits and simplifies many data analysis tasks, such as configuring and plotting multiple fits. PDFfit2 and PDFgui are freely available via the Internet.

Out-of-plane temperature-dependent resistivity studies on Tl-based superconductors

Temperature-dependent resistivities in the ab-plane and c-axis of Tl-based cuprates have been measured. Unlike the ab-plane properties, which are metallic, c-axis transport is semiconductor-like in the normal state for Tl(2)Ba(2)Ca(2)Cu(3)O(x) (Tl-2223) and Tl(2)Ba(2)CaCu(2)O(x) (Tl-2212). In contrast, for Tl(2)Ba(2)CuO(x) (Tl-2201), transport is metal-like in both the in-plane and the c-axis. For multi-layered cuprates, transport properties along the c-axis could be described by a tunnelling model, whereas for single-layered compound Tl-2201 it would be easier for the out-of-plane transport behaviour to be coherent since the there are no insulating Ca layers in its structure. Moreover, combining the studies on Bi-2201, which has an insulating behaviour for the out-of-plane resistivity, we suggest that the Tl-O layers in Tl-based superconductors could be conducting, unlike the weakly correlated Bi-O layers in Bi-based cuprates.