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Head and neck/oral cancer (HNOC) is a devastating disease. Despite advances in diagnosis and treatment, mortality rates have not improved significantly over the past three decades. Improvement in patient survival requires a better understanding of the disease progression so that HNOC can be detected early in the disease process and targeted therapeutic interventions can be deployed. Accumulating evidence suggests that microRNAs play important roles in many human cancers. They are pivotal regulators of diverse cellular processes including proliferation, differentiation, apoptosis, survival, motility, and morphogenesis. MicroRNA expression patterns may become powerful biomarkers for diagnosis and prognosis of HNOC. In addition, microRNA therapy could be a novel strategy for HNOC prevention and therapeutics. Recent advances in microRNA expression profiling have led to a better understanding of the cancer pathogenesis. In this review, we will survey recent technological advances in microRNA profiling and their applications in defining microRNA markers/targets for cancer prediction, diagnostics, treatment, and prognostics. MicroRNA alterations that consistently identified in HNOC will be discussed, such as upregulation of miR-21, miR-31, miR-155, and downregulation of miR-26b, miR-107, miR-133b, miR-138, and miR-139.

CdSexSy nanocrystals were synthesized in eight solvents that have different coordinating properties, trioctylphosphine oxide, trioctylphosphine, triphenylphosphine, oleylamine, hexadecylamine, dioctylamine, trioctylamine, and 1-octadecene at 230−300 °C. These nanocrystals exhibited high photoluminescence, which could be tuned over most of the visible region by changing the Se/S ratio or the solvent. The nanocrystals were characterized using UV−vis and IR spectroscopy, TEM, EDS, XRD, and NMR. 31P NMR and IR studies provided vital information about the nanocrystal surface capping ligands, indicating that those prepared in noncoordinating solvents were stabilized in solution mainly by oleic acid while those prepared in the coordinating solvents were stabilized mainly by solvent, phosphine and phosphine sulfide ligands, and some oleic acid. The hexagonal or cubic phase of these nanocrystals can be selectively prepared at temperatures as high as 300 °C by choosing the appropriate solvent.

This work presents the successful noncovalent attachment of ∼5 nm diameter cadmium-sulfur-selenium (CdSSe) quantum dots on strips of anatase TiO 2 nanobelts. The TiO 2 nanobelts were hydrothermally synthesized from a strong alkaline solution and subsequently heat-treated to achieve the anatase phase. The self-assembled-monolayer (SAM) technique was employed to attach the quantum dots onto the nanobelts. Due to the hydrophobic nature of the quantum dots, the surface of the nanobelts was first self-assembled with a layer of hydrophobic organic layer before both mixtures were added together. The resulting nanostructure assembly and composition was confirmed via transmission-electron-microscopy (TEM) imaging, Raman spectroscopy, UV-visible absorption spectroscopy (UV-vis), and X-ray photoelectron spectroscopy (XPS). Both Raman and UV-vis spectroscopies indicate evidence of interactions between the quantum dots and nanobelts. The visible-light sensitizing effect of the quantum dots was demonstrated in photocurrent experiments.

Thermal oxidation of a silicon-on-insulator substrate produces evidence that an ordered SiO2 structure can exist on thermally oxidized SiO2–Si interfaces. An apparently ordered SiO2 layer was observed by a high-resolution transmission electron microscope (HRTEM) when a thin silicon layer enclosed by SiO2 was less than 3.0nm thick. X-ray diffraction of the ultrathin Si (

Microarrays are becoming the platform of choice for the analysis of complex genomes, transcriptomes and proteomes. For a number of applications, however, sample or analyte abundance constraints limit the usefulness of microarrays. Rolling circle amplification (RCA) has previously been shown to be a signal amplification method that is useful in these applications on glass microarrays. This report describes use of RCA for multiplexed detection of nucleic acids and proteins on 3-dimensional, porous microarrays (CodeLink™). Assays combined a sandwiched immunoassay with RCA signal amplification of associated haptens, achieving sensitivities of 0.1 pg/ml for IL6, IL8, MIP-1β, and EGF. A similar RCA strategy was utilized in a genotyping assay on CodeLink™ microarrays that provided three-log enhancement of signal intensity. RCA assays on CodeLink™ microarrays were rapid, and utilized low-volumes, suggesting that performance of RCA universal signal amplification on CodeLink™ microarrays may find useful applications in multiplexed measurements, rare biomolecule detection, and small sample analysis.

Aluminium-doped zinc oxide (ZnO:Al) films were deposited by RF magnetron sputtering on single-crystal n-Si substrates to form ZnO:Al/n-Si heterojunctions. The structure of the ZnO:Al films was analysed by X-ray diffraction spectroscopy and scanning electron microscopy. The structural properties of the ZnO:Al/n-Si junction were studied by transmission electron microscopy. The electrical junction properties were characterised by current–voltage (I–V) and capacitance–voltage (C–V) methods. The conductance measured shows a room-temperature turn-on voltage of 0.2–0.4 V. The ideality factor and the junction built-in potential deduced from I–V and C–V plots are 1.62 and 0.56 V at room temperature, respectively. Temperature-dependent dark forward current vs. voltage measurements suggest that trap-assisted multistep tunnelling is the dominant carrier transport mechanism in this heterojunction.

Quantum wells (QWs) consisting of Si and Si-related materials (such as SiO 2 ) are of interest for solar cell work because they can possibly be used as a surface passivating antireflection (AR) coating or as the top cell in an all-silicon tandem solar cell. In this study, we fabricate SiO 2 /Si/SiO 2 QW layers by RF magnetron sputtering and thermal oxidation. On high-resistivity (300 Ω cm) n-type silicon wafer substrates, the effective surface recombination velocity provided by our SiO 2 /Si/SiO 2 QWs is around 4 cm/s for 13 A Si thickness and 480 cm/s for 150 A Si thickness. The parasitic optical absorption in the well-passivating QWs is negligible for terrestrial photovoltaic applications. However, they have very poor AR properties on Si wafers and hence would have to be covered by an additional reflection reducing dielectric film.

The structural, electrical and optical properties of ZnO:Al films prepared by rf magnetron sputtering have been characterised. At substrate temperature of 250 °C and rf power of 100 W, Ar gas pressure is changed from 0.2 to 3.2 Pa to optimise the properties of ZnO:Al films for solar cell application. The X-ray diffraction (XRD) studies show that the films are highly oriented with their crystallographic c-axis perpendicular to the substrate almost independent on Ar pressure. Measurements of transmission spectra reveal that ZnO:Al films have an average transmission of over 83% in visible wavelength range, slightly depending on Ar pressure. The roughness and morphology of films are very sensitive to change of Ar pressure and microstructure is in agreement with the trend given by Thornton’s structure zone model. Furthermore, the use of optimum ZnO:Al film as a window layer and heterojunction partner in ZnO:Al/n-Si heterojunction solar cells has been explored. The best cell exhibits a stable conversion efficiency of 8.2%.

Elucidation of the genetic basis of complex traits and diseases in humans includes the use of genome-wide association studies that depend on the analysis of a large number of diallelic markers. We describe the application of the amplified fragment length polymorphism (AFLP) technique as an efficient approach for rapidly identifying and scoring multiple variants in the human genome. Using a commercially available kit, we found that AFLP yields reproducible DNA fingerprints consisting of 42-132 fragments, 8% of which show variability between individuals. These variant markers appear to be from different chromosomes, and the majority of them is diallelic. Based on the information obtained in this study, it is possible to approximate the minimum number of selective AFLP primer combinations needed to approach a desired coverage density of all chromosomes. To our knowledge, this is the first study showing the general applicability of AFLP in humans and providing a constructive guide for the design of genomic studies in Homo sapiens with this robust methodology.

Different isoenzymes of pyruvate dehydrogenase kinase (PDK) inhibit the mitochondrial pyruvate dehydrogenase complex by phosphorylation of the E1α subunit, thus contributing to the regulation of glucose metabolism. By positional cloning in the 7q21.3-q22.1 region linked with insulin resistance and non-insulin-dependent diabetes mellitus in the Pima Indians, we identified a gene encoding an additional human PDK isoform, as evidenced by its amino acid sequence identity (>65%) with other mammalian PDKs, and confirmed by biochemical analyses of the recombinant protein. We performed detailed comparative analyses of the gene, termed PDK4, in insulin-resistant and insulin-sensitive Pima Indians, and detected five DNA variants with comparable frequencies in both subject groups. Using quantitative reverse transcription polymerase chain reaction, we found that the variants identified in the promoter and 5′-untranslated region did not correlate with differences in mRNA level in skeletal muscle and adipose tissue. We conclude that alterations in PDK4 are unlikely to be the molecular basis underlying the observed linkage at 7q21.3-q22.1 in the Pima Indians. Information about the genomic organization and promoter sequences of PDK4 will be useful in studies of other members of this family of mitochondrial protein kinases that are important for the regulation of glucose metabolism.

Crystalline silicon single quantum wells (QWs) were fabricated by high-temperature thermal oxidation of ELTRAN® (Epitaxial Layer TRANsfer) silicon-on-insulator (SOI) wafers. The Si layer thicknesses enclosed by thermal SiO2 range from 0.8 to 5 nm. Luminescence energies from such QWs vary from 1.77 to 1.35 eV depending on the Si layer thickness, without evidence for interface-mediated transition seen in earlier work. The ability to detect quantum-confined luminescence seems to arise from the use of ELTRAN SOI wafers, from suppressed interface state luminescence by high-temperature oxidation and, possibly, from interface matching by crystalline silicon oxide.

To compare landmark vs surface-shape measurements in a sample of patients with cleft lips and palates following secondary alveolar bone grafting.The faces of 10 patients (4 males and 6 females) with an unilateral cleft lip and palate were captured using a 3D surface camera system before and 6 weeks after alveolar bone grafting. In each face, six coordinates were registered. The pre- and postoperative images were superimposed on areas that were not affected by the surgery. Using 3D modeling software landmarks, nasal symmetry, and surface-to-surface deviation, analysis was performed. All data were subjected to standard statistical analyses.Color map surface-to-surface comparison revealed a significant anteroposterior elevation in the nasal region of the cleft side after surgery.The ala, alar base, and paranasal areas are increased anteroposteriorly after secondary bone grafting. This surgery tends to diminish the asymmetry in nasal morphology typically seen in patients with unilateral cleft lip and palate. Overall, 3D surface-to-surface analysis allows for a better quantification of treatment changes.

Due to the complexity of the dental models in semantics of both shape and form, a fully automated method for the separation of the lower and upper teeth is unsuitable while manual segmentation requires painstakingly user interventions. In this paper, we present a novel interactive method to segment the upper and lower teeth. The process is performed on 3D triangular mesh of the skull and consists of four main steps: reconstruction of 3D model from teeth CT images, curvature estimation, interactive segmentation path planning using the shortest path finding algorithm, and performing actual geometric cut on 3D models using a graph cut algorithm. The accuracy and efficiency of our method were experimentally validated via comparisons with ground truth (manual segmentation) as well as the state of art interactive mesh segmentation algorithms. We show the presented scheme can dramatically save manual effort for users while retaining an acceptable quality (with an averaged 0.29 mm discrepancy from the ideal segmentation).

Multidrug resistance-associated protein (MRP-1/ABCC1) transports a wide range of therapeutic agents and may play a critical role in the development of multidrug resistance (MDR) in tumor cells. However, the regulation of MRP-1 remains controversial. To explore whether miRNAs are involved in the regulation of MRP-1 expression and modulate the sensitivity of tumor cells to chemotherapeutic agents, we analyzed miRNA expression levels in VP-16-resistant MDR cell line, MCF-7/VP, in comparison with its parent cell line, MCF-7, using a miRNA microarray. MCF-7/VP overexpressed MRP-1 mRNA and protein not MDR-1 and BCRP. miR-326 was downregulated in MCF-7/VP compared to MCF-7. Additionally, miR-326 was downregulated in a panel of advanced breast cancer tissues and consistent reversely with expression levels of MRP-1. Furthermore, the elevated levels of miR-326 in the mimics-transfected VP-16-resistant cell line, MCF-7/VP, downregulated MRP-1 expression and sensitized these cells to VP-16 and doxorubicin. These findings demonstrate for the first time the involvement of miRNAs in multidrug resistance mediated by MRP-1 and suggest that miR-326 may be an efficient agent for preventing and reversing MDR in tumor cells.

In this paper, we propose a Mix-resolution Bone-related Statistical Deformable Model (mBr-SDM) to improve the predicting accuracy of orthognathic surgery, particularly for the main deformation region. Mix-resolution Br-SDM consists of two separate Br-SDM of different resolutions: a high-resolution Br-SDM which is trained with more samples to capture the detail deforming variations in the main deforming regions of interest, together with a low-resolution Br-SDM which is trained with a smaller number of samples to capture the major variations of the remaining facial points. The experiments have shown that the mix-resolution Br-SDM is able to significantly reduce the predicting error compared with the corresponding Finite Element Model, while giving a low computational cost which is characteristic of the SDM approach.

Thermal oxidation of a silicon-on-insulator (SOI) substrate gives evidence that an ordered silicon oxide structure exists on the upper, thermally oxidised SiO/sub 2/-Si interface. The ordered structure of silicon oxide was observed by transmission electron microscopy (TEM) in samples of thin monocrystalline Si film less than 3 nm thick encased by thermal SiO/sub 2/. Based on TEM measurement, the ordered silicon oxide has 1.9 A/spl ring/ spacing along the [110] direction of the Si structure and 17 A/spl ring/ thickness along the (100) direction of the Si structure. Its existence may be related to the fact that the silicon layers were very thin, which may have influenced factors such as their pliancy, since ordered oxide phases were not observed on our samples with silicon layers thicker than 3 nm.

Changes in the upper airway after surgical correction of Class III skeletal dentofacial deformity were investigated by measurement of the cephalometric radiographs of 70 Class III subjects before surgery and 6 months after surgery. Comparison of the results with those of a normal group of 74 subjects without deformity or surgery was also carried out. Gender dimorphism in measurements and type of surgery performed were taken into account. Results showed that postoperatively the soft palate and hyoid bone were posteriorly displaced in men, the oropharyngeal, hypopharyngeal, and minimal airway depth were reduced, but in women, the minimal depth was not reduced. In the mandibular setback group, men showed posterior movement of the tongue base, with decrease in minimal airway depth. In the maxillary advancement group, nasopharyngeal depth increased in both genders. In the bimaxillary surgery group, the soft palate moved posteriorly and the tongue occupied a larger proportion of the airway in both genders. The hyoid was displaced backwards in women, while men showed a decrease in both oropharyngeal and minimal airway depth. In comparison with normal subjects, postoperative measurements indicated that the soft palate was reduced in length, thickness, and area, and the base of the tongue was more posterior. Minimal pharyngeal depth was reduced in both genders. After mandibular setback, the tongue base was more posterior and the hypopharyngeal depth was reduced. The bimaxillary surgery group also demonstrated a more posterior tongue base but without reduction of the hypopharyngeal depth. The mandibular setback group should be most at risk of obstructive sleep apnea, but compensatory changes in soft palate morphology may explain the low occurrence in practice.

We have previously described a polymorphism in the 3′ untranslated region (UTR) of the PPP1R3 gene that encodes the muscle-specific glycogen-targeting regulatory PP1 subunit. This polymorphism alters the distance between two putative mRNA-destabilizing ATTTA (AUUUA) motifs and is distinguished by a 10-nucleotide (allele ARE1) vs a 2-nucleotide interval (allele ARE2). ARE2 is associated with insulin resistance as well as increased prevalence of type 2 diabetes in the Pima Indians, and correlates with reduced expression of this subunit in vivo, causing a 10-fold half-life reduction of reporter mRNA in NIH3T3 cells. Gel shift assays, Northwestern blotting, and RNA–protein UV crosslinking revealed three proteins (43, 80, and 139 kDa) binding to the polymorphic ARE region in these cells. The interactions are sequence specific, and can be suppressed by an unlabeled competitor in a dose-dependent manner. The less stable ARE2 allele shows at least 2-fold higher relative protein binding, indicating that the polymorphic ARE region has a mRNA-destabilizing role. We suggest that the increased protein binding to ARE2 contributes to a faster degradation of PPP1R3 mRNA carrying this allele, and the resulting lower concentration of the protein contributes to insulin resistance, thus increasing the risk for development of type 2 diabetes.

Cytoplasmic dynein is a large multisubunit microtubule-based motor protein, which mediates movement of numerous intracellular organelles. We report here the identification of the human homologue of cytoplasmic dynein intermediate chain 1 gene (DNCI1) located on human chromosome 7q21.3-q22.1. The mouse orthologue (Dnci1) was identified along with another highly related gene, Dnci2, and their RNA in situ expression patterns were examined during mouse embryogenesis. Dnci1 was found to have a highly restricted expression domain in the developing forebrain as well as the peripheral nervous system (PNS), while Dnci2 displayed a broad expression profile throughout the entire central nervous system and most of the PNS. A dynamic expression profile was also found for Dnci2 in the developing mouse limb bud. The data presented here provide a framework for the further analysis of the functional role of Dnci1 and Dnci2 in mouse and DNCI1 in human.

Selected candidate genes have been analyzed in the Pima Indians of Arizona based on evidence that insulin resistance and type 2 diabetes have significant genetic determinants. An amino acid substitution at codon 905 of the glycogen-targeting subunit of type 1 protein phosphatase that regulates skeletal muscle glycogenesis was recently reported to be associated with changes in insulin action in Danish subjects. In addition to the variant at 905, we report here a novel substitution at codon 883 and common variant of an "ATTTA" element in the 3'-untranslated region (UTR) of the corresponding gene (PPP1R3). The 3'-UTR variant resembled the mRNA-destabilizing AT(AU)-rich elements (AREs) and resulted in a 10-fold difference in reporter mRNA half-life, was correlated with PPP1R3 transcript and protein concentrations in vivo, and was associated with insulin resistance and type 2 diabetes in the Pimas. The variant is more common in Pimas (0.56) than in Caucasians (0.40). Because of its apparent effect on expression of PPP1R3, it may, in part, contribute to the higher prevalence of type 2 diabetes in this Native American population.

The present invention provides methods for detecting nucleic acid mutations and genetic polymorphisms by single base extension analysis. Specifically, the invention provides an apparatus and methods for the detection of single base extension of a particular oligonucleotide in an oligonucleotide microarray following hybridization between oligonucleotides bound to defined regions of a polymeric hydrogel-based microarray and nucleic acids in a biological sample.

A comparative study of aluminium-doped zinc oxide (ZnO:Al) films deposited by rf magnetron sputtering at room temperature on Si and glass has been performed. In these experiments, two types of substrates (Si wafer and glass) and two Ar pressures (0.31 and 3.23 Pa) were used. The structural and optical characteristics of the ZnO:Al films grown on Si and glass substrates were examined by X-ray diffraction (XRD), scanning electron microscopy (SEM), and double-beam spectrophotometry. The XRD patterns show that, on both substrates, the ZnO films have a dominant [002] peak. The SEM investigation of the film surfaces revealed that the microstructure depends strongly on the substrate type. Transmission measurements showed that, for visible wavelengths, the ZnO films on glass have an average transmission of over 84%, independent of the Ar pressure. The direct optical bandgap of ZnO:Al is 3.31 and 3.34 eV, respectively, for Ar pressures of 0.31 and 3.23 Pa. Furthermore, to evaluate the films' photovoltaic characteristics, ZnO:Al/n-Si heterojunction solar cells were fabricated by sputtering ZnO:Al films at room temperature onto n-Si wafers. The fill factor of the cells was lower than that obtained at 250/spl deg/C substrate temperature, which is due to the relatively high sheet resistance of ZnO:Al films deposited at room temperature.