ΔNp73 and its effector targets promote colorectal peritoneal carcinosis and predict survival.

Peritoneal metastasis of colorectal origin appears in ~10-15% of patients at the time of diagnosis and in 30-40% of cases with disease progression. Locoregional spread through the peritoneum is considered stage IVc and is associated with a poor prognosis. The development of a regional therapeutic strategy based on cytoreductive surgery, and hyperthermic intra-abdominal chemotherapy has significantly altered the course of the disease. Although recent evidence supports the benefits of cytoreductive surgery, the benefits of hyperthermic intra-abdominal chemotherapy are, however, still a matter of debate. Understanding the molecular alterations underlying the disease is crucial for developing new therapeutic strategies. Here, we evaluated the involvement in peritoneal dissemination of the oncogenic isoform of TP73, ΔNp73, and its effector targets in in vitro and mouse models, and in 30 patients diagnosed with colorectal peritoneal metastasis. In an orthotopic mouse model, we observed that tumor cells overexpressing ΔNp73 present a higher avidity for the peritoneum and that extracellular vesicles secreted by ΔNp73-upregulating tumor cells enhance their dissemination. In addition, we identified that tumor cells overexpressing ΔNp73 present with dysregulation of genes associated with an epithelial/mesothelial-to-mesenchymal transition (MMT) and that mesothelial cells exposed to the conditioned medium of tumor cells with upregulated ΔNp73 present a mesenchymal phenotype. Lastly, ΔNp73 and its effector target RNAs were dysregulated in our patient series, there were positive correlations between ΔNp73 and its effector targets, and MSN and ITGB4 (ΔNp73 effectors) predicted patient survival. In conclusion, ΔNp73 and its effector targets are involved in the peritoneal dissemination of colorectal cancer and predict patient survival. The promotion of the EMT/MMT and modulation of the adhesion capacity in colorectal cancer cells might be the mechanisms triggered by ΔNp73. Remarkably, ΔNp73 protein is a druggable protein and should be the focus of future studies. © 2024 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Bringing to Light the Importance of the miRNA Methylome in Colorectal Cancer Prognosis Through Electrochemical Bioplatforms.

This work reports the first electrochemical bioplatforms developed for the determination of the total contents of either target miRNA or methylated target miRNA. The bioplatforms are based on the hybridization of the target miRNA with a synthetic biotinylated DNA probe, the capture of the formed DNA/miRNA heterohybrids on the surface of magnetic microcarriers, and their recognition with an antibody selective to these heterohybrids or to the N6-methyladenosine (m6A) epimark. The determination of the total or methylated target miRNA was accomplished by labeling such secondary antibodies with the horseradish peroxidase (HRP) enzyme. In both cases, amperometric transduction was performed on the surface of disposable electrodes after capturing the resulting HRP-tagged magnetic bioconjugates. Because of their increasing relevance in colorectal cancer (CRC) diagnosis and prognosis, miRNA let-7a and m6A methylation were selected. The proposed electrochemical bioplatforms showed attractive analytical and operational characteristics for the determination of the total and m6A-methylated target miRNA in less than 75 min. These bioplatforms, innovative in design and application, were applied to the analysis of total RNA samples extracted from cultured cancer cells with different metastatic profiles and from paired healthy and tumor tissues of patients diagnosed with CRC at different stages. The obtained results demonstrated, for the first time using electrochemical platforms, the potential of interrogating the target miRNA methylation level to discriminate the metastatic capacities of cancer cells and to identify tumor tissues and, in a pioneering way, the potential of the m6A methylation in miRNA let-7a to serve as a prognostic biomarker for CRC.

Proteomics analysis of prefrontal cortex of Alzheimer's disease patients revealed dysregulated proteins in the disease and novel proteins associated with amyloid-ß pathology.

BACKGROUND: Alzheimer's disease (AD) is a progressive, chronic, and neurodegenerative disease, and the most common cause of dementia worldwide. Currently, the mechanisms underlying the disease are far from being elucidated. Thus, the study of proteins involved in its pathogenesis would allow getting further insights into the disease and identifying new markers for AD diagnosis. METHODS: We aimed here to analyze protein dysregulation in AD brain by quantitative proteomics to identify novel proteins associated with the disease. 10-plex TMT (tandem mass tags)-based quantitative proteomics experiments were performed using frozen tissue samples from the left prefrontal cortex of AD patients and healthy individuals and vascular dementia (VD) and frontotemporal dementia (FTD) patients as controls (CT). LC-MS/MS analyses were performed using a Q Exactive mass spectrometer. RESULTS: In total, 3281 proteins were identified and quantified using MaxQuant. Among them, after statistical analysis with Perseus (p value < 0.05), 16 and 155 proteins were defined as upregulated and downregulated, respectively, in AD compared to CT (Healthy, FTD and VD) with an expression ratio ≥ 1.5 (upregulated) or ≤ 0.67 (downregulated). After bioinformatics analysis, ten dysregulated proteins were selected as more prone to be associated with AD, and their dysregulation in the disease was verified by qPCR, WB, immunohistochemistry (IHC), immunofluorescence (IF), pull-down, and/or ELISA, using tissue and plasma samples of AD patients, patients with other dementias, and healthy individuals. CONCLUSIONS: We identified and validated novel AD-associated proteins in brain tissue that should be of further interest for the study of the disease. Remarkably, PMP2 and SCRN3 were found to bind to amyloid-ß (Aß) fibers in vitro, and PMP2 to associate with Aß plaques by IF, whereas HECTD1 and SLC12A5 were identified as new potential blood-based biomarkers of the disease.

First bioelectronic immunoplatform for quantitative secretomic analysis of total and metastasis-driven glycosylated haptoglobin.

The glycosylation status of proteins is increasingly used as biomarker to improve the reliability in the diagnosis and prognosis of diseases as relevant as cancer. This feeds the need for tools that allow its simple and reliable analysis and are compatible with applicability in the clinic. With this objective in mind, this work reports the first bioelectronic immunoplatforms described to date for the determination of glycosylated haptoglobin (Hp) and the simultaneous determination of total and glycosylated Hp. The bioelectronic immunoplatform is based on the implementation of non-competitive bioassays using two different antibodies or an antibody and a lectin on the surface of commercial magnetic microcarriers. The resulting bioconjugates are labeled with the horseradish peroxidase (HRP) enzyme, and after their magnetic capture on disposable electroplatforms, the amperometric transduction using the H2O2/hydroquinone (HQ) system allows the single or multiple detection. The developed immunoplatform achieves limits of detection (LODs) of 0.07 and 0.46 ng mL-1 for total and glycosylated Hp in buffer solution, respectively. The immunoplatform allows accurate determination using simple and relatively short protocols (approx. 75 min) of total and glycosylated Hp in the secretomes of in vitro-cultured colorectal cancer (CRC) cells with different metastatic potentials, which is not feasible, due to lack of sensitivity, by means of some commercial ELISA kits and Western blot methodology.

Surface stabilisation of the high-spin state of Fe(II) spin-crossover complexes.

Temperature dependent X-ray photoemission spectroscopy (XPS) has been employed to examine the Fe 2p and N 1s core levels of the studied Fe(II) spin crossover (SCO) complexes of interest, namely: Fe(phen)2(NCS)2, [Fe(3-Fpy)2{Ni(CN)4}], and [Fe(3-Fpy)2{Pt(CN)4}]. The changes in the Fe 2p core-level spectra with temperature indicate spin state transitions in these SCO complexes, which are consistent with one's expectations and the existing literature. Additionally, the temperature dependence of the binding energy of the N 1s core-level provides further physical insights into the ligand-to-metal charge transfer phenomenon in these molecules. The high-spin fraction versus temperature plots reveal that the surface of each of the molecules studied herein is found to be in the high-spin state at temperatures both in the vicinity of room temperature and below their respective transition temperature alike, with the stability of the high-spin state of these molecules varying with the choice of ligand.

Effect of prenatal exposure to organophosphates and pyrethroid pesticides on neonatal anthropometric measures and gestational age.

Several studies have examined the association between prenatal exposure to organophosphate and pyrethroid pesticides and their impact on foetal growth and newborn anthropometry; however, the available evidence is limited and inconclusive. This study examined whether prenatal organophosphate and pyrethroid pesticide exposure was associated with anthropometric measures at birth (weight, length, head circumference), ponderal index, gestational age, and prematurity in 537 mother-child pairs. These were randomly selected from the 800 pairs participating in the prospective birth cohort GENEIDA (Genetics, early life environmental exposures and infant development in Andalusia). Six non-specific organophosphate metabolites (dialkylphosphates, DAPs), one metabolite relatively specific to chlorpyrifos (3,5,6-trichloro-2-pyridinol, TCPy) and a common metabolite to several pyrethroids (3-phenoxybenzoic acid, 3-PBA) were measured in maternal urine from the 1st and 3rd pregnancy trimesters. Information on anthropometric measures at birth, gestational age and prematurity was retrieved from medical records. The sum on a molar basis of DAPs with methyl (Æ©DMs) and ethyl (Æ©DEs) moieties and the sum of the 6 DAPs metabolites (Æ©DAPs) was calculated for both trimesters of pregnancy. High urinary levels of dimethyl phosphate (DMP) during the 3rd trimester were associated with a decrease in birth weight (ß = -0.24; 95% CI: 0.41; -0.06) and birth length (ß = -0.20; 95% CI: 0.41; 0.02). Likewise, ΣDMs during 3rd trimester were near-significantly associated with decreased birth weight (ß = -0.18; 95% CI: 0.37; 0.01). In turn, increased urinary TCPy during 1st trimester was associated with a decreased head circumference (ß = -0.31; 95% CI: 0.57; -0.06). Finally, an increase in 3-PBA in the 1st trimester was associated with a decreased gestational age (ß = -0.36 95% CI: 0.65-0.08), whereas increased 3-PBA at 1st and 3rd trimester was associated with prematurity. These results indicate that prenatal exposure to organophosphate and pyrethroid insecticides could affect normal foetal growth, shorten gestational age and alter anthropometric measures at birth.

Effect of a Multimodal Supervised Therapeutic Exercise Program on Quality of Life, Pain, and Lumbopelvic Impairments in Women With Endometriosis Unresponsive to Conventional Therapy: A Randomized Controlled Trial.

OBJECTIVE: To evaluate the effectiveness of "Physio-EndEA", a multimodal nine-week supervised exercise intervention, on quality of life, pain, and lumbopelvic impairments in women with endometriosis unresponsive to conventional therapy. DESIGN: Parallel-group randomized controlled trial. Outcomes were measured at baseline, post-intervention, and at 1 year. SETTING: Two Public University Hospitals. PARTICIPANTS: This trial included 31 women with endometriosis (N=31) randomly allocated to "Physio-EndEA" group (n=16) or control group (n=15). Four participants dropped out of the study for causes unrelated to the intervention. INTERVENTIONS: The "Physio-EndEA" program consisted of a 1-week lumbopelvic stabilization learning phase followed by an 8-week phase of stretching, aerobic, and resistance exercises focused on the lumbopelvic area. It was sequentially instructed and supervised by a trained physiotherapist (with volume and intensity progression) and adapted daily to the potential of each participant. Control group received the usual treatment stipulated by their gynecologist. MAIN OUTCOME MEASURES: The primary outcome was quality of life. Secondary outcomes were pain intensity, pressure pain thresholds, pain-related catastrophic thoughts, abdominal and back strength, lumbopelvic stability, and muscle architecture. RESULTS: Adherence rate was 90.6% and mean (±standard deviation) satisfaction was 9.44±0.73 out of 10. No remarkable health problems were reported during the trial. In comparison with controls, the quality of life was improved post-intervention and at 1 year in the Physio-EndEA group with large effect sizes (d>0.80). This group also evidenced: a reduced intensity of dyspareunia, catastrophic thoughts; an increase in pelvic, lumbar, and distal pressure pain thresholds; increases in abdominal and back strength and lumbopelvic stability; and increased thickness of transversus abdominis (right side) and width of lumbar multifidus (left side). CONCLUSION: A 9-week program of multimodal supervised therapeutic exercise is a feasible and effective intervention to improve QoL in women with endometriosis. This program also offers benefits in terms of pain/sensitization and lumbopelvic impairments.

Multispectral Imaging Method for Rapid Identification and Analysis of Paraffin-Embedded Pathological Tissues.

The study of the interaction between light and biological tissue is of great help in the identification of diseases as well as structural alterations in tissues. In the present study, we have developed a tissue diagnostic technique by using multispectral imaging in the visible spectrum combined with principal component analysis (PCA). We used information from the propagation of light through paraffin-embedded tissues to assess differences in the eye tissues of control mouse embryos compared to mouse embryos whose mothers were deprived of folic acid (FA), a crucial vitamin necessary for the growth and development of the fetus. After acquiring the endmembers from the multispectral images, spectral unmixing was used to identify the abundances of those endmembers in each pixel. For each acquired image, the final analysis was performed by performing a pixel-by-pixel and wavelength-by-wavelength absorbance calculation. Non-negative least squares (NNLS) were used in this research. The abundance maps obtained for the first endmember revealed vascular alterations (vitreous and choroid) in the embryos with maternal FA deficiency. However, the abundance maps obtained for the third endmember showed alterations in the texture of some tissues such as the lens and retina. Results indicated that multispectral imaging applied to paraffin-embedded tissues enhanced tissue visualization. Using this method, first, it can be seen tissue damage location and then decide what kind of biological techniques to apply.

Spatial Control of Charge Doping in n-Type Topological Insulators.

Spatially controlling the Fermi level of topological insulators and keeping their electronic states stable are indispensable processes to put this material into practical use for semiconductor spintronics devices. So far, however, such a method has not been established yet. Here we show a novel method for doping a hole into n-type topological insulators Bi2X3 (X= Se, Te) that overcomes the shortcomings of the previous reported methods. The key of this doping is to adsorb H2O on Bi2X3 decorated with a small amount of carbon, and its trigger is the irradiation of a photon with sufficient energy to excite the core electrons of the outermost layer atoms. This method allows controlling the doping amount by the irradiation time and acts as photolithography. Such a tunable doping makes it possible to design the electronic states at the nanometer scale and, thus, paves a promising avenue toward the realization of novel spintronics devices based on topological insulators.

Quasicrystalline 30° twisted bilayer graphene as an incommensurate superlattice with strong interlayer coupling.

The interlayer coupling can be used to engineer the electronic structure of van der Waals heterostructures (superlattices) to obtain properties that are not possible in a single material. So far research in heterostructures has been focused on commensurate superlattices with a long-ranged Moiré period. Incommensurate heterostructures with rotational symmetry but not translational symmetry (in analogy to quasicrystals) are not only rare in nature, but also the interlayer interaction has often been assumed to be negligible due to the lack of phase coherence. Here we report the successful growth of quasicrystalline 30° twisted bilayer graphene (30°-tBLG), which is stabilized by the Pt(111) substrate, and reveal its electronic structure. The 30°-tBLG is confirmed by low energy electron diffraction and the intervalley double-resonance Raman mode at 1383 cm-1 Moreover, the emergence of mirrored Dirac cones inside the Brillouin zone of each graphene layer and a gap opening at the zone boundary suggest that these two graphene layers are coupled via a generalized Umklapp scattering mechanism-that is, scattering of a Dirac cone in one graphene layer by the reciprocal lattice vector of the other graphene layer. Our work highlights the important role of interlayer coupling in incommensurate quasicrystalline superlattices, thereby extending band structure engineering to incommensurate superstructures.

Visualizing the Effect of an Electrostatic Gate with Angle-Resolved Photoemission Spectroscopy.

Electrostatic gating is pervasive in materials science, yet its effects on the electronic band structure of materials has never been revealed directly by angle-resolved photoemission spectroscopy (ARPES), the technique of choice to noninvasively probe the electronic band structure of a material. By means of a state-of-the-art ARPES setup with submicron spatial resolution, we have investigated a heterostructure composed of Bernal-stacked bilayer graphene (BLG) on hexagonal boron nitride and deposited on a graphite flake. By voltage biasing the latter, the electric field effect is directly visualized on the valence band as well as on the carbon 1s core level of BLG. The band gap opening of BLG submitted to a transverse electric field is discussed and the importance of intra layer screening is put forward. Our results pave the way for new studies that will use momentum-resolved electronic structure information to gain insight on the physics of materials submitted to the electric field effect.

Nanomosaic of Topological Dirac States on the Surface of Pb5Bi24Se41 Observed by Nano-ARPES.

We have performed scanning angle-resolved photoemission spectroscopy with a nanometer-sized beam spot (nano-ARPES) on the cleaved surface of Pb5Bi24Se41, which is a member of the (PbSe)5(Bi2Se3)3 m homologous series (PSBS) with m = 4 consisting of alternate stacking of the topologically trivial insulator PbSe bilayer and four quintuple layers (QLs) of the topological insulator Bi2Se3. This allows us to visualize a mosaic of topological Dirac states at a nanometer scale coming from the variable thickness of the Bi2Se3 nanoislands (1-3 QLs) that remain on top of the PbSe layer after cleaving the PSBS crystal, because the local band structure of topological origin changes drastically with the thickness of the Bi2Se3 nanoislands. A comparison of the local band structure with that in ultrathin Bi2Se3 films on Si(111) gives us further insights into the nature of the observed topological states. This result demonstrates that nano-ARPES is a very useful tool for characterizing topological heterostructures.

The Role of Oxygen Atoms on Excitons at the Edges of Monolayer WS2.

We clarify that the chemisorption of oxygen atoms at the edges is a key contributor to the frequently observed edge enhancement and spatial non-uniformities of photoluminescence (PL) in WS2 monolayers. Here we have investigated with momentum- and real-space nanoimaging of the chemical and electronic density inhomogeneity of WS2 flakes. Our finding from a large panoply of techniques together with density functional theory calculation confirms that the oxygen chemisorption leads to the electron accumulation at the edges. This facilitates the trion dominance of PL at the edges of WS2 flakes. Our results highlight and unravel the significance of chemisorbed oxygen at the edges in the PL emission and electronic structure of WS2, providing a viable path to enhance the performance of transition-metal-dichalcogenide-based devices.

Retraction Note: Large local lattice expansion in graphene adlayers grown on copper.

The authors unanimously wish to retract this Article due to their concerns about the interpretation of the low-energy electron microscopy (LEEM) and diffraction (LEED) patterns reported in the manuscript. In this study, the authors used spatial and angle-resolved photoemission spectroscopy (ARPES) to characterize graphene monolayers grown on copper foils, and observed regions of graphene adlayers with enhanced graphene/Cu interaction, higher Dirac cone doping level, moiré mini Dirac cones and large lattice expansion. All these properties have been clearly verified and reproduced by photoemission spectroscopy as well as explained by density functional theory. LEEM and LEED characterization were also carried out to confirm the existence of a moiré superlattice and lattice expansion, and the results were included in the main manuscript and Supplementary Information. On further analysis of the LEEM/LEED data, it seems that while the existence of a moiré superlattice can be corroborated, the conclusion of graphene lattice expansion (7%) based on spatially resolved ARPES determinations cannot be confirmed by the LEEM/LEED measurements. The authors realized that these measurements were collected from statistically non-representative areas of the sample. Moreover, the fact that the raw microLEED images bear an asymmetry factor of as much as 5% due to the instrumental aberration makes it impossible to estimate any compression or expansion of the same order. Consequently, their conclusion on the graphene lattice expansion can only be supported by the photoemission data. In view that more complete and reliable structural determinations should be conducted, all authors wish to retract this Article.

Large local lattice expansion in graphene adlayers grown on copper.

Variations of the lattice parameter can significantly change the properties of a material, and, in particular, its electronic behaviour. In the case of graphene, however, variations of the lattice constant with respect to graphite have been limited to less than 2.5% due to its well-established high in-plane stiffness. Here, through systematic electronic and lattice structure studies, we report regions where the lattice constant of graphene monolayers grown on copper by chemical vapour deposition increases up to ~7.5% of its relaxed value. Density functional theory calculations confirm that this expanded phase is energetically metastable and driven by the enhanced interaction between the substrate and the graphene adlayer. We also prove that this phase possesses distinctive chemical and electronic properties. The inherent phase complexity of graphene grown on copper foils revealed in this study may inspire the investigation of possible metastable phases in other seemingly simple heterostructure systems.

Alteration of lens and retina textures from mice embryos with folic acid deficiency: image processing analysis.

PURPOSE: Folic acid (FA) is an essential vitamin for embryonic development. It plays particularly a critical role in RNA, DNA and protein synthesis. On the other hand, the collagen IV and laminin-1 are important proteins during embryonic development. This study was done to find if FA deficiency at a short and a long term in mothers could alter the tissue texture of retina and lens of the progeny. METHODS: Collagen IV and laminin-1 were localized by immunohistochemistry in the lens and retina of the FA-deficient embryos. To carry out the image processing, texture segmentation was performed through canny edge detection and Fourier transform (FT). We defined a parameter, the grain size, to describe the texture of the lens and retina. A bootstrap method to estimate the distribution and confidence intervals of the mean, standard deviation, skewness and kurtosis of the grain size has been developed. RESULTS: Analysis through image processing using Matlab showed changes in the grain size between control- and FA-deficient groups in both studied molecules. Measures of texture based on FT exhibited changes in the directionality and arrangements of type IV collagen and laminin-1. CONCLUSIONS: Changes introduced by FA deficiency were visible in the short term (2 weeks) and evident in the long term (8 weeks) in both grain size and orientation of fibre structures in the tissues analysed (lens and retina). This is the first work devoted to study the effect of FA deficit in the texture of eye tissues using image processing techniques.

Simultaneous amperometric immunosensing of the metastasis-related biomarkers IL-13Rα2 and CDH-17 by using grafted screen-printed electrodes and a composite prepared from quantum dots and carbon nanotubes for signal amplification.

This paper describes a dual electrochemical immunoassay for the simultaneous determination of IL-13Rα2 and CDH-17, two biomarkers of emerging relevance in metastatic processes. The sandwich assay uses a screen-printed dual carbon electrode that was electrochemically grafted with p-aminobenzoic acid to allow the covalent immobilization of capture antibodies. A hybrid composed of graphene quantum dots (GQDs) and multiwalled carbon nanotubes (MWCNTs) act as nanocarriers for the detection antibodies and horseradish peroxidase. The use of this hybrid material considerably improves the assay (in comparison to the use of MWCNTs) due to the peroxidase mimicking activity of the GQDs. The method works at a low working potential (0.20 V vs. Ag pseudo-reference electrode) and thus is not readily interfered by unknown electroactive species. The dual immunoassay allows for the selective determination of both biomarkers with LOD values of 1.4 (IL-13sRα2) and 0.03 ng mL-1 (CDH-17). The simultaneous determination of IL-13Rα2 and CDH-17 was accomplished in lysates from breast and colorectal cancer cells with different metastatic potential, and in paraffin-embedded tumor tissues extracts from patients diagnosed with colorectal cancer at different stages. The applicability to discriminate the metastatic potential even in intact cells through the detection of both extracellular receptors has been demonstrated also. The assay can be performed within 3 h, requires small sample amounts (0.5 µg), and has a simple protocol. Graphical abstract Dual amperometric immunosensing of the metastasis-related biomarkers IL-13Rα2 and CDH-17 in human colorectal cancer cells and tissues by using grafted screen-printed electrodes and composites of quantum dots and carbon nanotubes as nanocarriers.

Emergence of Interfacial Polarons from Electron-Phonon Coupling in Graphene/h-BN van der Waals Heterostructures.

van der Waals heterostructures, vertical stacks of layered materials, offer new opportunities for novel quantum phenomena which are absent in their constituent components. Here we report the emergence of polaron quasiparticles at the interface of graphene/hexagonal boron nitride (h-BN) heterostructures. Using nanospot angle-resolved photoemission spectroscopy, we observe zone-corner replicas of h-BN valence band maxima, with energy spacing coincident with the highest phonon energy of the heterostructure, an indication of Fröhlich polaron formation due to forward-scattering electron-phonon coupling. Parabolic fitting of the h-BN bands yields an effective mass enhancement of ∼2.3, suggesting an intermediate coupling strength. Our theoretical simulations based on Migdal-Eliashberg theory corroborate the experimental results, allowing the extraction of microscopic physical parameters. Moreover, renormalization of graphene π-band is observed due to the hybridization with the h-BN band. Our work generalizes the polaron study from transition metal oxides to van der Waals heterostructures with higher material flexibility, highlighting interlayer coupling as an extra degree of freedom to explore emergent phenomena.

Resolving Deep Quantum-Well States in Atomically Thin 2H-MoTe2 Flakes by Nanospot Angle-Resolved Photoemission Spectroscopy.

Transition-metal dichalcogenides exhibit strong quantum confinement effects, and their electronic structure is strongly dependent on the number of layers. Resolving the thickness-dependent electronic structure is important. While the electronic structure of atomically thin 2H-MoSe2 or 2H-MoS2 have been explored, information on the experimental electronic structure of 2H-MoTe2 is still missing. Here, by using nanospot angle-resolved photoemission spectroscopy (nanoARPES), we reveal the experimental electronic structure of exfoliated 2H-MoTe2 thin flakes with different thickness (three, five, and seven monolayers). Well-separated quantum-well states are clearly observed in thin 2H-MoTe2 flakes at deep valence bands at energies between -3 to -5 eV, while those at the top of the valence band between -1 and -2 eV are much more closely spaced compared with those from 2H-MoSe2 and 2H-MoS2. First-principles calculation shows that the main difference is attributed to the weaker hybridization and smaller energy difference between Mo 4d z2 and Te 5p z orbitals as compared with Se 4p z and S 3p z orbitals. Our work demonstrates the power of nanoARPES in resolving the electronic structure of atomically thin exfoliated flakes.

Determination of Cadherin-17 in Tumor Tissues of Different Metastatic Grade Using a Single Incubation-Step Amperometric Immunosensor.

This paper reports the development of an amperometric immunosensing platform for the determination of cadherin-17 (CDH-17), an atypical adhesion protein involved in the progression, metastatic potential, and survival of high prevalence gastric, hepatocellular, and colorectal tumors. The methodology developed relies on the efficient capture and enzymatic labeling of the target protein on the magnetic microparticles (MBs) surface using commercial antibodies and amperometric transduction at screen-printed carbon electrodes (SCPEs) through the HRP/H2O2/HQ system. The developed immunosensing platform allows the selective determination of the target protein at low ng mL-1 level (LOD of 1.43 ng mL-1) in 45 min and using a single incubation step. The electrochemical immunosensor was successfully used for the accurate determination of the target protein in a small amount (0.5 µg) of raw lysates of colon cancer cells with different metastatic potential as well as in extracts from paraffin embedded cancer colon tissues of different metastatic grade.