Clusters supported by solid substrates are prime candidates for heterogeneous catalysis and can be prepared in various ways. While mass-selected soft-landing methods are often used for the generation of monodisperse particles, self-assembly typically leads to a range of different cluster sizes. Here we show by scanning tunneling microscopy measurements that in the initial stages of growth, Mn forms trimers on a close-packed hexagonal Ir surface, providing a route for self-organized monodisperse cluster formation on an isotropic metallic surface.
View Article and Find Full Text PDFPlant diversity includes over 300,000 species, and leaf structure is one of the main targets of selection, being highly variable in shape and size. On the other hand, the optimization of antenna design has no unique solution to satisfy the current range of applications. We analyzed the foliar geometries of 100 plant species and applied them as a biomimetic design template for microstrip patch antenna systems.
View Article and Find Full Text PDFChiral spin textures are fundamentally interesting, with promise for device applications. Stabilizing chirality is conventionally achieved by introducing Dzyaloshinskii-Moriya interaction (DMI) in asymmetric multilayers, where the thickness of each layer is at least a few monolayers. Here we report an ultrasensitive chirality switching in (Ni/Co) multilayer induced by capping with only 0.
View Article and Find Full Text PDFBackground: Zygomatic implants have been proposed alone or in combination with premaxillary conventional implants for severe resorbed maxillary atrophy rehabilitation. The aim of the present investigation was to evaluate through a qualitative systematic review and meta-analysis the survival rate of zygomatic implants in conjunction with regular fixtures for maxillary rehabilitation.
Methods: The article screening was conducted on the PubMed/Medline and EMBASE electronic databases according to the "Preferred Reporting Items for Systematic Reviews and Meta-Analyses" (PRISMA) guidelines.
Background: Zygomatic implants have been proposed in literature for atrophic maxillary fixed oral rehabilitations. The aim of the present research was to evaluate, by a clinical and tomography assessment, a surgical complication of a zygomatic implant penetration to the orbit.
Case Presentation: A 56 year-old female patient was visited for pain and swelling in the left orbit after a zygomatic implant protocol.
The Dzyaloshinskii-Moriya interaction (DMI) is an antisymmetric exchange interaction that stabilizes chiral spin textures. It is induced by inversion symmetry breaking in noncentrosymmetric lattices or at interfaces. Recently, interfacial DMI has been found in magnetic layers adjacent to transition metals due to the spin-orbit coupling and at interfaces with graphene due to the Rashba effect.
View Article and Find Full Text PDFBackground: Temporo-mandibular disorders (TMD) is a collective term comprehending different clinical issues involving masticatory muscles, temporo-mandibular joint (TMJ) and other associated structures. TMD diagnosis is not made for its pathogenesis or etiology, but mainly on clinical symptoms. Primary dysfunction develops mostly on four factors: individual predisposition, high psychomotor activity (due to stress or parafunction), occlusal instability and low or absent tissue adaptation capability.
View Article and Find Full Text PDFStrain-coupled multiferroic heterostructures provide a path to energy-efficient, voltage-controlled magnetic nanoscale devices, a region where current-based methods of magnetic control suffer from Ohmic dissipation. Growing interest in highly magnetoelastic materials, such as Terfenol-D, prompts a more accurate understanding of their magnetization behavior. To address this need, we simulate the strain-induced magnetization change with two modeling methods: the commonly used unidirectional model and the recently developed bidirectional model.
View Article and Find Full Text PDFComposite multiferroic systems, consisting of a piezoelectric substrate coupled with a ferromagnetic thin film, are of great interest from a technological point of view because they offer a path toward the development of ultralow power magnetoelectric devices. The key aspect of those systems is the possibility to control magnetization via an electric field, relying on the magneto-elastic coupling at the interface between the piezoelectric and the ferromagnetic components. Accordingly, a direct measurement of both the electrically induced magnetic behavior and of the piezo-strain driving such behavior is crucial for better understanding and further developing these materials systems.
View Article and Find Full Text PDFBeilstein J Nanotechnol
February 2013
Patterning of materials at sub-10 nm dimensions is at the forefront of nanotechnology and employs techniques of various complexity, efficiency, areal scale, and cost. Colloid-based patterning is known to be capable of producing individual sub-10 nm objects. However, ordered, large-area nano-arrays, fully integrated into photonic or electronic devices have remained a challenging task.
View Article and Find Full Text PDFFifteen multiple myeloma (MM) patients who had failed maintenance therapy after tandem autologous stem cell transplantation underwent anti-idiotype (Id) vaccination with dendritic cells (DCs). CD14(+)-derived DCs were loaded with the autologous Id as whole protein (=6) or Id-derived class I-restricted peptides (=9) and keyhole limpet hemocyanin (KLH). Vaccination consisted of three subcutaneous (sc) and two intravenous injections of increasing DC doses at 2 weeks interval.
View Article and Find Full Text PDFWe assessed the capacity of positively selected autologous CD133(+) hematopoietic stem cells (HSCs) to reconstitute lymphomyelopoiesis in chronic lymphocytic leukemia (CLL) patients receiving myeloablative chemotherapy. Ten resistant/relapsed CLL patients underwent HSC mobilization with chemotherapy and granulocyte-colony stimulating factor (G-CSF). Positive selection of circulating CD133(+) HSCs was performed by immunomagnetic technique.
View Article and Find Full Text PDFHuman mesenchymal stromal (stem) cells (hMSCs) isolated from adult bone marrow (BM-hMSCs) as well as amnion (AM-hMSCs) and chorion (CM-hMSCs) term placenta leaves were studied by transmission electron microscopy (TEM) to investigate their ultrastructural basic phenotype. At flow cytometry, the isolated cells showed a homogeneous expression of markers commonly used to identify hMSCs, i.e.
View Article and Find Full Text PDFThe clinical use of endothelial progenitor cells is hampered by difficulties in obtaining an adequate number of functional progenitors. This study aimed to establish whether human thoracic aortas harvested from healthy multiorgan donors can be a valuable source of angiogenic progenitors. Immunohistochemical tissue studies showed that two distinct cell populations with putative stem cell capabilities, one composed of CD34+ cells and the other of c-kit+ cells, are present in between the media and adventitia of human thoracic aortas.
View Article and Find Full Text PDFTo investigate the mechanisms involved in the human immunodeficiency virus type 1 (HIV-1)-related thrombocytopenia (TP), human umbilical cord blood (UCB) CD34(+) hematopoietic progenitor cells (HPCs) were challenged with HIV-1(IIIb) and then differentiated by thrombopoietin (TPO) towards megakaryocytic lineage. This study showed that HIV-1, heat-inactivated HIV-1, and HIV-1 recombinant gp120 (rgp120) activated apoptotic process of megakaryocyte (MK) progenitors/precursors and decreased higher ploidy MK cell fraction. All these inhibitory effects on MK survival/maturation and platelets formation were elicited by the interaction between gp120 and CD4 receptor on the cell membrane in the absence of HIV-1 productive infection.
View Article and Find Full Text PDFBackground: The beta-herpesvirus human cytomegalovirus (HCMV) infects a variety of cell types and maintains a lifelong relationship with its host by way of a latent infection in circulating monocytes, myeloid precursor cells, and the hematopoietic progenitor population. Viral strain heterogeneity, shown by gene polymorphisms, has been implicated in the majority of HCMV biologic behaviors. HCMV UL73 encodes the polymorphic envelope glycoprotein N (gN), which shows seven genotypes (gN-1, gN-2, gN-3a, gN-3b, gN-4a, gN-4b, and gN-4c).
View Article and Find Full Text PDFObjective: Altered self-antigen processing/presentation of apoptotic cells by DCs and/or modifications of autoantigens may lead to the development of autoantibodies. Increasing evidence indicates that platelets may undergo apoptosis. Therefore, in the present study we investigated whether platelet apoptosis and/or dendritic cells (DCs) may play a role in the stimulation of the immuno-mediated anti-platelet response in chronic immune thrombocytopenic purpura (ITP).
View Article and Find Full Text PDFHemolytic-uremic syndrome, the main cause of acute renal failure in early childhood, is caused primarily by intestinal infections from some Escherichia coli strains that produce Shiga toxins. The toxins released in the gut are targeted to renal endothelium after binding to polymorphonuclear leukocytes. The presence of Shiga toxins in the feces and the circulating neutrophils of 20 children with hemolytic uremic syndrome was evaluated by the Vero cell cytotoxicity assay and flow cytometric analysis, respectively.
View Article and Find Full Text PDFWe hypothesized that the effects of extracorporeal photopheresis (ECP) are mediated by induction of immunosuppressive cytokines like IL-10, which enhances synthesis of HLA-G molecules. HLA-G products are expressed by CD14+ peripheral blood mononuclear cells (PBMC) and play an important role in inhibition of cell mediated immunity. ECP induces apoptosis in lymphocytes but not in CD14+ cells.
View Article and Find Full Text PDFActivation of the phosphoinositide 3 kinase (PI3K)/Akt signalling pathway has been linked with resistance to chemotherapeutic drugs, and its downregulation, by means of PI3K inhibitors, lowers resistance to various types of therapy in tumour cell lines. Recently, it has been reported that deguelin, a naturally occurring rotenoid, is a powerful inhibitor of PI3K. We investigated whether or not deguelin could enhance the sensitivity to chemotherapeutic drugs of human U937 leukaemia cells and acute myeloid leukaemia (AML) blasts with an activated PI3K/Akt network.
View Article and Find Full Text PDFBackground And Objectives: The aim of this study was to evaluate the efficacy of pegfilgrastim, in combination with salvage chemotherapy, in mobilizing CD34(+) stem cells into the peripheral blood of pretreated lymphoma patients.
Design And Methods: This was an open-label phase II study including 25 pretreated patients (Hodgkin's disease=4; aggressive non-Hodgkin's lymphoma=21). The primary end-point of the study was the successful mobilization of a target cell dose of 2x10(6) CD34(+) cells/kg in lymphoma patients receiving ifosfamide, epirubicin and etoposide (IEV) chemotherapy and a fixed dose (6 mg) of pegfilgrastim given as single subcutaneous injection.
Background: Hemolytic uremic syndrome (HUS) is the main cause of acute renal failure in early childhood. Most cases are due to intestinal infections from Escherichia coli strains (STEC) which produce by Shiga toxin (Stxs). Stx1 and Stx2 produced by STEC in the gut are absorbed into the circulation and, after binding on polymorphonuclear leukocytes (PMNs), are targeted to renal endothelium.
View Article and Find Full Text PDFThe phosphoinositide 3-kinase/Akt signalling pathway is a recently recognized important parameter in the prognosis and the response to treatment of acute myeloid leukaemia (AML). Akt kinase is activated by phosphorylation on Thr 308 and Ser 473. Active Akt promotes cell growth and survival to apoptotic insults.
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