Fine-tuned local coordination environment of Pt single atoms on ceria controls catalytic reactivity.

Constructing single atom catalysts with fine-tuned coordination environments can be a promising strategy to achieve satisfactory catalytic performance. Herein, via a simple calcination temperature-control strategy, CeO supported Pt single atom catalysts with precisely controlled coordination environments are successfully fabricated. The joint experimental and theoretical analysis reveals that the Pt single atoms on Pt/CeO prepared at 550 °C (Pt/CeO-550) are mainly located at the edge sites of CeO with a Pt-O coordination number of ca.

Atomic-Scale Structure and Catalysis on Positively Charged Bimetallic Sites for Generation of H.

Here, we report that a cationic bimetallic site consisting of one Pd and three Zn atoms (PdZn) supported on ZnO (PdZn/ZnO) exhibits an extraordinarily high catalytic activity for the generation of H through methanol partial oxidation (MPO) that is 2-3 orders of magnitude higher than that of a metallic Pd-Zn site on Pd-Zn nanoalloy (Pd-Zn/ZnO). Computational studies uncovered that the positively charged Pd atom of the subnanometer PdZn bimetallic site largely decreases the activation barrier for dehydrogenation of methanol as compared to a metallic Pd atom of Pd-Zn alloy, thus switching the rate-determining step of MPO from methanol dehydrogenation over a Pd-Zn alloy with high barrier to the O dissociation step on a cationic PdZn site with a low barrier, which is supported by our kinetics studies. The significantly higher catalytic activity and selectivity for H production over a cationic bimetallic site suggest a new approach to design bimetallic catalysts.

Adatom Extraction from Pristine Metal Terraces by Dissociative Oxygen Adsorption: Combined STM and Density Functional Theory Investigation of O/Ag(110).

The reconstruction and modification of metal surfaces upon O_{2} adsorption plays an important role in oxidation processes and in gauging their catalytic activity. Here, we show by employing scanning tunneling microscopy and the ab initio density functional theory that Ag atoms are extracted from pristine (110) terraces upon O_{2} dissociation, resulting in vacancies and in Ag-O complexes. The substrate roughening generates undercoordinated atoms and opens pathways to the Ag subsurface layer.

Accelerated biodegradation of silk sutures through matrix metalloproteinase activation by incorporating 4-hexylresorcinol.

Silk suture material is primarily composed of silk fibroin and regarded as a non-resorbable material. It is slowly degraded by proteolysis when it is implanted into the body. 4-Hexylresorcinol (4HR) is a well-known antiseptic.

Atypical granular cell tumor in the maxilla: The first report of primary intraosseous granular cell tumor.

Background: Granular cell tumor (GCT) is a benign soft tissue tumor of neural origin and is characterized by eosinophilic granular cells showing positivity for neuronal markers. Herein, we report the first case of primary intraosseous GCT arising in the maxilla of an adolescent girl.

Methods And Results: A 16-year-old female patient presented with palatal swelling.

KiSS-1 expression in oral squamous cell carcinoma and its prognostic significance.

Downregulated expression of KiSS-1 has been correlated with tumor progression, metastasis, and patient prognosis in various human malignancies. However, there is no information regarding the expression of KiSS-1 in oral squamous cell carcinoma (OSCC). Our aims were to examine KiSS-1 expression in OSCC tissue samples and cell lines and to determine its prognostic significance.

Thymosin β4 induces proliferation, invasion, and epithelial-to-mesenchymal transition of oral squamous cell carcinoma.

The epithelial-to-mesenchymal transition (EMT) plays a vital role in carcinogenesis, invasion, and metastasis of many epithelial tumors including oral squamous cell carcinoma (OSCC), a common malignancy of the head and neck. However, the functional role of the actin-sequestering protein thymosin β4 (Tβ4) in the EMT in OSCCs remains unclear. Thus, we investigated whether overexpression of Tβ4 could induce in vitro tumorigenesis such as cell proliferation and anchorage independency and an EMT-like phenotype in OSCCs.

The Effect of a Combination of Implant Controller and Handpiece from Different Manufacturers on the Torque Value.

Purpose: To determine the accuracy of applied torque of different implant controller and handpiece combinations by using an electronic torque gauge.

Materials And Methods: Four combinations of the following devices were tested: Surgic XT controller (NSK), XIP10 controller (Saeshin), X-SG20L handpiece (NSK), CRB26LX handpiece (Saeshin). For five torque settings, 30 measurements were recorded at 30 revolutions per minute by using an electronic torque gauge fixed to jigs, and means were calculated.

Chondrosarcoma of the temporomandibular joint: a case report and review of the literature.

Objective: Chondrosarcoma is the second most common sarcoma arising in the bone, but it rarely involves the temporomandibular joint (TMJ). To date, 30 cases of TMJ chondrosarcoma have been reported in the English literature, and the authors report an additional case arising from a cystic lesion in a 60-year-old female patient.

Clinical Presentation: The clinical and radiological diagnosis of the lesion was initially synovial cyst, and periodic check-ups were done after aspiration of the lesion.

The potential of interleukin 12 receptor beta 2 (IL12RB2) and tumor necrosis factor receptor superfamily member 8 (TNFRSF8) gene as diagnostic biomarkers of oral lichen planus (OLP).

Objective: This study evaluated the potential of interleukin 12 receptor beta 2 and tumor necrosis factor receptor superfamily member 8 as diagnostic biomarkers of oral lichen planus (OLP).

Materials And Methods: The mRNA expression of IL12RB2 and TNFRSF8 in FFPE OLP samples (OLP group, n = 38) were investigated with quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) analysis and compared to those of chronic non-specific mucositis (Non-OLP group, n = 25) and normal mucosa (Normal group, n = 18). Predictive modeling of the expression of IL12RB2 and TNFRSF8 was constructed using support vector machine (SVM), random forest (RF), linear discriminant analysis (LDA), neural network (NN) and naive Bayes (NB) methods.

Geometric and electronic structure and magnetic properties of Fe-Au nanoalloys: insights from ab initio calculations.

We have performed density functional theory (DFT) based calculations of Fe-Au nanoalloys containing 113 atoms, Fe(x)Au(113-x) (x = 23, 56, 90), to determine their preferred geometric structure and the ensuing electronic structural and magnetic properties. We find that these nanoalloys prefer the formation of a core-shell structure and the Fe core maintains almost a constant magnetic moment of ∼2.8 μ(B) regardless of the Fe content, which is 27% enhancement from the bulk value and in qualitative agreement with some previous results.

Geriatric oral lesions: A multicentric study.

Aim: To carry out an oral biopsy survey in geriatric patients from the participating institutions.

Methods: The biopsy records of the participating institutions were reviewed for oral lesions from patients aged 65 years and older diagnosed from 2003 to 2012. Demographic data and the site of the lesions were collected.

The role of p300 in the tumor progression of oral squamous cell carcinoma.

Background: EP300 gene encoding p300 is a candidate tumor suppressor gene. This study investigated p300 expression and gene alteration in oral squamous cell carcinoma (OSCC) specimens to assess its role in OSCC development.

Methods: Genomic DNA extracted from 13 human OSCC cell lines and 40 OSCC patient specimens was subjected to methylation-specific PCR and exon sequencing.

Structural and electronic properties of micellar Au nanoparticles: size and ligand effects.

Gaining experimental insight into the intrinsic properties of nanoparticles (NPs) represents a scientific challenge due to the difficulty of deconvoluting these properties from various environmental effects such as the presence of adsorbates or a support. A synergistic combination of experimental and theoretical tools, including X-ray absorption fine-structure spectroscopy, scanning transmission electron microscopy, atomic force microscopy, and density functional theory was used in this study to investigate the structure and electronic properties of small (∼1-4 nm) Au NPs synthesized by an inverse micelle encapsulation method. Metallic Au NPs encapsulated by polystyrene 2-vinylpiridine (PS-P2VP) were studied in the solution phase (dispersed in toluene) as well as after deposition on γ-Al2O3.

Plasmablastic lymphoma of the oral cavity in a human immunodeficiency virus-negative patient: a case report with literature review.

Plasmablastic lymphoma (PBL) is an aggressive diffuse large B-cell lymphoma variant that is most frequently observed in the oral cavity of human immunodeficiency virus (HIV)-infected individuals. However, in recent years, some cases have emerged in patients without HIV infection and involve other sites like stomach, lung, nasal cavity, and jejunum. We report a rare case of PBL in the maxillary anterior area of a 62-year-old man without HIV infection.

Hypothetical pathogenesis of eosinophilic infiltration in Langerhans cell histiocytosis of the jaw.

Objective: The present study investigated the densities of mast cells and CCL-11/eotaxin-1 expression of tumor cells in Langerhans cell histiocytosis (LCH) of the jaw.

Study Design: Eleven LCH cases arising in the jaws were selected. We evaluated eotaxin-1 expression in LCH cells via immunohistochemical staining.

Rationale for the higher reactivity of interfacial sites in methanol decomposition on Au13/TiO2(110).

Interfacial and perimeter sites have been known for their high activity in various reactions on supported gold nanoparticles. We find that the higher activity of interfacial sites in Au13/TiO2(110) toward methanol decomposition originates from charge-transfer-induced Coulomb interaction among the gold, reactant, and reducible TiO2 support, brought about through the formation of an ionic O-Au bond between gold and methoxy in such sites, which turns the participating perimeter gold atom cationic. A direct result of such charge-transfer-induced repulsive interaction between cationic gold and positively charged C moiety of methoxy is activation of the positively charged C moiety of methoxy, as manifested by the pronounced elongation of O-C bond length and the tilting of the methoxy axis, which facilitate reaction of methoxy through C-H scission with the bridge oxygen atoms that are readily available from the reducible support.

A giant radiopaque mass in the masticatory space.

A 2-year-old boy presented with a giant mass in the masticatory space. The mass exhibited a lobulating ossification, with no attachment to the adjacent normal bone. An enucleation was performed under the tentative diagnosis of extra-articular synovial chondromatosis, benign ossifying neoplasm, non-neoplastic heterotopic ossification, or low-grade malignancy.

Histopathological features of bisphosphonate-associated osteonecrosis: findings in patients treated with partial mandibulectomies.

The present study investigated the histopathologic and radiographic features of stage 3 bisphosphonate-associated osteonecrosis of the jaw (BAONJ) in patients who were treated with partial mandibulectomies. Bisphosphonates had been orally administered to 10 patients with osteoporosis and intravenously administered to 1 patient with metastatic carcinoma. On radiographic images, massive osteolysis and periosteal bone formations were conspicuous, and a thin mandibular cortical width was observed in 5 of 10 osteoporosis patients despite the previous use of bisphosphonate.

Comparative immunohistochemical study of ameloblastoma and ameloblastic carcinoma.

Objective: Ameloblastic carcinoma combines the histologic features of ameloblastoma with cytologic atypia, regardless of whether it has metastasized. Because of its rarity, there are few immunoprofile studies of ameloblastic carcinoma and few comparative studies of ameloblastic carcinoma and ameloblastoma. In this study, we compared the expression levels of cytokeratins (CKs), matrix metalloproteinases (MMPs), and Ki-67 between ameloblastoma and ameloblastic carcinoma, and assessed the usefulness of these markers for differentiating the tumors.

Relationship between the expressions of PD-L1 and tumor-infiltrating lymphocytes in oral squamous cell carcinoma.

Tumor-infiltrating lymphocytes (TILs) are considered to represent immune reactions of the host to a malignant tumor. Programmed death receptor ligand-1 (PD-L1) is a surface protein that blocks the function of T lymphocytes and is expressed on cancer cells. Tumor-associated fibroblasts (TAFs), which influence tumor growth have also been reported to express PD-L1 and thus inhibit TILs.

The role of Cripto-1 in the tumorigenesis and progression of oral squamous cell carcinoma.

Oral squamous cell carcinoma (OSCC), the most common malignancy of the oral cavity, remains a lethal disease in over 50% of cases diagnosed annually, due mostly to late detection of this cancer in its advanced stages despite the easy accessibility of the oral cavity for regular examinations. Cripto-1 is a member of the epidermal growth factor (EGF)-CFC protein family and is involved in the activation of several different signaling pathways during embryonic development and cellular transformation. Although the Cripto-1 protein is overexpressed in several human cancers including breast, colon, cervix, gastric, and pancreatic cancer, no prior study has evaluated Cripto-1 expression in OSCC.

Malignant pigmented villonodular synovitis of the temporomandibular joint with lung metastasis: a case report and review of the literature.

Malignant pigmented villonodular synovitis (PVNS) is an extremely rare lesion. Approximately 30 cases of malignant PVNS have been reported to date and of these, only 1 case involved the temporomandibular joint. Owing to the rarity of well-documented cases and the heterogeneous histologic features of this group of tumors, there has been some confusion regarding its diagnosis.

Multiple calcifying hyperplastic dental follicles: comparison with hyperplastic dental follicles.

Background: Multiple calcifying hyperplastic dental follicles (MCHDF) is a rare disorder that is characterized by multiple impacted teeth and enlarged dental follicles that include calcifications. The current lack of information characterizing MCHDF impedes clinicians from making prompt differential diagnoses. We describe five cases of MCHDF and analyze their clinical and histopathological features in an effort to compare MCHDF with hyperplastic dental follicles (HDF) of singly impacted teeth.