Recurrent bilateral gingival peripheral calcifying epithelial odontogenic tumor (Pindborg tumor): A case report

Calcifying epithelial odontogenic tumor (CEOT) is an extremely rare, benign neoplasm, accounting for approximately 1% of all odontogenic tumors. Peripheral CEOTs commonly resemble oral hyperplastic or reactive lesions and are histologically similar to their intraosseous counterparts. We report an unusual case of multifocal peripheral CEOT. A 40-year-old female presented with bilateral soft, painful, erythematous, gingival swellings localized in premolar areas of the mandibular gingiva. The presumptive diagnosis was bilateral pyogenic granuloma. The masses were surgically excised under local anesthesia without bone curettage and both recurred 12 months later. Morphologic features, and histochemical and immunohistochemical tests revealed bilateral peripheral calcifying odontogenic epithelial tumor. There is no clinical or radiographic evidence of recurrence 3.5 years after excision. This multifocal phenomenon has been reported previously only for intraosseous CEOT. Gingival masses must be carefully evaluated for clinical and histologic evidence of neoplasia. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2009; 108: e66-e71)

Patients with oral squamous cell carcinoma are characterized by increased frequency of suppressive regulatory T cells in the blood and tumor microenvironment

Oral squamous cell carcinoma (OSCC) is a cancerous lesion with high incidence worldwide. The immunoregulatory events leading to OSCC persistence remain to be elucidated. Our hypothesis is that regulatory T cells (Tregs) are important to obstruct antitumor immune responses in patients with OSCC. In the present study, we investigated the frequency, phenotype, and activity of Tregs from blood and lesions of patients with OSCC. Our data showed that > 80% of CD4(+)CD25(+) T cells isolated from PBMC and tumor sites express FoxP3. Also, these cells express surface Treg markers, such as GITR, CD45RO, CD69, LAP, CTLA-4, CCR4, and IL-10. Purified CD4(+)CD25(+) T cells exhibited stronger suppressive activity inhibiting allogeneic T-cell proliferation and IFN-gamma production when compared with CD4(+)CD25(+) T cells isolated from healthy individuals. Interestingly, approximately 25% of CD4(+)CD25(-) T cells of PBMC from patients also expressed FoxP3 and, although these cells weakly suppress allogeneic T cells proliferative response, they inhibited IFN-gamma and induced IL-10 and TGF-beta secretion in these co-cultures. Thus, our data show that Treg cells are present in OSCC lesions and PBMC, and these cells appear to suppress immune responses both systemically and in the tumor microenvironment.

Polysaccharide fraction of Agaricus brasiliensis avoids tumor-induced IL-10 production and changes the microenvironment of subcutaneous Ehrlich adenocarcinoma

Subcutaneous Ehrlich tumor-bearing mice were treated with in situ inoculation of a P-glucan-rich extract of Agaricus brasiliensis (ATF), which reduced tumor growth. Histopathological analysis showed that the tumor masses of control mice (Ehr) presented giant tumor cells and many mitotic figures whereas the tumor tissue obtained from ATF-treated animals (Ehr-ATF) presented a lower frequency of both mitotic and giant cells, associated with a higher frequency of apoptotic cells than Ehr. Analysis of the lymphoproliferative activity of spleen cells showed that the treatment had a suppressive rather than a stimulatory effect. Spleen cells of the Ehr group produced higher in vitro levels of IL-10 than normal controls and this occurrence was partially avoided by treatment with ATF. Analysis of cytokine production by tumor-infiltrating cells (ELISpot) showed that ATF induced a higher number of IFN-gamma-producing cells at 7 and 14 days as well as reduction of IL-10-secreting cells at the latter time. Confocal microscopy analysis showed higher intensity of labeling of CD4+ and Mac-3+ cells in ATF-treated mice. Analysis of in situ expression of angiogenic growth factors showed a slight decrease of FGF-2 mRNA in Ehr-ATF animals (7th day) but not of VEGF-A or TGF-beta expression. This fraction could not directly lyse either lymphocytes or tumor cells and we speculate that antitumor effect of ATF could be due to induction of a selective migration of immunocompetent cells from the spleen to the tumor site and to the switch of cytokine production. (C) 2009 Elsevier Inc. All rights reserved.

Warthin Tumor of the Upper Lip: An Unusual Location of a Benign Salivary Gland Tumor

Warthin tumor (papillary cystadenoma lymphomatosum) is a benign salivary gland tumor involving almost exclusively the parotid gland. The lip is a very unusual location for this type of tumor, which develops only rarely in minor salivary glands. The case of 42-year-old woman with Warthin tumor arising in minor salivary glands of the upper lip is reported.

Integrable extended hubbard models with boundary Kondo impurities

Three kinds of integrable Kondo impurity additions to one-dimensional q-deformed extended Hubbard models are studied by means of the boundary Z(2)-graded quantum inverse scattering method. The boundary K matrices depending on the local magnetic moments of the impurities are presented as nontrivial realisations of the reflection equation algebras in an impurity Hilbert space. The models are solved by using the algebraic Bethe ansatz method, and the Bethe ansatz equations are obtained.

Exact solution for the Bariev model with boundary fields

The Bariev model with open boundary conditions is introduced and analysed in detail in the framework of the Quantum Inverse Scattering Method. Two classes of independent boundary reflecting K-matrices leading to four different types of boundary fields are obtained by solving the reflection equations. The models are exactly solved by means of the algebraic nested Bethe ansatz method and the four sets or Bethe ansatz equations as well as their corresponding energy expressions are derived. (C) 2001 Elsevier Science B.V. All rights reserved.

Precursor scavenging of the resistive grain-boundary phase in 8 mol% yttria-stabilized zirconia: Effect of trace concentrations of SiO2

The influence that trace concentrations Of SiO2 have on improving grain-boundary conduction via precursor scavenging using additional heat treatment at 1200 degreesC for 40 h before sintering was investigated. At a SiO2-impurity level (SIL) less than or equal to 160 ppm by weight, the grain-boundary resistivity (p(gb)) decreased to 20% of its value, while no improvement in grain-boundary conduction was found at a SIL greater than or equal to 310 ppm. The correlation between the resistance per unit grain-boundary area, p(gb), and average grain size indicated that the inhomogeneous distribution of the siliceous phase in the sample with a SIL greater than or equal to 310 ppm. hampered the scavenging reaction.

Izergin-Korepin model with a boundary

The Izergin-Korepin model on a semi-infinite lattice is diagonalized by using the level-one vertex operators of the twisted quantum affine algebra U-q[((2))(2)]. We give the bosonization of the vacuum state with zero particle content. Excitation states are given by the action of the vertex operators on the vacuum state. We derive the boundary S-matrix. We give an integral expression of the correlation functions of the boundary model, and derive the difference equations which they satisfy. (C) 2001 Elsevier Science B.V. All rights reserved.

Three-point boundary value problems for second-order, ordinary, differential equations

We establish existence results for solutions to three-point boundary value problems for nonlinear, second-order, ordinary differential equations with nonlinear boundary conditions. (C) 2001 Elsevier Science Ltd. All rights reserved.

Topological methods for some boundary value problems

We establish existence of solutions for a finite difference approximation to y = f(x, y, y ') on [0, 1], subject to nonlinear two-point Sturm-Liouville boundary conditions of the form g(i)(y(i),y ' (i)) = 0, i = 0, 1, assuming S satisfies one-sided growth bounds with respect to y '. (C) 2001 Elsevier Science Ltd. All rights reserved.

Electron beam current loss at the high-vacuum-high-pressure boundary in the environmental scanning electron microscope

A significant loss in electron probe current can occur before the electron beam enters the specimen chamber of an environmental scanning electron microscope (ESEM). This loss results from electron scattering in a gaseous jet formed inside and downstream (above) the pressure-limiting aperture (PLA), which separates the high-pressure and high-vacuum regions of the microscope. The electron beam loss above the PLA has been calculated for three different ESEMs, each with a different PLA geometry: an ElectroScan E3, a Philips XL30 ESEM, and a prototype instrument. The mass thickness of gas above the PLA in each case has been determined by Monte Carlo simulation of the gas density variation in the gas jet. It has been found that the PLA configurations used in the commercial instruments produce considerable loss in the electron probe current that dramatically degrades their performance at high chamber pressure and low accelerating voltage. These detrimental effects are minimized in the prototype instrument, which has an optimized thin-foil PLA design.

Integrable open boundary conditions for the Bariev model of three coupled X Y spin chains

The integrable open-boundary conditions for the Bariev model of three coupled one-dimensional XY spin chains are studied in the framework of the boundary quantum inverse scattering method. Three kinds of diagonal boundary K-matrices leading to nine classes of possible choices of boundary fields are found and the corresponding integrable boundary terms are presented explicitly. The boundary Hamiltonian is solved by using the coordinate Bethe ansatz technique and the Bethe ansatz equations are derived. (C) 2001 Elsevier Science B.V. All rights reserved.