Pulmonary metastasis of matrix-producing carcinoma mimicking small cell lung cancer.

Matrix-producing carcinoma (MPC) of the breast is an extremely rare subtype of invasive breast cancer. MPC is characterized by the production of a cartilaginous or osseous matrix without spindle cells. It is an aggressive carcinoma, often presenting as triple-negative breast cancer. MPC frequently metastasizes to the lungs; however, it rarely reoccurs as a solitary pulmonary metastasis. We report a case of a 77-year-old non-smoking woman with a solitary pulmonary metastasis of MPC, which mimicked small cell lung cancer (SCLC). Initially, the pulmonary metastasis was misdiagnosed as SCLC based on its morphological and immunochemical features, including focal positivity for CD56 and thyroid transcription factor-1. Although the portion of the chondromyxoid matrix of the primary site was not small, that of the metastatic site was small. A focal cartilaginous matrix deposition of pulmonary metastasis from MPC could make it difficult to differentiate from SCLC. We should acknowledge that the portion of chondromyxoid matrix may differ between primary and distant metastatic sites in MPC.

Thymoma exhibiting spontaneous regression with developing myasthenia gravis: A case report.

Spontaneous regression (SR) of thymoma is rare. A 44-year-old man with right chest pain underwent computed tomography (CT), which showed an 11.0 cm mass in the anterior mediastinum and right pleural effusion. He refused surgery and was sent home without medication and additional treatment. One year later, the mass had regressed to 5.5 cm, and the right pleural effusion had disappeared. He was then lost to follow-up. Four years after the initial visit, he presented with diplopia and fatigue. A significant increase in his anti-acetylcholine receptor antibody levels led to myasthenia gravis (MG) diagnosis. CT revealed a regressed mediastinal mass (3.0 cm). After extended thymectomy, histologic analysis confirmed a thymoma type B2, Masaoka stage IIa. The SR was due to intratumoral infarction. This report is the first to describe MG developing during SR. Anterior mediastinal tumors undergoing SR should be differentiated from thymomas and MG perioperative development should be considered.

Identification, Characterization, and X-ray Crystallographic Analysis of a Novel Type of Lectin AJLec from the Sea Anemone Anthopleura japonica.

A novel galactose-specific lectin, AJLec (18.5 kDa), was isolated from the sea anemone, Anthopleura japonica. AJLec was characterized using the hemagglutination assay, isothermal titration calorimetry (ITC), and glycoconjugate microarray analysis and we found that AJLec has a specificity for galactose monomers and ß-linked terminal galactose residues in complex carbohydrates, but not for N-acetylgalactosamine (GalNAc), which is commonly recognized by galactose-binding lectins. The primary structure of AJLec did not show homology with known lectins, and a crystal structural analysis also revealed a unique homodimeric structure. The crystal structure of AJLec complexed with lactose was solved by measuring the sulfur single-wavelength anomalous diffraction (S-SAD) phasing with an in-house Cu Kα source method. This analysis revealed that the galactose residue in lactose was recognized via its O2, O3, and O4 hydroxyl groups and ring oxygen by calcium coordination and two hydrogen bonds with residues in the carbohydrate-binding site, which demonstrated strict specificity for the ß-linked terminal galactose in this lectin.

A New Flavonoid from Camellia sinensis Fermented Tea.

A new flavonoid, quercetin 3-0-α-L-rhamnopyranosyl-(l-6)-(2-E-p-coumaroyl)-D-D-glucopyranoside-4'-O-α-L-rhamnopyranoside, was isolated from the fermented tea of Camellia sinensis L. (Pu-erh tea) from China. The chemical structure was elucidated based on analyses of the spectroscopic data.