Miniversal deformations of chains of linear mappings

V.I. Arnold [Russian Math. Surveys, 26 (no. 2), 1971, pp. 29–43] gave a miniversal deformation of matrices of linear operators; that is, a simple canonical form, to which not only a given square matrix A, but also the family of all matrices close to A, can be reduced by similarity transformations smoothly depending on the entries of matrices. We study miniversal deformations of quiver representations and obtain a miniversal deformation of matrices of chains of linear mappings V₁ V₂ · · · Vt , where all Vi are complex or real vector spaces and each line denotes −→ or ←−

MALT-lymphomas in Sjogren's disease

Aim. To develop algorithm of early diagnosis of extranodal lymphoma arising in patients with Sjorgen's disease (SD). Material and methods. SD diagnosis was made in 457 patients treated in Rheumatology Institute clinic in 1999-2004, 38 (8.3%) females aged 19-82 had lymphoproliferative diseases. MAL T-lymphomas were diagnosed in 15 (42.2%) patients. All the patients have undergone morphological, immunomorphological investigations of the salivary glands, postoperative material was analysed in some patients. In addition, the following investigations were made: ultrasonography of the salivary glands, lymph nodes, viscera; scintigraphy; trephine biopsy of the bone marrow; myelograms; CT of the chest, abdomena and brain; tests for monoclonal immunoglobulins in the serum and light chains in urine, biopsy of the parotid gland. Clinical, morphological and immunophenotypical characteristics of MALT-lymphomas were assessed by WHO classification. Lymphoma stages were classified according to Ann Arbor. Results. Parotid glands were affected with MALT-lymphoma most frequently. Predominant were extranodal lymphomas of the parotid submandibular, minor salivary glands of the lip and lacrimal glands of stage IE-II E. Extranodal lymphoma with nodal lesion of stage IV occurred less frequently. Untreated long existing MALT-lymphomas of the parotid glands may transform into B-large cell lymphomas deteriorating SD prognosis. The presence of long-term (> 12 months) massive enlargement of parotid/submandibular salivary and lacrimal glands, massive infiltration, monoclonal immunoglobulins in blood serum and their light chains in the urine predict development of MALT-lymphoma in SD. Conclusion. In SD, MALT-lymphomas develop primarily in target organs - salivary and lacrimal glands. SD patients with persistent enlargement of the parotid glands need biopsy for early detection of malignant lymphoproliferation

MALT-lymphomas in Sjogren's disease

Aim. To develop algorithm of early diagnosis of extranodal lymphoma arising in patients with Sjorgen's disease (SD). Material and methods. SD diagnosis was made in 457 patients treated in Rheumatology Institute clinic in 1999-2004, 38 (8.3%) females aged 19-82 had lymphoproliferative diseases. MAL T-lymphomas were diagnosed in 15 (42.2%) patients. All the patients have undergone morphological, immunomorphological investigations of the salivary glands, postoperative material was analysed in some patients. In addition, the following investigations were made: ultrasonography of the salivary glands, lymph nodes, viscera; scintigraphy; trephine biopsy of the bone marrow; myelograms; CT of the chest, abdomena and brain; tests for monoclonal immunoglobulins in the serum and light chains in urine, biopsy of the parotid gland. Clinical, morphological and immunophenotypical characteristics of MALT-lymphomas were assessed by WHO classification. Lymphoma stages were classified according to Ann Arbor. Results. Parotid glands were affected with MALT-lymphoma most frequently. Predominant were extranodal lymphomas of the parotid submandibular, minor salivary glands of the lip and lacrimal glands of stage IE-II E. Extranodal lymphoma with nodal lesion of stage IV occurred less frequently. Untreated long existing MALT-lymphomas of the parotid glands may transform into B-large cell lymphomas deteriorating SD prognosis. The presence of long-term (> 12 months) massive enlargement of parotid/submandibular salivary and lacrimal glands, massive infiltration, monoclonal immunoglobulins in blood serum and their light chains in the urine predict development of MALT-lymphoma in SD. Conclusion. In SD, MALT-lymphomas develop primarily in target organs - salivary and lacrimal glands. SD patients with persistent enlargement of the parotid glands need biopsy for early detection of malignant lymphoproliferation