Gauge Theories Coupled to Fermions in Generation

Gauge theories coupled to fermions in generation are reformulated in a modified version of extended differential geometry with the symbol $\chi$. After discussing several toy models, we will reformulate in our framework the standard model based on Connes' real structure. It is shown that for the most general bosonic lagrangin which is required to also reconstruct N=2 super Yang-Mills theory Higgs mechanism operates only for more than one generation as first pointed out by Connes and Lott.Comment: 18 pages, ptptex.st

Lagrangian Formulation of Connes' Gauge Theory

It is shown that Connes' generalized gauge field in non-commutative geometry is derived by simply requiring that Dirac lagrangian be invariant under local transformations of the unitary elements of the algebra, which define the gauge group. The spontaneous breakdown of the gauge symmetry is guaranteed provided the chiral fermions exist in more than one generations as first observed by Connes-Lott. It is also pointed out that the most general gauge invariant lagrangian in the bosonic sector has two more parameters than in the original Connes-Lott scheme.Comment: 9 pages, PTPTEX.st

Lorentz-Invariant Non-Commutative Space-Time Based On DFR Algebra

It is argued that the familiar algebra of the non-commutative space-time with $c$-number $\theta^{\mu\nu}$ is inconsistent from a theoretical point of view. Consistent algebras are obtained by promoting $\theta^{\mu\nu}$ to an anti-symmetric tensor operator ${\hat\theta}^{\mu\nu}$. The simplest among them is Doplicher-Fredenhagen-Roberts (DFR) algebra in which the triple commutator among the coordinate operators is assumed to vanish. This allows us to define the Lorentz-covariant operator fields on the DFR algebra as operators diagonal in the 6-dimensional $\theta$-space of the hermitian operators, ${\hat\theta}^{\mu\nu}$. It is shown that we then recover Carlson-Carone-Zobin (CCZ) formulation of the Lorentz-invariant non-commutative gauge theory with no need of compactification of the extra 6 dimensions. It is also pointed out that a general argument concerning the normalizability of the weight function in the Lorentz metric leads to a division of the $\theta$-space into two disjoint spaces not connected by any Lorentz transformation so that the CCZ covariant moment formula holds true in each space, separately. A non-commutative generalization of Connes' two-sheeted Minkowski space-time is also proposed. Two simple models of quantum field theory are reformulated on $M_4\times Z_2$ obtained in the commutative limit.Comment: LaTeX file, 27 page

A Field-Theoretic Approach to Connes' Gauge Theory on M4×Z2M_4\times Z_2

Connes' gauge theory on $M_4\times Z_2$ is reformulated in the Lagrangian level. It is pointed out that the field strength in Connes' gauge theory is not unique. We explicitly construct a field strength different from Connes' one and prove that our definition leads to the generation-number independent Higgs potential. It is also shown that the nonuniqueness is related to the assumption that two different extensions of the differential geometry are possible when the extra one-form basis $\chi$ is introduced to define the differential geometry on $M_4\times Z_2$. Our reformulation is applied to the standard model based on Connes' color-flavor algebra. A connection between the unimodularity condition and the electric charge quantization is then discussed in the presence or absence of $\nu_R$.Comment: LaTeX file, 16 page

Diagnostic efficacy of cell block method for vitreoretinal lymphoma

Background: Vitreoretinal lymphoma (VRL) is a life- and sight-threatening disorder. The aim of this study was to analyze the usefulness of the cell block method for diagnosis of VRL. Methods: Sixteen eyes in 12 patients with VRL, and 4 eyes in 4 patients with idiopathic uveitis presenting with vitreous opacity were enrolled in this study. Both undiluted vitreous and diluted fluids were isolated during micro-incision vitrectomy. Cell block specimens were prepared in 19 eyes from diluted fluid containing shredding vitreous. These specimens were then submitted for HE staining as well as immunocytological analyses with antibodies against the B-cell marker CD20, the T-cell marker CD3, and cell proliferation marker Ki67. Conventional smear cytology was applied in 14 eyes with VRL using undiluted vitreous samples. The diagnosis of VRL was made based on the results of cytology, concentrations of interleukin (IL)-10 and IL-6 in undiluted vitreous, and immunoglobulin heavy chain gene rearrangement analysis. Results: Atypical lymphoid cells were identified in 14 out of 15 cell block specimens of VRL (positive rate: 93.3 %), but in 5 out of 14 eyes in conventional smear cytology (positive rate: 35.7 %). Atypical lymphoid cells showed immunoreactivity for CD20 and Ki67. Seven cell block specimens were smear cytology-negative and cell block-positive. The cell block method showed no atypical lymphoid cells in any patient with idiopathic uveitis. Conclusions: Cell block specimens using diluted vitreous fluid demonstrated a high diagnostic sensitivity and a low pseudo-positive rate for the cytological diagnosis of VRL. The cell block method contributed to clear differentiation between VRL and idiopathic uveitis with vitreous opacity.背景：眼内リンパ腫（VRL）は視力・生命予後に影響を及ぼす疾患である。本研究ではVRLの診断における細胞塊（セルブロック）標本の有用性を検討することを目的とした。症例と方法：北海道大学病院眼科および他院を受診したVRL12例16眼、および硝子体混濁を呈した特発性ぶどう膜炎4例4眼を対象とした。小切開硝子体手術により、無希釈硝子体液および硝子体灌流液を採取した。19眼で、硝子体灌流液を用いたセルブロック標本を作製した。これらの標本を用いて特殊染色、およびB細胞マーカーである抗CD20抗体の免疫細胞化学的検討を行った。14眼では無希釈硝子体液を用いた塗抹細胞診を併せて行った。VRLの診断は、細胞診、無希釈硝子体液のIL-10, -6濃度、灌流液沈殿物から遺伝子再構成部位のモノクローナリティについて検討して行った。結果：VRLの15眼中14眼でセルブロック標本にて悪性リンパ腫細胞が検出された（陽性率：93.3％）。一方、塗抹細胞診では5眼で悪性細胞が検出された（陽性率：35.7％）。塗抹細胞診で陰性、セルブロックで陽性を示したIOL症例は7例8眼であった。特発性ぶどう膜炎では、悪性細胞が検出された症例はなかった（陽性率：0％）。VRL細胞はCD20陽性を示したが、特発性ぶどう膜炎ではCD20陽性細胞は検出されなかった。結語：硝子体灌流液を用いたセルブロック細胞診は、これまでの塗抹細胞診よりVRLの陽性率が高く、偽陽性も無かった。セルブロックは、VRLとぶどう膜炎との鑑別にも有用であることが示唆された

Cytopathologic findings of cell block materials from the vitreous : Diagnostic distinction between intraocular lymphoma and non-lymphomatous diseases

Intraocular lymphoma is a rare neoplasm that occurs only in the eyes and/or central nervous system. Diagnosis of intraocular lymphoma is difficult because its clinical manifestations mimic chronic uveitis. Pathological examination of the vitreous is one of the main diagnostic tools for intraocular lymphoma, but this is challenging due to the sparse cellularity and specimen degeneration. Here, we reviewed 33 cell block preparations from vitreous perfusion fluid in order to examine the significance of cytopathological findings for differential diagnosis using vitreous samples. The cases comprised 12 intraocular lymphomas and 21 non-lymphomatous diseases. Cytologically, vitreous samples from non-lymphoma cases showed lower cellularity than the lymphoma cases. Whereas vitreous material from cases with infectious endophthalmitis showed prominent neutrophilic infiltration, material from sarcoidosis cases showed infiltration of small lymphoid cells, especially CD4-positive T cells. On the other hand, lymphoma cases showed higher cellularity, with large, irregular and atypical lymphoid cells, frequent necrotic cells in the background, and less pronounced neutrophil infiltration. Immunocytochemically, 11 of the 12 lymphoma cases were of the B-cell phenotype and the remaining case was of the T/NK-cell phenotype. In conclusion, careful cytopathological examination or immunocytochemistry of vitreous material facilitates appropriate diagnosis of intraocular lymphoma

Usefulness of PET/CT for early detection of internal malignancies in patients with Muir-Torre syndrome : report of two cases

Background: Muir-Torre syndrome (MTS) is a rare autosomal dominant genodermatosis caused by mutations in mismatch repair genes. It is characterized by the presence of at least one sebaceous skin tumor associated with internal malignancies. Whether positron emission tomography/computed tomography (PET/CT) is useful for the detection of malignancies in patients with MTS has not been determined. We herein report two cases in which PET/CT was useful for the diagnosis and follow-up of internal malignancies in patients with MTS. Case presentation: In case 1, a 57-year-old woman underwent excision of a sebaceous carcinoma on the left upper eyelid. She underwent follow-up PET/CT once yearly thereafter. Forty-two months after the eyelid surgery, PET/CT showed intense tracer uptake in the right lower abdomen. An ascending colon tumor was identified, and examination of a biopsy specimen showed adenocarcinoma. In case 2, a 77-year-old man presented for evaluation of three continuous papules with telangiectasia on his right cheek. Examination of a skin biopsy specimen of the cheek papule revealed a sebaceous carcinoma. He underwent PET/CT to detect other malignancies. PET/CT showed intense tracer uptake in the sigmoid colon. A sigmoid colon tumor was identified, and examination of a biopsy specimen showed adenocarcinoma. Both patients underwent resection of their tumors, and both were still free of recurrence of the sebaceous and colon carcinomas at the time of this writing. Conclusion: PET/CT is a reliable imaging modality for the detection of internal malignancies and is useful for the diagnosis and follow-up of MTS