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Diagnosis of gastrointestinal (GI) amyloidosis is often very difficult because of its nonspecific symptoms. However, a few reports have indicated that serious symptoms such as fatal GI bleeding and obstruction or perforation sometimes lead to a diagnosis of GI amyloidosis. A 79-year-old man was transported to our emergency department with a 1-week history of worsening abdominal pain. Abdominal contrast-enhanced computed tomography showed extravasation from part of the transverse colon wall and moderate ascites. Because intra-abdominal bleeding was suspected, the patient urgently underwent partial resection of the transverse colon, which was the source of the bleeding. Postoperative pathological examination of the tissue specimens led to a diagnosis of amyloid transthyretin amyloidosis. This is the first reported case in which intra-abdominal bleeding led to a diagnosis of GI amyloidosis. We should consider the possibility of GI amyloidosis when intraperitoneal bleeding is observed in elderly patients. [ABSTRACT FROM AUTHOR]

Salivary duct carcinoma with rhabdoid features (SDCRF) is a rare salivary tumor with poor prognosis and is proposed as a salivary counterpart of pleomorphic lobular carcinoma of the breast (PLCB). Here, we report three cases of SDC with rhabdoid features (SDCRF) mimicking PLCB. Pleomorphic adenoma (PA) component was accompanied in all the cases confirming carcinoma ex PA. One patient had frequent rhabdoid features and showed invasive growth into the surrounding tissue. The other two patients had intracapsular tumor but with rhabdoid features. The patients with intracapsular SDCRF survived for > 5 years after surgery with no evidence of recurrence, whereas the patient with extracapsular SDCRF died 10 months after biopsy, and autopsy revealed disseminated metastasis to the central nervous system. Histologically, tumor cells in all three cases resembled PLCB, with a discohesive appearance, abundant cytoplasm, enlarged hyperchromatic nuclei, and similar immunohistochemical profiles, namely loss of membranous E-cadherin, obscured expression of membranous β-catenin, diffuse positivity of androgen receptor, gross cystic disease fluid protein-15, mitochondrial adenosine triphosphate synthase subunit β, MUC1, and INI-1. Estrogen and progesterone receptors were negative, and HER2 immunoreactivities were variable. The tumor cells of extracapsular invasive SDCRF exhibited higher MIB-1 labeling index and more frequent intracytoplasmic lumina than those of intracapsular SDCRF. Ultrastructurally, rhabdoid cells contained intracytoplasmic lumina with microvillous structure, analogous to those reported in PLCB. No intracytoplasmic intermediate filament aggregation was observed. These observations indicate that SDCRF is a salivary counterpart of PLCB and under signet ring cell differentiation. [ABSTRACT FROM AUTHOR]

Background: Oral administration of lysophosphatidic acid (LPA) was shown to attenuate gastric ulceration in rats and mice but aggravate intestinal tumorigenesis in mice.Aims: The present study examined whether dietary LPA induces or prevents development of colorectal tumor in rats.Methods: Kyoto Apc Delta rats fed high-fat diet with or without an LPA-rich soybean phospholipid mixture (LSP, 0.1 or 1%) were treated with azoxymethane and dextran sodium sulfate to induce colorectal tumorigenesis. Rats were killed 15 weeks after azoxymethane treatment, and size, total number, location, and severity of colorectal tumors were assessed. Expression of mRNA of LPA receptors in rat colon tissue was assayed.Results: Rats fed the diet supplemented with 1% LSP had a higher number of tumors 2-4 mm long compared than those with or without 0.1% LSP. The mean distance of tumors >4 mm long from the anus was significantly higher than those of tumors <2 and 2-4 mm long in rats fed 1% LSP-supplemented diet. Supplementation of the diet with 0.1% LSP decreased mRNA expression of LPA5 in colon tumors of rats.Conclusions: Dietary supplementation of LPA-rich phospholipids dose-dependently augmented colorectal tumorigenesis. Decreased expression of LPA5 in colon tumors may be relevant to augmented tumorigenesis. [ABSTRACT FROM AUTHOR]

Background: Little information is available on the precise mechanisms leading to the development of acute gastric mucosal lesions (AGMLs). We investigated whether the pathologic mechanism of AGMLs resulting in damage to epithelial cells is associated with cytotoxic molecules expressed by activated intraepithelial lymphocytes (IELs). Methods: The expression of the lymphocyte markers, CD3, CD4, CD8, CD20, T-cell-restricted intracellular antigen (TIA)-1, and granzyme B (GrB)-7 in IELs and that of single-stranded DNA (ssDNA) in apoptotic epithelial cells were evaluated by immunohistochemistry, using endoscopic biopsy specimens from 20 patients with AGMLs and 20 controls. Results: The number of CD3- and CD8-positive IELs increased in AGML specimens when compared with controls, and this increase was accompanied by a concomitant increase in TIA-1-positive cells. The epithelial cell layers of AGML specimens contained more GrB-7-positive phenotypically activated cytotoxic T cells than those in controls. Apoptotic ssDNA-positive epithelial cells were detected more frequently in AGML specimens than in controls, a feature which was paralleled by an increase in GrB-7-positive IELs in the former group of specimens. Conclusions: The present study showed that activated cytotoxic IELs and apoptotic epithelial cells are increased in number in gastric mucosa affected with AGMLs. These results provide evidence that this condition could be categorized as apoptotic gastritis with activation of the innate immune response. [ABSTRACT FROM AUTHOR]

Reports that transient increases in intracellular calcium (Ca2+), during the locomotion of fish epithelial keratocytes, occur more frequently in cells that become temporarily `stuck' to the substratum or when subjected to mechanical stretching. Influx of extracellular calcium; Increase in Ca2+ being involved in detachment of the rear cell margin; Finding of a mechanism by which cells can detect and transduce mechanical forces into biochemical signals that can modulate locomotion.

Proposes that extension of the front and retraction of the rear of fish epidermal keratocytes occurs perpendicularly to the cell edge, and that a graded distribution of extension and retraction rates along the cell margin maintains cell shape and size during locomotion. Graded radial extension (GRE) model; An idealized shape of a motile keratocyte moving according to the GRE model; Curvature of photoactivated actin lines; Further details.

We examined the relationship between proliferative activity determined by DNA polymerase α and clinicopathologic variables in breast cancer patients, and evaluated the usefulness of DNA polymerase α as a prognostic predictor in 337 early breast cancers with tumors smaller than 2 cm, which had favorable outcomes. About 60% of tumors had lower proliferative activity. A significant correlation was found between DNA polymerase α and ER, PgR, histological type, or the degree of infiltration into lymphatic vessels which reflect the prognosis. Cancers with higher DNA polymerase α activity were associated with shorter disease-free and overall survival times. In a multivariate analysis the DNA polymerase α was found to be an independent and significant factor in early breast cancer. [ABSTRACT FROM AUTHOR]

A new method of evaluating the degree of stenosis using the pressure loss coefficient is presented here. The pressure loss coefficient was obtained in patients with pulmonary or aortic stenosis by measuring the pressure and velocity of the blood simultaneously with a multisensor catheter. Although the pressure gradient across the stenosis was augmented by increasing the blood velocity with pharmacological loading, the pressure loss coefficient remained nearly constant. This confirmed that the pressure loss coefficient is more appropriate for evaluating the degree of stenosis than the pressure gradient, which depends on the blood velocity. The pressure loss coefficients obtained from the preoperative and postoperative catheterization data were compared to evaluate the effects of the surgical operation. A pressure loss coefficient of 15 was proposed as the critical value for the indication of operation. [ABSTRACT FROM AUTHOR]

Phenotypic and functional analysis was performed with lamina propria mononuclear cells (LPMCs) isolated from colonoscopic biopsies in 27 patients with ulcerative colitis (UC). The proportion of T lymphocytes displaying HLA-DR antigens, interleukin 2 (IL-2) receptor, and transferrin receptor was greater in active UC than in control diseases. When LPMCs were cultured with IL-2 or phytohemagglutinin for 72 h, there were no significant differences in the proportion of cells bearing these activation markers between active UC and controls. The proportion of CD56+ cells and lymphokine-activated killer (LAK) cell activity was lower in LPMCs from active UC than in control cells, and depletion of CD56+ cells from control lamina propria cells essentially eliminated LAK cell activity. Mucosal T lymphocytes may be activated in vivo during active inflammation in UC, and lower levels of intestinal LAK cell activity may be related to the decrease of CD56+ cells under these conditions. [ABSTRACT FROM AUTHOR]