Heparin-binding epidermal growth factor-like growth factor (HB-EGF) is a critical growth factor for a number of physiological and pathological processes, such as wound healing, atherosclerosis and cancer proliferation. HB-EGF is synthesized as a membrane form (proHB-EGF), and is shedded at the cell surface to yield soluble HB-EGF, resulting in making it active. In this study, the involvement of reactive oxygen species (ROS) in stimuli-induced shedding of HB-EGF was investigated using monkey kidney Vero cells overexpressing HB-EGF (Vero-H cells). 12-O-tetradecanoylphorbol-13-acetate (TPA), lysophosphatidic acid (LPA) as a ligand for seventransmembrane G protein coupled receptors (GPCR) and sorbitol as stress induced shedding of HB-EGF mediated protein kinase C (PKC)-δ, mitogen-activated protein kinase (MAPK) and p38MAPK, respectively. These stimuli-induced sheddings of HB-EGF were inhibited by N-acetyl-L-cysteine (NAC), suggesting the involvement of ROS. As specific inhibitors of these protein kinases inhibited the shedding of HB-EGF, these signaling pathways seem to be independent, respectively. In contrast, γ-ray irradiation did not induce shedding although it did increase intracellular ROS levels. Taken together, these results suggest that the synergistic generation of ROS and the activation of protein kinase are required to promote stimuli-induced shedding of HB-EGF.

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Lipoblasts are conceptually a precursor or immature form of adipocytes and histologically defined as lipid-containing, mono－ or multivacuolated cells possessing hyperchromatic, indented or often scalloped nuclei. They are essentially identified in neoplastic conditions and assumed to recapitulate, to some extent, the differentiation process of normal fat (adipogenesis) like their potential normal counterpart, preadipocyte or preadipose cell. Traditionally, great emphasis has been placed on the identification of lipoblasts in diagnostic pathology, particularly of liposarcoma. However, it is not always an easy task for pathologists because of a variety of histological mimics such as Lochkern cells, brown fat cells and pseudolipoblasts. Currently, lipoblasts are not a prerequisite for the diagnosis of liposarcoma partly because of some benign tumors harboring lipoblasts or lipoblast-like cells such as spindle cell/pleomorphic lipoma and chondroid lipoma, although their presence is still crucial for proper diagnosis. This review summarizes the clinicopathologic features of lipoblasts, their histological mimics and representative benign tumors carrying lipoblasts to facilitate routine pathology practice and to avoid erroneous diagnosis of liposarcoma.

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A 74-year-old man was hospitalized due to hematemesis. Upper gastrointestinal endoscopy revealed a very large and dark red mass in the cardiac region of the stomach that extended from the upper esophagus. A biopsy specimen showed hemorrhagic tissue and no malignant cells. The tumor-like region ulcerated at 5 days after the administration of intravenous lansoprazole at a dose of 30 mg twice a day and resolved with scar formation at 2 months after a change to oral rabeprazole at a dose of 10 mg/day.We diagnosed the patient with gastroesophageal submucosal hematoma. Gastroesophageal submucosal hematoma is a rare complication. In this case, we could follow the process of its disappearance by endoscopy.

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Recently, some reports have indicated that limbic encephalitis associated with anti-voltage-gated potassium channel complex antibodies (VGKC-Ab) is a cause of adult-onset mesial temporal lobe epilepsy (MTLE). We report a 53-year-old woman who had her first epileptic seizure at the age of 50 years old. Examination by 3-Tesla brain MRI revealed left hippocampal high signal intensity and swelling on fluid-attenuated inversion recovery (FLAIR) and T2-weighted imaging at 2 months after her first seizure. The patient received intravenous methylprednisolone and carbamazepine 300 mg/day. One month later, MRI revealed improvement of her left hippocampal abnormalities. Thereafter, she had no seizures, however, three years after her first seizure, EEG revealed a seizure pattern in the left temporal region. Brain MRI revealed left hippocampal high signal intensity and brain fluorodeoxyglucose positron emission tomography revealed hypermetabolism. Her serum VGKC-Ab levels were 118 pM(normal < 100 pM). Intravenous methylprednisolone therapy was reinitiated. Two months later, her hippocampal abnormalities had improved and 3 months later her VGKC-Ab levels decreased to 4.4 pM. Remission of the epileptic seizures was also observed. This MTLE in the middle age was considered as limbic encephalitis associated with anti- VGKC-Ab. In cases of unexplained adult-onset MTLE, limbic encephalitis associated with anti-VGKC-Ab, which responds well to immunotherapy, should be considered in the differential diagnosis.

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Electric warm-water lavage toilet seats are in wide use as an appliance beneficial for the maintenance of hygiene and the prophylaxis and improvement of conditions such as constipation and hemorrhoids. In this study, we surveyed the bacterial content in the lavage water of warm-water lavage toilet seats, and fecal bacterial contamination of the gluteal and genital regions due to droplet infection from post-defecation lavage, to examine the problems inherent to the use of such lavage units. The presence of viable bacteria in lavage water was confirmed in this survey. Viable bacterial counts in lavage water were 3-times higher in household units compared to units in public facilities, suggesting a correlation with the replenishment of lavage tank water with fresh water containing residual free chlorine.

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Rheumatoid arthritis (RA) is an autoimmune disease represented by chronic inflammation and following structural damage at the articular joints. Progression of the disease causes disability and subsequent early retirement or a care-requiring condition. Although new agents have the potential of complete inhibition of joint damage, there is still a considerable number of patients with progressed joint damage who couldn’t receive the benefits of these agents because of the long duration of their disease or uncontrollable disease activity. Thus, a new treatment tool for RA aiming at joint repair is necessary. Mesenchymal stem cells (MSCs) are known to build bone and cartilage, and also have immunosuppressive ability. We have considered MSCs as a new treatment tool of RA, and have reported that MSCs suppress osteoclastogenesis. More recently, we also reported that inflammation induces osteogenesis and suppresses the chondrogenesis of MSCs. An investigation of a new delivery system of MSCs to the target lesion is now ongoing. The data from this investigation suggest that MSCs can be a new application in the treatment of RA.

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Two cases of acute respiratory distress syndrome related to zinc fume inhalation and zinc powder inhalation are presented. Case 1 demonstrated acute respiratory symptoms during the work of distortion correction of iron boards, coated with a rust preventative including rich zinc using an acetylene gas burner. Case 2 occurred after the work of applying a rust preventative that included zinc powder, mainly using an airless compressor. Since both were working in a boathouse, without using protective equipment, the possible causes of Case 1 and 2 were inhalation exposure to zinc fumes and zinc powder, respectively. The two patients showed similar clinical courses, including favorable treatment outcomes, mimicking acute respiratory failure complicated by a metal fume fever.

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A quick method to measure the number and the concentration of airborne bacteria was examined by combining bacteria staining with a crystal violet solution and absorptiometry. The suspension of the bacteria isolated from the environment was adjusted to 3.0 × 10⁸ colony forming units (CFU) / ml in E. coli equivalent, and a 10-fold dilution series was created. After centrifugation of each bacterial suspension, the supernatant was removed and the bacteria were stained by adding a crystal violet solution. The sample was centrifuged again, and the supernatant was collected and named the unabsorbed sample. The residual bacteria were washed two times, and ethanol was added to the stained cells. The recovered solution collected by centrifugation of the cells was named the recovered sample.The chemicals in the samples were examined by high performance liquid chromatography, but no peak could be observed without the staining material. Absorption spectrophotometry showed that the determination limit of bacteria in the unabsorbed samples was 3.0 × 10⁷ CFU / ml in E. coli equivalent and that in the recovered samples was 3.0 × 10⁸ CFU / ml, indicating that the unabsorbed sample had a lower determination limit.

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