Atrial Arrhythmias and Atrial Involvement in Cardiac Sarcoidosis.

Severe ventricular arrhythmias such as high-grade atrioventricular block and ventricular tachycardia may cause lethal conditions or sudden death in patients with cardiac sarcoidosis (CS). Physicians should examine patients carefully for these conditions and treat them appropriately. As arrhythmias are being better diagnosed and treated, physicians are increasingly aware of atrial arrhythmias, which have not been focused upon as CS-related conditions, in patients with CS. This article reports a case of atrial flutter in sarcoidosis, and discusses literature findings on atrial arrhythmias and atrial involvement of CS. It is highly likely that atrial arrhythmia and supraventricular conduction disorder associated with or caused by CS are more common than previously thought. Physicians should pay careful attention for these conditions in the diagnosis and treatment of CS.

[A Case of Penile Squamous Cell Carcinoma, Sarcomatoid Subtype].

A 70-year-old man was referred to our department for further examination and treatment of a painless penile mass of about 2cm. The patient first noticed the mass onlya few weeks before presentation. Diagnostic biopsy was interpreted as leiomyosarcoma. Through systemic examinations the clinical stage of his disease was diagnosed as cT2N0M0 and we performed total penectomy. Histopathological examination for the totallyresected tissue disclosed the concomitant presence of regions compatible to squamous cell carcinoma and the results of immunohistochemistrywere compatible with the diagnosis of squamous cell carcinoma, sarcomatoid subtype of the penis. One month after the surgery, multiple metastases to left inguinal lymph nodes and lungs developed, for which systemic chemotherapy by doxorubicin was ineffective and the patient died of respiratoryinsufficiencyfive months after presentation.

The long elusive IgM Fc receptor, FcµR.

IgM exists as both a monomer on the surface of B cells and a pentamer secreted by plasma cells. Both pre-immune "natural" and antigen-induced "immune" IgM antibodies are important for protective immunity and for immune regulation of autoimmune processes by recognizing pathogens and self-antigens. Effector proteins interacting with the Fc portion of IgM, such as complement and complement receptors, have thus far been proposed but fail to fully account for the IgM-mediated protection and regulation. A major reason for this deficit in our understanding of IgM function seems to be lack of data on a long elusive Fc receptor for IgM (FcµR). We have recently identified a bona fide FcµR in both humans and mice. In this article we briefly review what we have learned so far about FcµR.

Exposure to High Doses of Lipopolysaccharide during Ovalbumin Sensitization Prevents the Development of Allergic Th2 Responses to a Dietary Antigen.

Food allergies are driven by aberrant T helper (Th) 2 cells. Lipopolysaccharide (LPS) influences the development of Th2-mediated diseases, but its role in food allergy and tolerance remains unclear. To address this issue, we established mouse models presenting allergic or tolerant responses to ovalbumin (OVA). Mice sensitized with crude OVA developed Th2 responses including acute diarrhea, increases in serum OVA-specific IgE, dominant production of serum OVA-specific IgG1, increases in Th2-type cytokines and proliferation of mast cells in duodenal and colonic tissues. Sensitization of mice with crude OVA and LPS abrogated Th2-type responses observed in allergic mice. The level of OVA-specific proliferation in mesenteric lymph node CD4(+) T cells was comparable in allergic and tolerant mice, indicating that the tolerance is not caused by anergy and apoptosis of antigen-primed T cells. Expression of Th1- and Th2-type cytokines was suppressed in whole spleen cells and/or purified spleen CD4(+) T cells of tolerant mice, indicating that the tolerance was not caused by the shift from Th2 to Th1. On the other hand, interleukin (IL)-10, a regulatory cytokine produced by regulatory T cells, was upregulated in whole spleen cells and purified spleen CD4(+) T cells of tolerant mice. Furthermore, spleen CD4(+) T cells from tolerant mice suppressed the growth of CD4(+) T cells from DO11.10 mice in co-culture. These results indicate that tolerance is induced in allergic mice by simultaneous exposure to LPS during sensitization with OVA and that a population of T cells producing IL-10 plays an important role in the tolerance induction.

Pathological and molecular biological approaches to early mesothelioma.

Malignant mesothelioma is an asbestos-related malignancy that arises primarily from mesothelial cells on the serosal surfaces of the pleural, peritoneal, and pericardial cavities. Malignant pleural mesothelioma (MPM) is most common, and its incidence is dramatically increasing worldwide as a result of widespread use of asbestos. Morphological discrimination between MPM and reactive mesothelial hyperplasia is difficult, and the most reliable pathological criterion for malignancy is mesothelial proliferation invading deeply into subpleural adipose tissues. To establish radical cure of MPM, it is crucial to find early-stage MPM of epithelial type, in which mesothelial proliferation is localized on the serosal surface of parietal pleura or limited within the submesothelial fibrous tissues of parietal pleura. The initial clinical presentation for patients with MPM is frequently dyspnea and/or chest pain due to large pleural effusion, and cytological analysis of pleural effusions is valuable to find patients with early-stage MPM of epithelial type. Recently, cytological features of MPM in pleural effusion, molecular markers for MPM, and genetic alternations of MPM have been reported. In this review, we discuss major issues on pathological and molecular biological approaches for diagnosis of early-stage MPM of epithelial type.

Practical approaches to diagnose and treat for T0 malignant pleural mesothelioma: a proposal for diagnostic total parietal pleurectomy.

Malignant pleural mesothelioma (MPM) remains suffering poor prognosis in spite of recent diagnostic and therapeutic progress. Although there is currently no established evidence, early diagnosis and early intervention may play a key role to improve prognosis of MPM, similarly to other malignancies. As pleural effusion is usually the first clinical sign of MPM, pleural effusion cytology is often the first diagnostic examination to be carried out. Since the sensitivity of pleural effusion cytology is approximately 60%, however, false-negative diagnosis is given to almost half of true MPM patients at this clinical step. One practical way to reduce the number of misdiagnosed MPM is to encourage performing thoracoscopic pleural biopsy unless definitive diagnosis other than MPM is established. There still remain a considerable number of patients with radiological/thoracoscopic T0 MPM who are misdiagnosed with nonspecific pleuritis after a complete investigation including thoracoscopic biopsies. Such patients will turn out to be malignant during follow-up period, although they have the best opportunity for long-term survival if only early therapeutic intervention is given. Currently, we are performing diagnostic total parietal pleurectomy in highly selected patients, who are characterized with strong clinical suspicion, positive pleural effusion cytology but uncertain pathological diagnosis, excellent cardiopulmonary reserve, and with written informed consent for highly invasive diagnostic surgery for pathologically unproven disease.

Establishment of a cell line from a Japanese patient useful for generating an in vivo model of malignant pleural mesothelioma.

Malignant pleural mesothelioma is a refractory tumor with increasing incidence. In the present study, we established six mesothelioma cell lines possessing two allele deletions of the p16(INK4A) gene and one allele deletion of the neurofibromatosis type 2 gene, MM16, MM21, MM26, MM35, MM46 and MM56, from pleural effusion fluids or surgically resected tumors of Japanese patients. MM21, MM26 and MM46 cells failed to develop tumors in BALB/c-nude mice following subcutaneous inoculation. MM16 and MM35 cells slowly generated tumors at the site of subcutaneous inoculation in BALB/c-nude mice, but lost the expression of mesothelioma-related markers such as calretinin, D2-40 and Wilms' tumor 1 in the subcutaneous tumors. On the other hand, MM56 cells rapidly generated tumors with the expression of calretinin and D2-40 in BALB/c-nude mice following subcutaneous inoculation. In addition, orthotopic implantation of MM56 cells into BALB/c-nude mice developed diffusely growing thoracic tumors by 3 weeks after implantation. Pleural effusions were observed in these mice 4 weeks after implantation. Thoracic tumors invaded aggressively into the chest wall 5 weeks after implantation and often metastasized into the lung, rib, peritoneum and pericardial cavity. On the pleural surface, MM56 cells were growing as single or multiple cell layers with the reactive mesothelium of recipient mice. These results indicate that MM56 cells can behave in a manner characteristic of human malignant pleural mesothelioma in the thoracic cavity of BALB/c-nude mice. The in vivo model using MM56 cells may be useful for studying the biological behavior of malignant pleural mesothelioma and developing its diagnostic and therapeutic strategies.

Development of Epidermoid Metaplasia of the Mucosa in Association with Esophageal Intramural Pseudodiverticulosis and Candidiasis.

We report a case of epidermoid metaplasia of the esophageal mucosa that developed in a patient with a long history of esophageal intramural pseudodiverticulosis (EIPD) complicated by candidiasis. The patient, a 69-year-old man, had been treated for about 3 years for EIPD with candidiasis. After candidiasis improved, the development of epidermoid metaplasia of the esophageal mucosa was observed. It comprised longitudinally arranged, multiple, small, whitish flecks with a scaly appearance on the mucosa of the middle to lower esophagus, and pathological examination demonstrated several fine keratohyalin granules in superficial layers of the squamous epithelium. Six months later, candidiasis was almost cured, but these small flecks had slightly increased in size, and pathological examination demonstrated epidermoid metaplasia consisting of a thick, acellular keratin layer and well-developed granular layer beneath it. We considered that chronic candida esophagitis played the principal pathogenetic role in the development of epidermoid metaplasia. EIPD may have provided an environment suitable for the growth of fungi, and mucinous material contaminated by Candida and excreted from the orifices of EIPD may have irritated the mucosa and induced epidermoid metaplasia.

Immunocytochemistry of CD146 is useful to discriminate between malignant pleural mesothelioma and reactive mesothelium.

Malignant pleural mesothelioma is a refractory tumor with poor prognosis associated with asbestos exposure. Pleural effusion is frequently observed in patients with malignant pleural mesothelioma, and cytological analysis is effective to detect malignant pleural mesothelioma. However, cytological discrimination between malignant pleural mesothelioma and reactive mesothelium is often difficult. Increased expression of CD146, a cell adhesion molecule, has been reported to be closely associated with an advanced stage of malignant melanoma, prostate cancer, and ovarian cancer. In this study, to evaluate the diagnostic utility of CD146 for discrimination between malignant pleural mesothelioma and reactive mesothelium, we examined immunocytochemical expression of CD146 in malignant pleural mesothelioma and reactive mesothelium using two clones of CD146 antibody, OJ79 and EPR3208, on smear specimens of effusion fluids. Immunocytochemical stains were semiquantitatively scored on the basis of immunostaining intensity (0, negative; 1, weak positive; 2, moderate positive; and 3, strong positive). CD146 expression was detected in 15 of 16 malignant pleural mesothelioma with median immunostaining score of 3 by OJ79, and in 19 of 21 malignant pleural mesothelioma with median immunostaining score of 2 by EPR3208. Strong immunoreactivity of CD146 was observed at the apposing surfaces of cell-cell interactions on the plasma membrane of mesothelioma cells. In addition, one OJ79-negative case of malignant pleural mesothelioma was positive for CD146 by EPR3208 and two EPR3208-negative cases of malignant pleural mesothelioma were CD146 positive by OJ79, showing that all 23 malignant pleural mesothelioma cases were positive for CD146 by either OJ79 or EPR3208. On the other hand, CD146 expression was undetectable in all reactive mesothelium cases by OJ79 and EPR3208. The sensitivity of OJ79 and EPR3208 was 94 and 90%, respectively, and the specificity was 100% for both clones. We propose that CD146 is a sensitive and specific immunocytochemical marker enabling differential diagnosis of malignant pleural mesothelioma from reactive mesothelium.

PIR-B-deficient mice are susceptible to Salmonella infection.

Paired Ig-like receptors of activating (PIR-A) and inhibitory (PIR-B) isoforms are expressed by many hematopoietic cells, including B lymphocytes and myeloid cells. To determine the functional roles of PIR-A and PIR-B in primary bacterial infection, PIR-B-deficient (PIR-B(-/-)) and wild-type (WT) control mice were injected i.v. with an attenuated strain of Salmonella enterica Typhimurium (WB335). PIR-B(-/-) mice were found to be more susceptible to Salmonella infection than WT mice, as evidenced by high mortality rate, high bacterial loads in the liver and spleen, and a failure to clear bacteria from the circulation. Although blood levels of major cytokines and Salmonella-specific Abs were mostly comparable in the two groups of mice, distinct patterns of inflammatory lesions were found in their livers at 7-14 days postinfection: diffuse spreading along the sinusoids in PIR-B(-/-) mice vs nodular restricted localization in WT mice. PIR-B(-/-) mice have more inflammatory cells in the liver but fewer B cells and CD8(+) T cells in the spleen than WT mice at 14 days postinfection. PIR-B(-/-) bone marrow-derived macrophages (BMMphi) failed to control intracellular replication of Salmonella in vitro, in part due to inefficient phagosomal oxidant production, when compared with WT BMMphi. PIR-B(-/-) BMMphi also produced more nitrite and TNF-alpha upon exposure to Salmonella than WT BMMphi did. These findings suggest that the disruption of PIR-A and PIR-B balance affects their regulatory roles in host defense to bacterial infection.

Clinical Features and Histopathology of Cardiac Sarcoidosis with Refractory Heart Failure: An Autopsy Case.

Treatment involving the insertion of an implantable cardioverter defibrillator and cardiac resynchronization therapy devices has markedly improved the prognosis of cardiac sarcoidosis. However, the prognosis remains poor in patients with advanced cardiac dysfunction or heart failure. We herein report the clinical course and histopathological findings of the autopsied heart of a patient with cardiac sarcoidosis with long-term refractory heart failure.

Perivascular epithelioid cell tumor of the rib.

We present a rare case of perivascular epithelioid cell tumor (PEComa) in the right 6th rib of a 28-year-old man. A plain computed tomography scan showed a round osteolytic lesion in the right 6th rib. The resected tissue contained a globular-shaped, soft tumor. Histologically, the tumor was rich in vasculature and exclusively composed of perivascular epithelioid cells with clear cytoplasm. Immunohistochemically, the tumor expressed diffusely a melanocyte marker, human melanoma black-45, and focally a myogenic marker, alpha-smooth muscle actin, but not an epithelial marker, AE1/AE3. Fontana-Masson-positive melanin pigments were present and c-kit receptor tyrosine kinase (CD117), involved in the development of melanocytes but not myogenic cells, was expressed in tumor cells. These findings indicate that the tumor is PEComa with some differentiation into melanocytes. Notably, owing to the unique location of the occurrence, the tumor occupied bone marrow tissues of the rib, resulting that the tumor has the potential for hematogenous metastasis. In spite of the lack of cells with severe atypia, necrosis, and numerous mitoses, tumor cells invaded into surrounding tissues and overexpressed cyclin D1. To the best of our knowledge, this is the first case report of PEComa arising from the rib with the signs of malignant potential.

Trametinib plus 4-Methylumbelliferone Exhibits Antitumor Effects by ERK Blockade and CD44 Downregulation and Affects PD-1 and PD-L1 in Malignant Pleural Mesothelioma.

INTRODUCTION: Malignant pleural mesothelioma (MPM) is a highly aggressive malignancy in which the mitogen-activated protein kinase pathway plays a critical role in the regulation of tumorigenesis. Hyaluronic acid (HA) is a major component of the extracellular matrix, and elevated HA levels with a concurrent increase in malignant properties are associated with MPM. METHODS: We evaluated the effects of trametinib, a mitogen-activated protein kinase (MEK) inhibitor, and 4-methylumbelliferone (4-MU), an HA synthesis inhibitor, alone and in combination on MPM cells in vitro and in vivo. We studied the effects of trametinib, 4-MU, and their combination on MPM cells by using cell viability assays, Western blot analysis, and a mouse xenograft model. RESULTS: Trametinib and 4-MU exhibited antiproliferative activity in MPM cells. Trametinib blocked MEK-dependent extracellular signal-regulated kinase (ERK) phosphorylation and decreased CD44 expression in a concentration-dependent manner. Trametinib inhibited the expression of Fra-1 (the activator protein 1 [AP1] component), inhibited ERK phosphorylation, and decreased CD44 expression. 4-MU inhibited ERK phosphorylation but not CD44 expression. In a mouse xenograft model, trametinib and 4-MU alone suppressed tumor growth compared with a control. The combination had a greater inhibitory effect than either monotherapy. Immunohistochemical analysis showed that trametinib treatment alone significantly reduced expression of programmed cell death 1 ligand 1. Furthermore, the combination of trametinib and 4-MU resulted in higher expression of programmed cell death 1 and programmed cell death 1 ligand 1 than did the 4-MU treatment alone. CONCLUSIONS: Our results suggest that trametinib and 4-MU are promising therapeutic agents in MPM and that further study of the combination is warranted.

Synergistic effect of fosfomycin and arbekacin on a methicillin-resistant Staphylococcus aureus-induced biofilm in a rat model.

Biofilms are a major concern for clinicians in the treatment of infectious disease because of the resistance to a wide range of antibiotics. Using a rat air pouch model, methicillin-resistant Staphylococcus aureus (MRSA) growing as a biofilm was treated with a combination of fosfomycin (FOM) and arbekacin (ABK) or by the agents alone. This model has the advantage of permitting frequent sampling of exudates for bacterial counts and anti-bacterial activity, and morphological examination of the biofilm structure and inflammatory process in the pouch tissues. A clear synergistic effect was observed in the rats treated with a combination of fosfomycin and arbekacin. Morphological studies using scanning electron microscopy and histological staining showed dramatic changes of the biofilm structure as well as the inflammatory response in the rats. These results suggested an enhancement of bactericidal activity of arbekacin penetrating through the biofilm layer by virtue of fosfomycin. A possible mechanism of the synergistic effect is discussed.

Modulatory effect of fosfomycin on acute inflammation in the rat air pouch model.

We examined the effect of fosfomycin (FOM) on the inflammatory response induced by carrageenan in the rat. Air pouches were induced subcutaneously on the backs of rats and injected with carrageenan. The rats were treated with either vehicle or FOM at a dose of 100 mg/kg 1 h before carrageenan challenge. After carrageenan challenge (48 h), the air pouches were removed and analyzed. The volume, protein amounts and cell counts in the exudate obtained from FOM-treated animals were significantly reduced compared with that from vehicle-treated animals. The contents of PGE(2) and TNF-alpha, and mRNA for cyclooxygenase-2 were also markedly suppressed in FOM-treated rats. Histological examination showed suppression of the inflammatory response in the pouch tissues from FOM-treated rats.

Inhibitory effect of quercetin on carrageenan-induced inflammation in rats.

We examined the effect of quercetin on the inflammatory response induced by carrageenan in the rat. Air pouches were induced subcutaneously on the backs of rats and injected with carrageenan. The rats were treated with either vehicle or quercetin at a dose of 10 mg/kg one hour before carrageenan challenge. Fourty-eight hour after carrageenan challenge, the air pouches were removed and analyzed. The volume, protein amounts and cell counts in the exudation obtained from the quercetin-treated animals were significantly reduced compared to those from vehicle-treated animals. The contents of PGE(2), TNF-alpha, RANTES, MIP-2 and the mRNA for cyclooxygenase-2 were also suppressed in these rats. The histological examination displayed the suppression of the inflammatory response in the pouch tissues from quercetin-treated rats. As the anti-inflammatory effect of the flavonols was more or less at the similar level among the quercetin-, isoquercitrin- or rutin-treated rats, it appeared that the sugar parts did not influence on the anti-inflammatory effect. Our study indicated that the flavonols modulated the inflammatory response, at least in part, by modulating the prostanoid synthesis as well as cytokine production.

Deterioration of vascular dementia caused by recurrent multiple small emboli from thoracic aortic atheroma.

We report a case of a 77-year-old man with deteriorating dementia caused by repeated multiple small cerebral embolisms from a thoracic aortic atheroma. Multiple small embolisms were confirmed by diffusion-weighted magnetic resonance imaging (DWI). The patient ultimately died due to aortic dissection. Pathological examinations revealed that no causative embolic source for multiple embolisms could be detected other than severe atheromatous ulcer in thoracic aorta. This case demonstrates that severe aortic atheroma has the potential to precipitate deterioration of vascular dementia.

Granulocyte-colony stimulating factor-producing gallbladder carcinoma.

Abstract A 78-year-old man was admitted to our hospital with right upper abdominal pain and fever. His general condition was poor. The laboratory data showed severe inflammatory reactions. Computed tomography revealed an irregular tumor in the gallbladder. (18)F-fluorodeoxy-glucose positron emission tomography (FDG-PET) showed high uptake by the tumor, with diffuse uptake in the spine. Based on the elevated leukocyte count and FDG-PET findings, a granulocyte-colony stimulating factor (G-CSF)-producing tumor was diagnosed (G-CSF 120 pg/mL). We performed cholecystectomy with central bisegmentectomy of the liver, lymph node dissection and right hemicolectomy. Histologically, the tumor was an adenosquamous cell carcinoma of the gallbladder. Immunohistochemical staining of the tumor cells was positive for G-CSF. Postoperatively, the general condition of the patient was improved. The fever subsided, the leukocyte count and serum G-CSF level normalized, and FDG-PET showed no uptake in the spine postoperatively. The patient showed no signs of recurrence at 27 months after undergoing surgery. FDG-PET is a useful method for diagnosing G-CSF-producing gallbladder carcinoma. Aggressive curative resection for G-CSF-producing gallbladder carcinoma may improve patients' general condition and prognosis.

Alveolar adenoma of the lung: a case report.

Alveolar adenoma is a rare pulmonary neoplasm. This report describes a case of alveolar adenoma of the lung in a 61-year-old woman. A chest X-ray demonstrated a solitary round pulmonary nodule. After six years of observation, this lesion had increased in size. Thoracoscopic left upper segmentectomy was performed on account of a possible low-grade malignant tumor. Histologically, the neoplastic epithelial cells, which had the appearance of proliferative type II pneumocytes, revealed no evidence of malignancy. These findings indicated that the tumor is alveolar adenoma of the lung. The course of disease remains uneventful, one year after the resection.

Adenocarcinomas associated with perianal fistulae in Crohn's disease have a rectal, not an anal, immunophenotype.

AIMS: Perianal fistulae are often observed in patients with Crohn's disease (CD), although the development of associated adenocarcinomas is very rare. The origin of adenocarcinomas in perianal fistulae associated with CD remains controversial and includes adjacent anal glands or rectal mucosa. Here, we attempted to determine the origin. METHODS: We performed immunohistochemical analysis on seven cases of adenocarcinomas in perianal fistulae associated with CD using antibodies against mucins (MUCs), cytokeratins (CKs) and the intestine-specific transcription factor CDX2. RESULTS: MUC2 and CK20 were expressed in all seven adenocarcinomas examined. MUC5AC/CLH2, MUC5AC/HGM and CDX2 were positive in four (57%), five (71%), and five (71%) adenocarcinomas, respectively. These proteins were positive in rectal mucosa, and negative in the anal glands. Six of seven adenocarcinomas (86%) were negative for CK7. CK7 was expressed in the anal glands, but not in rectal mucosa. CONCLUSIONS: Adenocarcinomas in perianal fistulae associated with CD showed immunohistochemical phenotypes similar to those of rectal-type mucosa, rather than the anal glands. The adenocarcinomas might originate from cells migrating from the adjacent rectal mucosa to the CD-associated perianal fistulae.