Carboxylic monolayer formation for observation of intracellular structures in HeLa cells with direct electron beam excitation-assisted fluorescence microscopy

Intracellular structures of HeLa cells are observed using a direct electron beam excitation-assisted fluorescence (D-EXA) microscope. In this microscope, a silicon nitride membrane is used as a culture plate, which typically has a low biocompatibility between the sample and the silicon nitride surface to prevent the HeLa cells from adhering strongly to the surface. In this work, the surface of silicon nitride is modified to allow strong cell attachment, which enables high-resolution observation of intracellular structures and an increased signal-to-noise ratio. In addition, the penetration depth of the electron beam is evaluated using Monte Carlo simulations. We can conclude from the results of the observations and simulations that the surface modification technique is promising for the observation of intracellular structures using the D-EXA microscope.OCIS codes: (170.0170) Medical optics and biotechnology, (170.0180) Microscopy     

Cytomegalovirus cholangitis and pancreatitis in an immunocompetent patient

Cholangitis and pancreatitis associated with cytomegalovirus (CMV) infection in an immunocompetent patient is reported. Endoscopic retrograde cholangiography performed on a 55-year-old man for evaluation of the cause of jaundice and liver dysfunction revealed a distal focal irregular narrowing of the common bile duct. Microscopic findings of the resected specimen showed chronic cholangitis and CMV pancreatitis. Immunohistochemistry disclosed that epithelial cells in the inflamed bile duct were positive for CMV antigen, which was compatible with CMV cholangitis. Inflammation of the biliary tract or pancreas by CMV has been commonly reported as a complication in immunocompromised patients. Our report appears to be a rare case, but suggests that CMV cholangitis or pancreatitis should be considered in the differential diagnoses of common bile duct stenosis or pancreatitis even in immunocompetent individuals.     

Monocyte/Macrophage-Specific Marker CD163+ Histiocytic Sarcoma: Case Report with Clinical, Morphologic, Immunohistochemical, and Molecular Genetic Studies

We report a case of a very rare disorder, histiocytic sarcoma, from a review of our autopsy cases. The neoplastic cells that proliferated in organs throughout the body were large cells containing eosinophilic cytoplasm and pleomorphic nuclei with prominent nucleoli. In the bone marrow, erythrophagocytosis by neoplastic cells was observed. The neoplastic cells were positive not only for lysozymes and CD68 (KP-1, PG-M1, and Ki-M1P) but also for a monocyte/macrophage-specific marker, CD163. In contrast, the results of tests for markers of myeloid cells, lymphoid cells, and epithelial cells were all negative. In a polymerase chain reaction study of paraffin-embedded tissues, analyses for the rearrangement of immunoglobulin heavy chain and T-cell receptor-γ genes were negative. The current World Health Organization diagnostic criteria for histiocytic sarcoma regard immunohistochemical investigation as crucial. In this regard, the highly specific positivity for CD163 in this patient indicates that immunohistochemical staining of CD163 is very useful for the diagnosis of histiocytic sarcoma.     

Isolated ACTH deficiency with Graves' disease: a case report

A 60-year-old man was hospitalized with complaints of general malaise and weight loss. On admission, ACTH and cortisol levels were low, and thyroid function tests revealed hyperthyroidism. These findings and further examination led to a diagnosis of isolated ACTH deficiency (IAD) with Graves' disease. It is known that IAD is frequently associated with thyroid disease, but its association with Graves' disease is rare. The present case is worth noting, because some reports indicate that aggravation of associated Graves' disease may concomitantly aggravate adrenal insufficiency in patients with IAD.     

Endoscopic submucosal dissection of squamous cell carcinoma in the upper stomach 5 years after chemoradiotherapy for adenocarcinoma

Primary squamous cell carcinoma is rarely observed, with a reported incidence of 0.04–0.07 % of all gastric cancers. An 81-year-old male underwent chemoradiotherapy for type 1 gastric cancer of the posterior wall of the cardiac region in 2005. The tumor disappeared after 1 year of therapy, following which an area of white epithelium, approximately 30 mm in diameter and continuous with the esophageal mucosa, became visible. Biopsy of the white epithelium indicated normal squamous epithelium. An elevated lesion was subsequently detected in the area of white epithelium on upper gastrointestinal endoscopy during a follow-up examination 5 years after therapy. As a biopsy of the same site indicated squamous cell carcinoma, we performed endoscopic submucosal dissection. Histopathological examination indicated high-grade fibrosis due to radiotherapy and showed a moderately differentiated squamous cell carcinoma invading the scarred portion. We describe a case where the developmental process of a squamous cell carcinoma was observed using endoscopy, including narrow band imaging with magnification. This carcinoma likely originated from squamous metaplasia that developed after chemoradiotherapy was administered for a gastric cancer.