Disinfection and monitoring of Mycobacterium avium complex in the environment: A novel approach to the management of hot tub lung.

A 45-year-old man visited our hospital with a chronic cough and breathing difficulties. Chest computed tomography revealed diffuse granular shadows. Mycobacterium avium (M. avium) was cultured from bronchoalveolar lavage fluid (BALF). Surgical lung biopsy revealed non-necrotizing granulomas, and M. avium-specific PCR was positive in the tissue. M. avium was also cultured in a sample from the inlet of the patient's bathtub. Mycobacterium avium tandem repeat variable-number tandem-repeat loci (MATR-VNTR) analysis confirmed that the M. avium cultured from BALF and the bathtub inlet had identical allele profiles. The patient's symptoms and oxygenation improved while the patient was in hospital, presumably because of lack of ongoing exposure to M. avium. He was diagnosed with hot tub lung. We advised the patient to avoid bathing to avoid re-exposure. However, the patient was unwilling to follow this advice. Therefore, his bathtub and pipework were disinfected by heating them to over 70 °C. We confirmed that the disinfection has been successful by repeated culture of environmental samples. Three months after resuming bathtub use, the patient's symptoms resolved, and the pulmonary shadows seen on the initial radiography did not recur. For the treatment of hot tub lung, disinfection of M. avium complex in the environment should be considered and the environment should be monitored to confirm eradication.

Clinicopathologic differences of gastric neoplasms between Helicobacter pylori-infected and -naïve patients: a multicenter retrospective analysis.

BACKGROUND: The incidence of gastric neoplasms in Helicobacter pylori (Hp)-naïve patients has recently increased due to a remarkable decrease in the Hp-infected population in Japan. We investigated the clinicopathologic differences between Hp-infected gastric neoplasms (HpIGNs) and Hp-naïve gastric neoplasms (HpNGNs) that have not been fully elucidated so far. METHODS: This retrospective multicenter study investigated 966 consecutive patients with 1131 gastric dysplasia or cancers who underwent endoscopic or surgical treatment for the recent decade. Clinicopathologic features were compared between HpIGN and HpNGN cases. RESULTS: One thousand and sixty-eight HpIGNs in 916 patients included 877 differentiated types and 191 undifferentiated types. Sixty-three HpNGNs in 50 patients included 57 differentiated types (35 foveolar types, 15 intestinal types, 6 fundic-gland types, and 1 other differentiated type) and 6 undifferentiated types. HpNGNs occurred in younger (59.5 vs. 71.8 years, p < 0.05) and female patients (40.0% vs. 26.5%, p < 0.05), were found more frequently in the proximal compartment (p < 0.05), and had smaller size (median 4.0 vs. 20.0 mm, p < 0.05). Histologically, HpNGNs and HpIGNs both primarily consisted of differentiated type (90.5% vs. 82.1%, p = 0.089) and HpNGNs showed lower prevalence of invasive cancer (11.1% vs. 37.6%, p < 0.05) and lymphovascular invasion (1.6% vs. 31.6%, p < 0.05). Nearly all HpNGNs (62/63, 98.4%) were diagnosed in early pathological stage, while 16.1% (172/1068) of HpIGNs were diagnosed in advanced stage (p < 0.05). CONCLUSIONS: HpNGNs is recently on the increase but shows lower malignant nature regardless of histologic type than HpIGN. Endoscopic gastric cancer screening will be reviewed via cost effectiveness for Hp-naïve individuals in future.

Pure Red Cell Aplasia Induced by Atezolizumab in a Patient with Small-Cell Lung Cancer Successfully Treated with Steroid Therapy: A Case Report.

Introduction: Combination therapy of atezolizumab and chemotherapy has become the standard treatment for small-cell lung cancer. Immune-related adverse events (irAEs) can occur during immune checkpoint inhibitor administration. A few reports exist on pure red cell aplasia (PRCA) as an irAE after atezolizumab treatment. PRCA is characterized by normocytic-normochromic anemia, a marked decrease in reticulocytes, and a decrease in bone marrow erythroblasts. Here, we report a case of atezolizumab-induced PRCA. Case Presentation: A 69-year-old male patient was brought to the emergency department with the chief complaint of seizures. Multiple metastatic brain tumors and a mass suspected to be the primary lesion in the right hilar region were observed. After a brain biopsy, he was diagnosed with small-cell lung cancer (cT1cN0M1c stage IVB). He received four courses of carboplatin, etoposide, and atezolizumab in combination with whole-brain irradiation, which led to a partial response. After six courses of atezolizumab maintenance therapy, severe anemia (hemoglobin, 3.4 g/dL) was observed. PRCA induced by atezolizumab was diagnosed using a bone marrow biopsy performed during red blood cell transfusion. Treatment was started with prednisolone 25 mg/day (0.5 mg/kg/day). Anemia improved, and the dose was gradually reduced to 5 mg/day. Conclusion: Reports of PRCA as an irAE are rare but important; hence, we reported this case.

Intraductal Tubulopapillary Neoplasm Diagnosed Before Surgery: A Case Report.

Intraductal tubulopapillary neoplasm (ITPN) is a rare disease in the pancreas with a better prognosis than pancreatic ductal adenocarcinoma (PDAC) and a different treatment strategy. Therefore, it is important to confirm its diagnosis before the surgery. However, few cases have been diagnosed preoperatively. In this report, we present a case of ITPN that was successfully diagnosed preoperatively. A 70-year-old female patient was incidentally diagnosed with a pancreatic tumor. The patient was asymptomatic, and her blood tests were all within the normal range. A dynamic computed tomography scan showed an indistinct mass with small cysts and a dilated pancreatic duct. The mass was well contrasted in the arterial phase. These findings were not enough to confirm ITPN. Therefore, endoscopic ultrasonography fine needle aspiration biopsy was performed. The specimen had no mucin and the neoplastic cells exhibited a tubulopapillary growth pattern. Moreover, the neoplastic cells were immunohistochemically positive for MUC1, CK7, and CK20, but negative for MUC2, MUC5AC, synaptophysin, and Bcl-10. Consequently, the preoperative diagnosis was confirmed as ITPN. Hence, a subtotal-stomach-preserving pancreaticoduodenectomy was performed, and the patient had a good postoperative course and was discharged after 26 days. Tegafur, gimeracil, and oteracil were administered as postoperative adjuvant chemotherapies for one year. Seventeen months after the surgery, no recurrence has been detected. ITPN and PDAC have different prognoses and treatment strategies. In this report, we experienced a case of ITPN preoperatively diagnosed and successfully treated.

Comparison of Ultra-Magnifying Endocytoscopic and Hematoxylin-Eosin-Stained Images of Lung Specimens.

Endocytoscopy enables real-time observation of lesions at ultra-magnification. In the gastrointestinal and respiratory fields, endocytoscopic images are similar to hematoxylin-eosin-stained images. This study aimed to compare the nuclear features of pulmonary lesions in endocytoscopic and hematoxylin-eosin-stained images. We performed an endocytoscopy to observe resected specimens of normal lung tissue and lesions. Nuclear features were extracted using ImageJ. We analyzed five nuclear features: nuclear number per area, mean nucleus area, median circularity, coefficient of variation of roundness, and median Voronoi area. We conducted dimensionality reduction analyses for these features, followed by assessments of the inter-observer agreement among two pathologists and two pulmonologists to evaluate endocytoscopic videos. We analyzed the nuclear features of hematoxylin-eosin-stained and endocytoscopic images from 40 and 33 cases, respectively. Endocytoscopic and hematoxylin-eosin-stained images displayed a similar tendency for each feature, despite there being no correlation. Conversely, the dimensionality reduction analyses demonstrated similar distributions of normal lung and malignant clusters in both images, thus differentiating between the clusters. The diagnostic accuracy of the pathologists was 58.3% and 52.8% (κ-value 0.38, fair), and that of the pulmonologists was 50% and 47.2% (κ-value 0.33, fair). The five nuclear features of pulmonary lesions were similar in the endocytoscopic and hematoxylin-eosin-stained images.

Gray zone lymphoma effectively treated with cyclophosphamide, doxorubicin, vincristine, prednisolone, and rituximab chemotherapy: A case report.

BACKGROUND: B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and classical Hodgkin lymphoma (BCLu-DLBCL/cHL), also referred to as gray zone lymphoma (GZL), is known to share features with cHL and DLBCL. However, GZL is often difficult to diagnose. There is no consensus regarding the optimal therapeutic regimen. Most reported cases of GZL have been in Caucasian and Hispanic individuals, and its incidence is lower in African-American and Asian populations, including the Japanese population. CASE SUMMARY: A 69-year-old female presented at our hospital with a growing mass on the right side of her neck. An elastic, soft mass measuring 9 cm × 6 cm was palpable in the right cervical region. Laboratory analyses showed pancytopenia, increased serum lactate dehydrogenase levels, and markedly increased levels of soluble interleukin-2 receptor. Enhanced computed tomography (CT) and fluorodeoxyglucose positron emission tomography (PET)/CT revealed multiple lesions throughout her body. She was diagnosed with GZL based on the characteristic pathological findings, the immunophenotype [CD20+, PAX5+, OCT2+/BOB1 (focal+), CD30+, CD15-], and the strong positive expression of neoplastic programmed cell death protein ligand 1 (PD-L1) in her lymphoma cells. The lymphoma was stage IV according to the Lugano classification and high-risk according to the International Prognostic Index for aggressive non-Hodgkin lymphoma. The patient received cyclophosphamide, doxorubicin, vincristine, prednisolone, and rituximab (R-CHOP) chemotherapy because the tumor cells were CD20+. She has remained in complete remission for 3 years. CONCLUSION: GZL was diagnosed based on histopathology and immunophenotyping with ancillary PD-L1 positivity. R-CHOP chemotherapy was an effective treatment.

Intestinal-type gastric dysplasia in Helicobacter pylori-naïve patients.

Gastric dysplasia and gastric cancer in Helicobacter pylori (Hp)-naïve patients usually exhibit a gastric phenotype, reflecting gastric mucosa without intestinal metaplasia (IM). We showed that intestinal-type gastric dysplasia (IGD) rarely occurs in the Hp-naïve stomach. In the last 10 years, we treated 1760 gastric dysplasia and gastric cancer patients, with 3.6% (63/1760) being Hp-naïve. Among these, ten were diagnosed with 14 IGDs and enrolled in this retrospective analysis. All lesions were observed by white-light endoscopy (WLE) and narrow-band imaging with magnification endoscopy (NBIME). We analyzed their endoscopic and microscopic features and patient demographics. Five men and five women aged 64 ± 21 years were included. WLE showed the depressed lesions mimicking a benign raised erosion in the prepyloric compartment. Multiple growths were confirmed in 30% (3/10) of patients. NBIME showed a near-regular microstructure and capillaries in 50% (7/14) of lesions with a gastritis-like appearance. Histologically, background mucosa was non-atrophic pyloric gland tissue, but 40.0% of samples (4/10) contained sporadic IM. Most of the lesions (8/14) were low-grade dysplasia, and others had a high-grade component, with one progressing to intramucosal carcinoma. The neoplastic surface was widely covered with foveolar epithelium in 57.1% (8/14). Immunohistochemically, neoplastic cells expressed CDX2 in all patients (14/14), MUC2 and CD10 in 92.9% (13/14), MUC5AC in 14% (2/14), and no expression of MUC6, showing an intestinal phenotype. Ki-67 was overexpressed with a mean labeling index of 58.3 ± 38.5%, and p-53 was overexpressed in 92.9% (13/14), regardless of the dysplastic grade. The IGD rarely occurs in Hp-naïve patients with distinctive clinicopathologic characteristics.

Real-life long-term safety and effectiveness of omalizumab in Japanese pediatric patients with severe allergic asthma: A post-marketing surveillance.

BACKGROUND: Omalizumab is approved as add-on therapy for pediatric asthma since 2013 in Japan, however, its data in clinical practice is limited. This post-marketing surveillance aimed to evaluate long-term safety and effectiveness of omalizumab in Japanese pediatric patients with severe allergic asthma in real-life setting. METHODS: This 104-week, multicenter surveillance was conducted from September 2013 to May 2019 by central registration method. Patients with severe allergic asthma aged ≥6 and < 15 years at initiation of treatment who were first-time omalizumab users were included. The primary endpoints included incidence of adverse drug reactions and physician's Global Evaluation of Treatment Effectiveness (GETE). The secondary endpoints included incidence of serious adverse events, adverse events and adverse drug reactions of special interest and asthma exacerbation-related events. RESULTS: Of the 128 patients enrolled, 127 completed the surveillance and were included for safety and effectiveness analysis. Thirteen patients experienced 20 adverse drug reactions with an incidence rate of 10.2%. The most frequent adverse drug reactions were pyrexia (2.4%) and urticaria (1.6%). In total, adverse events and serious adverse events occurred in 60 (47.2%) and 30 patients (23.6%) respectively. Two patients experienced anaphylactic reaction and 1 patient experienced type 1 hypersensitivity. 77.2% had an effective response to omalizumab according to GETE at final assessment, and frequency of all asthma exacerbation-related events decreased in post-treatment versus pre-treatment. CONCLUSIONS: Long-term omalizumab treatment showed no new safety signals in pediatric patients with severe allergic asthma. The observed safety and effectiveness profile was consistent with previous studies.

Real-world Safety and Efficacy of Indacaterol Maleate in Patients with Chronic Obstructive Pulmonary Disease: Evidence from the Long-term Post-marketing Surveillance in Japan.

Objective Evidence concerning the safety and efficacy of indacaterol maleate in a real-life setting is limited. The objective of this post-marketing surveillance was to evaluate the real-life safety and efficacy of indacaterol maleate in Japanese patients with chronic obstructive pulmonary disease (COPD). Methods This was a 52-week post-marketing surveillance conducted between April 2012 and December 2018. The safety endpoints included the incidence of adverse events (AEs), serious adverse events (SAEs), and adverse drug reactions (ADRs). The efficacy endpoints included the physician-reported global evaluation of treatment effectiveness (GETE), change from baseline in the COPD assessment test (CAT) results, forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), and %FEV1 following 4, 12, 26, and 52 weeks of indacaterol administration. Results Of the 1,846 enrolled patients, 1,726 were included in the safety and efficacy analyses. The mean age of the patients was 72.5 years old. Cough, pneumonia and COPD worsening were the most common AEs reported, while pneumonia (1.04%) was the most common SAE, and cough (1.68%) was the most common ADR. GETE showed that 69.70% of patients achieved an excellent/good/moderate response following indacaterol treatment. The CAT score decreased, and lung function parameters (FVC, FEV1 and %FEV1) improved across all the COPD stages following treatment with indacaterol. Conclusion Indacaterol showed a favorable safety and tolerability profile in Japanese patients with COPD without new safety signals observed in real-life settings. These findings demonstrated that indacaterol is an effective maintenance treatment in real-life practice for Japanese patients with COPD.

A case of rheumatoid arthritis with multiple lung rheumatoid nodules successfully treated with tofacitinib.

Sporadic cases of rheumatoid nodules (RNs) in the lung during treatment with tumour necrosis factor (TNF) inhibitors have been reported, but no treatment has been established. Here, we report a case of symptomatic lung RNs refractory to abatacept (ABT) and intravenous cyclophosphamide (IVCY) that improved with tofacitinib (TOF) treatment. A 75-year-old Japanese woman with a 10-year history of rheumatoid arthritis (RA) presented with a cough and haemoptysis during treatment with etanercept (ETN). Radiographic examinations revealed multiple nodules that were diagnosed as lung RNs via biopsy. The ETN was discontinued and ABT followed by IVCY was introduced; however, neither was sufficiently effective against the lung RNs. Thereafter, TOF was started and the lung RNs improved rapidly. The precise mechanisms that induce RNs during treatment with TNF inhibitors are unknown. Cytokines (IL-23 and IL-6) are suspected to be involved. TOF may be a reasonable strategy for treating symptomatic lung RNs.

Real-life safety and efficacy of omalizumab in Japanese patients with severe allergic asthma who were subjected to dosing table revision or expansion: A post-marketing surveillance.

BACKGROUND: Omalizumab is an anti-immunoglobulin E monoclonal antibody approved for patients with severe allergic asthma in Japan. With regard to omalizumab dosage in Japanese adults with severe allergic asthma in clinical practice settings, this post-marketing surveillance evaluated safety and efficacy of the dosing table revision (DTR) based on a dosing regimen of omalizumab administration every 4 weeks dosing regimen and dosing table expansion (DTE) for patients with baseline IgE levels >700 IU/mL. METHODS: This 52-week, multicenter study, conducted from September 2013 to November 2018, evaluated omalizumab safety outcomes including adverse events (AEs), serious AEs (SAEs), adverse drug reactions (ADRs), efficacy outcomes including Global Evaluation of Treatment Effectiveness (GETE), change in oral corticosteroid dose, and asthma exacerbation-related events such as hospitalization, emergency room visits, and worsening of symptoms. RESULTS: Of the 405 patients registered in the study, safety was evaluated in 392 and efficacy in 390. The mean age of patients was 58.5 years and 58.7% were women. In total, 41.3% of the patients were subjected to DTE and 58.7% to DTR. In the safety dataset, 6.6% experienced an ADR, 32.9% experienced an AE, and 16.1% experienced an SAE. In the efficacy dataset, 63.3% of patients at Week 16 and 63.5% at Week 52 had an 'effective' or 'good' GETE score. Omalizumab was associated with a reduction in worsening of asthma symptoms requiring systemic corticosteroids and frequency of hospitalization. All outcomes were comparable among the DTE and DTR subgroups. CONCLUSION: The findings from this study support the safety and efficacy of omalizumab administered based on the revised and expanded dosing table in Japanese patients with severe allergic asthma.

Synchronously Multiple Gastric Adenocarcinomas with Intestinal Mucin Phenotype in a Patient not Infected with Helicobacter pylori, Showing a Gastritis-like Appearance.

Helicobacter pylori (H. pylori)-negative gastric cancer (HPNGC) usually shows a gastric mucin phenotype, but there are a few case reports of HPNGC with an intestinal mucin phenotype. We herein report a case of multiple HPNGC with an intestinal mucin phenotype showing a gastritis-like appearance. A 68-year-old H. pylori-uninfected man was suspected of having antral gastritis on endoscopy, but a histologic examination revealed multiple well-differentiated adenocarcinomas with positive-CDX2/MUC2/CD10 and negative-MUC5AC/MUC6. P53 was overexpressed, and intestinal metaplasia was sporadically detected in the non-atrophic mucosal background, thus indicating H. pylori-unrelated multistage carcinogenesis. The neoplastic surfaces were covered by a non-neoplastic epithelium, which caused a gastritis-like appearance. This report suggested the possibility of overlooking this neoplasm.

Two Cases of Eosinophilic Gastroenteritis With Rare Manifestations Revealed in Medical Checkup Findings.

Eosinophilic gastroenteritis (EGE) is characterized by dense infiltration of eosinophils in gastrointestinal tissues, resulting in morphological and functional abnormalities of the gastrointestinal tract. EGE susceptibility is most common among individuals aged 40-50 years old, and hence it is likely that affected patients will be encountered at the time of a medical checkup. In this report, we present two rare cases of EGE that presented interesting manifestations in findings obtained in a fluoroscopic examination performed at an annual medical checkup. Accumulation of case reports is important to provide information to pathologists to enable them to make correct early diagnosis and begin effective treatment at the earliest.

Measurement of Adenosine Deaminase in Ascitic Fluid Contributed to the Diagnosis in a Case of Tuberculous Peritonitis.

A diagnosis of tuberculous peritonitis (TBP) is difficult because of nonspecific manifestation and limited effectiveness of conventional diagnostic tools. Recently, the usability of measurement of ascitic adenosine deaminase (ADA) was shown. We report here a case of TBP in which measurement of ascitic ADA contributed to the diagnosis. A 93-year-old male developed a large amount of ascites. Analyses of the ascitic fluid revealed exudation, though antibiotics treatment was ineffective. Using paracentesis, the ADA level in the ascites was measured and shown to be high. Under suspicion of TBP, an exploratory laparoscopy was performed and a definitive diagnosis of TBP was made.

Real-world safety and efficacy of omalizumab in patients with severe allergic asthma: A long-term post-marketing study in Japan.

BACKGROUND: Omalizumab (anti-IgE monoclonal antibody) is an approved add-on therapy for Japanese patients with severe allergic asthma. As directed by the Ministry of Health, Labor and Welfare Japan, a post-marketing surveillance (PMS) study on omalizumab was conducted between 2009 and 2017. METHODS: The PMS observed safety and efficacy of omalizumab in patients treated with open-label omalizumab for 52 weeks (with optional 2-year extension period). Primary safety outcomes included incidence and severity of adverse events (AEs) and adverse drug reactions (ADRs). Primary efficacy outcomes included physician-assessed global evaluation of treatment effectiveness (GETE). Asthma-exacerbation-related events including requirement for additional systemic steroid therapy, hospitalization, emergency room visits, unscheduled doctor visits, and absenteeism were also evaluated. RESULTS: Of 3893 patients registered, 3620 (age [mean ±â€¯SD] 59.3 ±â€¯16.11 years) were evaluated for 52 weeks; 44.12% were aged ≥65 years and 64.45% were women. Overall, 32.24% reported AEs and 15.30% reported serious AEs. ADRs were seen in 292 (8.07%) patients. GETE results showed that the majority of patients experienced clinical improvements (58.29% at 16 weeks and 62.40% at 52 weeks). Nearly half of all patients (47.96%) were free from asthma exacerbations after therapy. Omalizumab also reduced all events related to asthma exacerbations. No specific ADRs were observed in the elderly population. CONCLUSIONS: This post-marketing study confirmed the clinically meaningful benefits of omalizumab in a majority of patients from Japan, and showed safety and efficacy in a real-life clinical setting to be consistent with previous reports.

An evaluation of the diagnostic and prognostic significance of p16(INK4a) /p21(WAF1/Cip1) immunostaining in squamous intraepithelial lesions of the uterine cervix using liquid-based cytology specimens.

Human papillomavirus (HPV) infection frequently causes squamous intraepithelial lesions (SIL) of the uterine cervix and consequently gives rise to squamous cell carcinoma. It is therefore important to identify cases that potentially develop higher grades of SIL at an early stage of the disease. In this study, we thus investigated whether immunocytochemistry for p21(WAF1/Cip1) and p16(INK4a) could be applicable in the diagnosis and the prognostic prediction of SIL in combination with genomic analyses of HPV. The genomic analysis of high-risk HPV (hrHPV), which was done by reversed dot blotting and by in situ hybridization, and immunocytochemistry were performed on liquid-based cytological specimens. A cross-sectional study comprising 145 cases of NILM, ASC-US, LSIL, and HSIL indicated that the incidence of the positive cases for p16(INK4a) and p21(WAF1/Cip1) and hrHPV increased with the grade of SIL. A double positive status for p16(INK4a) and p21(WAF1/Cip1) was a significant discriminator between HSIL and LSIL/NILM, even when applied in conjunction with the genomic test for hrHPV (P = 0.006 by logistic regression analysis). However, a prospective study employing 61 NILM/ASC-US cases, revealed that the p16(INK4a) /p21(WAF1/Cip1) immunostaining was not a significant predictor for the progression of SIL, whereas the cytological diagnosis (NILM vs. ASC-US) and the infection status of hrHPV conferred significant effects on the prognosis. Immunostaining of p16(INK4a) and p21(WAF1/Cip1) provides additional information on the cytological diagnosis of SIL. A further analysis using a larger population is warranted to obtain a conclusive result regarding the prognostic significance of p16(INK4a) /p21(WAF1/Cip1) immunocytochemistry in the diagnosis of SIL.

Re-evaluation of the histological criteria for complete hydatidiform mole: Comparison with the immunohistochemical diagnosis using p57KIP2 and CD34.

Differential diagnosis between complete and partial hydatidiform mole is clinically important because of the difference in the risk of developing more malignant form of the molar diseases. In this report, the classical microscopic criteria were re-evaluated in the light of the immunohistochemistry of p57KIP2 in the attempt to establish robust morphological criteria for the differential diagnosis. Thirty-six consecutive cases clinically suspected to be hydatidiform mole were employed. The histological criteria were scored by three pathologists. The cases were categorized into three entities of the molar diseases in accordance with the immunohistochemistry of p57KIP2 and CD34. The diagnostic significance of the histological criteria was evaluated in a logistic regression model. Of 36 cases, the immunohistochemistry revealed that 28 were complete and 6 were partial hydatidiform mole, while 2 cases were hydropic abortion. A stepwise logistic regression analysis indicated that, among seven criteria studied, three of them (shape of villi, prevalence of villi with three types of trophoblasts, and predominance of villi with hydropic change) were useful to differentiate complete hydatidiform mole from partial one. This observation may be applicable in the pathological diagnosis of the molar diseases.

Human leukocyte antigen-class II-negative long-term cultured human T-cell leukemia virus type-I-infected T-cell lines with progressed cytological properties significantly induce superantigen-dependent normal T-cell proliferation.

While most human T-cell leukemia virus type-I (HTLV-I)-infected T cells express abundant class II antigens, some aggressive-type adult T-cell leukemia (ATL) cells lose their expression. To investigate the significance of the class II antigen of HTLV-I infected cells, the progressiveness of HTLV-I-infected long-term cultured T-cell lines was evaluated, and then their antigen-presenting capacity was examined using a superantigen, staphylococcus enterotoxin B (SEB). Among the cell lines derived from peripheral blood, HPB-ATL-T (ATL-T), HPB-ATL-2 (ATL-2) and HPB-ATL-O were more progressed than Tax exclusively expressing HPB-CTL-I (CTL-I), because the former deleted p16 gene (polymerase chain reaction (PCR)) and strongly transcribed survivin (reverse transcriptase-PCR). Notably, interferon gamma-independent loss of class II expression of ATL-T and ATL-2 was found. In antigen-presenting experiments, however, both cell lines induced SEB-dependent significant T-cell proliferation estimated by [(3)H] thymidine uptake. No class II-re-expressed ATL-2 cells were observed in the SEB-presenting cultures by indirect immunofluorescence, and only minimum inhibition of SEB-dependent T-cell response by anti-human leukocyte antigen (HLA)-DR monoclonal antibody was observed. These findings suggest that both ATL-T and ATL-2 very effectively present SEB to T cells less dependently on class II molecules. These less immunogenic leukemic cells of aggressive ATL may contribute to disease aggression.

Expression of SV40 T antigen gene in the oligodendroglia induced primitive neuroectodermal tumor-like tumors in the mouse brain.

Primitive neuroectodermal tumors (PNET) are classified as the embryonal tumors developed in the brain, except for the cerebellum. Although many studies have been reported, the origin and pathogenesis of PNET are still unclear. In this study, we observed the development of undifferentiated tumors indistinguishable from PNET in the transgenic mice which expressed simian virus 40 T antigen (SV40-Tag) selectively in the oligodendroglia under the control of mouse myelin basic protein gene promoter. These PNET-like tumors reproducibly developed in the brain stem of the founder mice and the transgenic progeny derived from one founder mouse. Oligodendroglia-specific expression of SV40-Tag in these transgenic mice was observed by immunohistochemical analysis. Furthermore, expression of the oligodendroglia-specific marker genes was decreased in the tumors as well as in the transgenic brains. These findings suggested that tumors developed in transgenic mice were indistinguishable from PNET, and one of them showed oligodendroglia-like characteristics. Consequently, this transgenic line is a useful animal model to study the pathogenesis of undifferentiated tumor.

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.