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101.
Quantitative evaluation of the pulmonary microdistribution of TiO2 nanoparticles using X‐ray fluorescence microscopy after intratracheal administration with a microsprayer in rats 下载免费PDF全文
Guihua Zhang Naohide Shinohara Hirokazu Kano Hideki Senoh Masaaki Suzuki Takeshi Sasaki Shoji Fukushima Masashi Gamo 《Journal of applied toxicology : JAT》2015,35(6):623-630
The unevenness of pulmonary nanoparticle (NP) distribution, which hinders the establishment of an absolute dose–response relationship, has been described as one of the limitations of intratracheal administration techniques for toxicological assessment of inhaled NPs. Quantification of the NP microdistribution would facilitate the establishment of a concentration–response relationship in localized regions of the lung; however, such quantitative methods have not been reported. Here, we established a quantitative method for evaluating pulmonary TiO2 NP microdistribution in rats using X‐ray fluorescence microscopy. Ti intensity in lung sections from rats intratracheally administered 10 mg kg–1 TiO2 NPs with a microsprayer was measured using X‐ray fluorescence with a 100 µm beam size. Ti reference samples were prepared by dropping different concentrations of Ti solutions on glass slide or lung sections of untreated rat. Ti intensity increased linearly with Ti content in the reference samples on both substrates. The detection limit of TiO2 was estimated to be 6.3 ng mm–2. The reproducibility was confirmed for measurements done in the short‐ (2 weeks) and long‐term (6 months). The quantitative results of TiO2 NP microdistribution suggested that more TiO2 NPs were distributed in the right caudal and accessory lobes, which are located downstream of the administration direction of the NP suspension, and the lower portion of each lobe. The detection rates of TiO2 NPs were 16.6–25.0%, 5.19–15.6%, 28.6–39.2%, 21.4–38.7% and 10.6–23.2% for lung sections from the right cranial, middle, caudal, accessory and left lobes, respectively. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
102.
Sakamoto Kazumasa Ito Kiyoaki Yotsuyanagi Hiroshi Yatsuhashi Hiroshi Tanaka Yasuhito Hige Shuhei Takikawa Yasuhiro Ueno Yoshiyuki Yamamoto Kazuhide Imazeki Fumio Inoue Jun Kurosaki Masayuki Umemura Takeji Toyoda Hidenori Mita Eiji Michitaka Kojiro Maeshiro Tatsuji Yamada Norie Suetsugu Atsushi Kawanaka Miwa Seko Yuya Matsuura Kentaro Okumura Akinori Fukuzawa Yoshitaka Sugiyama Masaya Mizokami Masashi Yoneda Masashi 《Journal of gastroenterology》2022,57(12):971-980
Journal of Gastroenterology - Hepatitis B virus (HBV) is one of the most prevalent chronic viral infections that causes chronic hepatitis B (CHB). In Japan, genotypes B and C account for most of... 相似文献
103.
Terumi Kamisawa Ikuo Tabata Tomoaki Isawa Junichi Ishiwata Masashi Fukayama Morio Koike 《Journal of gastrointestinal cancer》1995,17(2):207-211
Summary A carcinoma in the dorsal part of the pancreas divisum with an annular pancreas in the anterior part is reported. A 79-yr-old
female was admitted in our hospital complaining of epigastralgia. Computed tomography (CT) and ultrasound (US) showed an irregular
mass in the pancreatic body. A pancreatogram obtained through the major duodenal papilla demonstrated only the ventral pancreatic
duct that encircled the duodenum. Contrast medium injected from the minor duodenal papilla showed Santorini’s duct obstruction
at the neck portion of the pancreas without communication with the ventral pancreatic duct. The patient died with liver metastases.
Autopsy confirmed annular pancreas and a 6-cm tumor in the pancreatic body extending to the pancreatic head and pancreas divisum.
Pancreatic carcinoma; histologically a moderately differentiated adenocarcinoma; originated from the dorsal part of pancreas
divisum. To our knowledge this is the first report of pancreatic carcinoma associated with annular pancreas coexistent with
pancreas divisum. 相似文献
104.
Influences of season and of temperature, photoperiod, and subcutaneous melatonin infusion on the glomerular filtration rate of ewes 总被引:1,自引:0,他引:1
Abstract: Influences of season and of temperature, photoperiod, and subcutaneous melatonin infusion on glomerular filtration rate (GFR) were measured in ewes. There was a seasonal difference of GFR between summer (June-August) and winter (December-February) in Tokyo (35°, 35°N); GFR was significantly ( P < 0.05) higher in summer (4.2 ± 0.3 ml/ min/kg) than in winter (3.0 ± 0.2 ml/min/kg). GFR was measured after exposure to three types of photoperiod, 24L: 0D, 12L: 12D, and 0L: 24D, for 7 to 8 days. The value for GFR obtained at 20°C was significantly lower ( P < 0.05) with 0L: 24D than with the other two photoperiodic conditions. GFR obtained during subcutaneous melatonin infusion (20μg/hr for 16 hr/ day for 7 days) with 24L: 0D conditions was significantly ( P < 0.05) lower (2.5 ± 0.1 ml/min/kg) than without infusion (3.8 ± 0.3 ml/ min/kg) and was about the same as that obtained in animals under 0L: 24D conditions. At 30°C, GFR exhibited no difference between the 3 photoperiodic conditions and was always lower than that found at 20°C. Possible influences of melatonin on GFR are discussed. 相似文献
105.
106.
Macrolides have immuno-modulatory effects as well as anti-bacterial effects. We successfully treated three idiopathic thrombocytopenic purpura (ITP) patients with clarithromycin (CAM). Case 1: A 69-year-old male ITP patient was treated with CAM at a dose of 400 mg/day. His platelet count increased from 5.6 x 10(4)/microliter to 10.1 x 10(4)/microliter. Case 2: A 72-year-old male ITP patient was treated with CAM at the same dose. The platelet count increased from 1.3 x 10(4)/microliter to 12.3 x 10(4)/microliter. Case 3: A 68-year-old female ITP patient was treated with CAM at the same dose. The platelet count increased from 2.3 x 10(4)/microliter to 13 x 10(4)/microliter. These facts suggest that CAM is useful in the treatment of ITP. 相似文献
107.
Masashi Mizokami Etsuro Orito Yukio Gibo Kaoru Suzuki Ken-ichi Ohba Tomoyoshi Ohno Johnson Y. N. Lau 《Liver international》1996,16(1):23-27
Abstract: To determine whether pretreatment HCV-RNA level, hepatitis C virus genotypes, alanine aminotransferase and histology correlate with subsequent response to interferon-α therapy or not, serum HCV-RNA levels and genotype were determined by branched DNA signal amplification assay and genotype-specific polymerase chain reaction in 43 patients with chronic active hepatitis C. Response to recombinant interferon-α 2α (504 million units in total) was defined as complete and sustained CR→SR, n=12), complete response followed by relapse (CR→Rel, n=17), and no response (NR, n=10), excluding dropouts (n=4). Patients who showed CR→SR had a lower HCV-RNA level (0.438 × 106 eq/ml) compared to CR→Rel (2.452 × 106 eq/ml, p=0.008) and NR (4.882 × 106 eq/ml, p=0.009). A higher proportion of patients with CR→SR had type 2a HCV (67%) compared to the CR→Rel (28%) and the NR (0%). There was a trend for type 1b hepatitis C virus infection to have higher serum HCV-RNA levels. There was no correlation between pretreatment HCV-RNA level and alanine aminotransferase. However, no relation between pretreatment HCV-RNA level and liver histology was observed; a high proportion of patients with CAH2a showed CR→SR, compared to those with CAH2b (p=0.001). Moreover, the patients with CAH2b who had low level hepatitis C virus viremia did not show CR→SR. These data indicate that pre-treatment serum HCV-RNA levels, genotype and liver histology are good predictors of subsequent response to interferon-α therapy in Japanese patients with chronic hepatitis C virus infection. 相似文献
108.
Shoji Ohno Takakiyo Nakaya Masashi Bando Yukihiko Sugiyama 《Nihon Kokyūki Gakkai zasshi》2007,45(10):759-765
A nationwide epidemiological survey of idiopathic interstitial pneumonias (IIPs) in 2005 was performed using clinical personal records. According to the data from the Japan Intractable Diseases Information Center, 4,396 patients with IIPs were covered by public insurance. The prevalence of IIPs in Japan was estimated to be 3.44 per 100,000. The forms of 1543 patients (new: 658, recurrent: 885) were collected. Of 1543 cases, 1322 cases (85.7%) had idiopathic pulmonary fibrosis (IPF), therefore details were investigated in patients with IPF. The mean age at onset was 65.4 years and men were more frequent than women (878 in men, 444 in women). The severity, diagnostic method, symptoms, imaging findings, and pulmonary function tests were analyzed in the new forms. Severity levels of I, II, III and IV were seen in 32, 28, 177, and 287 cases, respectively. A pathological diagnosis was made in 67 cases (12%). The positive rates of fine crackles, dry cough, exertional dyspnea, and finger clubbing were 98%, 94%, 98%, and 53%, respectively. On HRCT, honeycomb was noted in the subpleural lung lesions in more than 90% of the cases. As for pulmonary function tests, restrictive and diffusing capacity impairment were noted in 86% and 92%, respectively, and SpO2 was below than 90% in 91% on a 6-minute walking test. The serum KL-6 level was elevated in 95%. Most of the IPF analyzed cases were at a severity level of III or IV because the analysis aimed at those coverage by public insurance. Since this was only the initial nationwide epidemiological survey in Japan, the current situation should be investigated. 相似文献
109.
Naoto Komada Minako Yamagata Kazutaka Komura Katsuhiro Hayashi Toshihiro Maruyama Hiroaki Kataoka Masashi Koono Hirohito Tsubouchi 《Journal of gastroenterology》1997,32(1):95-101
We report an autopsy case of hepatocellular carcinoma (HCC) with sarcomatous change arising in the context of primary biliary cirrhosis (PBC) in a 79-year-old man. Primary biliary cirrhosis was diagnosed (stage I according to Scheuer's classification) by findings on blood biochemical analysis, laparoscopy, and liver biopsy at age 69 years. Five years later, (at age 74 years), a mass lesion was detected in the S6 region of the liver by abdominal ultrasonography, and target biopsy revealed well differentiated HCC. Blood biochemistry, ultrasonography, and computed tomography findings showed that the PBC had progressed to stage IV (cirrhotic stage). Percutaneous ethanol injection therapy (PEIT) was administered to the HCC several times over a 5-year period; however, the patient died of liver failure in February, 1994 (at age 79 years). Viral markers for hepatitis B and C were negative during the course, and hepatitis C virus RNA was not detected by polymerase chain reaction. Autopsy findings showed liver cirrhosis and diffuse involvement of spindle-shaped sarcomatoid cells in the liver, particularly in the S6 region, associated with several nodules of trabecular HCC cells. A zone of transition between the sarcomatoid cells and the trabecular hepatocellular carcinoma cells was observed. The sarcomatoid cells were diffusely disseminated in the peritoneal cavity and had metastasized to multiple organs. Immunohistochemically, the cells were positive for fibrinogen, as were the coexisting trabecular hepatocellular carcinoma cells. The HCC had been treated several times with PEIT. Of interest, PEIT may be an important factor in this type of tumor progression. 相似文献
110.
Masashi Takahashi Junya Fukuoka Norihisa Nitta Ryutaro Takazakura Yukihiro Nagatani Yoko Murakami Hideji Otani Kiyoshi Murata 《INT J CHRONIC OBSTR》2008,3(2):193-204
The term ‘emphysema’ is generally used in a morphological sense, and therefore imaging modalities have an important role in diagnosing this disease. In particular, high resolution computed tomography (HRCT) is a reliable tool for demonstrating the pathology of emphysema, even in subtle changes within secondary pulmonary lobules. Generally, pulmonary emphysema is classified into three types related to the lobular anatomy: centrilobular emphysema, panlobular emphysema, and paraseptal emphysema. In this pictorial review, we discuss the radiological – pathological correlation in each type of pulmonary emphysema. HRCT of early centrilobular emphysema shows an evenly distributed centrilobular tiny areas of low attenuation with ill-defined borders. With enlargement of the dilated airspace, the surrounding lung parenchyma is compressed, which enables observation of a clear border between the emphysematous area and the normal lung. Because the disease progresses from the centrilobular portion, normal lung parenchyma in the perilobular portion tends to be preserved, even in a case of far-advanced pulmonary emphysema. In panlobular emphysema, HRCT shows either panlobular low attenuation or ill-defined diffuse low attenuation of the lung. Paraseptal emphysema is characterized by subpleural well-defined cystic spaces. Recent topics related to imaging of pulmonary emphysema will also be discussed, including morphometry of the airway in cases of chronic obstructive pulmonary disease, combined pulmonary fibrosis and pulmonary emphysema, and bronchogenic carcinoma associated with bullous lung disease. 相似文献