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91.
Suppression of development of diabetes in NOD mice by lactate dehydrogenase virus infection 总被引:1,自引:0,他引:1
Izumi Takei Yoshiaki Asaba Tomohiro Kasatani Taro Maruyama Kenji Watanabe Tatsuo Yanagawa Takao Saruta Toshiharu Ishii 《Journal of autoimmunity》1992,5(6):665-673
It has been reported that lactate dehydrogenase virus (LDV) selectively infects a subpopulation of macrophages, thereby affecting the immune system. We studied the effects of LDV infection on the development of diabetes in non-obese diabetic (NOD) mice. Five-week-old female NOD mice were infected with LDV (10(8) ID50/mouse) and observed until 23 weeks of age. None of the 21-LDV-infected mice developed diabetes, whereas 10/14 (71.4%) uninfected mice did. Although the subpopulations of T cells and the percentage of Mac1-positive cells in the NOD murine spleen and the number of harvested peritoneal macrophages were unaffected by LDV infection, the proportions of Ia-positive peritoneal macrophages were significantly decreased in LDV-infected compared with uninfected mice (1.1 +/- 0.2%, 6.5 +/- 2.9%; P < 0.01). In LDV-infected NOD mice, insulitis of the same grade as that seen in uninfected NOD mice was observed. In another experiment, 3, 5, 10 or 16-week-old female NOD mice were infected with LDV. None of the mice infected with LDV at 3, 5 or 10 weeks of age developed diabetes and only one of six infected at 16 weeks of age did. These findings indicate that LDV infection suppresses the development of diabetes in female NOD mice by reducing the capacity of Ia-positive macrophages, and suggest that the development of human type 1 diabetes may be suppressed by certain viral infections. 相似文献
92.
Intending to clarify the true Incidence of Invasive lobular carcinoma of the breast In Japanese women as well as the frequency of unilateral multlcentriclty, 362 cases of clinically defined monocentrlc breast cancer without pre-operative biopsy (previously fine needle aspiration or needle biopsy were routinely carried out for every case) were examined by whole mammary gland serial sectioning. On the basis of pathology and the World Health Organization classification of breast tumors, each case was assigned to one of two main histologlc types: Invasive lobular carcinoma (ILC) or Invasive ductal carcinoma (IDC). Invasive lobular carcinoma was further separated into classic and variant types by employing previously published criteria. Twenty-one cases of ILC (5.8%) were diagnosed, which Is more than In most previous Japanese studies. Unilateral multicentric breast carcinoma was detected In 9.5% of ILC and 16.1% of IDC (the difference was found not significant). Microscopically, ILC tumors were found to be, on average, larger than IDC. Patients with classic type ILC tended to be younger than those with variant type or IDC. Estrogen receptor expression was found more frequently In variant type ILC than in classic type. These results suggest that the incidence of invasive lobular carcinoma of the breast In Japanese women is low and that unilateral multicentricity Is not significantly higher in ILC than in IDC. 相似文献
93.
R Kawaguchi Y Shibuya U Ogasa O Kosuda K Hikiji K Ishii 《Rinsho byori. The Japanese journal of clinical pathology》1992,40(11):1198-1203
Six kinds of human herpes viruses have been identified and classified on the basis of structure and characteristics. We studied the identification and classification of these types using PCR to amplify the virus-specific DNA sequences. This method showed higher sensitivity than the conventional method of virus isolation and culture for HSV and CMV detection. For each positive control, the viral DNA was amplified only when the complementary primers themselves were used. PCR apparently detects only the activated virus, because normal controls were negative when this method was used. Therefore, the present method is thought to closely reflect viral activation and infectious diseases in patients with latent infections. 相似文献
94.
WSX-1 is required for resistance to Trypanosoma cruzi infection by regulation of proinflammatory cytokine production 总被引:6,自引:0,他引:6
Hamano S Himeno K Miyazaki Y Ishii K Yamanaka A Takeda A Zhang M Hisaeda H Mak TW Yoshimura A Yoshida H 《Immunity》2003,19(5):657-667
WSX-1 is a class I cytokine receptor with homology to the IL-12 receptors and is essential for resistance to Leishmania major infection. In the present study, we demonstrated that WSX-1 was also required for resistance to Trypanosoma cruzi. WSX-1-/- mice exhibited prolonged parasitemia, severe liver injury, and increased mortality over wild-type mice. WSX-1-/- splenocytes produced enhanced levels of Th2 cytokines, which were responsible for the prolonged parasitemia. Massive necroinflammatory lesions were observed in the liver of infected WSX-1-/- mice, and IFN-gamma that was overproduced in WSX-1-/- mice compared with wild-type mice was responsible for the lesions. In addition, vast amounts of various proinflammatory cytokines, including IL-6 and TNF-alpha, were produced by liver mononuclear cells in WSX-1-/- mice. Thus, during T. cruzi infection, WSX-1 suppresses liver injury by regulating production of proinflammatory cytokines, while controlling parasitemia by suppression of Th2 responses, demonstrating its novel role as an inhibitory regulator of cytokine production. 相似文献
95.
Structural changes in the developing rat lung were studied by a combined use of light microscopy including immunohistochemistry for a-smooth muscle actin (alpha-SMA) and scanning electron microscopy (SEM) using the KOH-collagenase digestion method. In the embryonic stage (E11-E13), the lung bud appeared as an outgrowth from the ventral wall of the foregut which grew caudally into the splanchnic mesoderm to form a pair of bronchial buds at the end. At E13, the airway smooth muscle cells first appeared around the bifurcation of the trachea. These smooth muscle cells were restricted to the dorsal surface of the tracheal epithelium, suggesting a difference in character between the dorsal and ventral sides of the mesenchymal cells in this region. During the pseudoglandular stage (E13-E18.5), the bronchial buds repeatedly gave off branches in the mesenchymal tissue. The smooth muscle cells in the bronchioles were spindle-shaped and arranged completely circularly around the epithelial tube, except that the terminal bud of bronchioles lacked the smooth muscles. The neck of the terminal bud was constantly surrounded by flat and irregularly-shaped immature smooth muscle cells, representing an early event in the smooth muscle cell differentiation from mesenchymal cells. In the canalicular to saccular stages (E18.5 to birth), the terminals of bronchioles became saccular, thus forming prospective alveolar acini. At birth, the alveolar wall became thinner than before birth, and the individual smooth muscle cells in bronchioles were elongated like a tape. As to the blood vessel differentiation, various sized sinusoidal spaces indicating the primitive blood vessels were already present in the mesenchymal tissue at E11.5. The endothelial cells of these sinusoidal spaces were irregularly shaped and sometimes extended their processes into the lumen. The network of tubular vessels appeared from E14.5. These vessels had tapering ends as well as transluminal trabeculae, suggesting that capillary growth proceeds by both the sprouting and partitioning (i.e., intussusception) of vessels in the pseudoglandular stage. 相似文献
96.
The surface ultrastructure of excysted metacercariae of five species of Japanese lung flukes: Paragonimus westermani, P. pulmonalis, P. miyazakii, P. ohirai and P. iloktsuenensis, were studied. Some differences were observed in the distribution of the spines and papillae among the five species. Single-pointed spines were generally developed in the antero-ventral region, and their development varied among species. Three morphological types of papillae were observed: large-domed, small-domed and pit type. Large-domed papillae were regularly located on the lip of suckers without variation among the five species. The small-domed and pit type papillae were arranged bilaterally and symmetrically on the body surface, and the distribution varied among the species, especially around the suckers. These results suggest that metacercariae of Paragonimus species can be distinguished by surface ultrastructure, especially by the distribution of papillae. 相似文献
97.
Molecular evidence for multicentric development of thyroid carcinomas in patients with familial adenomatous polyposis
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Miyaki M Iijima T Ishii R Hishima T Mori T Yoshinaga K Takami H Kuroki T Iwama T 《The American journal of pathology》2000,157(6):1825-1827
Familial adenomatous polyposis is characterized by multiple colorectal adenomas and an increased incidence of colorectal carcinomas. Patients also develop various extracolonic tumors, of which, thyroid carcinoma is common in young females. The occurrence of multiple carcinomas in one thyroid is frequently observed, although some carcinomas are solitary. To clarify whether each carcinoma develops independently or metastatically spreads from the first one formed, we analyzed the adenomatous polyposis coli (APC) gene mutation in each carcinoma. We found that each carcinoma had a different somatic mutation of the APC gene. This is molecular confirmation for the multicentric development of thyroid carcinomas in familial adenomatous polyposis through biallelic inactivation of the APC gene. 相似文献
98.
F Kametani K Tanaka M Sato S Haga T Saitoh T Shinoda T Ishii 《Neuroscience letters》1990,117(1-2):62-67
We have previously described a monoclonal antibody Hy20-54-16-3L raised against crude primary (AL) amyloid fibrils that preferentially labelled amyloid deposits in the brains of patients with Alzheimer's disease (AD) (Ishii et al., Neuropathol. Appl. Neurobiol., 12 (1986) 441-445). In the present study, we analyzed the protein from an AL-amyloid laden spleen by gel filtration and SDS-PAGE; a partial amino acid sequence of the Hy20-54-16-3L-immunoreactive band excised from Western blots was determined and found to be a lambda light chain of human immunoglobulins. Additionally we have confirmed that this monoclonal antibody reacts with amyloid in AD brain by using a peroxidase-linked immunoelectron microscope technique. It is concluded that an epitope shared with a lambda light chain is included in or associated with amyloid deposits in the AD brain. 相似文献
99.
Emiko Ono Yuji Maeda Hidenori Tanimoto Yuma Fukutomi Chiyako Oshikata Kiyoshi Sekiya Takahiro Tuburai Naomi Turikisawa Mamoru Otomo Masami Taniguchi Houta Ishii Akihiko Asahina Eishi Miyazaki Tosihide Kumamoto Kazuo Akiyama 《Arerugī》2007,56(6):587-592
BACKGROUND: Recently, it is recognized that the patients of oral allergy syndrome (OAS) to fruits are increasing. However, there are little knowledges of the background, character, and seriousness about these patients in Kanto regions. OBJECTIVE: We aimed to investigate the clinical features of OAS patients to plant origin foods in Kanto regions. METHODS: The patient, who visited Sagamihara National Hospital from 2000 to 2005 and developed some allergic symptoms to plant origin foods, were studied by a questionary survey. RESULTS: As for the 42 subjects, average age are 36 years old, male:female=8:34, merger of other allergic disease is 35 allergic rhinitis of 42 subjects (83%), 34 of asthma (81%), 14 of atopic dermatitis (33%). The causes of OAS symptoms are 32 rose-family fruits, 34 non-rose family fruits, 14 vegetables, 11 nuts, 2 grains subjects. As for the symptom, only in the oral and pharynx symptoms are found in 12, the systemic symptoms is 29, anaphylaxis is 11 subjects. Allergic rhinitis preceded on the 90% subjects with pollinosis, very high rate. On the other hand, the 20% of all subjects have no symptoms of allergic rhinitis. CONCLUSION: A nasal catarrh symptoms went ahead in most of the OAS subjects in Kanto regions. In addition, considering from some patients have no black alder pollinosis and/or are allergic to many non-rose-family fruits at high frequency, there might be a broad cross-reactivity between many pollens other than alder and plant origin foods. 相似文献
100.
Soichiro Yamamoto Wataru Yasui Yasuhiko Kitadai Hiroshi Yokozaki Ken Haruma Goro Kajiyama Eiichi Tahara 《Pathology international》1998,48(7):499-506
Vascular endothelial growth factor (VEGF), also known as vascular permeability factor, is a secreted protein which may play a pivotal role in tumor-associated microvascular angiogenesis and hyperpermeability. The expression of mRNA for VEGF was examined in eight gastric carcinoma cell lines and 30 gastric carcinoma tissues as well as corresponding normal mucosa. All the cell lines expressed VEGF mRNA at various levels that correlated well with the amounts of VEGF secreted into the condition medium. The expression of VEGF mRNA by TMK-1 cells was increased by the treatment of epidermal growth factor (EGF) or interleukin-1α (IL-1α), whereas it was decreased by the treatment of interferon-β (IFN-β). In gastric carcinoma tissues, the level of VEGF mRNA in primary tumors was higher than that in the corresponding normal mucosas in six (46%) of 13 well-differentiated adenocarcinomas and in two (12%) of 17 poorly differentiated adenocarcinomas, respectively. Vessel counts in well-differentiated adenocarcinomas had a tendency to be higher than those in poorly differentiated adenocarcinomas. In well-differentiated adenocarcinomas, the levels of VEGF mRNA expression tended to be higher in carcinomas of advanced stage than in early stage carcinomas. Both in situ mRNA hybridization and immunohistochemistry demonstrated the presence of VEGF expression within the tumor cells. These results suggest that VEGF may confer angiogenesis and progression of human gastric carcinomas, especially of the well-differentiated type. 相似文献