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991.
Herpes simplex viral infection in human neonates: an immunohistochemical and electron microscopic study 总被引:1,自引:0,他引:1
Y Nakamura S Yamamoto S Tanaka H Yano G Nishimura Y Saito T Tanaka A Tanimura F Hirose S Fukuda 《Human pathology》1985,16(11):1091-1097
Specimens obtained at autopsy from six neonates with herpes simplex virus (HSV) infections were examined microscopically, electron microscopically, and immunohistochemically. Coagulative necrosis with inclusions was found in the livers and adrenal glands in all cases, as well as in various other organs, including the spleen, bone marrow, lungs, esophagus, tongue, and thymus, in some cases. Distinct hemorrhagic diathesis was found in three cases. No characteristic clinical findings, such as skin rashes or elevated titers of the antibody to HSV, were found, and clinical diagnosis was therefore difficult. In three cases isolation and typing of the causative virus were performed virologically, and type 1 HSV (HSV-1) was identified as the causative virus. Immunohistochemically, the type and distribution of the virus were evaluated in all cases with type-specific antisera to types 1 and 2 (HSV-2) antigens by the peroxidase-antiperoxidase method. In five cases the infections were found to be due to HSV-1 and in only one case to HSV-2. In the placenta in one case of HSV-2 infection, HSV antigen was demonstrated in the chorionic villi. Electron microscopic study confirmed the existence of viral particles in the placenta in that case and, thus, the possibility of a transplacental route of infection. 相似文献
992.
Fumio Inoue Hiroyuki Hasegawa Masahiko Nishimura Mariko Yanagisawa Arata Ichiyama 《Inflammation research》1985,16(5):295-301
The content of 5-hydroxytryptamine (5HT) in various tissues of mutant mouse (W/W
v) deficient in mast cells and of control mouse (+/+) was determined by high performance liquid chromatography. The depletion of mast cells in the mutant mouse (W/W
v) was expected to cause a decrease in the 5HT content. In the control mice, 5HT was most densely accumulated in the lung (9.66±5.23 g/g). Large intestine (6.40±2.61 g/g) and stomach (6.10±2.14 g/g) followed the lung in the rating of the 5HT content. The 5HT content ofW/W
v mice was only 23.4% and 4.1% that of the control in the stomach (p<0.01) and the skin (p<0.01), respectively. The results were consistent with the expectation. In other organs (small intestine, caecum, large intestine, brain, lung, blood and salivary gland), the difference between theW/W
v and normal mice was not statistically significant. The difference in the 5HT content of the stomach between the two genotypes was 4.67 g/g and was much larger than the 5HT content (0.49g/g) of normal mouse skin. With regard to the relatively small number of mast cells present in the stomach, the great difference in the 5HT content in the stomach between the two genotypes cannot be explained by the loss of mast cells. Hence, besides mast cells other cells may contribute to the high 5HT content of the stomach.This work was supported in part by grants from Takeda Science Foundation (1982), from the Ministry of Education, Science and Culture of Japan (Grant-in-Aid for Special Project Research. 1981–83) and from National Center of Nervous, Mental and Muscular Disorders (NCNMMD) of the Ministry of Health and Welfare, Japan (1981–83).To whom correspondence should be addressed 相似文献
993.
Tachikawa Y Matsushima T Abe Y Sakano S Yamamoto M Nishimura J Nawata H Takayanagi R Muta K 《European journal of haematology》2006,77(4):273-281
Notch signaling plays an important role in cell fate decisions in developmental systems. To clarify its role in committed hematopoietic progenitor cells, we investigated the effects of Notch signaling in erythroid colony forming cells (ECFCs) generated from peripheral blood. ECFCs express Notch receptors, Notch1 and Notch2, and Notch ligands Delta1, Delta4, and Jagged1. When we assayed the effects of Notch ligands on erythroid maturation by flow cytometry, we found that immobilized Delta1 and immobilized Delta4 in particular inhibited maturation, whereas Jagged1 had no effect. In addition, Delta4 inhibited proliferation without reducing cell viability. Increases in expression levels of the Notch target gene hairy enhancer of split (HES) -1 were evident by real-time PCR after stimulation with immobilized Delta4. The effect of soluble Delta4 on expression of HES-1 was less pronounced than that seen with the immobilized form, indicating that all surface-bound ligands are important for effective signal transduction. When ECFCs were cultured in the presence of soluble Delta4 at a low cell concentration, erythroid maturation was slightly inhibited, but at a high concentration, maturation was promoted via competition of soluble Delta4 with endogenous ligands. These results indicate a pivotal role of Notch signaling in regulating erythroid maturation and proliferation, and further suggest that cell-cell interactions modulate growth of erythroid progenitor cells via Notch system. 相似文献
994.
Grace Casaclang‐Verzosa Joseph F. Malouf Christopher G. Scott Eldyn Marcony Juracan Rick A. Nishimura Patricia A. Pellikka 《Echocardiography (Mount Kisco, N.Y.)》2010,27(2):105-109
Background: We assessed the hypothesis that diastolic function represented by left atrial size determines the rate of development of symptoms and the risk of all‐cause mortality in asymptomatic patients with severe aortic stenosis (AS). Methods: From a database of 622 asymptomatic patients with isolated severe AS (velocity by Doppler ≥ 4 m/sec) followed for 5.4 ± 4 years, we reviewed the echocardiograms and evaluated Doppler echocardiographic indices of diastolic function. Prediction of symptom development and mortality by left atrial diameter with and without adjusting for clinical and echocardiographic parameters was performed using Cox proportional‐hazards regression analysis. Results: The age was 71 ± 11 years and 317 (62%) patients were males. The aortic valve mean gradient was 46 ± 11 mmHg, and the Doppler‐derived aortic valve area was 0.9 ± 0.2 cm2. During follow‐up, symptoms developed in 233 (45%), valve surgery was performed in 290 (57%) and 138 (27%) died. Left atrial enlargement was significantly correlated with symptom development (P < 0.05) but the association diminished after adjusting for aortic valve area and peak velocity (P = 0.2). However, atrial diameter predicted death independent of age and gender (P = 0.007), comorbid conditions (P = 0.03), and AS severity and Doppler parameters of diastolic function (P = 0.002). Conclusion: Diastolic function, represented as left atrial diameter, is related to mortality in asymptomatic patients with severe AS. (ECHOCARDIOGRAPHY 2010;27:105‐109) 相似文献
995.
Recurrence of Helicobacter pylori infection and the long-term outcome of peptic ulcer after successful eradication in Japan. 总被引:8,自引:0,他引:8
Mitsuru Seo Mitsuo Okada Takuro Shirotani Hirokatsu Nishimura Kazuhiro Maeda Kunihiko Aoyagi Shotaro Sakisaka 《Journal of clinical gastroenterology》2002,34(2):129-134
Recurrence of peptic ulcer after successful eradication of Helicobacter pylori is closely associated with reinfection. The aim of this study was to examine the recurrence of peptic ulcer and reinfection with H. pylori after successful eradication. To eradicate H. pylori infection, patients with active peptic ulcer disease were assigned to two treatment groups depending on the year of their enrollment (AM group and OAMR group). Patients in the AM group received 400 mg of cimetidine twice per day, 300 mg of amoxicillin three times per day, and 250 mg of metronidazole three times per day for 2 weeks. Patients in the OAMR group received 20 mg of omeprazole once per day, 500 mg of amoxicillin granules three times per day, 250 mg of metronidazole three times per day, and 150 mg of roxithromycin twice per day for 1 week. After endoscopy verified ulcer scarring and successful eradication of H. pylori infection, study patients were followed up monthly and did not undergo acid-suppressive therapy. Endoscopy was performed at 6-month intervals for the 1st year. After the 1st year, follow-up endoscopies were performed annually. In total, 107 patients with peptic ulcer (duodenal ulcer [DU], 65; gastric ulcer [GU], 42) were followed up for a mean period of approximately 2 years. Recurrence of infection occurred in 10 (9.3%) of 107 patients (AM group, 9; OAMR group, 1) after 210 patient-years of follow-up; the recurrence rate was 4.8% per patient-year. Recurrence of H. pylori infection was significantly higher in the AM group (23.1%) than in the OAMR group (1.5%). H. pylori infection recurred in two patients 6 months after eradication therapy, in seven 1 year after, and in one 2 years after. Thereafter, no further cases of H. pylori recurrence were observed. During follow-up periods, seven cases of ulcer recurrence were observed (DU, 4; GU, 3). The rate of peptic ulcer recurrence within 2 years after eradication therapy was significantly higher than that after more than 2 years. Four cases of ulcer recurrence (DU, 3; GU, 1) also had recurrence of H. pylori infection. One recurrent case of DU without reinfection was associated with nonsteroidal anti-inflammatory drugs. The remaining two cases of GU recurred without H. pylori reinfection. In conclusion, peptic ulcer recurrence rarely occurred (3 [2.9%] of 103) in patients cured of H. pylori infection. Reinfection after apparent successful eradication was rarely noted when a powerful therapeutic regimen in eradication was used. Therefore, to eradicate H. pylori, a highly effective therapeutic regimen should always be used. 相似文献
996.
Kensei Gotoh Naoko Nishimura Yasunori Ohshima Yasuko Arakawa Haruki Hosono Yasuto Yamamoto Yasushi Iwata Kazumasa Nakane Keiji Funahashi Takao Ozaki 《Journal of infection and chemotherapy》2012,18(5):662-667
Rapid diagnosis of Mycoplasma pneumoniae pneumonia is required for treatment with effective antimicrobial agents without delay; however, this capacity has not yet been established in clinical practice. Recently, a novel nucleic acid amplification method termed loop-mediated isothermal amplification (LAMP) has been used to rapidly diagnose various infectious diseases. In this study, we prospectively evaluated the efficacy of the LAMP assay to rapidly diagnose M. pneumoniae pneumonia in clinical practice. Three hundred sixty-eight children (median age, 3.8 years; range, 0.1–14.3 years) admitted to our hospital between April 2009 and March 2010 for community-acquired pneumonia were enrolled in this study. We obtained throat swabs on admission to detect M. pneumoniae DNA and paired serum samples on admission and at discharge to assay M. pneumoniae antibody titers. M. pneumoniae pneumonia was diagnosed by either a positive LAMP assay or a fourfold or greater increase in antibody titer. Overall, 46 children (12.5% of the patients with pneumonia) were diagnosed with M. pneumoniae pneumonia; of these, 27 (58.7%) were aged less than 6 years. Of the aforementioned 46 children, 38 (82.6%) and 37 (80.4%) were identified by LAMP and serology, respectively. When the results of serology were taken as the standard, the sensitivity and specificity and positive and negative predictive values of the LAMP assay were 78.4%, 97.3%, 76.3%, and 97.6%, respectively. We concluded the LAMP assay may be useful for rapid diagnosis of M. pneumoniae pneumonia. 相似文献
997.
Carotid intima-media thickness is increased in subjects with ischemic heart disease having a familial incidence 下载免费PDF全文
Chiharu Kishimoto Miki Hirata Kaori Hama Masami Tanaka Kazushi Nishimura Shigeru Kubo Kinzo Ueda Tatsuo Fujioka Shunichi Tamakil 《Experimental & Clinical Cardiology》2006,11(1):8-10
OBJECTIVES: A family history of ischemic heart disease (IHD) is an independent risk factor for cardiovascular events. However, the mechanisms underlying this susceptibility have not been fully elucidated. The authors hypothesized that an important mediator of the familial incidence of IHD is subclinical atherosclerosis, which is detectable by noninvasive imaging. METHODS: One hundred forty-seven consecutive subjects (mean age 61.9 years, 57% men) were studied for one year using carotid ultra-sonogrophy for general medical screening, and familial IHD events were validated. Using a 7.5 MHz linear array transducer, carotid intima-media thickness (IMT) and carotid plaque were assessed. Subjects were subsequently divided into four groups based on the severity of IMT. RESULTS: The familial incidence of IHD and incidence of plaque were associated with the severity of IMT. No significant differences in risk factors were found between subjects with and without a family history of IHD. CONCLUSIONS: These findings suggest that subclinical atherosclerosis, as assessed in the carotid arteries, is more prevalent in individuals with a family history of IHD. 相似文献
998.
Arii K Ota K Suehiro T Ikeda Y Nishimura K Kumon Y Hashimoto K 《Diabetes research and clinical practice》2005,69(3):305-308
A 42-year-old woman with hypoglycemic symptoms that occurred several hours after a meal visited our hospital. The hypoglycemic symptoms appeared when she was 37 years old, and her plasma glucose level had been assessed as less than 60 mg/dL when she experienced the symptoms. One year before, she had been diagnosed with reactive hypoglycemia by 75 g-oral glucose tolerance test (OGTT), which showed a normal glucose tolerance (NGT) pattern, and had begun taking an alpha-glucosidase inhibitor and nutritional treatment. A 75 g-OGTT on admission showed hypoglycemia at 240 min after glucose loading, excessive insulin secretion and an impaired glucose tolerance (IGT) pattern. A euglycemic-hyperinsulinemic clamp study demonstrated decreased insulin sensitivity. Therefore, we suspected that she had reactive hypoglycemia associated with insulin resistance and treated her with 15 mg/day pioglitazone. Her hypoglycemic symptoms completely disappeared after treatment with pioglitazone; insulin sensitivity in a euglycemic-hyperinsulinemic clamp study improved. Another 75 g-OGTT revealed that the excessive insulin secretion and hypoglycemia at 240 min after glucose loading had disappeared, and glucose tolerance was normalized from an IGT pattern to an NGT pattern. Thus, we believe that pioglitazone is effective for reactive hypoglycemia and aggravated glycemic metabolism associated with insulin resistance. 相似文献
999.
Hong YH Nishimura Y Hishikawa D Tsuzuki H Miyahara H Gotoh C Choi KC Feng DD Chen C Lee HG Katoh K Roh SG Sasaki S 《Endocrinology》2005,146(12):5092-5099
It has recently been discovered that G protein-coupled receptors (GPCR) 41 and 43 are characterized by having the short chain fatty acids acetate and propionate as their ligands. The objective of this study was to investigate the involvement of GPCR41, GPCR43, and their ligands in the process of adipogenesis. We measured the levels of GPCR41 and GPCR43 mRNA in both adipose and other tissues of the mouse. GRP43 mRNA expression was higher in four types of adipose tissue than in other tissues, whereas GPCR41 mRNA was not detected in any adipose tissues. A high level of GPCR43 expression was found in isolated adipocytes, but expression level was very low in stromal-vascular cells. Expression of GPCR43 was up-regulated in adipose tissues of mice fed a high-fat diet compared with those fed a normal-fat diet. GPCR43 mRNA could not be detected in confluent and undifferentiated 3T3-L1 adipocytes; however, the levels rose with time after the initiation of differentiation. GPCR41 expression was not detected in confluent and differentiated adipocytes. Acetate and propionate treatments increased lipids present as multiple droplets in 3T3-L1 adipocytes. Propionate significantly elevated the level of GPCR43 expression during adipose differentiation, with up-regulation of PPAR-gamma2. Small interfering RNA mediated a reduction of GPCR43 mRNA in 3T3-L1 cells and blocked the process of adipocyte differentiation. In addition, both acetate and propionate inhibited isoproterenol-induced lipolysis in a dose-dependent manner. We conclude that acetate and propionate short chain fatty acids may have important physiological roles in adipogenesis through GPCR43, but not through GPCR41. 相似文献
1000.
OBJECTIVE: We determined whether chronic reductions in carotid blood flow elicit salt-sensitive hypertension through regulation of the brain renin-angiotensin system (RAS). DESIGN AND METHODS: Both internal carotid arteries of male Wistar rats were ligated over a 1-week period. Carotid-ligated or sham-operated rats were treated with a high-salt (8% NaCl diet and 1% NaCl drinking water) or low-salt (0.3% NaCl diet and distilled water) diet for 6 weeks. At the end of the experiment, expression of the RAS mRNAs in the brain was measured. Effects of a 6-day intracerebroventricular infusion of CV-11974, a selective non-peptide angiotensin II type 1 (AT1) receptor blocker, were investigated in carotid-ligated rats administered high-salt diet. RESULTS: High-salt administration increased systolic arterial pressure compared with low-salt administration in sham-operated rats [168 +/- 4 mmHg (n = 10) versus 149 +/- 3 mmHg (n = 10), P < 0.001] and in carotid-ligated rats [202 +/- 5 mmHg (n = 10) versus 153 +/- 2 mmHg (n = 10), P < 0.0001]. Systolic arterial pressure, urinary excretion of vasopressin and norepinephrine, and expression of renin, angiotensin I converting enzyme, and AT1 receptor mRNAs in the hypothalamus were greater in carotid-ligated rats than in sham-operated rats treated with high salt. In contrast, these parameters did not differ between carotid-ligated and sham-operated rats treated with low salt. Intracerebroventricular infusion of CV-11974 abolished the increase in these parameters in carotid-ligated rats treated with the high-salt diet. CONCLUSIONS: Chronic reductions in carotid blood flow may cause salt-sensitive hypertension in normotensive rats by activating the hypothalamic RAS. 相似文献