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41.
Sugimoto T Kume S Osawa N Isshiki K Kanasaki K Tanaka Y Chin M Shibuya K Sakaguchi M Araki S Isono M Koya D 《Nihon Jinzo Gakkai shi》2005,47(4):463-467
A 31-year-old man was admitted to the hospital because of a low-grade fever, general malaise, nausea, vomiting, and a poor appetite. On admission his renal function was severely deteriorated (serum creatinine 16.12 mg/dl, BUN 163 mg/dl), and he had severe anemia (Hb 7.5 g/dl) and thrombocytopenia (67,000/microl). A radiological examination revealed the presence of multiple cysts in his kidneys bilaterally. The patient was diagnosed as having end-stage renal disease due to polycystic kidney disease, and hemodialysis was started on the day of admission. After the initiation of hemodialysis, his symptoms and laboratory tests improved, except for anemia and thrombocytopenia. He was noted to have marked splenomegaly and dilation of the portal vein, raising the suspicion of portal hypertension as the cause of the splenomegaly and pancytopenia. To treat his pancytopenia (anemia and thrombocytopenia) and to determine the reason for his portal hypertension, a splenectomy and open-wedge biopsy of the liver were performed. Histological findings in the liver included extensive fibrosis of the portal areas with an excess of moderately dilated bile ducts, compatible with a diagnosis of congenital hepatic fibrosis. After splenectomy, his red blood cell and platelet counts returned to normal, and he was discharged on maintenance dialysis. Congenital hepatic fibrosis is often associated with autosomal recessive polycystic kidney disease (ARPKD), but not with autosomal dominant polycystic kidney disease (ADPKD). However, both his mother and older brother had multiple renal cysts, indicating that this was an unusual case of ADPKD complicated by congenital hepatic fibrosis. 相似文献
42.
Hiroaki Sato Kentaro Kasai Toshiko Tanaka Toshiro Kita Noriyuki Tanaka 《Medical science monitor》2008,14(5):BR79-BR87
BACKGROUND: Hemorrhagic shock occasionally causes a fatal outcome following an outbreak of lung dysfunction, but the precise mechanism has not been clearly elucidated. Several studies have indicated that hemorrhagic shock causes a delayed vascular inflammatory decompensation and leads to inflammation-related organ dysfunction. Tumor necrosis factor (TNF)-alpha and interleukin (IL)-1beta are known as major proinflammatory cytokines that play an important role in excessive autolytic inflammation, finally inducing organ dysfunctions. In this study, the role of TNF-alpha and IL-1beta on lung dysfunction following hemorrhagic shock was examined by using FR167653, a potent inhibitor of TNF-alpha and IL-1beta production that acts by suppressing p38 mitogen-activated protein kinase (MAPK). MATERIAL/METHODS: Hemorrhagic shock was induced in anesthetized male rats by bleeding via a common carotid catheter for 20 minutes to 25% of total body blood volume without fluid resuscitation. Mean blood pressure, heart rate and arterial blood gas components were recorded up to 5 hours after the bleeding. The levels of TNF-alpha, IL-1beta and lactic dehydrogenase (LDH)-3 isozyme were measured in the serum of pulmonary venous blood. The lung tissue was excised for the assay of mRNA and for histopathological study. RESULTS: The expressions of mRNA for TNF-alpha and IL-1beta in the lung tissue and the concentrations of both cytokines in pulmonary serum increased after a hemorrhage. Inflammation-related injuries and function deterioration were observed in the lung following hemorrhagic shock. These hemorrhagic changes were inhibited by pretreatment with FR167653. CONCLUSIONS: TNF-alpha and IL-1beta play a key role in the development of inflammation-related lung dysfunction following hemorrhagic shock. Our model should be useful to explain the pathogenesis of lung dysfunction following hemorrhagic shock. 相似文献
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Paradoxical mineralocorticoid receptor activation and left ventricular diastolic dysfunction under high oxidative stress conditions 总被引:1,自引:0,他引:1
Wang H Shimosawa T Matsui H Kaneko T Ogura S Uetake Y Takenaka K Yatomi Y Fujita T 《Journal of hypertension》2008,26(7):1453-1462
BACKGROUND: Salt status plays a pivotal role in angiotensin-II-induced organ damage by regulating reactive oxygen species status, and it is reported that reactive oxygen species activate mineralocorticoid receptors. METHOD: To clarify the role of reactive oxygen species-related mineralocorticoid receptor activation in angiotensin-II-induced cardiac dysfunction, we examined the effect of the following: salt status; an MR antagonist, eplerenone; and an antioxidant, tempol in angiotensin-II-loaded Sprague-Dawley rats. RESULTS: Angiotensin-II/salt-loading elevated blood pressure, and neither eplerenone nor tempol antagonized the rise in blood pressure significantly. Left ventricular diastolic function was monitored by measuring peak velocity of a mitral early inflow (E), the ratio of mitral early inflow to atrial contraction related flow (E/A), deceleration time of mitral early inflow and -dP/dt, the time constant (T), and filling pressure (left ventricular end-diastolic pressure) by echocardiography or cardiac catheterization. Despite the suppressed serum aldosterone, left ventricular diastolic function was deteriorated with angiotensin II/high salt, but not affected by angiotensin II/low salt. However, angiotensin-II/salt-induced cardiac dysfunction was restored by eplerenone and tempol. Nicotinamide adenine dinucleotide phosphateoxidase-derived superoxide formation was greater in the hearts of the angiotensin II/high-salt rats than of the angiotensin II/low-salt rats. The expression of the Na(+) -H(+) exchanger isoform 1, a target of mineralocorticoid receptor activation, was significantly increased in the angiotensin II/high-salt group. Both tempol and eplerenone inhibited the angiotensin-II/salt-induced upregulation of Na(+) -H(+) exchanger isoform 1. CONCLUSION: These findings demonstrate that mineralocorticoid receptor activation by oxidative stress can cause left ventricular diastolic dysfunction in a rat model of mild hypertension. 相似文献
47.
Reactive oxygen species are considered to play a role in the development of diabetes mellitus and its complications. Human MTH1 (mutT homologue 1) has 8-oxo-7,8-dihydrodeoxyguanosine triphosphatase activity, which repairs oxidized forms of dGTP. This enzyme is known to have a thermolabile Met83 variant. We examined whether Val83Met polymorphism of human MTH1 gene is associated with type 1 diabetes mellitus. We recruited 156 type 1 diabetic patients (59 males and 97 females). The polymorphism was analyzed by restriction fragment length polymorphism analysis with Nsi I. The Met/Met genotype at codon 83 was very rare in both control and patient groups. Val/Met genotype tended to be more frequent in the whole type 1 diabetic patients than in controls. When subjects were divided into subgroups according to gender, there were no differences in the genotype and allele frequencies between patients and controls in males. On the other hand, in female type 1 diabetic patients, the Val/Met genotype was more frequent than in female controls (corrected P = 0.102). The Met allele was significantly more frequent in female type 1 diabetic patients than in female controls (corrected P = 0.022). Our results suggested that the Met allele at codon 83 of MTH1 gene might be involved in the development of type 1 diabetes mellitus in the Japanese female population. 相似文献
48.
Masaki Naganuma Atsushi Tachibana Takuya Fuchigami Sadato Akahori Shuichiro Okumura Kenichiro Yi Yoshimasa Matsuo Koichi Ikeno Toshiro Yonehara 《Journal of stroke and cerebrovascular diseases》2021,30(7):105791
ObjectivesThe Alberta Stroke Program Early Computed Tomography Score (ASPECTS) is a promising tool for the evaluation of stroke expansion to determine suitability for reperfusion therapy. The aim of this study was to validate deep learning-based ASPECTS calculation software that utilizes a three-dimensional fully convolutional network-based brain hemisphere comparison algorithm (3D-BHCA).Materials and MethodsWe retrospectively collected head non-contrast computed tomography (CT) data from 71 patients with acute ischemic stroke and 80 non-stroke patients. The results for ASPECTS on CT assessed by 5 stroke neurologists and by the 3D-BHCA model were compared with the ground truth by means of region-based and score-based analyses.ResultsIn total, 151 patients and 3020 (151 × 20) ASPECTS regions were investigated. Median time from onset to CT was 195 min in the stroke patients. In region-based analysis, the sensitivity (0.80), specificity (0.97), and accuracy (0.96) of the 3D-BHCA model were superior to those of stroke neurologists. The sensitivity (0.98), specificity (0.92), and accuracy (0.97) of dichotomized ASPECTS > 5 analysis and the intraclass correlation coefficient (0.90) in total score-based analysis of the 3D-BHCA model were superior to those of stroke neurologists overall. When patients with stroke were stratified by onset-to-CT time, the 3D-BHCA model exhibited the highest performance to calculate ASPECTS, even in the earliest time period.ConclusionsThe automated ASPECTS calculation software we developed using a deep learning-based algorithm was superior or equal to stroke neurologists in performing ASPECTS calculation in patients with acute stroke and non-stroke patients. 相似文献
49.
Yutaka Shigenaga Daisuke Takenaka Tomohisa Hashimoto Takayuki Ishida 《Magnetic resonance in medical sciences》2021,20(1):76
Purpose:The combination of modified Dixon (mDixon) and periodically rotated overlapping parallel lines with enhanced reconstruction sequence with two interleaved echoes, which promotes uniform fat-suppression and motion insensitivity, has recently become available for commercial magnetic resonance imaging (MRI) scanners. To compare the robustness of this combination sequence with that of standard Cartesian mDixon sequence for fat-suppressed T2-weighted imaging in clinical head and neck MRI.Methods:Fifty patients with head and neck tumors were involved this study. All patients underwent MRI using both the combination and standard sequences. Two radiologists independently scored motion artifacts and water–fat separation error using a 4-point scale (1, unacceptable; 4, excellent). Furthermore, comprehensive comparative evaluation was performed using a 5-point scale (1, substantially inferior; 5, substantially superior). Data were statistically analyzed using the Wilcoxon signed-rank test.Results:In the motion artifact assessment, ratings of 3 or 4 points were assigned to 45% (observer-1, 58.0%; observer-2, 32.0%) and 97% (100%; 94.0%) of images for the standard and combination sequences, respectively (P < 0.001). For the water–fat separation error assessment, ratings of 3 or 4 points were assigned to 100% (100%; 100%) and 85% (84.0%; 86.0%) of images, respectively (P < 0.001). In the comprehensive evaluation, of the 100 cases (observer-1, 50; observer-2, 50), 96 were rated at four or five points. In cases with slight or no motion artifacts and water–fat separation errors, the combination sequence was superior to the standard sequence in term of noise and sharpness, and equal in terms of contrast.Conclusion:Although water–fat separation errors increased significantly in the combination sequence, most of these were acceptable. The significantly decreased motion artifacts in the combination sequence significantly improved image quality overall. 相似文献
50.
Hiroo Takahashi Kaichiro Sawada Takatoshi Kakuta Takao Suga Kazuya Hanai Genta Kanai Satoshi Fujimura Noriyuki Sanechika Toshiro Terachi Masafumi Fukagawa Akira Saito 《Journal of artificial organs》2013,16(3):368-375
Bioartificial renal tubule devices (BTD) use cell therapy to improve conditions commonly observed in recipients of artificial kidneys for treatment of kidney diseases. We previously reported significant improvement of the condition of acute kidney injury (AKI) animals after treatment with BTD prepared with lifespan-extended human renal proximal tubular cells (hRPTEC). However, a major obstacle to use of BTD for patients is their biological safety, because hRPTEC are cultured in medium containing fetal calf serum. To establish the biological safety of BTD, we prepared BTD with lifespan-extended hRPTEC cultured in a newly developed serum-free medium and compared these with BTD prepared with hRPTEC cultured in serum-containing conventional medium. Lifespan-extended hRPTEC cultured in serum-free medium (hRPTEC-SFM) can proliferate similar to hRPTEC cultured in serum-containing conventional medium (hRPTEC-CM). Comparison of leakage and of reabsorption of small molecules for BTD prepared with hRPTEC-SFM (BTD-SFM) with those for our previous BTD prepared with hRPTEC-CM (BTD-CM) showed transportation in these two types of BTD was almost identical. When AKI goats were treated with BTD-SFM for 26 h, increase of survival time and reduction of cytokine expression in blood cells were almost same as for AKI goats treated with BTD-CM. Quantification of the expression of some genes of hRPTEC in BTD revealed significant changes during BTD treatment for AKI goats. In conclusion, lifespan-extended hRPTEC-SFM work as well as hRPTEC-CM, and the biological safety of BTD for patients could be elevated without loss of function by preparation from hRPTEC-SFM. 相似文献