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101.
OBJECTIVE: In utero hematopoietic cell transplantation (IUHCT) typically achieves low-level mixed hematopoietic chimerism. However, the goal of IUHCT is to achieve therapeutic levels of chimerism. We hypothesized that prenatal adoptive immunotherapy might achieve high-level donor chimerism after IUHCT. MATERIALS AND METHODS: BALB/CE15 fetal mice were transplanted with a mixture of C57BL/6 (B6) T-cell-depleted bone marrow (TCD BM) cells and splenocytes from B6 mice presensitized to BALB/C alloantigen. The splenocytes were preincubated in L-leucyl-L-leucine methyl ester (LLME), to minimize graft vs host disease (GVHD). Recipients were followed after birth for donor cell chimerism and GVHD. RESULTS: Full donor hematopoietic chimerism following a single prenatal transplant was achieved in seven transplanted animals. Fully chimeric animals were healthy, without evidence of GVHD, and maintained their engraftment for the duration of the study (48 weeks). However, the addition of presensitized LLME-treated cells decreased survival until weaning relative to TCD BM alone, suggesting that some animals were lost to acute GVHD. Surviving chimeric animals demonstrated increased frequencies of T-regulatory cell populations in their spleen and BM, suggesting that they had successfully suppressed GVHD, allowing survival. CONCLUSIONS: This study represents "proof in principle" that prenatal immunotherapeutic strategies may achieve complete hematopoietic engraftment across full MHC barriers when combined with IUHCT. However, strategies with greater hematopoietic specificity must be developed prior to consideration of clinical application. 相似文献
102.
Sumino H Ichikawa S Miya Y Sakamaki T Kurabayashi M 《American journal of hypertension》2005,18(10):1340-1346
BACKGROUND: We investigated the role of angiotensin (Ang) II in maintaining blood pressure (BP) by administering a small dose of candesartan, an Ang II type 1 receptor antagonist, in postmenopausal women receiving long-term hormone replacement therapy (HRT). METHODS: A single dose of 2 mg of candesartan was administered orally to 13 normotensive postmenopausal women receiving HRT (continuous combined conjugated estrogen and medroxyprogesterone acetate orally; HRT group) and 13 normotensive postmenopausal women not receiving HRT (control group). Both BP and heart rate (HR) were measured at baseline and at 1, 2, 3, 4, 5, and 6 h after administration. Plasma renin activity (PRA) and Ang I, Ang II, and bradykinin concentrations were measured at baseline and 4 h after the administration of candesartan. RESULTS: Candesartan lowered the BP and raised the HR in both groups. However, the decrease in BP was significantly greater in the HRT group than in the control group (P < .05), whereas no significant difference in the change in HR was observed between the two groups. In the HRT group, significant increases were found in PRA, Ang I, and Ang II (all P < .05) and a significant decrease in bradykinin (P < .01) with candesartan treatment. In the control group, candesartan as associated with an increase in PRA (P < .05) but not in Ang I, Ang II, or bradykinin. CONCLUSIONS: Based on our study results, Ang II plays an important role in maintaining BP in normotensive postmenopausal women receiving HRT. Maintenance of BP may be dependent on the balance between the hypertensive effect of Ang II and the hypotensive effect of bradykinin. 相似文献
103.
Shuichi Miyakawa Shin Ishihara Tadahiro Takada Masaru Miyazaki Kazuhiro Tsukada Masato Nagino Satoshi Kondo Junji Furuse Hiroya Saito Toshio Tsuyuguchi Fumio Kimura Hideyuki Yoshitomi Satoshi Nozawa Masahiro Yoshida Keita Wada Hodaka Amano Fumihiko Miura 《Journal of hepato-biliary-pancreatic sciences》2008,15(1):7-14
No strategies for the diagnosis and treatment of biliary tract carcinoma have been clearly described. We developed flowcharts for the diagnosis and treatment of biliary tract carcinoma on the basis of the best clinical evidence. Risk factors for bile duct carcinoma are a dilated type of pancreaticobiliary maljunction (PBM) and primary sclerosing cholangitis. A nondilated type of PBM is a risk factor for gallbladder carcinoma. Symptoms that may indicate biliary tract carcinoma are jaundice and pain in the upper right area of the abdomen. The first step of diagnosis is to carry out blood biochemistry tests and ultrasonography (US) of the abdomen. The second step of diagnosis is to find the local extension of the carcinoma by means of computed tomography (CT), magnetic resonance imaging (MRI), magnetic resonance cholangiopancreatography (MRCP), percutaneous transhepatic cholangiography (PTC), and endoscopic retrograde cholangiopancreatography (ERCP). Because resection is the only way to completely cure biliary tract carcinoma, the indications for resection are determined first. In patients with resectable disease, the indications for biliary drainage or portal vein embolization (PVE) are checked. In those with nonresectable disease, biliary stenting, chemotherapy, radiotherapy, and/or best supportive care is selected. 相似文献
104.
Katoh S Lehtovirta M Kaprio J Harjutsalo V Koskenvuo M Eriksson J Tajima N Tuomilehto J 《The Journal of clinical endocrinology and metabolism》2005,90(5):2642-2647
The aim of this study was to evaluate genetic and environmental effects on plasma glucose, insulin secretion, and resistance in Finnish twins. Altogether 151 randomly selected twin pairs were examined by the oral glucose tolerance test; 66 twin pairs were monozygotic and 85 like-sexed dizygotic. We estimated the intraclass correlation coefficients and variance components of genetic and environmental effects on waist circumference, plasma glucose, and serum insulin. For fasting insulin, the proportion of total variation accounted for by additive genetic effects (A) and nonshared environmental effects (E) were 43 and 57%, respectively. As to postchallenge insulin and waist circumference, A effects were stronger in female twins (51 and 70%, respectively) than male twins in whom no significant evidence for genetic variance was found. Of the variation in fasting glucose, A and E effects accounted for 45 and 55%, respectively. Of the variation in postchallenge glucose, E effects had a greater role (65%), compared with A effects (35%); A effects on pre- and postchallenge insulin levels were highly correlated (genetic correlation coefficient = 0.81). In conclusion, additive genetic effects are important for the insulin secretion, whereas nonshared environmental effects contribute strongly to peripheral insulin resistance. 相似文献
105.
Ogura Sho Kimura Muneyoshi Takagi Shinsuke Mitsuki Takashi Yuasa Mitsuhiro Kageyama Kosei Kaji Daisuke Nishida Aya Taya Yuki Ishiwata Kazuya Yamamoto Hisashi Asano-Mori Yuki Yamamoto Go Uchida Naoyuki Wake Atsushi Taniguchi Shuichi Araoka Hideki 《European journal of clinical microbiology & infectious diseases》2021,40(5):941-948
European Journal of Clinical Microbiology & Infectious Diseases - The aim of this study is to clarify the characteristics of gram-negative bacteremia (GNB), including extended-spectrum... 相似文献
106.
Isabella Wimmer Cornelia Scharler Taro Kadowaki Sophie Hillebrand Barbara ScheiberMojdehkar Shuichi Ueda Monika Bradl Thomas Berger Hans Lassmann Simon Hametner 《Brain pathology (Zurich, Switzerland)》2021,31(2):333
Iron accumulation in the CNS is associated with many neurological diseases via amplification of inflammation and neurodegeneration. However, experimental studies on iron overload are challenging, since rodents hardly accumulate brain iron in contrast to humans. Here, we studied LEWzizi rats, which present with elevated CNS iron loads, aiming to characterise choroid plexus, ependymal, CSF and CNS parenchymal iron loads in conjunction with altered blood iron parameters and, thus, signifying non‐classical entry sites for iron into the CNS. Non‐haem iron in formalin‐fixed paraffin‐embedded tissue was detected via DAB‐enhanced Turnbull Blue stainings. CSF iron levels were determined via atomic absorption spectroscopy. Ferroportin and aquaporin‐1 expression was visualised using immunohistochemistry. The analysis of red blood cell indices and serum/plasma parameters was based on automated measurements; the fragility of red blood cells was manually determined by the osmotic challenge. Compared with wild‐type animals, LEWzizi rats showed strongly increased iron accumulation in choroid plexus epithelial cells as well as in ependymal cells of the ventricle lining. Concurrently, red blood cell macrocytosis, low‐grade haemolysis and significant haemoglobin liberation from red blood cells were apparent in the peripheral blood of LEWzizi rats. Interestingly, elevated iron accumulation was also evident in kidney proximal tubules, which share similarities with the blood–CSF barrier. Our data underscore the importance of iron gateways into the CNS other than the classical route across microvessels in the CNS parenchyma. Our findings of pronounced choroid plexus iron overload in conjunction with peripheral iron overload and increased RBC fragility in LEWzizi rats may be seminal for future studies of human diseases, in which similar constellations are found. 相似文献
107.
Chatachot Kotchakorn Shiratori Shuichi Chaiwatanarat Tawatchai Khamwan Kitiwat 《Annals of nuclear medicine》2021,35(11):1193-1202
Annals of Nuclear Medicine - This study aimed to determine the radiation dosimetry for 177Lu-PSMA imaging and therapy (I&T) in Thai patients who were treated for metastatic prostate cancer.... 相似文献
108.
Hayato Terayama Shuang-Qin Yi Shuichi Hirai Ning Qu Munekazu Naito Naoyuki Hatayama Shinichi Kawata Masahiro Itoh 《Anatomical science international / Japanese Association of Anatomists》2013,88(3):171-174
Although bilateral megaureters are not an infrequent occurrence in the urinary tract, bilateral megaureters associated with bilateral renal pelvis dilatation and a giant urinary bladder appear to be rare. In this paper, a cadaver case of an adult Japanese male with bilateral megaureters is described. In addition to describing and illustrating this case, the anatomy and etiology of these anomalous structures is discussed with a brief review of the literature. 相似文献
109.
Ryo Kodama Masayoshi Kato Shuichi Furuta Shouta Ueno Yugen Zhang Kuniharu Matsuno Chihiro Yabe‐Nishimura Eiji Tanaka Tohru Kamata 《Genes to cells : devoted to molecular & cellular mechanisms》2013,18(1):32-41
Activated oncogenes induce premature cellular senescence, a permanent state of proliferative arrest in primary rodent and human fibroblasts. Recent studies suggest that generation of reactive oxygen species (ROS) is involved in oncogenic Ras‐induced premature senescence. However, the signaling mechanism controlling this oxidant‐mediated irreversible growth arrest is not fully understood. Here, we show that through the Ras/MEK pathway, Ras oncogene up‐regulated the expression of superoxide‐generating oxidases, Nox1 in rat REF52 cells and Nox4 in primary human lung TIG‐3 cells, leading to an increase in intracellular level of ROS. Ablation of Nox1 and Nox4 by small interfering RNAs (siRNAs) blocked the RasV12 senescent phenotype including β‐galactosidase activity, growth arrest and accumulation of tumor suppressors such as p53 and p16Ink4a. This suggests that Nox‐generated ROS transduce senescence signals by activating the p53 and p16Ink4a pathway. Furthermore, Nox1 and Nox4 siRNAs inhibited both Ras‐induced DNA damage response and p38MAPK activation, whereas overexpression of Nox1 and Nox4 alone was able to induce senescence. The involvement of Nox1 in Ras‐induced senescence was also confirmed with embryonic fibroblasts derived from Nox1 knockout mice. Together, these findings suggest that Nox1‐ and Nox4‐generated ROS play an important role in Ras‐induced premature senescence, which may involve DNA damage response and p38MAPK signaling pathways. 相似文献
110.
Yoko Shibata Shuichi Abe Sumito Inoue Akira Igarashi Keiko Yamauchi Yasuko Aida Hiroyuki Kishi Keiko Nunomiya Hiroshi Nakano Masamichi Sato Kento Sato Tomomi Kimura Takako Nemoto Tetsu Watanabe Tsuneo Konta Yoshiyuki Ueno Takeo Kato Takamasa Kayama Isao Kubota 《International journal of medical sciences》2013,10(11):1530-1536
Background:Plasma fibrinogen is considered a biomarker of respiratory disease, owing to the relationship between plasma fibrinogen and pulmonary function established in Western populations. However, such a relationship has not yet been confirmed in an Asian population. We assessed this relationship in the general Japanese population.Methods:Totally, 3,257 men and women aged ≥40 years who participated in a community-based annual health checkup in Takahata, Japan, from 2004 to 2006, underwent spirometry, and their plasma fibrinogen levels were determined.Results:We found an inverse relationship between spirometric measures (percent predicted forced vital capacity [%FVC] and forced expiratory volume in 1s [%FEV1], and FEV1/FVC) and plasma fibrinogen levels in men, but not in women. The plasma fibrinogen levels were significantly higher in subjects with restrictive, obstructive, and mixed ventilatory disorders than in those with normal spirometry results. Multiple linear regression analysis revealed that in men, plasma fibrinogen levels were predictive for %FVC and %FEV1 (independent of age, body mass index, and cigarette smoking) but not for FEV1/FVC.Conclusions:Plasma fibrinogen was significantly associated with pulmonary function in Japanese men, and as such, plasma fibrinogen might be a potent biomarker for pulmonary dysfunction in men. 相似文献