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31.
In vivo MRI of cancer cell fate at the single-cell level in a mouse model of breast cancer metastasis to the brain. 总被引:7,自引:0,他引:7
Chris Heyn John A Ronald Soha S Ramadan Jonatan A Snir Andrea M Barry Lisa T MacKenzie David J Mikulis Diane Palmieri Julie L Bronder Patricia S Steeg Toshiyuki Yoneda Ian C MacDonald Ann F Chambers Brian K Rutt Paula J Foster 《Magnetic resonance in medicine》2006,56(5):1001-1010
Metastasis (the spread of cancer from a primary tumor to secondary organs) is responsible for most cancer deaths. The ability to follow the fate of a population of tumor cells over time in an experimental animal would provide a powerful new way to monitor the metastatic process. Here we describe a magnetic resonance imaging (MRI) technique that permits the tracking of breast cancer cells in a mouse model of brain metastasis at the single-cell level. Cancer cells that were injected into the left ventricle of the mouse heart and then delivered to the brain were detectable on MR images. This allowed the visualization of the initial delivery and distribution of cells, as well as the growth of tumors from a subset of these cells within the whole intact brain volume. The ability to follow the metastatic process from the single-cell stage through metastatic growth, and to quantify and monitor the presence of solitary undivided cells will facilitate progress in understanding the mechanisms of brain metastasis and tumor dormancy, and the development of therapeutics to treat this disease. 相似文献
32.
Kagayaki Kuroda Daisuke Kokuryo Etsuko Kumamoto Kyohei Suzuki Yuichiro Matsuoka Bilgin Keserci 《Magnetic resonance in medicine》2006,56(4):835-843
Referenceless, or self-reference, thermometry is a technique for mapping temperature differences in the region of interest (ROI) using the baseline phase estimated by extrapolating the field in the surrounding region for estimation (RFE) and subtracting the estimated baseline from the measured field. In the present work a self-reference technique based on complex field estimation using 2D polynomials comprising complex-valued coefficients was proposed and optimized. Numerical simulations with a Gaussian-profiled phase distribution demonstrated that the ROI radius had to be 2.3-2.5 times the standard deviation (SD) of the Gaussian function in order to keep the error below 8% of the peak phase change. The area ratio between the ROI and the RFE had to be larger than 2.0 to maintain the error level. Based on the simulations, and phantom and volunteer experiments, the complex-based method with independently optimized polynomial orders for the two spatial dimensions was compared with the phase-based method using the similar-order optimization strategy. The complex-based method appeared to be useful when phase unwrapping was not removed. Otherwise, the phase-based method yielded equivalent results with less polynomial orders. 相似文献
33.
The authors report on 48 patients with calculous pyelonephritis. Urinary obstruction was caused by renal calculi in 21 patients
and ureteral calculi in 27. Urine cultures were positive in 87.5% and bacteremia was seen in 70%. The common organisms in
urine and blood culture wereE. coli, Proteus and Klebsiella. Septic shock occurred in 10 (20.8%) out of 48 patients. Calculous pyelonephritis with urinary obstruction
is a very serious condition. 相似文献
34.
Kawashima Yoshiaki Cui Fude Takeuchi Hirofumi Niwa Toshiyuki Hino Tomoaki Kiuchi Katsumi 《Pharmaceutical research》1995,12(7):1040-1044
Purpose. Poorly compressible crystals of acebutolol hydrochloride were agglomerated by the spherical crystallization technique with a two-solvent system to improve the compressibility for direct tabletting. The mechanism of improvements in static compression behaviors and tablettabilities of the spherically agglomerated crystals were investigated.
Methods. The improvement of static compression behaviors of the agglomerated crystals was determined by measuring the stress relaxations and elastic recoveries of compressed powder of original and agglomerated crystals. The improved tablettability of agglomerated crystals was evaluated by the pressure transmission ratio upon compression, the ejection pressure for releasing the tablet from the die and the tablet strength, i.e., tensile strength required for breaking.
Results. The higher relaxation pressure and the lower elastic recovery of the agglomerated crystals than of the original crystals were found. The pressure transmission ratio data showed that the friction pressures of the two crystals were similar during the compression period. The ejection pressure of the agglomerated crystals was lower than that of the original crystals. The tensile strength of the tablet of agglomerated crystals was greater than that of the original crystals.
Conclusions. The compressibility and tablettability of the spherically agglomerated crystals prepared by the spherical crystallization technique were much improved due to their increased plastic property and reduced adhesive property compared to the original crystals. 相似文献
35.
Kazuhiko Sonoyama Haruaki Ninomiya Osamu Igawa Yasuhiro Kaetsu Yoshiyuki Furuse Toshihiro Hamada Junichiro Miake Peili Li Yasutaka Yamamoto Kazuhide Ogino Akio Yoshida Shin-ichi Taniguchi Yasutaka Kurata Satoshi Matsuoka Toshio Narahashi Goshi Shiota Yoshihisa Nozawa Hiroaki Matsubara Masatsugu Horiuchi Yasuaki Shirayoshi Ichiro Hisatome 《Hypertension research》2006,29(11):923-934
We examined the effects of angiotensin II (Ang II) on inward rectifier K+ currents (IK1) in rat atrial myocytes. [125I]Ang II-binding assays revealed the presence of both Ang II type 1 (AT1) and type 2 (AT2) receptors in atrial membrane preparations. Ang II inhibited IK1 in isolated atrial myocytes with an IC50 of 46 nmol/l. This inhibition was abolished by the AT, antagonist RNH6270 but not at all by the AT2 antagonist PD123319. Treatment of cells with pertussis toxin or a synthetic decapeptide corresponding to the carboxyl-terminus of Gialpha-3 abolished the inhibition by Ang II, indicating the role of a Gi-dependent signaling pathway. Accordingly, Ang II failed to inhibit IK1 in the presence of forskolin, dibutyryl-cAMP or protein kinase A catalytic subunits. In spite of the increased binding capacities for [125I]Ang II, Ang II failed to affect IKI in cells from spontaneously hypertensive rats (SHR). AT, immunoprecipitation from atrial extracts revealed decreased amounts of Gialpha-2 and Gialpha-3 proteins associated with this receptor in SHR as compared with controls. The reduced coupling of AT, with Gialpha. proteins may underlie the unresponsiveness of atrial IK1 to Ang II in SHR cells. 相似文献
36.
Hiroshi Yano Masahiro Murakami Yoshiaki Nakano Takeshi Tono Tadashi Ohnishi Takashi Iwazawa Yutaka Kimura Toshiyuki Kanoh Takushi Monden 《Digestive endoscopy》2004,16(4):343-346
We performed laparoscopic appendectomy and drainage to treat panperitonitis due to perforated appendicitis that occurred in a 28‐year‐old woman. We believe this is an appropriate procedure to treat perforated appendicitis because it is safe and minimally invasive, and faster recovery can be expected than after conventional open appendectomy. 相似文献
37.
SCG10 is a nerve growth factor (NGF)-inducible, neuron-specific protein whose expression is tightly correlated with axonal and/or dendritic growth. We have recently shown that the mRNA encoding SCG10 is expressed at significant levels in certain subsets of neurons in the adult rat brain, while its expression is undetectable or negligible in other non-neuronal tissues. Here we show that regional SCG10 mRNA expression in the adult mouse brain is comparable to that in the rat, however, in the hippocampus its expression profile is distinct. In the mouse, SCG10 mRNA is expressed at high levels in pyramidal cells of CA3–CA4 sub-fields of Ammon's horn and at low levels in the CA1–CA2 sub-fields, while it is found rather uniformly throughout the pyramidal cell layer of the rat hippocampus. SCG10 mRNA is not detectable in the dentate gyrus of the mouse hippocampus, although it is expressed in the rat dentate gyrus. Comparison with other mRNAs encoding neuronal growth-associated proteins (nGAPs) such as GAP-43, MAP2, α1-tubulin and stathmin suggests that dentate granule cells express a different repertoire of neuronal growth-associated genes in mouse and rat. 相似文献
38.
Masaki Q. Fujita Toshiyuki Yasui Bunzo Sato Naomi Uchida Kiyohisa Uchida Osamu Shiratori Kenichi Takeda Keishi Matsumoto 《Cancer science》1992,83(9):995-1001
Shionogi carcinoma 115 (SC115), an androgen-dependent mouse mammary tumor, rapidly loses its androgen responsiveness after androgen withdrawal. The growth of this tumor can also be stimulated by high doses of estrogen or glucocorticoid. In the present study, the maintenance of hormone-responsive growth of SC115 tumors with a high dose of estrogen was examined in castrated male mice using an SCI 15 subline obtained by serial transplantations of SCI 15 tumors in estrogen-treated castrated mice for 3 years (30 generations) (subline E2 ). Seed tumors from both SC115 and subline E2 could rapidly grow in castrated mice given daily injections of testosterone propionate (TP), 17β-estradiol (E2 ), or dexamethasone (Dex) (100 μg/mouse/day) but not in those given vehicle alone. Although SCI 15 and subline-E2 tumors grown with TP or Dex showed temporary regression after steroid withdrawal, the tumors grown with E2 did not show such temporary regression. The TP-, E2 -, or Dex-induced growth of subline-E2 tumors was almost the same as that of the original SCI 15 tumors. However, responsiveness to androgen, estrogen or glucocorticoid of both tumors disappeared within one passage in steroid-depleted castrated mice. The present findings demonstrate that the loss of responsiveness to androgen as well as to high doses of estrogen or glucocorticoid of SCI 15 tumors can be prevented in castrated mice not only with androgen but also with high doses of estrogen. 相似文献
39.
Kaoru Hatanaka Xiang-An Li Ling Guo Toshiyuki Sakata Judith A. Gillissen Akira Yoshioka Akira Yamamoto 《Thrombosis research》1994,74(6):643-654
We have experienced a coagulation factor VIII-deficient patient whose plasma has normal protein S (PS) activity and masses of free PS and its bound form in complex with C4b-binding protein (C4BP). Although the patient's plasma showed a normal ratio of free PS to PS-C4BP complex in the presence of 5 mM EDTA, the plasma gave an abnormally retarding major C4BP peak together with a major PS peak in the crossed immunoelectrophoresis (CIE) in the presence of 2 mM CaCl2. It was revealed that the major peak was formed by a mixture of PS-C4BP complex and free form. The addition of normal human plasma (NHP) to the patient's plasma inhibited the retardation of the major PS-C4BP complex. These suggest that the patient's plasma lacks some component(s) to inhibit Ca2+-dependent association of PS with C4BP. 相似文献
40.
Flow karyotypes and chromosomal DNA contents of genus Triticum species and rye (Secale cereale) 总被引:3,自引:0,他引:3
Jai-Heon Lee Youzhi Ma Toshiyuki Wako Lian Cheng Li Kee-Young Kim Seong-Whan Park Susumu Uchiyama Kiichi Fukui 《Chromosome research》2004,12(1):93-102
The flow cytometry and chromosome imaging method were jointly used for analyzing genome content and chromosomal DNA content of hexaploid wheat (AABBDD), hexaploid triticale (AABBRR), tetraploid wheat (AABB), and AA, BB, DD genome donors and RR genome rye. Their genome sizes were 34.4 pg, 40.9 pg, 26.2 pg, 12.1 pg, 13.7 pg, 10.5 pg, and 16.9 pg, respectively. The 2C nuclear DNA content of BB genome donor with 13.7 pg was the highest value among the other genome donors, AA or DD. The genome content of tetraploid wheat, unlike hexaploid wheat or hexaploid triticale, was larger than the sum of the genomes of AA and BB genome donors. The DNA content of each chromosome ranged from 1.22 pg in DD genome donor to 2.61 pg in rye. Each chromosome peak was divided into three to four groups. Only one chromosome was included in the highest chromosomal DNA peak in hexaploid wheat, tetraploid wheat, DD genome donor and rye but two chromosomes in AA, BB genome donors, and hexaploid triticale. Correlation between 2C nuclear DNA content and chromosome density volume was the highest value compared with the other chromosomal parameters of chromosome area, or chromosome length. 相似文献