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21.
We studied mechanism to induce scoliosis in Duchenne muscular dystrophy (DMD) by use of X-ray computed tomography (CT) of paraspinal muscles. CT examination of paraspinal muscles was performed on 15 DMD patients at the following six levels; 1. Th3 vertebrae (upper thoracic spine level) 2. Th6 vertebrate (middle thoracic spine level) 3. Th10 vertebrae (lower thoracic spine level) 4. L1 vertebrae (upper lumbar spine level) 5. L3 vertebrae (middle lumbar spine level) 6. L5 vertebrae (lower lumbar spine level). We evaluated the degeneration of paraspinal muscle by a decrease in radio-density of the muscle which indicates infiltration of fatty tissue. The degeneration of the lateral portion of paraspinal muscle was more marked than that of the medial portion. The muscle was most severely affected at the middle lumbar spine level, showing a tendency to increase degeneration at the lower level of the spine. In cases showing laterality of the degeneration of paraspinal muscle, the less affected muscle on CT was located at the convex site of scoliosis. We speculate that the scoliosis occurs when DMD patients have asymmetrical paraspinal muscle degeneration, leading them to take compensatory posture. 相似文献
22.
23.
Mariko Kobayashi Yukihiro Takahashi Makoto Ando Naoki Wada Masamitsu Murata Toshio Kikuchi 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2005,53(12):635-637
A 6 month-old male infant (weight: 4.5 kg) with congenital aortic stenosis underwent aortic valve replacement with a pulmonary
autograft (Ross procedure). The right ventricular outflow tract (RVOT) was reconstructed with a polytetrafluoroethylene (PTFE)-valved
equine pericardial conduit. At the age of 5, re-RVOT reconstruction with an equine pericardial patch bearing a PTFE monocusp
was required because of severe pulmonary stenosis resistant to 2 attempts of percutaneous transluminal pulmonary valvotomy.
Currently, at the age of 8, the degree of aortic regurgitation is trivial and the pulmonary autograft is free of functional
deterioration despite somatic growth. 相似文献
24.
Masaki Ando Tsuguo Igari Seiichi Ando Hirono Satokawa Hitoshi Yokoyama 《Annals of thoracic and cardiovascular surgery》2004,10(1):47-50
A 31-year-old adult with an aortico-left ventricular tunnel (ALVT) arising from the right aortic sinus is reported. Preoperative transesophageal echocardiography demonstrated a ruptured sinus of Valsalva with severe aortic valve regurgitation which originated from the right coronary sinus entering the outlet portion of the left ventricular outflow tract. Operation revealed the aortic entrance of the tunnel was above the right coronary sinus. Direct closure of the orifice of the tunnel using three stitches of 4-0 polypropylene with felt and aortic valve replacement (AVR) was performed. At 10-month follow-up the patient is asymptomatic and receiving no oral medications except anticoagulants. We believe this to be the oldest case of ALVT managed with AVR. 相似文献
25.
Deletion of Mycobacterium tuberculosis sigma factor E results in delayed time to death with bacterial persistence in the lungs of aerosol-infected mice 下载免费PDF全文
The stress-induced extracytoplasmic sigma factor E (SigE) of Mycobacterium tuberculosis shows increased expression after heat shock, sodium dodecyl sulfate treatment, and oxidative stress, as well as after phagocytosis in macrophages. We report that deletion of sigE results in delayed lethality in mice without a significant reduction of bacterial numbers in lungs. 相似文献
26.
Sakata N Sasatomi Y Ando S Meng J Imanaga Y Uesugi N Takebayashi S 《Connective tissue research》2000,41(2):117-129
Glycoxidative modification of various body proteins, including fibronectin (FN), has been shown to change their structural and functional properties, and be implicated in pathogenesis of diabetic complications. Little is known about the role of secondary structure of glycoxidative FN (gFN) in its domain functions. gFN was prepared by incubation with 25 and 200 mM glucose in 0.2 M sodium phosphate buffer at 37 degrees C on a shaking plate under aerobic and sterile conditions for various time intervals up to 49 days, being defined as gFN25 and gFN200, respectively. Unmodified FN (uFN) was prepared by incubation in 0.2 M sodium phosphate buffer without any glucose at 4 degrees C for 49 days. The extent of glycoxidative modification was examined using a noncompetitive enzyme-linked immunosorbent assay with an antibody against N(epsilon) -(carboxymethyl)lysine (CML), one of the major glycoxidation products. The binding activities of uFN and gFN to collagen, gelatin and heparin were determined by a solid phase enzyme immunoassay or heparin-affinity HPLC. Cell attachment was estimated by the extent of adhesion of FITC-labeled smooth muscle cells to uFN or gFN. Conformational change in gFN was detected by SDS-polyacrylamide gel electrophoresis and spectroscopy (circular dichroism). CML was detected in gFN25 and gFN200 after 49 and 21 days of incubation, respectively. Levels of CML were about six-fold higher in gFN200 than in gFN25 after 49 days. Both gFN25 and gFN200 showed a significant decrease in the ability of binding to collagen and gelatin after 7 days of incubation. The binding activity for heparin was significantly decreased in both gFN25 and gFN200 after one day. Cell attachment activity was reduced to 89% and 76% of the unmodified form in both gFN25 and gFN200 after 49 days, respectively. High molecular weight materials were found in gFN25 and gFN200 after 21 and 7 days, respectively. CD spectrum showed that gFN25 had lost its native conformation after 3 days of incubation, depending upon the concentration and incubation interval of the applied glucose. These in vitro results suggest that the loss of native conformation may reduce the domain functions of gFN, including binding activity to macromolecular ligands and cell attachment, and may play a major role in the pathogenesis of diabetic complications. 相似文献
27.
Katsumi Inoue Kenichi Abe Kenji Ando Shinichi Shirai Kei Nishiyama Michio Nakanishi Takashi Yamada Koyu Sakai Yoshihisa Nakagawa Naoya Hamasaki Takeshi Kimura Masakiyo Nobuyoshi Tadaomi Alfonso Miyamoto 《Cardiovascular pathology》2004,13(2):109-115
BACKGROUND: Angiographic regression of luminal narrowing occurs 6 months to 3 years poststenting. However, after 4 years lesions progressed gradually and late restenosis was observed in 28% of 179 Palmaz-Schatz-stented lesions during the past 10 years. Elucidating its pathogenesis is pivotal to developing preventive strategies. METHODS AND RESULTS: Histopathological and immunohistochemical studies were performed in 19 stented coronary arteries obtained from 19 patients autopsied after noncardiac death 2-7 years poststenting. The quality/severity of chronic inflammatory cells (T lymphocytes, macrophages and multinucleated giant cells) infiltration around the stent struts that is observed even in the absence of restenosis depended on the time elapsed from stenting: a) 2 years postprocedure, in spite of angiographic regression during the first year and pathologically expressed as maturation of the neointimal scar, there was chronic inflammatory response evidence: neovascularization and lymphocyte infiltration, b) > or = 3 years: the neointimal smooth muscle cells were sparse with abundant proliferation of collagen fibers. Presence of slight helper/inducer T lymphocytes and mild macrophage infiltration around the stent struts was evident immunohistochemically, c) > or = 4 years: prominent infiltration by lipid-laden macrophages with strong collagen-degrading matrix metalloproteinase immunoreactivity was observed around the struts. In two of these arteries, the surface contacting the stent was focally disrupted and covered by nonocclusive mural thrombi. CONCLUSIONS: Stainless steel stents evoke a remarkable foreign-body inflammatory reaction to the metal. These persistent peri-strut chronic inflammatory cells may accelerate new indolent atherosclerotic changes and consequent plaque vulnerability. 相似文献
28.
Yamazaki F Matsumura F Nagata J Ando A Imura T 《European journal of applied physiology》2001,85(3-4):208-213
The purpose of this study was to elucidate the effect of raised body temperature per se during acute heat stress on the spontaneous
arterial baroreflex control of heart rate (f
c) in humans. To investigate whether unloading of cardiopulmonary baroreceptors during whole-body heating would alter the arterial
baroreflex control of f
c, we controlled loading of the cardiopulmonary baroreceptors by head-down tilt (HDT) at angles of 5°, 10°, 15°, and 30° during
heat stress produced by hot-water-perfused suits. The sensitivity of the arterial baroreceptor-cardiac reflex was calculated
from the spontaneous changes in beat-to-beat arterial pressure and f
c. As an index of cardiopulmonary baroreceptor loading, the left atrial diameter (LAD) was measured by echocardiography. During
whole-body heating, the LAD decreased with the rising body core temperature and increased with the HDT. The decreased LAD
during heating almost recovered to the normothermic control level by 10° HDT. In the supine position, cardiac baroreflex sensitivity
remained unchanged during heating. Arterial pressure, f
c and cardiac baroreflex sensitivity were not changed by HDT ranging from 5° to 30° during heating. These results suggest that
cardiac baroreflex sensitivity remain unchanged during graded loading of the cardiopulmonary baroreceptors in heat-stressed
humans. Also, we conclude that the sensitivity of the spontaneous arterial baroreflex controlling the f
c is not influenced by raised body temperature per se during acute heat stress.
Electronic Publication 相似文献
29.
Cloning and nucleotide sequence of the gene encoding arginine deiminase of Mycoplasma arginini. 总被引:1,自引:1,他引:1 下载免费PDF全文
T Ohno O Ando K Sugimura M Taniai M Suzuki S Fukuda Y Nagase K Yamamoto I Azuma 《Infection and immunity》1990,58(11):3788-3795
The existence of a mycoplasmal arginine deiminase which catalyzes the conversion of L-arginine to L-citrulline has been postulated. Here we show the partial amino acid sequence of arginine deiminase of Mycoplasma arginini and the complete nucleotide sequence of the arginine deiminase gene of M. arginini. The open reading frame deduced from this sequence consists of 1,230 bp encoding 410 amino acids. The mature form of this enzyme contains 409 amino acids after the deletion of the first methionine. In this open reading frame, TGA nonsense codons are used as tryptophan codons; this usage was verified by determination of the amino acid sequence. The molecular weight of the enzyme calculated from the deduced amino acid sequence is 46,372. Recently, the nucleotide sequence of the arginine deiminase gene of M. arginini was reported by Kondo et al. (K. Kondo, H. Sone, H. Yoshida, T. Toida, K. Kanatani, Y.-M. Hong N. Nishino, and J. Tanaka, Mol. Gen. Genet. 221:81-86, 1990). However, their sequence differed from ours in several places and especially at the C terminus. 相似文献
30.