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31.
To evaluate the acute effects of anti-asthmatic drugs in vitro, we examined the modulation of various anti-asthmatic drugs in therapeutic concentrations on PAF-induced human eosinophil chemotaxis. Aminophylline (20 micrograms/ml) and Isoproterenol (10 nM) inhibited PAF (3 X 10(-8) M)-induced eosinophil chemotaxis nearly 30%, whereas no inhibitory effects were observed by Dexamethasone (0.1 microM), Tranilast, Ketotifen or Azelastine. Aminophylline (20 micrograms/ml) also inhibited LTB4 (3 X 10(-8) M)-induced eosinophil chemotaxis nearly 30%, whereas it did not inhibit chemotaxis induced by zymosan (5 mg/ml)-activated serum. These results indicate that anti-asthmatic drugs except for aminophylline and isoproterenol, when used acutely in therapeutic concentrations, have no striking inhibitory effects on PAF-induced eosinophil chemotaxis. These results further suggest the possibility that there are different mechanisms in eosinophil chemotaxis induced by PAF, LTB4 or by C5a. 相似文献
32.
Abstract Nitric oxide (NO) plays an important physiological role in regulating gastrointestinal motility. Involvement of endogenous NO was evaluated in the response to non-adrenergic, non-cholinergic (NANC) nerve stimulation of the dog sphincter muscle of Oddi. Transmural electrical stimulation (TES), nicotine (10?5M) and K+ (10 mM) produced only a relaxation in the sphincter muscle strips contracted with substance P, which was not potentiated by atropine. The TES-induced relaxation was abolished by tetrodotoxin (3 times 10?7 M) and oxyhaemoglobin (1.6 times 10?5 M), but not affected by atropine (10?7 M), propranolol (10?7 M), phentolamine (10?7 M), indomethacin (10?6 M), chole-cystokinin (CCK, 10?8 M) and vasoactive intestinal polypeptide (VIP, 10?8 M). The relaxation was also abolished by treatment with NG-nitro-L-arginine (L-NA, 10?5 M), an NO synthase inhibitor. Nicotine produced a transient relaxation, which was abolished by tetrodotoxin, hexamethonium (10?5 M) and L-NA, but not affected by atropine and NG-nitro-D-arginine (D-NA, 10?5 M). The addition of K+ elicited a transient relaxation, which was abolished by tetrodotoxin and L-NA. The inhibitory effects of L-NA were antagonized by L-arginine (10?3 M). The presence of neurons containing nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase was histochemically demonstrated in the sphincter of Oddi. These findings may indicate that TES, nicotine and K+ liberate NO from NANC inhibitory nerve which is involved in the relaxation of the dog sphincter of Oddi. The muscular tone does not seem to be regulated by cholinergic nerves under the experimental conditions used. 相似文献
33.
A Shinohara K Fukuda K Maeda F Ogushi S Sone T Ogura S Shinomiya 《Nihon Kyōbu Shikkan Gakkai zasshi》1991,29(9):1211-1215
A 63-year-old female, with a chief complaint of right chest pain was referred to our hospital because of an abnormal right chest wall shadow on chest X-ray. A rib tumor was suspected based on her chest CT scan. Percutaneous needle biopsy yielded a diagnosis of well-differentiated adenocarcinoma. As metastatic rib tumor was suspected, the primary tumor was sought for. A thyroid gland nodule was recognized by ultrasonography, and the cytological diagnosis was class V. Immunohistological demonstration of the thyroglobulin studies of the rib tumor tissue revealed papillary and trabecular patterns of cell arrangement and the presence of thyroglobulin existence. Definitive diagnosis of metastatic rib tumor from thyroid cancer was established. Immunohistological examination is useful to confirm the diagnosis of metastatic cancer of thyroid origin. 相似文献
34.
The purpose of this study was to investigate, during the performance of an object discrimination task, responses of neurons in the monkey hippocampal formation to the sight of several objects that have biological meaning, and compare these responses with those of amygdalar neurons studied previously using the same task. Neuronal activity in the hippocampal formation of conscious monkeys was recorded during performance of a task that led to presentation of familiar rewarding, familiar aversive, or unfamiliar objects. Of 864 neurons recorded in the hippocampal formation and adjacent cortices, 160 (18.5%) responded to the sight of a certain object(s). Responses to the sight of different kinds of objects were analyzed in detail. Nondifferential neurons (n = 73) responded to different objects with no significant difference in response magnitudes, and differential neurons (n = 87) responded to different objects with different response magnitudes. Of the differential neurons, 23 responded more strongly to rewarding objects than to other objects (rewarding-object-dominant neurons), but the magnitude of responses to objects did not necessarily correlates with the order of preferences to the objects as determined from observation of animal behavior. Aversive-object-dominant neurons (n = 13) responded more to aversive objects than to other objects. Unfamiliar-object-dominant neurons (n = 7) responded more to unfamiliar objects than to familiar objects. Selective neurons (n = 10) responded selectively to only one object or one category of objects. Fourteen of the rewarding- or averse-object-dominant neurons were tested in extinction or reversal trials. In 12 of 14 neurons, responses to a rewarding or aversive object did not change, or slightly weakened, in extinction or reversal trials. The results suggest the following. (1) Responses of rewarding- or aversive-object-dominant neurons may be involved in object-reward or object-aversion association. However, responses of many of these neurons might reflect past inputs to reinforcement rather than extant emotional processing. (2) Responses of unfamiliar-object-dominant neurons may be involved in recognition of objects based on their familiar or unfamiliar aspects. These results are further discussed and compared with responsiveness of amygdalar neurons. 相似文献
35.
Kiyoshi Uchide Hirohisa Ueno Noboru Takizawa Yasunori Okada 《Journal of bone and mineral research》2003,18(2):381-382
Matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) were measured in a mild case of dyssegmental dysplasia. X-ray pictures of a female baby born vaginally at 39 weeks of gestation showed short, bent, dumbbell-shaped long bones of the limbs and profound dyssegmental ossification in the spine, findings characteristic of dyssegmental dysplasia. When the levels of MMP-1, MMP-2, MMP-9, TIMP-1, and TIMP-2 were measured, the levels of MMP-2 and TIMP-1 were significantly reduced. This case might provide a clue to disclose the etiology of dyssegmental dysplasia. 相似文献
36.
Shigeharu Kimura Yoshimi Ohshige Liping Lin Tadashi Okumura Chizuko Yanaihara Noboru Yanaihara† Yahe Shiotani 《Journal of neuroendocrinology》1994,6(5):503-507
The localization of pituitary adenylate cyclase-activating polypeptide (PACAP) in the hypothalamus-pituitary system in rats was examined in light and electron microscopic immunocytochemistry using a specific antiserum to synthetic PACAP 1–38 (R0831). In light microscopic study, intensely PACAP-immunostained perikarya were observed in the supraoptic and paraventricular magnocellular nucleus in the hypothalamus. In the median eminence, many immunoreactive nerve fibers were observed in the internal layer, but a few immunoreactive terminals were noticed in the external layer. In the pituitary gland, numerous immunoreactive nerve fibers were observed in the posterior lobe. In the intermediate lobe, moderately immunostained cells were observed, but in the anterior lobe no immunostained cells were noticed. In electron microscopic study, PACAP-immunoreactivity was examined by avidin-biotin peroxidase complex method. In the perikarya of the supraoptic and paraventricular magnocellular nucleus, DAB-reaction products were distributed diffusely in the cytoplasmic matrix, frequently attaching to the rough-surfaced endoplasmic reticulum. In the nerve terminals of the posterior lobe, reaction products were observed among the secretory granules, but sometimes upon them. In the cells of the intermediate lobe, reaction products were also distributed in the cytoplasmic matrix. 相似文献
37.
Y. Fukuda T. Ishikawa H. Yahata S. Marubayashi K. Dohi 《Transplant international》1992,5(Z1):S596-S598
Since cyclosporin A (CsA), a widely used immunosuppressive drug, strongly suppresses interleukin-2 (IL-2) secretion, it is frequently difficult to estimate T lymphocyte activation in early acute rejection. We found that, when evaluated based on HLA-DQ antigen expression, monocyte activation in the peripheral blood of renal transplantation patients was a very sharp parameter in diagosing acute rejection. All of 16 episodes of early acute rejection, which were relatively easily suppressed by steroid pulse therapy, showed a sharp increase in the proportion of HLA-DQ antigen-positive monocytes (DQ+ mono) and a quick return of DQ+ mono to previous values, along with a fall in serum creatinine levels. Since, however, HLA-DR antigen-positive T lymphocytes (DR +T) were markedly increased over a long period in episodes of therapy-resistant and chronic rejection, their prolonged high value was regarded as a parameter indicative of poor prognosis. 相似文献
38.
Hideto SAKAI Kiichiro JINDE Noboru SAOTOME Wei SUNG Mitsunori YAGAME Yasuo NOMOTO Masanobu MIYAZAKI Takashi HARADA 《Nephrology (Carlton, Vic.)》1997,3(1):91-94
Summary: In situ hybridization of mRNA for collagen IV, collagen VI, stromelysin (MMP-3) and TIMP1 was examined in renal biopsy specimens from patients with IgA nephropathy (IgAN) or diabetic nephropathy with various degrees of tissue damage. The majority of cells in the glomeruli expressed these mRNA almost simultaneously, but a few cells demonstrated positive expression for only one of these probes. There was a parallel relationship between the degree of tissue damage and that of mRNA expressions of these probes in patients with IgAN, while patients with diabetic nephropathy showed a reverse relationship between these two parameters. It is concluded that patients with mesangial proliferative glomerulonephritis expressed mRNA for collagen collagenase and its inhibitor in the glomeruli in parallel with the progress of tissue damage. In contrast, glomerular samples from patients with diabetic nephropathy showed that there was an inverse relationship between tissue damage and expression of mRNA. It is concluded that expression of collagen, collagenase and its inhibitor parallels the progression of glomerular changes in IgAN, but such parallel expression was not observed in patients with diabetic nephropathy. 相似文献
39.
Masahito Minakawa Kenji Takahashi Norihiro Kondo Masaharu Hatakeyama Toshihiko Kuga Ikuo Fukuda 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2003,51(11):582-587
Objective: Reoperative coronary bypass grafting is at high risk. Particularly in redo cases where the patent graft is running near
the midline of the sternum, the graft may be exposed to injury by a median sternotomy and subsequent dissection. Whereas,
off-pump bypass grafting from the left axillary artery or descending thoracic artery by a left thoracotomy approach is safe
for preventing graft damage.Methods: From March 1998 to February 2002, we performed off-pump coronary artery bypass grafting by a left thoracotomy approach in
9 patients. The left axillary artery was used as the inflow vessel in 4 cases, and the descending thoracic, aorta in 5.Results: The radial artery was anastomosed proximally to the axillary artery in 4 cases and the descending thoracic aorta in one
case. The saphenous vein graft was anastomosed, proximally to the descending thoracic aorta in 4 cases. Transdiaphragmatic
minimally invasive bypass grafting for the right coronary artery was simultaneously performed in 3 cases. Postoperative cardiac
events were ventricular arrhythmia in 6 cases and supraventricular arrhythmia in 3 cases. There was no damage to the patent
grafts. Postoperative coronary angiography performed, in 8 cases revealed all the grafts to be patent without stenosis. Cardiac
symptoms were not found after the operation in any of the cases.Conclusions: These procedures can prevent the injury to patent grafts caused by a median sternotomy, and will be one of the useful strategies
for reoperative off-pump coronary artery bypass grafting. 相似文献
40.