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21.
S. Kudo K. Umehara Yoshifumi Abe Masayuki Furukawa Masaaki Odomi 《Psychopharmacology》1997,131(4):388-393
To elucidate the penetrability of carteolol, a β-adrenoceptor antagonist (β-blocker) into the brain of rats, intracerebral
and serum concentrations of the compound were determined in male rats receiving single or repetitive oral administration of
carteolol hydrochloride at 30 mg/kg. The time-course of the intracerebral concentration of carteolol following single IV administration
of the compound at 10 and 30 mg/kg was also studied in male rats. A high-performance liquid chromatography method was used
to determine the intracerebral and serum concentrations. Following single oral dosing, the intracerebral concentration of
carteolol reached a maximum of 0.074 μg/g at 2 h postdosing and declined with a half-life of 3.7 h, and the Cmax and AUC of carteolol in the brain were 12.5% and 19.8% of those in serum. The intracerebral and serum concentrations of carteolol
were determined in male rats receiving repetitive oral dosing of the compound once daily for 7 days. The concentration of
carteolol in the brain and serum at 1 h postdosing varied within a range of 0.059–0.091 μg/g and 0.321–0.443 μg/ml, respectively,
throughout the dosing period, showing no changes in the penetrability of the compound into the brain due to repeated dosing.
The concentration of carteolol in the brain and serum increased in a dose-dependent manner in rats receiving a single IV administration
of the compound. The elimination half-life of carteolol in the serum and brain was 0.6–0.8 h and 1.3–1.7 h, respectively,
in rats following single IV dosing of the compound. The half-life in the brain was about twice as long as that in the serum.
The brain to serum concentration ratio was 0.306:0.499. From the above results, it was concluded that carteolol is distributed
from the circulation to the brain with low penetrability.
Received: 30 October 1996/Final version: 16 December 1996 相似文献
22.
23.
Patricia Kudo Katie Dainty Michael Clarfield Larry Coughlin Pauline Lavoie Constance Lebrun 《Journal of orthopaedic research》2006,24(2):115-123
Despite numerous publications and clinical trials, the results of treatment of recalcitrant chronic plantar fasciitis with extracorporeal shockwave therapy (ESWT) still remain equivocal as to whether or not this treatment provides relief from the pain associated with this condition. The objective of this study was to determine whether extracorporeal shock wave therapy can safely and effectively relieve the pain associated with chronic plantar fasciitis compared to placebo treatment, as demonstrated by pain with walking in the morning. This was set in a multicenter, randomized, placebo-controlled, double-blind, confirmatory clinical study undertaken in four outpatient orthopedic clinics. The patients, 114 adult subjects with chronic plantar fasciitis, recalcitrant to conservative therapies for at least 6 months, were randomized to two groups. Treatment consisted of approximately 3,800 total shock waves (+/-10) reaching an approximated total energy delivery of 1,300 mJ/mm(2) (ED+) in a single session versus placebo treatment. This study demonstrated a statistically significant difference between treatment groups in the change from baseline to 3 months in the primary efficacy outcome of pain during the first few minutes of walking measured by a visual analog scale. There was also a statistically significant difference between treatments in the number of participants whose changes in Visual Analog Scale scores met the study definition of success at both 6 weeks and 3 months posttreatment; and between treatment groups in the change from baseline to 3 months posttreatment in the Roles and Maudsley Score. The results of this study confirm that ESWT administered with the Dornier Epos Ultra is a safe and effective treatment for recalcitrant plantar fasciitis. 相似文献
24.
Kenji Yoshimi Masatoshi Takeda Tsuyoshi Nishimura Takashi Kudo Yu Nakamura Kunitoshi Tada Nobuyoshi Iwata 《Brain research》1991,560(1-2):149-158
Changes in MAP2 and clathrin immunoreactivity were studied in gerbil hippocampus after transient cerebral ischemia. MAP2 immuno-reactivity decreased significantly by 1 h in the subiculum-CA1 and CA2 areas which correspond to reactive change, while no decrease was observed in CA1 until day 4. Before the initiation of delayed neuronal death, MAP2 immunoreactivity was not changed in CA1. On the other hand clathrin immunoreactivity increased in the pyramidal cell layer of CA1 by 3 h after ischemia and remained high for 2 days. Clathrin immunoreactivity in the pyramidal cell layer of CA1 diminished after delayed neuronal death. The transient change of clathrin was noted especially in CA1 in the period prior to delayed neuronal death. These results imply an abnormal change in clathrin turnover after ischemia, which may participate in the pathogenesis of delayed neuronal death. 相似文献
25.
M Yasujima K Abe M Kohzuki M Tanno Y Kasai M Sato K Omata K Kudo K Takeuchi K Yoshinaga 《Japanese circulation journal》1986,50(11):1185-1190
To assess the pathophysiological role of atrial natriuretic factors in the regulation of blood pressure, we studied the effect of chronic infusion of a synthetic atrial natriuretic factor of 25 amino-acid residues on blood pressure and sodium-water excretion. Experimental subjects were rats with hypertension made by chronic infusion of vasopressin on regular intakes of sodium or on sodium loading with 1% NaCl as drinking water. When a subdepressor dose (150 micrograms/kg/day) of synthetic atrial natriuretic factor was delivered via an osmotic minipump into the jugular vein simultaneously with 7.2 U/kg/day of vasopressin infused intraperitoneally by another osmotic minipump, the expected elevation of systolic blood pressure was completely inhibited. This was not accompanied by any changes in urine volume and urinary sodium excretion. The antihypertensive effect was sustained throughout the experimental period lasting 3 days in rats on regular sodium intake (p less than 0.01) or on sodium loading with 1% NaCl as drinking water (p less than 0.01). These results indicate that a subdepressor dose of synthetic atrial natriuretic factor can modulate the vasopressor effect of vasopressin. Therefore it is suggested that an atrial natriuretic factor may be involved in the regulation of blood pressure via its antagonizing effect to vasopressin. 相似文献
26.
H Koyama T Maruta T Kudo H Mayahara K Yoshida 《Journal of Medical Imaging and Radiation Oncology》2005,49(6):493-496
We present a case in which multiple pancreatic tumours were diagnosed as metastatic clear cell renal carcinomas with chemical shift MRI (CSI) before surgery. Radiologists may be unable to recognize the loss of intensity on CSI macroscopically. We believe that it is useful to make subtraction images and calculate signal intensity on CSI, even if the lesions are multiple metastatic tumours. 相似文献
27.
H Sasano Y Saito H Nagura R Kudo M Rojas S G Silverberg 《International journal of gynecological pathology》1991,10(3):252-259
The lectin-binding properties of 44 cases of serous and mucinous ovarian cystadenoma, tumor of low malignant potential (LMP), and invasive carcinoma were examined histochemically. Wheat germ agglutinin (WGA), concanavalin A (con A), Ulex europaeus agglutinin I (UEA-I), peanut agglutinin (PNA), Ricinus communis agglutinin I (RCA-I), soybean agglutinin (SBA), and Robina pseudoaccacia (RPA) were employed. All the lectins examined were bound to neoplastic epithelial cells of benign and malignant tumors, but none bound exclusively to ovarian tumor cells. Different lectin-binding patterns between serous and mucinous neoplasms were observed, with the exception of RPA. UEA-I, con A, RPA, and PNA in serous neoplasms and UEA-I, RPA, and WGA in mucinous neoplasms demonstrated lectin-binding properties of LMP tumors intermediate between those of cystadenoma and invasive carcinoma. These findings indicate that serous and mucinous ovarian neoplasms contain different glycoconjugates, that malignant transformation of the neoplasms is associated with alteration of these glycoconjugates, and especially that LMP tumors have a different composition of cellular glycoconjugates from that of invasive ovarian carcinoma. 相似文献
28.
Shin-ichiro Maruya Hidekachi Kurotaki Ryuichi Wada Takashi Saku Hideichi Shinkawa Soroku Yagihashi 《Modern pathology》2004,17(6):637-645
Adenoid cystic carcinoma, a relatively uncommon tumor of salivary glands, is characterized by a prolonged clinical course and a fatal outcome. The molecular events underlying their progression are unknown. In this study, we examined the methylation status of E-cadherin gene and its protein expression in 23 cases of adenoid cystic carcinoma and correlated the results with the clinicopathologic factors to determine its role in these tumors. We also analyzed the effect of 5-azacytidine on the re-expression in a methylated cell line of adenoid cystic carcinoma for this gene. In our study, E-cadherin immunoreactivity, although heterogeneous, showed a progressive reduction with high histological grade and in metastatic and recurrent lesions. Promoter methylation was detected in 16 of 23 cases (70%), but there was no correlation with the histological grade or patient prognosis. Microdissection of immuno-negative cells in heterogeneous tumors showed positive methlyation. In the cell line from salivary adenoid cystic carcinoma with methylated E-cadherin, 5-azacytidine restored the E-cadherin expression. Our results indicate that: (1) E-cadherin gene promoter is frequently methylated in adenoid cystic carcinoma, leading to reduced E-cadherin expression, (2) variable E-cadherin expression might result from the intratumoral heterogeneity, and (3) increased extent of methylated areas may be associated with progression and advancement of the disease. 相似文献
29.
Hiroki Sakamoto Masayuki Kitano Takeshi Nishio Yoshifumi Takeyama Chikao Yasuda Masatoshi Kudo 《Digestive endoscopy》2006,18(3):206-211
Endosonography‐guided celiac plexus neurolysis (EUS‐CPN) safely and effectively relieves pain associated with intra‐abdominal malignancies when the neurolytic is accurately injected. We applied contrast medium to evaluate the ethanol injection sites in patients who received EUS‐CPN due to abdominal pain caused by malignancies. We injected, under the guidance of endoscopic ultrasonography (EUS), ethanol containing 10% contrast medium into the celiac plexus of patients with intra‐abdominal pain due to malignancies. Immediately after the endoscopic therapy, patients underwent computed tomography (CT) to confirm the injection site. Images of distribution of injected solutions were classified into three groups. Injected solution dispersed in unilateral and bilateral anterocrural space was defined as ‘unilateral injection’ or ‘bilateral injection’, respectively. Injected solution located out of the anterocrural space was defined as ‘inappropriate injection’. Pre‐ and postprocedure pain was assessed using a standard analog scale. Before and 2, 4, 8, 12, and 16 weeks after the procedure, pain scores were evaluated. From April 2003 to May 2005, 13 patients were enrolled in this study. Improvement of pain score in the ‘bilateral injection’ and ‘unilateral injection’ groups was significantly superior to the change in the ‘inappropriate injection’ group. Although EUS‐CPN was effective in eight of 13 patients (61.5%), additional EUS‐CPN to the ‘inappropriate injection group’ increased the response rate to 84.6%. Injection of ethanol to the anterocrural space by EUS‐CPN produced adequate pain relief. Immediate examination by CT for confirmation of injection sites after EUS‐CPN would increase the likelihood of induction of pain relief. 相似文献
30.
Dr. Shosaku Nakahara M.D. Hideaki Itoh M.D. Ryuichi Mibu M.D. Shinichi Ikeda M.D. Yoshihiro Oohata M.D. Kamesaburo Kitano M.D. Yoshihiko Nakamura M.D. 《Diseases of the colon and rectum》1988,31(10):762-766
Anorectal function was evaluated in eight patients who had low anterior resection of the rectum with a low anastomotic line,
using an EEA™ stapler, with determination of function based on periodic manometric studies and clinical symptoms. Immediately following
surgery all patients suffered from frequent bowel actions and soiling. These symptoms improved with time and most patients
could enjoy almost normal daily life by the sixth postoperative month. One month after surgery, anal canal resting pressure
and maximum squeeze pressure were significantly reduced and rectoanal inhibitory reflex was absent; neither showed a distinct
tendency to improve thereafter. Rectal sensation and reservoir capacity, which also were seriously impaired, recovered satisfactorily
by the time of the six-month examination. This suggests that an improvement of clinical symptoms following this operation
is dependent upon the recovery of reservoir capacity and sensation of the neorectum, and that this operative procedure is
a functionally acceptable option for low rectal cancer. 相似文献