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1.
The effect of (+)-5-oxo-D-prolinepiperidinamide monohydrate (NS-105), a novel cognition enhancer, on adenylate cyclase activity was investigated in cultured neurons of the mouse cerebral cortex. NS-105 (10–7 and 10–6 M) inhibited forskolin-stimulated cyclic AMP formation, an action that was dependent on pertussis toxin-sensitive G proteins. Conversely, in pertussis toxin-pretreated neurons, NS-105 (10–7 –10–5 M) significantly enhanced the forskolin-stimulated cyclic AMP formation, and this action was completely reversed by cholera toxin. A metabotropic glutamate receptor agonist (1S, 3R)-1-aminocyclopentane-1, 3-dicarboxylic acid (1S, 3R-ACPD) produced similar bi-directional actions on the cyclic AMP formation. Both of these inhibitory and facilitatory actions of NS-105 and 1S, 3R-ACPD were blocked by L(+)-2-amino-3-phosphopropinoic acid (L-AP3). NS-105 (10–6 M) and 1S, 3R-ACPD (10–4 M) significantly enhanced isoproterenol- and adenosine-stimulated cyclic AMP formation. The enhancement of such Gs-coupled receptor agonists-stimulated cyclic AMP formation was also produced by quisqualate but not by L(+)-2-amino-4-phosphonobutanoate (L-AP4). The phosphoinositides hydrolysis was enhanced by 1S, 3R-ACPD (10–4 M) but not by NS-105 (10–6 M), however, 1S, 3R-ACPD-induced increase in phosphoinositides turnover was attenuated by NS-105. These findings suggest that NS-105 stimulates metabotropic glutamate receptor subclasses that are coupled both negatively and positively to adenylate cyclase, but it acts as an antagonist at the receptor subclasses that are linked to phosphoinositides hydrolysis. Received: 3 February 1997 / Accepted: 25 April 1997  相似文献   
2.
The greater potency of morphine-6-glucuronide (M6G) as well as the inactivity of morphine-3-glucuronide (M3G) with respect to the antinociceptive effects of the parent molecule, morphine (MOR), have been well established. It has been suggested that M3G is an antagonist of MOR's antinociceptive and respiratory depressive effects. The present study addressed the central nervous system (CNS) interaction of these opiate metabolites on their metabolic and hormonal effects. Whole body glucose kinetics were assessed on conscious, chronically catheterized, unrestrained rats. M3G (5 μg) or H2O (5 μl) was injected intracerebroventricularly (i.c.v.) 15 min prior to the bolus administration of H2O (5 μl), M6G (1 μg), or MOR (80 μg). i.c.v. M3G (5 μg) resulted in behavioral excitation, hyperglycemia (+50%), stimulation of glucose rate of appearance (Ra; +100%), glucose rate of disappeaance (Rd; +70%), and metabolic clearance rate (MCR; +33%) within 30 min after injection with no alterations in hormone concentrations. i.c.v. M6G and MOR produced progressive hyperglycemia with significantly high catecholamine and corticosterone levels. M3G pretreatment resulted in enhanced elevations in plasma glucose levels (+52% and +18%), plasma lactate (+138% and +108%), norepinephrine (+96% and +30%), and epinephrine (+62% and +67%) in response to both i.c.v. MOR and M6G administration. These findings suggest a non-opiate and non-hormonal mechanism for M3G-induced hyperglycemia. In contrast, the metabolic and hormonal responses to i.c.v. M6G and MOR are associated with elevations in catecholamine and corticosterone levels, which are remarkably enhanced by M3G pretreatment, most likely through accelerated catecholamine release. Our findings suggest a modulatory role for MOR glucuronidation, not only by rendering it inactive, as in the case of M3G, but by an interplay of the metabolic effects of the parent molecule and its metabolite  相似文献   
3.
Microinvasive ductal carcinoma of the breast, namely ductal carcinoma in situ with microinvasion (T1mic) as defined by the American Joint Committee on Cancer (AJCC) Staging Manual, is a rare disease, although it is increasing because of widespread use of mammography. The aim of the present study was to describe the clinicopathological and immunohistochemical features of this entity. Twenty-eight patients who were diagnosed as T1mic from January 1997 to August 2002 were studied by using 3-5 mm-thick serial sections with hematoxylin-eosin staining. Immunohistochemical staining for the estrogen receptor (ER), progesterone receptor (PR), p53, Ki-67, and HER-2 were performed. All 28 patients were female, with a mean age of 48.8 years. Twenty-six patients (93%) revealed mammographic abnormalities on routine examination. All foci of the invasions were measured using an ocular micrometer. Invasive foci consisted of isolated cells or cell clusters, or appeared as a tongue-like projection of tumor through the basement membrane of the duct of ductal carcinoma in situ (DCIS). The mean number of invasive foci was 3, and the mean size was 0.6 mm. We found that high nuclear grade and predominant comedo subtype of DCIS components were 57.1% and 46.4%, respectively. Twenty-four cases (86%) demonstrated necrosis of DCIS components. Microinvasion was often associated with periductal stromal reaction (71.5%) and/or a lymphocytic infiltration (78.6%). All patients, excluding two, received axillary resection (the mean number of lymph nodes examined per case was 12), and none had lymph node metastasis. The positive expression of ER and PR strongly related to low grade nuclei and non-comedo subtype; however, the positive expression of HER-2 and P53 related to high grade nuclei and comedo subtype (P<0.01). Ki-67 expression was significantly higher in the high grade nuclei group than in the low grade group (P<0.01). Our study suggested that high nuclear grade and comedo DCIS were more aggressive and more common with microinvasion, and that microinvasion is more likely to be multifocal.  相似文献   
4.
5.
To investigate the adequate extent of esophagectomy and lymphadenectomy for an esophageal cancer localized at the cervicothoracic junction, the mortality and morbidity rates, survival rates, and patterns of recurrence were retrospectively analyzed in two groups—14 patients who underwent total esophagectomy with or without laryngectomy and 15 patients who underwent proximal esophagectomy with or without laryngectomy—at Kurume University Hospital from 1981 to 1996. Proximal esophagectomy with or without laryngectomy resulted in a lower hospital mortality rate and better overall survival for patients who underwent curative esophagectomy compared with total esophagectomy with or without laryngectomy. Multivariate analysis indicated that the extent of esophagectomy (total esophagectomy versus proximal esophagectomy) was not a prognostic factor. The incidence of recurrence was not different between the two groups. Lymph node metastasis or recurrence from such esophageal cancers was localized to the neck and upper mediastinum. For an esophageal cancer localized at the cervicothoracic junction, therefore, proximal esophagectomy with or without laryngectomy and with cervical and upper mediastinal lymphadenectomy could be better indicated for preselected patients.  相似文献   
6.
We aimed to evaluate the utility of a simplified ultrasonography (US) scoring system, which is desired in daily clinical practice, among patients with rheumatoid arthritis (RA) receiving biological/targeted synthetic disease-modifying antirheumatic drugs (DMARDs).A total of 289 Japanese patients with RA who were started on tumor necrosis factor inhibitors, abatacept, tocilizumab, or Janus kinase inhibitors between June 2013 and April 2019 at one of the 15 participating rheumatology centers were reviewed. We performed US assessment of articular synovia over 22 joints among bilateral wrist and finger joints, and the 22-joint (22j)-GS and 22-joint (22j)-PD scores were evaluated as an indicator of US activity using the sum of the GS and PD scores, respectively.The top 6 most affected joints included the bilateral wrist and second/third metacarpophalangeal joints. Therefore, 6-joint (6j)-GS and -PD scores were defined as the sum of the GS and PD scores from the 6 synovial sites over the aforementioned 6 joints, respectively. Although the 22j- or 6j-US scores were significantly correlated with DAS28-ESR or -CRP scores, the correlations were weak. Conversely, 6j-US scores were significantly and strongly correlated with 22j-US scores not only at baseline but also after therapy initiation.Using a multicenter cohort data, our results indicated that a simplified US scoring system could be adequately tolerated during any disease course among patients with RA receiving biological/targeted synthetic DMARDs.  相似文献   
7.
PURPOSE: We retrospectively analyzed prognostic factors for surgical resection and intraoperative radiation therapy to identify indicators for this treatment strategy. METHODS: Thirty-nine consecutive patients with locally recurrent colorectal cancer who underwent surgical resection with intraoperative radiation therapy from January 1, 1987, to June 30, 1999, were analyzed. The mean electron energy was 10.5 MeV and the mean intraoperative radiation dose was 22.6 Gy. Kaplan-Meier survival estimates were obtained for the 37 patients who recovered postoperatively. Prognostic factors were analyzed univariately by log-rank test and multivariately by Coxs proportional hazards model. RESULTS: Three-year cumulative survival was 44 percent (standard error = 11) for 26 patients free of unresectable distant metastasis who underwent surgical resection and intraoperative radiation therapy for pelvic recurrence of colorectal cancer, but none of the 11 patients with unresectable distant metastasis survived 3 years. Preoperative prognostic factors which were significant on univariate and multivariate analysis were unresectable distant metastasis (P = 0.001) and elevated preoperative serum CA 19–9 (P = 0.02). Patients with synchronous resection of local recurrence and distant metastasis had a significant survival advantage over those without resection of metastases (P = 0.02). Univariate analysis in a subgroup of 26 patients without unresectable distant metastasis revealed pain (P = 0.0003) to be a useful preoperative prognostic indicator, whereas tumor fixation (P = 0.01) and amount of residual tumor after surgical resection (P = 0.01) were significant intraoperative and postoperative factors, respectively. Fluorouracil-based postoperative systemic chemotherapy produced a significant survival benefit (P = 0.04). CONCLUSIONS: Patients with unresectable distant metastasis are not suitable candidates for surgical resection and intraoperative radiation therapy, whereas those with resectable metastasis are potential candidates. Intraoperative radiation therapy may be less useful for patients with pain, elevated preoperative CA19–9, fixed tumors, or gross residual tumor after surgical resection. Multimodal treatment strategies combining preoperative and/or postoperative external beam radiation therapy and intraoperative radiation therapy with fluorouracil-based systemic chemotherapy are recommended for patients with these indicators.  相似文献   
8.
PURPOSE Approximately 50 percent of all patients with resected colorectal carcinoma have tumors with pT3 status; however, no subclassifications of the penetration depth have been proposed. The purpose of this study is to evaluate the significance of histologic invasion beyond subserosal elastic lamina by colorectal carcinoma for postoperative recurrence and long-term survival after resection.METHODS pT3 colorectal carcinomas located above the peritoneal reflection were retrospectively classified into two depth grades (subserosal elastic lamina classification). Namely, pT3-shallow is defined as tumors those are confined above the subserosal elastic lamina, and pT3-deep is defined as tumors those penetrate beyond it. Based on subserosal elastic lamina classification, the 325 consecutive patients who underwent resections were divided into two groups, and then the clinicopathologic features, incidence of postoperative recurrence, and survival rates were compared between the two groups.RESULTS The overall postoperative recurrence rate in the pT3-deep group (35.2 percent) was higher than that in the pT3-shallow group (20.8 percent). In detail, liver and peritoneal recurrence rates in the pT3-deep group (19.7 percent, 7.7 percent, respectively) were higher than those in the pT3-shallow group (9.4 percent, 2.0 percent, respectively). There was a strong difference (P < 0.0001) in overall survival rate between the pT3-deep group (5-year survival of 57.0 percent) and the pT3-shallow group (5-year survival of 78.6 percent). Multivariate analysis revealed that synchronous hematogenous metastasis (P < 0.0001), lymph node metastasis (P < 0.05), venous invasion (P < 0.01), and subserosal elastic lamina classification (P < 0.05) were the independent prognostic factors for postoperative survival.CONCLUSIONS The newly proposed subserosal elastic lamina classification is a useful subclassification to predict the prognosis of patients with resected pT3 colorectal carcinomas.Presented at the 101st Annual Congress of the Japan Surgical Society, Sendai, Miyagi, Japan, April 11 to 13, 2001.  相似文献   
9.
The skeletal stability of Le Fort I osteotomy was evaluated cephalometrically in 40 consecutive patients with unilateral cleft lip and palate (UCLP) (27 male and 13 female) who were operated on between 1987-1995. Their mean age at the time of operation was 23.7 years (range 16.3-40.4). The onepiece Le Fort I osteotomy was fixed with titanium plates and the osteotomy line was bone-grafted. Neither intermaxillary fixation nor occlusal splints were used postoperatively. Skeletal stability was analysed both horizontally and vertically on cephalograms taken shortly before operation, immediately afterwards, and at six months and at one year postoperatively. The mean maxillary advancement (point A) during the Le Fort I was 3.9 mm (range 0- 8.9) and mean vertical lengthening 4.5 mm (range -0.6-10.5). One year postoperatively the mean maxillary horizontal relapse was 20.5% (0.8 mm, range 0-3.7) whereas the mean vertical relapse was 22.2% (1 mm, range 0-5.7). The vertical relapse reduced from 38% to 8.3% between 1987 and 1995, and there was a positive correlation between the amount of maxillary advancement and relapse both horizontally and vertically.  相似文献   
10.
Oral cenesthopathy is a somatic delusion or hallucination involving the oral area and is categorized as a delusional disorder, somatic type. The pathophysiology of this intractable condition remains obscure. In this study, we clarified the pathophysiology of oral cenesthopathy by evaluating regional brain perfusion. We performed single photon emission computed tomography (SPECT) using 99mTc-ethylcysteinate dimer in 16 subjects (cenesthopathy:control = 8:8). The SPECT images were visually assessed qualitatively, and quantitative analyses were also performed using a three-dimensional stereotactic region-of-interest template. The visual assessment revealed a right > left perfusion asymmetry in broad areas of the brain among the patients. The quantitative analysis confirmed that the regional cerebral blood flow values on the right side were significantly larger than those on the left side for most areas of the brain in the patients. A comparison of the R/(R + L) ratios in both groups confirmed the significant brain perfusion asymmetry between the two sides in the callosomarginal, precentral, and temporal regions in the patients. Qualitative evaluation of the SPECT images revealed right > left brain perfusion asymmetry in broad regions of the brain. Moreover, the quantitative analyses confirmed the perfusion asymmetry between the two sides in the frontal and temporal areas. Those may provide the key for elucidation of the pathophysiology of oral cenesthopathy.  相似文献   
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