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61.
Won JS  Song DK  Huh SO  Kim YH  Suh HW 《Hippocampus》2000,10(3):236-243
The in vivo short-term effect of melatonin on kainic acid (KA)-induced proenkephalin (proENK) or prodynorphin (proDYN) mRNA, and on AP-1 protein levels in the rat hippocampus, were studied. Melatonin (5 mg/kg) or saline was administered intraperitoneally (i.p.) to rats 30 min prior to and immediately after i.p. injection of KA (10 mg/kg). Rats were sacrificed 1 and 3 h after KA injection. The proENK and proDYN mRNA levels were significantly increased 3 h after KA administration. The elevations of both proENK and proDYN mRNA levels induced by KA were significantly inhibited by the preadministration with melatonin. The increases of proENK and proDYN mRNA levels induced by KA were well-correlated with the increases of c-Fos, Fra-2, FosB, c-Jun, and JunB protein levels, which were significantly increased 3 h after KA administration and effectively inhibited by administration with melatonin. In an electrophoretic mobility shift assay, both AP-1 and ENKCRE-2 DNA binding activities were increased by KA, which were also attenuated by the administration of melatonin. In addition, cross-competition studies revealed that AP-1 or ENKCRE-2 DNA binding activity was effectively reduced by the 50x unlabeled cross-competitor. Therefore, these data suggest that melatonin has an inhibitory role in KA-induced gene expression, such as proENK and proDYN mRNA expression, and this may be due to a reduction of KA-induced AP-1 or ENKCRE-2 DNA binding activity.  相似文献   
62.
The effects of intracerebroventricular (i.c.v.) and intrathecal (i.t.) 3-isobutyl-1-methylxanthine (IBMX), cholera toxin (CTX) and pertussis toxin (PTX) administration on immobilization-induced antinociception were studied in ICR mice. Antinociception was assessed by the tail-flick assay. Immobilization of the mouse increased inhibition of the tail-flick response for at least 1 h. The pretreatment with i.t. IBMX (0.01-1 ng), but not i.c.v. IBMX, significantly attenuated immobilization-induced inhibition of the tail-flick response. The pretreatments with i.c.v. PTX (0.05-0.5 microg) as well as i.t. CTX, but neither i.c.v. CTX (0.05-0.5 microg) nor i.t. PTX, potentiated the inhibition of the tail-flick response induced by immobilization stress. Our results suggest that spinally located phosphodiesterase appears to be involved in the production of immobilization stress-induced antinociception. In addition, inactivation of supraspinally located PTX-sensitive G-proteins and spinally located CTX-sensitive G-proteins may modulate immobilization stress-induced antinociception.  相似文献   
63.
The association of hyperglycemia and markers of hepatic dysfunction with dextrose infusion rates in Korean patients receiving total parenteral nutrition (TPN) was studied. A retrospective study of 122 patients with normal glucose levels and liver function tests (LFTs) was conducted. Pharmacy and medical records of all patients who received TPN from three university-affiliated teaching hospitals in Korea between January 1998 and December 1999 were reviewed. Each patient was categorized as receiving dextrose at (1) < or = 5 or > 5 mg/kg/min and (2) < or = 4, 4.1-5, 5.1-6, or > 6 mg/kg/min. Fifty-five patients received dextrose at a rate of > 5 mg/kg/min for 15.1 +/- 12.8 days and 67 patients at a rate of < or = 5 mg/kg/min for 10.1 +/- 6.8 days. Two patients in each group did not have follow-up glucose levels. Of the 53 patients in the > 5 mg/kg/min group, 16 exhibited hyperglycemia, compared with 21 of the 65 receiving lower rates of dextrose infusion. Elevated aspartate transaminase was the most common abnormal LFT value in both groups (25% and 29% in the < or = 5- and > 5-mg/kg/min groups, respectively). In the group receiving dextrose at > 5 mg/kg/min, 22.2% had two hepatic enzyme levels elevated concurrently, while 18.5% had two hepatic enzyme levels elevated in the group receiving dextrose at < or = 5 mg/kg/min. Regression analysis revealed that duration of TPN and dextrose infusion rate were positively correlated with blood glucose levels and that duration of TPN was positively correlated with abnormal LFT values. A retrospective study of Korean patients revealed no significant difference in the risk of hyperglycemia or hepatic dysfunction between those receiving < or = 5 and > 5 mg/kg/min dextrose infusion in their TPN.  相似文献   
64.
Seventy-eight patients (85 affected hips and 71 unaffected hips) with Legg-Calvé-Perthes disease were included in this study to evaluate the metaphyseal change in radiographs and magnetic resonance imaging (MRI) and to define the type of the metaphyseal cyst according to presence or absence of the epiphyseal involvement. The content of the metaphyseal cyst was evaluated by using T1,T2, proton, and gadolinium-enhanced T1-weighted MRI scans. Among 85 hips, there were no changes in 32 hips, marrow edema in 13 hips, false cyst with epiphyseal involvement in 28 hips, and true cyst without epiphyseal involvement in 12 hips. Granulation tissue was found in the false cysts and water-rich fibrotic tissue was found in the true cysts based on the MRI scans. The metaphyseal change in MRI scans was shown in 71% of groups 3 and 4 and in 35% of groups 1 and 2 according to the Catterall classification, and 52% of group A, 56% of group B, and 86% of group C according to the Herring classification. Of the 30 hips at the avascular stage, 33% showed metaphyseal cyst in MRI scans. Of the 53 hips at the fragmentation stage, 60% showed the metaphyseal cyst.  相似文献   
65.
PURPOSE: To evaluate the potential of the new prognostic information gained by analyzing the coexpression of epidermal growth factor receptor (EGFR) and cyclooxygenase-2 (COX-2) in cervical cancer patients. EXPERIMENTAL DESIGN: Sixty-eight patients with International Federation of Gynecology and Obstetrics stage IIB squamous cell carcinoma of the uterine cervix, who underwent concurrent chemoradiotherapy between 1993 and 1996, were divided into the following four groups according to their immunoreactivities for EGFR and COX-2 in paraffin-embedded sections: (a). the EGFR-negative/COX-2-negative group (n = 11); (b). the EGFR-negative/COX-2-positive group (n = 8); (c). the EGFR-positive/COX-2-negative group (n = 27); and (d). the EGFR-positive/COX-2-positive group (n = 22). The clinical features, patterns of treatment failure, and survival data in the four groups were compared. RESULTS: Positive immunoreactivity for EGFR and COX-2 was observed in 49 of 68 (72%) and 19 of 68 (28%), respectively. However, no strong correlation was found between the levels of EGFR and COX-2 immunopositivity (R(2) = 0.05, P = 0.07). Patients in the EGFR-positive/COX-2-positive group had a higher likelihood of locoregional recurrence than those in the other three groups (P = 0.02). Of the patients in the four groups, patients positive for both oncoproteins were found to have the worst prognosis with an overall 5-year disease-free survival rate of 55% compared with 91% for the EGFR-negative/COX-2-negative patients, 88% for the EGFR-negative/COX-2-positive patients, and 69% for the EGFR-positive/COX-2-negative patients (P = 0.05, log-rank test). In addition, the synchronous coexpression of the EGFR and COX-2 oncoproteins was found to be an independent prognostic factor by univariate and multivariate analyses (relative risk = 4.0, P = 0.03). CONCLUSIONS: Given these observations, we conclude that the coexpression of EGFR and COX-2 immunoreactivity may be used as a potent molecular risk factor for predicting the poor survival of patients with the International Federation of Gynecology and Obstetrics stage IIB squamous cell carcinoma of the uterine cervix.  相似文献   
66.
PURPOSE: This phase II, open-label, multicenter study assessed the efficacy and safety of the potential radiation enhancer RSR13 plus cranial radiation therapy (RT) in patients with brain metastases. The primary end point was patient survival in comparison with the Radiation Therapy Oncology Group Recursive Partitioning Analysis Brain Metastases Database (RTOG RPA BMD). PATIENTS AND METHODS: Eligibility criteria were age > or = 18 years, Karnofsky performance score > or = 70, and brain metastases with solid tumor histology. Patients received cranial RT, 30 Gy in 10 fractions of 3 Gy each, preceded by RSR13, 50 to 100 mg/kg intravenously over 30 minutes. Univariate and multivariate comparisons of survival and cause of death were made between class II study patients and RTOG BMD patients. RESULTS: Fifty-seven RPA class II patients were enrolled. With a minimum follow-up of 24 months, the median survival time and 1- and 2-year survival rates were 6.4 months, 23%, and 11% for the RSR13-treated patients compared with 4.1 months, 15%, and 3% for the RTOG BMD patients (P =.0174). In an exact-matched case analysis (n = 38), median survival time for RSR13 patients was 7.3 months versus 3.4 months for the RTOG BMD patients (P =.006). There was a 54% reduction in the risk of death for RSR13 patients (P =.0267). RSR13-related adverse events of greater than or equal to grade 3 toxicity that occurred in more than one patient included hypoxia, headache, anemia, fatigue, hypertension, and intracranial hypertension. CONCLUSION: RSR13 plus cranial RT resulted in a significant improvement in survival, as well as a reduction in death due to brain metastases, compared with class II patients in the RTOG BMD.  相似文献   
67.
PURPOSE: This phase III randomized trial evaluated survival as well as neurologic and neurocognitive function in patients with brain metastases from solid tumors receiving whole-brain radiation therapy (WBRT) with or without motexafin gadolinium (MGd). PATIENTS AND METHODS: Patients were randomly assigned to 30 Gy of WBRT +/- 5 mg/kg/d MGd. Survival and time to neurologic progression determined by a blinded events review committee (ERC) were coprimary end points. Standardized investigator neurologic assessment and neurocognitive testing were evaluated. RESULTS: Four hundred one (251 non-small-cell lung cancer) patients were enrolled. There was no significant difference by treatment arm in survival (median, 5.2 months for MGd v 4.9 months for WBRT; P =.48) or time to neurologic progression (median, 9.5 months for MGd v 8.3 months for WBRT; P =.95). Treatment with MGd improved time to neurologic progression in patients with lung cancer (median, not reached for MGd v 7.4 months for WBRT; P =.048, unadjusted). By investigator, MGd improved time to neurologic progression in all patients (median, 4.3 months for MGd v 3.8 months for WBRT; P =.018) and in lung cancer patients (median, 5.5 months for MGd v 3.7 months for WBRT; P =.025). MGd improved neurocognitive function in lung cancer patients. CONCLUSION: The overall results did not demonstrate significant differences by treatment arm for survival and ERC time to neurologic progression. Investigator neurologic assessments demonstrated an MGd treatment benefit in all patients. In lung cancer patients, ERC- and investigator-determined time to neurologic progression demonstrated an MGd treatment benefit. MGd may improve time to neurologic and neurocognitive progression in lung cancer.  相似文献   
68.
Background.The diagnosis of both low (LSIL) and high (HSIL) grade squamous intraepithelial lesions in the same cervical specimen may reflect classification variation, morphologic progressionin situ,and, conceivably, different HPV infections. We addressed these possibilities in cervical specimens previously diagnosed as containing both LSIL (condyloma/CIN1) and HSIL (CIN2/3).Methods.All cases with a histologic diagnosis of LSIL and HSIL from 1994–1996 were reviewed. On review, lesions were scored as (1) no significant variation in lesion grade (classification discrepancies) and showing a (2) one (CIN1–2) or (3) two (CIN1–3) grade shift in the same case. In cases in which a one or two grade shift was confirmed, low (CIN1) and high (CIN2–3) grade foci were microdissected and extracted DNA analyzed for HPV by PCR and RFLP analysis.Results.Of 98 cases available for review, 58 (59%) did not exhibit significant variation in grade (classification discrepancy), and 40 (41%) showed a one (25) or two (15) grade shift. Of the latter group both LSIL and HSIL foci were HPV(+) in 26 (65.0%). The same HPV was present in both LSIL and HSIL foci in 15/15 lesions with a one grade shift (CIN1–2). In contrast, a significantly higher proportion of lesions with a two grade shift (CIN1–3) contained two different HPV types (4/11 vs 0/15;P= 0.01). Combinations of HPVs in the low/high grade foci, respectively, included HPV 11/16 (1), 11/16 + 18 (1), and HPV39/16 (2).Conclusions.Lesions containing LSIL and HSIL which span two grades (CIN1 and CIN2) most likely represent morphologic progression in a single infection. Lesions containing CIN1 and CIN 3 may be attributed to both lesion progression and two coincident infections; the latter sometimes present in the same histologic section. The latter phenomenon has implications for both the diagnosis of CIN and interpretation of “morphologic progression” from very low to high grade in the same case.  相似文献   
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