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1.
Mitogen-activated protein kinase (MAPK) is a serine-threonine kinase that is activated by various extracellular stimuli. Extracellular signal-regulated kinases (ERK1 and ERK2), an MAPK subfamily, are activated by many oncogenes, such as ras and raf, and they induce cell proliferation. myc is also an oncogene and one of the targets of ERKs. Mutations of ras and overexpression of myc were found in various human cancers, and ERKs were also reported to play a role in carcinogenesis. In this study, we examined 39 biopsy specimens of oral squamous cell carcinoma (OSCC) and 5 of normal gingival mucosa for the expression of ERK protein and the proliferation marker, MIB-1 (Ki-67 antibody). Thirteen OSCC specimens and five normal gingival biopsies were also examined for the expression of ERKs mRNA by in situ hybridization. Double staining for ERKs and MIB-1 was also performed. Histologically, 18 patients (46%) were diagnosed with well-differentiated SCC, 17 (44%) with moderately differentiated SCC, and 4 (10%) with poorly differentiated SCC. The histologic grade correlated with the MIB-1 index. The localization of ERK1 was similar to that of ERK2. Positive signals for ERK proteins were localized in superficial keratinocytes in normal gingival mucosa, whereas these mRNAs were weakly positive in the basal and spinous layer. Basal and suprabasal cells were positive for MIB-1. In well-differentiated and moderately differentiated OSCC, positive signals for ERK mRNA and proteins were found at higher levels than in normal gingival mucosa in keratotic cells around cancer pearls. Some cells showed positive signals for ERKs and MIB-1. Furthermore, most cancer cells in poorly differentiated SCC were positive for both ERK and MIB-1. The histologic grade was statistically related to the percentage of cells positive for both ERK and MIB-1. This suggested that ERKs might be related to proliferation in OSCC.  相似文献   

2.
OBJECTIVES: This study was designed to evaluate the effect of carvedilol on nitrate tolerance in patients with chronic heart failure. BACKGROUND: The attenuation of cyclic guanosine 5'-monophosphate (cGMP) production due to inactivation of guanylate cyclase by increased superoxide has been reported as a mechanism of nitrate tolerance. Carvedilol has been known to combine alpha/beta-blockade with antioxidant properties. METHODS: To evaluate the effect of carvedilol on nitrate tolerance, 40 patients with chronic heart failure were randomized to four groups that received either carvedilol (2.5 mg once a day [carvedilol group, n=10]), metoprolol (30 mg once a day [metoprolol group, n=10]), doxazosin (0.5 mg once a day [doxazosin group, n=10]) or placebo (placebo group, n=10). Vasodilatory response to nitroglycerin (NTG) was assessed with forearm plethysmography by measuring the change in forearm blood flow (FBF) before and 5 min after sublingual administration of 0.3 mg NTG, and at the same time blood samples were taken from veins on the opposite side to measure platelet cGMP. Plethysmography and blood sampling were obtained serially at baseline (day 0); 3 days after carvedilol, metoprolol, doxazosin or placebo administration (day 3); and 3 days after application of a 10-mg/24-h NTG tape concomitantly with carvedilol, metoprolol, doxazosin or placebo (day 6). RESULTS: There was no significant difference in the response of FBF (%FBF) and cGMP (%cGMP) to sublingual NTG on day 0 and day 3 among the four groups. On day 6, %FBF and %cGMP were significantly lower in the metoprolol, doxazosin and placebo groups than on day 0 and day 3, but these parameters in the carvedilol group were maintained. CONCLUSIONS: These results indicated that carvedilol may prevent nitrate tolerance in patients with chronic heart failure during continuous therapy with NTG.  相似文献   

3.
In LLC-PK1 kidney epithelial cells, a 5-h pretreatment with glyceryl trinitrate (GTN) resulted in substantial desensitization of the intracellular cyclic GMP response to a subsequent 10-min challenge with GTN (1 microM). GTN-tolerant cells were fully sensitive to the spontaneous nitric oxide (NO) donor spermine NONOate, which does not require enzymatic bioactivation. Cyclic GMP stimulation by GTN was up to 3.1-fold higher when vitamin C (1-10 mM) was present during the pretreatment period. In contrast, other oxygen radical scavengers such as tiron or dimethylsulfoxide and the NO scavenger PTIO left tolerance induction unaltered. Together, our results suggest that reactive oxygen species or NO do not contribute to the development of nitrate tolerance. Tolerance reduction by vitamin C may be due to a stabilizing effect on enzymes involved in the bioconversion of GTN to NO.  相似文献   

4.
5.
OBJECTIVE: To investigate the long-term effects of raloxifene on fasting plasma homocysteine levels in postmenopausal women compared with conjugated equine estrogen (CEE). DESIGN: Randomized, double-blind, placebo-controlled study. SETTING: Outpatient department of a university hospital. PATIENT(S): Fifty-two hysterectomized, healthy postmenopausal women. INTERVENTION(S): Oral raloxifene in two dosages (60 mg/d [n=13] and 150 mg/d [n=13]), oral CEE (0.625 mg/d [n=13], and placebo (n=13) were given for 24 months. MAIN OUTCOME MEASURE(S): Fasting plasma homocysteine concentrations. RESULT(S): Plasma homocysteine levels were not altered in the placebo group. After 12 months, a significant reduction versus baseline in the mean plasma homocysteine level (-16%) was found only in the raloxifene 150-mg group. The mean change in plasma homocysteine levels within this group also was significantly different from the changes versus baseline found in the placebo group (+2%) and the raloxifene 60-mg group (-2%), but not different from those found in the CEE group (-8%). After 24 months, plasma homocysteine levels were decreased significantly in the raloxifene 150-mg and CEE groups compared with both baseline (-13% and -10%, respectively) and placebo values (-15% and -11%, respectively). No significant change in plasma homocysteine levels was observed in the raloxifene 60-mg group. CONCLUSION(S): Raloxifene has a favorable, dose-related effect on plasma homocysteine levels in postmenopausal women.  相似文献   

6.
7.
Adherence with inhaled beta-agonists and corticosteroids in 24 asthmatic children was tracked over 3 months utilizing the metered-dose inhaler chronolog (MDIC). Patients seldom took all of their medications as prescribed, and failed to take any inhaled corticosteroid doses on a median of 41.8% of days or inhaled beta-agonists on 28.1% of days despite prescribed daily use. Medication nonadherence was correlated with lower levels of asthma knowledge (Asthma Knowledge Questionnaire) and family dysfunction (Family Assessment Device), but not child behavior disorder (Child Behavior Checklist). Patients tended to dramatically over-report medication use. Improved identification of the markers of nonadherence can directly facilitate more efficient targeting of behavioral interventions, resulting in improved adherence, better illness control, and less requirement of urgent medication intervention.  相似文献   

8.
The migraine prophylactic effect of 10 mmol magnesium twice-daily has been evaluated in a multicentre, prospective, randomized, double-blind, placebo-controlled study. Patients with two to six migraine attacks per month without aura, and history of migraine of at least 2 years, were included. A 4-week baseline period without medication was followed by 12 weeks of treatment with magnesium or placebo. The primary efficacy end-point was a reduction of at least 50% in intensity or duration of migraine attacks in hours at the end of the 12 weeks of treatment compared to baseline. With a calculated total sample size of 150 patients, an interim analysis was planned after completing treatment of at least 60 patients, which in fact was performed with 69 patients (64F, 5M), aged 18-64 years. Of these, 35 had received magnesium and 34 placebo. The number of responders was 10 in each group (28.6% under magnesium and 29.4% under placebo). As determined in the study protocol, this was a major reason to discontinue the trial. With regard to the number of migraine days or migraine attacks there was no benefit with magnesium compared to placebo. There were no centre-specific differences, and the final assessments of treatment efficacy by the doctor and patient were largely equivocal. With respect to tolerability and safety, 45.7% of patients in the magnesium group reported primarily mild adverse events like soft stool and diarrhoea in contrast to 23.5% in the placebo group.  相似文献   

9.
10.
In 1994, a Ph.D.-study started regarding pharmacy, organization and management (APOM) in the Netherlands. The APOM-project deals with the structuring and steering of pharmacy organization. This article describes a summary of the theoretical background of the project and the empirical results of a pilot study (n = 24). No generalization to the population of pharmacies in the Netherlands was made. Three mixes of objectives in pharmacy organization were theoretically postulated; the product mix, the process mix, and the customer mix. Mainly, the purpose of the pilot study was method selection. Additionally, it was studied if thought and action of pharmacy managers corresponded, and, if theoretical pharmacy mixes corresponded with the empirical pharmacy mixes. Two methods were selected to be applied in a survey. Thought and action did not correspond for most pharmacy managers. Thought related to customer and product mainly, and action related to process and customer mainly.  相似文献   

11.
The hypothesis was tested that 7-sulfooxymethylbenz[a]anthracene (7-SBA) is an ultimate electrophilic and carcinogenic form of 7-hydroxymethylbenz[a]anthracene. In conformity with this hypothesis, 7-SBA was more carcinogenic than 7-HBA in inducing sarcomas at the site of repeated subcutaneous injection. These metabolites were individually administered to female Sprague-Dawley rats, beginning at 30 days of age, in 0.2 mumol doses given three times each week for 20 doses. One year after the first injection of 7-SBA, seven of thirteen female Sprague-Dawley rats had developed sarcomas. 7-HBA, on the other hand, had induced sarcomas at the site of injection in only two of tweleve rats. No tumors developed either in the control group given sesame oil:DMSO only or in the untreated control group. It would appear from the results summarized here that the search for an ultimate electrophilic and carcinogenic form of 7-HBA has been successful.  相似文献   

12.
Although several studies on tuberculous (TB) pleurisy suggest that the addition of corticosteroids to anti-TB therapy may have beneficial effects, these agents are not used routinely. To assess the effects of short-term oral prednisone therapy in TB pleurisy, 74 patients were randomly assigned in a double-blind fashion to treatment with either placebo or prednisone at a dose of 0.75 mg/kg/d for up to 4 weeks with gradual reduction over an additional 2 weeks. All subjects received a standard 3-drug anti-TB chemotherapy regimen for 6 months. TB pleurisy was diagnosed by histologic study and/or culture of pleural biopsy specimens obtained at thoracoscopy. Complete drainage of the effusion was performed simultaneously. Outcome measures were assessed periodically for 24 weeks, including indexes of morbidity and pleural thickening. After randomization, four patients were excluded from the final analysis. Of the 70 patients analyzed, 34 received prednisone and 36 received placebo. Demographic and clinical characteristics of the treatment groups were comparable at the time of hospital admission. Although a statistically significant improvement in symptoms occurred earlier in the prednisone group (8 weeks) than in the placebo group (12 weeks), between-group comparison showed no significant differences at any of the follow-up evaluations. The proportion of subjects in the prednisone group (53.1%) with residual pleural thickening at 6 months did not differ significantly from that of the placebo group (60%). Pleural effusions did not recur in any of the patients. Initial complete drainage of the effusion was associated with greater symptomatic improvement than any subsequent therapy. We conclude that standard anti-TB therapy and early complete drainage is adequate for the treatment of TB pleurisy. The addition of short-term oral prednisone therapy neither results in clinically relevant earlier symptom relief nor confers a beneficial effect on residual pleural thickening.  相似文献   

13.
BACKGROUND: Nicotine replacement therapies have proved to be of value in smoking cessation. However, not all smokers can use the nicotine gum or nicotine patch owing to side effects. In addition, the absorption of nicotine from these formulas is slow compared with smoking. A nicotine nasal spray delivers nicotine more rapidly. The objective of this study was to evaluate the efficacy and safety of the nicotine nasal spray for smoking cessation. METHODS: Subjects were recruited through advertisements in newspapers and among patients referred to the smoking cessation clinic at Sahlgren's Hospital, G?teborg, Sweden. Two hundred forty-eight smokers were treated in small groups with eight counseling sessions over 6 weeks. At their first group session, subjects were randomized to a group receiving nicotine spray (n = 125), 0.5 mg of nicotine per single spray, or to a placebo group (n = 123). The procedure was double blind. Success rates were measured up to 12 months. The nonsmoking status was verified by expired carbon monoxide less than 10 ppm. RESULTS: Significantly more subjects in the nicotine group were continuously abstinent for 12 months than in the placebo group (27% vs 15%; odds ratio, 2.16; 95% confidence interval, 1.15 to 4.12). Ten of the 34 abstinent subjects in the nicotine group used the spray for 1 year. Mild or moderate side effects were rather frequent for both sprays, but they were significantly more for the nicotine spray. Subjects with high scores (> 7) on Fagerstr?m's tolerance questionnaire had a significantly lower success rate with placebo than with the nicotine spray. For subjects with low scores, there was no difference. CONCLUSION: Nicotine nasal spray in combination with group treatment is an effective aid to smoking cessation.  相似文献   

14.
BACKGROUND: Leishmaniasis recidiva cutis (LRC) is rare in New World leishmaniasis. Only seven cases have been reported so far. MATERIALS AND METHODS: Four cases are reported here. Parasite diagnosis was performed by classical methods of touch preparations, histopathologic sections, and cultures. In addition, the detection of parasite DNA by the polymerase chain reaction (PCR) was performed in all cases. RESULTS: Parasites were detected by at least one of the classical methods in all primary lesions; however, only the PCR was positive in the recidivant lesions. DISCUSSION: LRC cases most likely represent a reactivation of an initial infection, probably due to the persistence of parasites in scarred tissue. Although lupoid leishmaniasis (LL) has been used as a synonym of LRC, a clear difference between LRC and LL can be defined as LL is the initial clinical presentation while LRC is a recurrent lesion. CONCLUSIONS: The results indicate that it is not appropriate to use these two denominations as synonyms. The designation of LRC should be maintained in order to define recidives occurring at the border of an old scar of cutaneous leishmaniasis, avoiding the confusion with the lupoid form of the disease.  相似文献   

15.
The nootropic agent piracetam has been shown to improve learning and memory, and it may, by this means, facilitate recovery and rehabilitation after a stroke. We report the results of a pilot study exploring its effects in patients undergoing rehabilitation after acute cerebral infarction in the carotid artery territory. We compared piracetam and placebo, each given for 12 weeks, in a multicenter, double-blind, randomized trial of parallel-group design; testing was performed at baseline (6-9 weeks poststroke), weeks 5 and 12, and, in fewer patients, 12 weeks after termination of treatment. Standardized tests of activities of daily living (Barthel Index, Kuriansky Test), aphasia (Aachen Aphasia Test), and perception (Rivermead Perception Assessment Battery) were the primary efficacy variables. Of 158 patients, 137 (81 males, 56 females) were studied after treatment and 88 at 24-week follow-up. Thirty patients on piracetam (45%) and 37 on placebo (53%) were aphasic on entry. Both groups, including the subgroups with aphasia, were well matched at baseline for demographic data, stroke sequelae, type and severity of aphasia, and prognostic parameters. Multivariate analysis of Aachen Aphasia subtest scores showed a significant overall improvement relative to baseline in favor of piracetam (p = 0.02) at 12 weeks. This was not seen at 24 weeks when, however, fewer patients were available for evaluation so that we could neither confirm nor deny whether improvement was maintained after cessation of piracetam. We were unable to demonstrate an effect on tests of activities of daily living and could neither confirm nor exclude an effect on perceptual deficit. We have shown an improvement in aphasia in patients undergoing rehabilitation after a stroke after 12 weeks' treatment with piracetam that requires confirmation in further studies.  相似文献   

16.
A randomized double-blind, placebo-controlled study was performed to determine the safety, efficacy, and effect of thalidomide on a variety of immunological and biochemical parameters in asymptomatic human immunodeficiency virus (HIV)-positive patients. Nineteen male patients with elevated markers of immune activation and CD4 cell counts above 400/mm3 were randomized to either placebo or thalidomide at 100 mg/day for 24 weeks. However, only 3 (of 10) patients receiving thalidomide completed all 24 weeks compared to 6 (of 9) patients receiving placebo. This was mainly due to fatigue (somnolence is a recognized side effect), although this was also seen to a lesser extent in the placebo group and so may not be drug attributable. No significant changes in CD4/CD8 count, activation markers, TNF-alpha, or TNFR1 were observed. However, a nonsignificant trend toward inhibition of mitogen-induced TNF-alpha production was observed in the thalidomide arm. The lack of systemic effect and the lower tolerance of thalidomide (at this dose) in asymptomatic patients highlights the need for pharmacokinetic analysis to address possible absorption problems and the need for more potent and less toxic TNF-alpha inhibitors to be developed for use in this type of study.  相似文献   

17.
Adrenomedullin is a potent vasodilator peptide that was isolated from pheochromocytoma. Localization of adrenomedullin-like immunoreactivity was studied by immunocytochemistry in the human hypothalamus and adrenal gland. Adrenomedullin-immunoreactive cell bodies were found in the paraventricular, supraoptic and infundibular nuclei of the hypothalamus. Both magnocellular and parvocellular cells of the paraventricular nucleus were positively immunostained. Adrenomedullin-like immunoreactivity was localized in the adrenal medulla. No positive immunostaining was observed in the vascular endothelium, vascular smooth muscle cell or adrenal cortex. The preabsorption of the antiserum with synthetic human adrenomedullin (1-52) abolished the immunostaining. These findings indicate that adrenomedullin-like immunoreactivity is localized in the paraventricular, supraoptic and infundibular nuclei as well as in the adrenal medulla, and suggest that adrenomedullin acts as a neurotransmitter, a neuromodulator or a neurohormone in the human hypothalamus.  相似文献   

18.
Posttransplant lymphoproliferative disorder (PTLD) is associated with Epstein-Barr virus (EBV), and may clinically resemble acute allograft rejection. Three methods to show EBV in tissue were evaluated in 15 liver allograft biopsies from 12 patients including four with PTLD: (1) semiquantitative polymerase chain reaction (PCR) for EBV DNA; (2) in situ hybridization for EBV RNA (EBER); and (3) immunoperoxidase for EBV latent membrane protein (LMP). Index cases had a PCR dot blot result of "positive" or "weak positive." Findings were correlated with histology, clinical data, therapy, and outcome. All four PTLD patients had a clinical diagnosis of acute rejection. All four showed EBV: PCR 4, EBER 4, LMP 3, Liver function tests were elevated in three, but EBV viral capsid antigen (VCA) IgM was not increased in three, but EBV viral capsid antigen (VCA) IgM was not increased in three. Immunosuppression was withdrawn and all four patients underwent a second transplantation. One died 4 days posttransplant with disseminated PTLD, two died of sepsis at 1.5 and 14 months, and one is well at 3 years without PTLD. Eleven biopsies without PTLD showed: acute rejection 7, acute rejection and hepatitis 1, hepatitis B 1, and non-inflammatory changes 2. In this group, EBV results included: PCR weak positive in 10 and 1+ in one, EBER negative in ten and rare positive cells in one, LMP negative in 11. Liver function tests were elevated in 10, whereas VCA IgM was not increased in three and increased in one. Patients with acute rejection were treated with increased immunosuppression: none developed PTLD, with follow-up of at least 6 months in nine cases. Two patients died within 4 months of biopsy. One patient with PTLD in tonsils had a liver biopsy showing both acute rejection and EBV (PCR 1+, rare EBER + small cells). Histological studies combined with special EBV detection methods, can be useful to evaluate atypical lymphoid infiltrates in liver allograft biopsies and confirmation of a diagnosis of PTLD. All three methods are useful; EBER and PCR are the most sensitive. EBER and LMP can use paraffin sections.  相似文献   

19.
The long-term effect of calcium channel blockers on chronic heart failure is disappointing, probably because of reflex sympathetic activation through arterial vasodilation. However, nilvadipine may be beneficial for treatment of chronic heart failure since this drug has minimal effects on sympathetic activation. In this study, the effects of 12-week administration of nilvadipine or placebo on symptoms of heart failure and cardiac function were investigated in 23 patients with mild-to-moderate chronic heart failure in a double-blind trial. The patients were randomly assigned to either a nilvadipine group (16 mg daily) or a placebo group. Intergroup comparisons did not show significant differences in any parameters. Serious adverse effects were not observed during the study. Thus, this study failed to show any beneficial effect of nilvadipine in the long-term treatment of patients with chronic heart failure. We conclude that the long-term administration of nilvadipine (16 mg daily) is neither effective nor harmful in the treatment of patients with chronic heart failure.  相似文献   

20.
BACKGROUND & AIMS: Although bacterial bowel flora may be one of the contributing factors in the pathogenesis of chronic mucosal inflammation, antibiotic treatment has no established role in ulcerative colitis. The aim of the study was to evaluate the role of ciprofloxacin in the induction and maintenance of remission in ulcerative colitis in patients responding poorly to conventional therapy with steroids and mesalamine. METHODS: Ciprofloxacin (n = 38; 500-750 mg twice a day) or placebo (n = 45) was administered for 6 months in a double-blind, randomized study with a high but decreasing dose of prednisone and maintenance treatment with mesalamine including follow-up for the next 6 months. Clinical assessment and colonoscopic evaluation were performed at 0, 3, 6, and 12 months. Treatment failure, the primary end point, was defined as both symptomatic and endoscopic failure to respond. RESULTS: During the first 6 months, the treatment-failure rate was 21% in the ciprofloxacin-treated group and 44% in the placebo group (P = 0.02). Endoscopic and histological findings were used as secondary end points and showed better results in the ciprofloxacin group at 3 months but not at 6 months. CONCLUSIONS: Addition of a 6-month ciprofloxacin treatment for ulcerative colitis improved the results of conventional therapy with mesalamine and prednisone.  相似文献   

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